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 I^HjHIBjHaHH HhB 
 
 
A PRACTICAL HANDBOOK 
 
 
 
 ^DYEING AND CALICO-PRINTING. 
 
 WILL [AM CROOK ES, L.i^S., S-c. 
 
 ■• 
 
 
 WITH ELEVEN I^CgE-Mflfcft , , Y SEVEN SPECIMENS OF DYED AND 
 
 PRINTED|yPreRICS. AND THIRTY-EIGHT WOODCUTS. 
 
 
 
 
 TP 
 
 
 
 950 
 
 
 
 C?4 
 
 
 
 15 
 
 
 
 LONDON 
 
 
 
 LONGMANS, GREEN, 
 
 AND 
 
 CO., 
 
 > 
 
 
 

 
 mi GETTY CENTE5 
 
 LIBRARY 
 
PREFACE. 
 
 A STANDARD work on Dyeing, Calico Printing, and their 
 Auxiliary Arts has hitherto been a desideratum in English 
 technological literature. In repeating this very common remark 
 we must not be understood as undervaluing the writings of Ban- 
 croft, O'Neill, Parnell, Napier, &c, nor the articles on Calico 
 Printing contained in Dr. Ure's " Dictionary of Arts, Manu- 
 factures, and Mines," and in Muspratt's " Chemistry." But 
 none of these works and treatises, however meritorious, can be 
 said to cover the whole of the subject. Most of them, further, 
 may in great measure be considered as possessing now a historical 
 rather than a practical value, having been written prior to the 
 wonderful development which tinctorial chemistry has experienced 
 with the last few years. Manuals of Dyeing and Printing com- 
 posed before the discovery of the coal-tar colours are now little 
 more than literary curiosities. 
 
 To meet this want the author has undertaken the task of laying 
 before the public in a compact, and, it is hoped, useful form, a 
 digest of the vast mass of information on the tinctorial arts found 
 scattered in distinct works, and in the scientific and technical 
 journals of all nations. Much has been of necessity omitted. 
 
 To give the briefest notice of every process tried on a practical 
 scale, much more of every laboratory experiment on the produc- 
 tion and application of colours, would require not a volume, but 
 a library. The author's object has been, therefore, — omitting 
 
VI 
 
 PREFACE. 
 
 procedures useless from their costliness, their uncertainty, and 
 the inferiority of their results, — to select matter which, # if not 
 positively valuable in itself, may be suggestive. It is hoped 
 that the information here collected, from sources rare and not 
 easily accessible, may not be without its value. 
 
 At the same time this book will not be found a mere compila- 
 tion of matter which already exists in print. The author has 
 been fortunate in obtaining the active co-operation of some of 
 the highest practical authorities in dyeing, printing, and the 
 manufacture of colours, and the work has been largely enriched 
 by their suggestions and the results of their experimental re- 
 searches. The kindness in this respect of Mr. S. Barlow, 
 the late lamented Dr. F. Crace-Calvert, Mr. Dale, Mr. J. 
 Higgin, Dr. R. Angus Smith, Dr. Schunck, of Manchester, 
 and Mr. W. H. Perkin, of London, cannot be too warmly 
 acknowledged. The author has also the pleasure of expressing 
 his obligations to Messrs. Brooke, Simpson, and Spiller, to 
 Messrs. W. Crum and Co., the late Mr. J. Lightfoot, with 
 his successors, Messrs. Grafton and Co., and Messrs. Wood 
 and Wright, for important information furnished, and for patterns 
 of dyed and printed fabrics supplied. 
 
 None can be more fully sensible than the author of the diffi- 
 culty of doing justice to a subject so vast, so complicated, and 
 so rapid in its growth ; but he sincerely trusts that, however 
 much his work fall short of perfection, it may still point out 
 remunerative fields of research to the student, and assist in the 
 development of British industry. 
 
CONTENTS 
 
 Introduction 
 
 page 
 i 
 
 DIVISION I. 
 
 CHAPTER I. 
 
 The Art of Dyeing in its Relation to Chemistry g 
 
 Water — Tests for Impurities, 10. Lime — Magnesia — Potash — Soda 
 — Iron — Arsenious and Arsenic Acids, II. Organic Matter, 13. 
 Boiler Incrustations, 14. 
 
 CHAPTER II. 
 
 Textile Fibres and Tissues made thekefbom— Thickenings and 
 
 Plastic Mordants 16 
 
 Mineral Fibres, 16. Mineral Thickenings — Vegetable Fibres — Vegetable 
 Thickenings — Cellulose, 17. 
 
 CHAPTER III. 
 Cotton 21 
 
 Mummy Cloth, 21. Cotton Wax, 34. Fatty Acid from Cotton, 36. 
 Colouring Matter, a, 37. Colouring Matter, I, 39. Pectic Acid, 40. 
 
 CHAPTER IV. 
 Bleaching 44 
 
 Bleaching Muslins — Bleaching Cotton Stockings, 50. Bleaching Cotton 
 Stockings Merino Shade, 51. Bleaching Cotton Stockings with 
 Turkey-red Tops — Bleaching Raw Cotton in Small Quantities — The 
 Continuous Process of Bleaching, 52. Bleaching with other 
 Chemical Agents, 56. 
 

 CONTENTS. 
 
 CHAPTER V. 
 
 Linen Fibre 
 
 page 
 • 57 
 
 Bleaching Linen — White, 57. Bleaching Linen Yarn— Colouring Linen 
 Yarn for Carpets on the Small Scale, 58. Yellow, Green, Red, 5g. 
 Orange with Madder — Orange with Annatto — Brown and Maroon — 
 Crimson, 60. Pensee Brown — Magenta — Aniline Purple — Aniline 
 Blue — Prussian Blue — Lilac, 61. Bismarck Slate — Cutch Brown 
 (Fast)— Black— Another Black, a Fast Colour, 62. 
 
 CHAPTER VI. 
 Hemp, Chinese Grass, Jute, and other Fibres 
 
 63 
 
 CHAPTER VII. 
 The Means of Distinguishing Vegetable Fibres from each other 65 
 
 CHAPTER VIII. 
 Vegetable Thickenings 66 
 
 Amylaceous Matters— Starch Fecula, C6H I0 5 or C I2 H 2 oO IO , 66. 
 Dextrine, 68. Gums — Gums Soluble in Water, belonging to the 
 Species of Arabic Gums, 6g. Gum Arabic — Gum Senegal, 70. 
 Gum Tragacanth, 71. 
 
 CHAPTER IX. 
 
 Animal Fibres— Thickenings of Animal Origin 73 
 
 Albumenoid Substances, 73. Albumen, 75. Qualitative Testing of 
 Albumen — Quantitative Estimation of Albumen, 78. Caseine — 
 Fibrine — Gluten, 78. 
 
 CHAPTER X. 
 Review of the Method of Applying Albumenoid Substances in 
 
 the Fixing of Colouks go 
 
 CHAPTER XL 
 
 Epidermic Products 
 
 Wool, 82. Bleaching Wool, 82. 
 
 CHAPTER XII. 
 Practical Recipes in Connection with Woollen Yarn and Fabrics 
 Bleaching— Another Method of Bleaching, 88. Colours on Woollens- 
 Blues— Woad, 8g. Soda or Potash Vat— A Decomposed Vat— Appli- 
 cations of the Woad Vat— Indigo Blue on Wool for Topped Hosiery 
 — Dark Blue for Wool for Broadcloth— Topped Logwood Blue, 90. 
 Indigo Flue, part Logwood— Purple Blue— Chrome Blue— Dark 
 Indigo Blue— Saxony Blue -Fast Prussian Blue, 91. Aniline Blue 
 — Reds on Wool — Scarlet — Scarlet Lac-dye — Cochineal Scarlet, 92. 
 Ponceau— Pink for Listings— Madder Red— Magenta— Crimson with 
 
 82 
 
 83 
 
CONTENTS. 
 
 Cochineal — Rose Pink, 93. Dahlia — Maroon — Yellows — Beige 
 Yellow — Orange — Salmon — Salmon with Madder, 94. Greens — Green 
 for Broadcloth — Another Green for Broadcloth — Logwood Green — 
 Chrome Green— Green for Yarn, 95. Aniline Green — Aniline Green 
 with Picric Acid— Olive Green — Olives — Bichrome Olive — A Cheap 
 Olive, 96. Olive en Zephyr — Browns — Chrome Brown — Chrome 
 Red Brown — Camwood Brown — Fast Brown — Light Brown, 97. 
 Bismarck— Aniline Bismarck — Mode with Indigo Bottom — Mode 
 without Indigo — Drab — Slates, 98. Purple Slate — Stone Colour — 
 Silver Grey — Lavender — Aniline Purple — Blacks — Chrome Blacks, 99. 
 Sumach Black — Fast Black — Cheap Black — Black for Silk Striped 
 Thibets— Colours on Wool and Warps — Slates and Modes on White 
 Warps, 100. Magenta on Cotton Warps — Purple on Cotton Warps 
 — Scarlet on Cotton Warps — Saxon Blue on Cotton Warps — Aniline 
 Blue on Cotton Warps — Black and Orange on Cotton Warps — Green 
 on White Warps, 101. Randoms or Clouded Yarns — Scarlet Random 
 — Orange Random — Saxon Blue Random, 102. Prussian Blue 
 Random — Magenta Random — Purple Random, 103. 
 
 CHAPTER XIII. 
 
 Silk 
 
 104 
 
 Bleaching Silk, 106. Means of Distinguishing Silk and other Fibres, 
 107. Manilla — Sizal — New Zealand Flax — Phormium Tenax, 107. 
 
 CHAPTER XIV. 
 
 Potash, Soda, and Lime Salts no 
 
 Potash, no. Nitrate of Potash — Bisulphate of Potash — Chromate of 
 Potash — Oxalate of Potash, in. Manganate of Potash — Perman- 
 ganate of Potash — Tartar — Potash Water Glass, 112. Chlorate of 
 Potash— Hypochlorite of Potash — Soda Salts — Carbonate of Soda, 
 113. Silicate of Soda, 118. Chloride of Sodium — Hypochlorite of 
 Soda — Phosphate of Soda — Permanganate of Soda — Tungstate of 
 Soda — Hyposulphite of Soda, 119. Lime Salts — Hypochlorite of 
 Lime — Ammoniacal Salts — Ammonia, 120. Carbonate of Ammonia 
 — Sal-ammoniac — Nitrate of Ammonia, 121. 
 
 CHAPTER XV. 
 Alkalimetry 122 
 
 The Test Solutions — The Litmus Solution — Normal Sulphuric Acid 
 Solution, 122. Normal Oxalic Acid Solution — Normal Hydrochloric 
 Acid Solution— Normal Nitric Acid Solution, 124. The Estimation 
 of Carbonated Alkalies, 125. Estimation of Caustic Alkalies, 128. 
 Acidimetry, 131. 
 
 CHAPTER XVI. 
 Chlorine, Chlorides, and Chlorimetry 132 
 
 Estimation of the Chlorine in Chlorine Water, 140. Estimation of 
 Hypochlorites, 141. 
 
CONTENTS. 
 
 DIVISION II 
 
 CHAPTER I. 
 
 The General Principles of the Fixation of Colouring Matter 
 
 upon Fibrous Textures — Classification of Dye-Materials 142 
 
 CHAPTER II. 
 
 Mineral Pigments !5> 
 
 White Colouring Matters — Chalk or Carbonate of Lime — Sulphate of 
 Lime or Gypsum, 150. Sulphate of Baryta, 151. Red Mineral Pig- 
 ments, 152. Vermillion Red (specimen), 153. Yellow Mineral Pig- 
 ments, 150. Chrome or Canary Yellow (specimen) — Iron Buff 
 (specimen), 155. Green Mineral Pigments, 156. Chrome Green 
 (specimen) — Wilner, an Arsenical, Green (specimen), 157. Blue and 
 Violet Pigments — Ultramarine, 158. Ultramarine (specimen), 160. 
 Cyanogen Colours, 162. Dark Blue (specimen)— Light Blue (specimen), 
 164. Ordinary White Tin Pulp— Blue Tin Pulp, 166. Cobalt Blues, 
 
 CHAPTER III. 
 Colouring Matters of Organic Origin Artificially Obtained . . 168 
 Colours Derived from Uric Acid — Purpurates— Murexide, 168. Purple 
 of the Ancients — Colours Derived from Aniline and Kindred Bodies, 
 171. Aniline Reds, 17S. Examination of Magentas, 185. Magenta 
 (specimen) — Ponceau (specimen), 187. Aniline — Crimson — Ponceau — 
 Perkin's Violet or Mauve, 187. Hofmann's Violet (specimen), 194. 
 Aniline Blues, 195. Aniline Greens — Iodine Green or Bimethyl- 
 Iodhydrate of Trimethylic Rosaniline, 202. Nicholson's Blue 
 (specimen) — Saffranine Pink (specimen), 203. Soluble Green, 204. 
 Crystalline Green — Aldehyde Green, 205. Rosanaphthylamine or 
 Naphthylamine Red — Geranosine, 206. Saffranine — Phoenicine — 
 Aniline Browns, 207. Aniline Yellows and Oranges, 209. Aniline 
 Orange — Aniline Greys, 210. Aniline Black, 211. Aniline Black 
 (specimen) — Coloured Derivatives of Phenol, 215. Aurine Orange — 
 Coralline Yellow, 217. Isopurpuric Acid, 219. Rothine or 
 Phenicienne — Vesuvine — Naphthalin Colours, 220. Naphthylamine 
 Violets — Naphthylen Diamine Violets — Naphthalin Yellow, 221. 
 Anthracen Colours — Artificial Alizarin, 222. Reds — Pinks — Red for 
 Mosaics — Another Red without Oil, 225. Purple — Thickening for 
 Purple — Thickening for Reds — Acetate of Alumina— Nitrate of 
 Alumina, 226. Acetate of Lime — Brown, 227. 
 
 CHAPTER IV. 
 
 Colouring Matters of Vegetable and Animal Origin 228 
 
 Madder and other Rubiacese, 228. Substances Soluble in Cold Water 
 — Glucose — Cane Sugar — Gum and Mucilage, 233. Pectose — 
 Chlorogenin — Alkaline Tartrates — Malates — Citrates — Substances 
 Soluble in Boiling Water and in Alcohol, 234. Rubian, 239. Alizarin, 
 245. Purpurin, 247. Original Colours Soluble in Water— Glucosides 
 
CONTENTS. 
 
 — Rubian — Ruberythric Acid — Colouring Matters the Existence of 
 which cannot be Doubted — Alizarin — Purpurin — Orange Matter — 
 Pseudopurpurin — Purpuroxanthin — Xanthopurpurin — Colouring 
 Matters of Doubtful Existence or which Require Further Investi- 
 gation — Yellow Matters — Resinous Matters — Commercial Produces 
 or Derivatives from Madder, 252. Garanceux, 261. Mechanical 
 Process of Purifying Madder, 263. Testing of Madders — Fleur de 
 Garance — Garancin Extracts, 269. Use and Application made of 
 Madder and its Preparation for Dyeing Purposes, 273. Bleaching — 
 Printing and Fixing the Mordants — Mordants for Red-Pink — Rose 
 Colour, 275. Strong Mordant No. 1 — Mordant No. 2 — Strong Mor- 
 dant, 2S3. 5 '4 Mordant — Red Mordant (Liquor) for Garancin — Strong 
 Mordant — Mordant for Red with Garancin, 284. Red Mordant for 
 Madder — Bright Red — Red Mordant — For Deep Red — Red Liquor or 
 Mordant — Other Red Mordant — Red 4/2 — Mordants for Rose Colour 
 — Pink, 288. Red Liquors from Acetate of Lime — Red Liquor for 
 Madder Pink (Rose Colour), 289. Mordants for Brown and Chocolates, 
 292. A. Ordinary Madder Style Work, 307. B. Garancin Style, 
 308. Madder — Printing, 315. Discharge and Resist Processes, 317. 
 Reserves, 319. Turkey-red, 321. Madder (specimen) — Artificial 
 Alizarin (specimen), 326. Substitutes for Madder, 329. 
 
 CHAPTER IV.* 
 Red Woods — A. Open on Soluble Class — B. Close or Insoluble 
 
 Class 331 
 
 Santal Wood — Sanders Wood or Red Sanders, 339. Caliatur or 
 Cariatur Wood — Madagascar Wood — Barwood, 341. Camwood or 
 Kambe Wood — Logwood or Campeacby, 342. Red Colouring Matters 
 — Cochineal — Kermes — Lac-lake — Gum-lac — Lac-dye, 350. Animal 
 or Vegetable Kermes — Scarlet Grain — Oak Cochineal — Gum-lac or 
 Resin-lac, 353. Shellac, 354. Carminic Acid, 357. Ammoniacal 
 Cochineal, 358. Carmine, 359. Harmala Red — Erythrose, 364. Fustic 
 Carmine— -Preparation of Lake Colours— A. Red Lakes — Madder Lake, 
 365. Lakes of the Red Woods — Cochineal Lakes — B. Blue Lakes — 
 C. Green Lakes, 366. D. Yellow and Orange Lakes — Annatto Lakes 
 — Fustic Lakes — Aniline Lakes — Colouring Matters Derived from 
 Lichens, 367. Chemical History of the Colouring Matters of 
 Lichens, 369. Erythric Acid — Erythrine, 370. Picrocrythine, 371. 
 Orsellic or a-Orsellinic Acid — Lecanoric, Diorsellic, a-Orsellic Acid, 
 or Lecanorine, 372. Rocellinine — Parelline, or Parellic Acid — 
 Colouring Matters of Orchil, 374. New Methods of Preparing 
 Orchil, 375. Applications of Orchil in Dyeing and Printing, 379. 
 Amaranth Red — Amaranth Bright — Amaranth Violet — Feuille Morte 
 — Novel Colour, 380. Litmus, 381. Alkanet — Safflower, 384. Cartha- 
 
 min, 385. 
 
 CHAPTER V. 
 
 Colouring Matters of Various Origin 388 
 
 Chica — Crajura — Carajara, 388. Colouring Matters contained in 
 the Sorgho — Sorgho Red — Rose-Red, Pink-Red, and Blue Colouring 
 Matters of blowers, 389. Colouring Matters of the Malvaceae, 390. 
 
Sooranjee — Root of the Morinda citrifolia, 391. JEnoVm, or Red 
 Colouring Matters of Wine, 392. Yellow Vegetable Colours, 393. 
 Quercitron, 395. Colouring Matters contained in Quercetin, 396. 
 Use made of Quercitron, 401. Persian Berries, 403. Fustic — 
 Yellow Brazil Wood — Cuba Wood — Yellow Wood — Old Fustic, 405. 
 Morintannic Acid, 406. Weld, 408. Rutin— Robinin, 410. Rham- 
 noxanthin — Colouring Matter of Thuya occidentalis — Fustet — 
 Young Fustic — Zante Fustic, 411. Colouring Matter from Buck- 
 wheat, 412. Dyeing with Weld, 413. Upon Cotton, 414. 
 Aloes, 415. Turmeric, 418. Yellow Colouring Matters of Chinese 
 Origin, 421. Saffron, 422. Barberry Bark, 423. Yellow Colouring 
 Matters contained in Flowers — Carotin — Yellow Colouring Matter 
 of Carrot-Roots, 424. Purrhee or Indian Yellow — Yellow Colouring 
 Matters of the Lichens — Chrysophanic, Vulpic, and Usnic Acids, 425. 
 Chrysinic Acid— Gentianic Acid — Annatto or Anotto, also known as 
 Rocou, Bixin, or Orleans, 426. Green Colouring Matters — Chinese 
 Green — Lokao, 428. Green Dyeing, 432. French Process for 
 Dyeing with Lokao, 433. Other Green Dyes of Vegetable Origin, 
 434. Chlorophyl — Chromule — Green Colouring Matter of Leaves 
 and other Green Parts of Plants, 435. Blue Colouring Substances, 
 438. Indigotin, 439. Sulphindigotic Acid, 445. Indigo, 447. 
 Woad or Pastel, 453. Industrially-prepared Sulphuric Acid De- 
 rivatives of Indigo — Indigo-Carmine — Purple-Blue, also known 
 as Boiley Blue, 463. Fixing Indigotin by the Reduction Method, 
 468. Reduction of Indigo — Theory of Indigo-Vats, 469 
 
 CHAPTER VI. 
 Brown and Black Colouring Matters — Astringents 
 
 Kino, 4gi. Catechu, 493. True Astringents — Galls, 499. Gallein 
 — Alder Bark, 508. Algaroba — Amalic Acid — Anthokirrin— Areca 
 Nuts — Bablah — Neb-neb — Neb-nab — Babulah — Barbatimas — Bear- 
 berry — Bilberries, 509. Brauna Wood — Butter-nut Bark — Caclin — 
 Canadian Yellow-root — Carapa-roct — Chestnut — Chicory — Chrysore- 
 tin — Coccedia viridis — Cocoa-nut Tree — Cork, 510. Dyer's Wood- 
 ruf — Gammam — Golden-rod — Green Ebony — Heath — Hellebore — 
 Hemlock — Hiccory — Holly — Hollyhock — Horse-chestnut — Horse- 
 radish — Khailcedra — Lamium album — Lamium purpureum — Law- 
 sonia inermis — Lithospermum arvense, 511. Mahaleb — Mahogany 
 Tree Bark — Mangrove — Nitrocuminic Acid — Nucin — Nymphaja 
 alba — Palisander Wood — Paracarthamin — Phycocyan — Pi ttacal — 
 Polygonum tindtorium — Pomegranate-root Bark — Purple Heart — 
 Privet Berries, 512. Saw-wort — Sunflower Seeds — Syria — Viridic 
 Acid — Virginia Creeper — Preparation of Extracts of Dye- Woods, 513. 
 
 CHAPTER VII. 
 Mordants 5x6 
 
 Mordants, technically lyiown as "Tin-Spirits," 519. Proto-Salts of 
 Tin and their Solutions, 522. Double Muriate of Tin, 523. Single 
 Muriate of Tin -Proto-Salts of Tin-Spirits, 524. Oxalate of Tin. 
 
 490 
 
CONTENTS. 
 
 525. Claret Spirit— Sesquisalts of Tin, 526. Nitrate of Tin, 527. 
 Purple Spirit for Wool and Worsted — Aniline Spirit — Hellot's 
 Mordant, 528. Stannic Salts, or Per-salts of Tin, 529. Bichloride, 
 Perchloride, or Tetrachloride of Tin — Stannic Chloride — Chloro- 
 stannic Acid — Fuming Spirit of Libavius — Aqueous Bichloride, or 
 Stannic Chloride of Tin — Red Cotton Spirits, known as Crimson 
 Spirits, 530. Barwood Spirit — Plum Spirit — Solution of Tin, 531. 
 No. 2 Solution — Oxymuriate of Tin — Pink Salt, 532. Alumina 
 Mordants — Aluminate of Soda — Aluminate of Potash, 534. Iron 
 Mordants — Copperas — Green Vitriol — Protosulphate of Iron — Ferrous 
 Sulphate, 535. Persulphate o'f Iron — Muriate of Iron — Permuriate of 
 Iron — Black Liquor — Nitrate of Iron, 536. Common Iron for Drabs, 
 539. Alkaline Iron Mordants — Lead Mordants — Nitrate of Lead — 
 Sulphate of Lead — Alkaline Solutions of Lead, 541. Tungsten 
 Mordants — Antimony Mordants, 542. Bismuth Mordants, 543. 
 Chromium Mordants, 544. Manganese Mordants — Zinc Mordants — 
 Arsenic Mordants — Copper Mordants, 545. Ammoniuret of Copper, 
 546. Chloride or Muriate of Copper — Nitrate of Copper — Sulphate 
 of Copper, 547. Tartar and Argols, 548. Tartaric Acid, 549. Super 
 Argol — Royal Blue Spirits, 550 
 
 CHAPTER VIII. 
 Printing .. 
 
 Perrotine, 551. Cy inder Machines, 560. Mixing Colour, 561. 
 Thickeners, 563. Madder Colours, with Several Variations — 
 Garancin Colours— Reserved Style, 564. Padding Styles — Indigo 
 Blues — China Blues — Turkey Red, with Discharges — Steam-Colours 
 — Spirit-Colours, 565. Bronzes — Pigment-Colours — First Style — 
 Madder, 566. Mordants — Discharges — Reserves — Covers, 572. 
 Plate Style — Plate Pinks, 575. Madder Red and Pink (specimen), 
 576. Madder Style, First Stage (specimen) — Madder Style, after 
 Dyeing (specimen), 577. Madder Style, after Clearing (specime?i),^j8. 
 Madder and Aniline Black (specimen) — Garancin (specimen) — Third 
 Style, Reserved, 580. Fourth Style— Padding, 581. Fifth Style- 
 Indigo Effects, 585. Indigo Style, First Stage (specimen), 590. Indigo 
 Style, Second Stage (specimen) — Indigo Style, with other Colours, Third 
 Stage, 591. Style produced by Lightfoot's Patent Process (speci- 
 men), 592. Sixth Style — China (Indigo) Blues, 593. Seventh Style 
 — Discharges on Turkey Reds, 594. Eighth Style — Steam-Colours, 
 598. Standard Brown, Light (specimen) — Standard Brown, Dark 
 (specimen), 604. Aloes Green, 607. Cochineal Pink (specimen), 609. 
 Pale Yellow, from Persian Berries (specimen) — Dark Yellow, from 
 Persian Berries (specimen), 612. Hofmann Violet on Calico (specimen) 
 — Delaines, 613. Printing Delaines, 617. Woollen Goods, 624. Silks, 
 630. Ninth Style — Spirit-Colours — Application Colours, 635. Tenth 
 Style — Manganese Bronzes, 638. Eleventh Style — Pigment Printing, 
 639. Guignet's Green and Chrome-Green — Chrome-Black and Di- 
 chromate of Lead (specimen) — Ultramarine Blue, Chrome-Black, and 
 Dichromate of Lead, 641. Ultramarine and Madder Extradt (speci- 
 men) — Carbonaceous Grey, with Chrome-Black — Chrome-Green, 
 
 551 
 
XIV 
 
 CONTENTS. 
 
 PAGE 
 Chrome-Yellow, and Extract of Madder (specimen), 643. Extract of 
 Madder. Red and Pink, with Chrome-Orange, Green, Ultramarine 
 Blue, and Chrome-Black (specimen). 644. Green Padded Ground, 
 with Design in Madder, Red, and Pink, Chrome-Orange, Green, and 
 Black (specimen) — Chrome-Orange, Light and Dark (specimen), 645. 
 Aniline Black, with Madder Red and Chrome-Orange (specimen), 647. 
 Aniline Black, 649. Murexide Purples, 650. Operations Accessory 
 to Dyeing, 651. Influence of Light upon Colours, 655. A&ion of 
 Light, 659. 
 
 CHAPTER IX. 
 
 Detection of Dves on Yarn or Pieces •• .. .. 662 
 
 Blacks, 662. Blues, 663. Yellows, 664. Reds, 665. Greens, 666. 
 Violet, 667. Behaviour of Colours on Different Fibres with Re- 
 agents — Aniline Colours, 669. Cochineal Colours, 670. Madder 
 Colours. 671. Fustic — Flavin — Quercitron Extrad, 672. 
 
 APPENDIX. 
 
 Preparation of Picric Acid, 673. Isopurpuric Acid — Rosolic Acid — 
 Fol's Yellow — Campo-Bello Yellow — Phenicienne — Chloride of Ben- 
 zyl, 674. Diphenylamine — Cerise — Coupier's Aniline Reds — Hof- 
 mann's Xylidin Red, 675. Ulrich's Scarlet — Hofmann Violet, 
 R.R.R. — Dorothea Violet — Wanklyn's Violet— Paris Violet (Poir- 
 rier's Violet), 676. Hofmann Violet, R.R.R. (specimen) — Spiller's 
 Purple (specimen) — Lauth's Violet, 677. Methyl-diphenylamine 
 Violet — Paris Green — Methylaniline Green — French Yellow; Chry- 
 seic Acid (Nitro-xynaphthalic Acid of Dusart and Gelis), 678. 
 Carminaphtha — Chloroxy-naphthalic Acid — Ballo's Violet — Naph- 
 thoic Blue, 679. Aniline Grey, Castelhaz (specimen) — Naphthols, or 
 Naphthylic Alcohols, 680. Anthracen-Orange, 681. Artificial Iso- 
 purpurin,682. Anthrapurpurin — Aurin (Yellow Corallin, Rosolic Acid), 
 683. Derivatives of Resorcin — Derivatives of Hydroquinon — Deri- 
 vatives of Pyrocatechin — Gallein, 684. Nitrous Derivatives of 
 Resorcin — Cyanin, 685. Aloes — Dalleiochin, 686. Rufigallic Acid, 
 687. Adulteration of Albumen — Dyeing Aniline Blacks on Cotton 
 Yarn — Printing-Ink for Use in Calico-Printing, 688. New Iron Mor- 
 dant — New Aniline Red — Printing Aniline Colours on Calico — Use of 
 Epsom Salts in Dyeing — Test for Saffranin — Cochineal-Red on 
 Cotton, 689. — Method of Determining Anthracen— New Class of 
 Colouring Matters, 690 Vat-Blue Ground, with a Red, Brown, Black, 
 and White Pattern, 691. Black and White on a Madder Red Ground 
 — Dark Spirit Violet on Cotton Warps, 692. Dale's Patent Process 
 for Printing and Dyeing with Aniline Colours, 693. Artificial Orchil, 
 694. Chemical Removal of " Burls " from Wool and Woollen 
 Goods, 695. Coralline — Hydrometer Tables — Baum£'s Scale — Beck's 
 Scale— Carth-r's Scale, C97. Thermometer Scales, 699. Decimal 
 or Metric Weights and Measures— Measures of Length, 699. Super- 
 ficial Measures — Measures of Capacity, 700. Weights, 701. Biblio- 
 graphy, 702. 
 
fxv) 
 
 LIST OF PAGE PLATES. 
 
 Dye House at the Gobelins, Paris ..... 
 
 Plan of Dye Works 
 
 Manufa&ure of Aniline Blue 
 
 Retorts for Distilling Methyl-Aniline .... 
 
 Block-Printing. Painting in Reserves by Hand . 
 
 Gas-Process for Engraving Blocks for Printing. Designs 
 Produced by the Gas-Process .... 
 
 Blocks Successively Applied to Produce the Different 
 Shades in a Design. Machine for Engraving Copper 
 Cylinders. ........ 
 
 Singeing House ........ 
 
 Washing-Machine for Blacks ...... 
 
 Drying Apparatus ....... 
 
 Finishing-Machine ........ 
 
 . (Frontispiece.) 
 
 To face page 88 
 
 ,1 ., 17 6 
 
 ii .. 192 
 
 292 
 
 55i 
 
 . 554 
 
 608 
 
 624 
 
 640 
 .-§56- £7 
 
 LIST OF WOOD ENGRAVINGS. 
 
 PAGE 
 
 Barlow's Method of Bleaching under Pressure . . . . 46, 47 
 
 Bentley's Continuous Process of Bleaching .... 53, 54 
 
 Elevation and Ground Plan of a Bleach House . . . . 55. 56 
 
 Fibres of Cotton, Silk, and Woollen Fibres .... 108, 109 
 
 Lixiviation Process .......... 115 
 
 Alkalimeter Tube 123 
 
 Preparation of Aniline Red 180, 182 
 
 Preparation of Aniline Violet 193 
 
 Preparation of Aniline Blue 198 
 
 Preparation of Aniline Green 203 
 
 Preparation of Alizarin 268 
 
 Madder Dyeing 306 
 
 Preparation of Dye-woods 514 
 
 Perrotine Machine for Printing 552, 553 
 
 Cylinder Machine for Printing 555 
 
 End Elevation and Sedtion of a 4-Colour Machine . . . 556, 557 
 
 12-Colour Machine .......... 559 
 
 20-Colour Machine ........ . 559 
 
 8-Colour Machine .......... 560 
 
 Colour Mixing Pans 561 
 
 Graining Machine 562 
 
 Padding Flue 582 
 
 Apparatus for Sulphuring Delaines " 164 
 

 xWOiri 
 
 w 
 
 (xvi ) 
 
 SPECIMENS OF DYED AND PRINTED FABRICS. 
 
 PAGE 
 
 Vermillion-Red 153 
 
 Chrome-Yellow (Canary) .......... 155 
 
 Iron Buff 155 
 
 Chrome-Green ............ 157 
 
 Wilner Green (Arsenical) 157 
 
 Ultramarine ............ 160 
 
 Dark Prussian Blue 164 
 
 Light do. do 164 
 
 Magenta ............ 186 
 
 Ponceau (Brooke, Simpson, and Spiller's) 186 
 
 Hofmann's Violet, B. ......... . 194 
 
 Nicholson Blue, 4 B. 203 
 
 Saffranine Pink 203 
 
 Aniline Black 215 
 
 Aurine Orange ........... 217 
 
 Coralline Yellow 217 
 
 Turkey Red, Madder ; . 326 
 
 Do. Artificial Alizarin ........ 326 
 
 Madder, Red and Pink 576 
 
 Madder Style, First Stage 577 
 
 Do. after Dyeing 577 
 
 Do. after Clearing 578 
 
 Madder with Aniline Black 579 
 
 Garancin ............. 579 
 
 Indigo (Lightfoot's), First Stage 590 
 
 Do. do. Second do 591 
 
 Do. do. Third do 591 
 
 Style produced by Lightfoot's Patent 592 
 
 Do. do. 592 
 
 Brown (Catechu), Light 604 
 
 Do. do. Dark 604 
 
 Cochineal Pink 609 
 
 Yellow, Pale (Persian Berries) 612 
 
 Do. Dark do. 612 
 
 Hofmann Violet (Calico) 613 
 
 Guignet's Green and Chrome-Green, Chrome-Black, and Dichromate of 
 
 Lead 641 
 
 Ultramarine Blue, Chrome-Black, and Dichromate of Lead . . 641 
 
 Ultramarine with Vermillion and Chrome ...... 642 
 
 Do. with Madder Extract 643 
 
 Carbonaceous Grey, with Chrome-Black, Chrome-Green, Chrome-Yellow, 
 
 and Extract of Madder 643 
 
 Extract of Madder, Red and Pink, with Chrome-Orange, Green, Ultra- 
 marine Blue, and Chrome-Black 644 
 
 Green Padded Ground, with Design in Madder, Red and Pink, Chrome- 
 Orange, Green, and Black 645 
 
 Chrome-Orange, Light and Dark 645 
 
 Aniline Black, with Madder Red and Chrome-Orange .... 647 
 
 Hofmann Violet, R.R.R 677 
 
 Spiller's Purple 677 
 
 Aniline Grey (Castelhaz) 680 
 
 
A HANDBOOK 
 
 OF 
 
 DYEING AND CALICO PRINTING. 
 
 INTRODUCTION. 
 
 ^pHE introduction of a number of new dyes resulting from chemical 
 research has rendered very desirable the publication of a complete work 
 containing the latest and most reliable information on the subject, and never- 
 theless confined within reasonable limits. 
 
 Few branches of human industry are more intimately connected with 
 science than the art of dyeing and printing, that is to say, the application of 
 colouring matter to vegetable and animal tissue. To recount the numerous 
 branches of science with which the art of dyeing is more or less associated 
 would be tedious and unprofitable, but the following instance will serve as an 
 example : — The substance known as cochineal, which in its native country, 
 Mexico, was used as a dye and cultivated by artificial means at a very remote 
 period of history, was long supposed to be the dried seed of a plant. Aftei 
 the year 15 18 it was introduced into Europe, but its real constitution was not 
 known until the 17th century, when it was accidentally discovered to consist 
 of the body of an insect, the Coccus cacti. The dye yielded by cochineal 
 being valuable, and capable of producing many shades of colour, attempts 
 were soon made to introduce into other countries the plant upon which the 
 insect lives and feeds. To do this with success it became necessary to 
 study minutely the habits of a very small insect, and to inquire attentively 
 into the climatologicai and all other conditions of its life. Nor was this all, 
 for recent experience has taught us that even in localities favourable to the 
 growth of the species of cactus upon which the insect lives, the Coccus cacti 
 itself languishes or becomes extinct if the spot where it is located be too near 
 the sea and subject to the influence of damp winds. Here is a demonstration 
 of simultaneous connection with the sciences of Natural History, Botany, 
 and even Meteorology. The position of the art of dyeing and printing with 
 
$$$$s$fi&ffl 
 
 
 riff 
 
 2 DYEING AND CALICO PRINTING. 
 
 regard to Chemistry and Mechanical Science is too obvious for comment, but 
 attention must be drawn to the important fact that, notwithstanding the 
 progress made in those sciences with which the art has more or less in 
 common, our knowledge of the subject itself is but slight. We are entirely 
 ignorant of the laws which govern the combination of dyes and pigments 
 with fibrous tissue, and totally unable to point out the chemical difference 
 between white and coloured fibre, or to explain the causes of the appearance 
 or disappearance of colour. There is not a single experiment on record 
 which will enable the reader to judge whether colouring tissue by dyeing is 
 a chemical phenomenon or not ; neither does there exist a quantitative 
 determination of the amount of alumina, iron, or tin, which may combine 
 with or be attached to cotton, wool, or silk. It is, moreover, still uncertain 
 how much colouring matter may combine with these metals, and whether any 
 definite compounds exist ; in fact, there is no chemical theory of dyeing 
 worthy of the name. 
 
 The history of dyeing is another question. 
 
 Its invention or discovery may be said to have been coeval with the first 
 traces of civilisation ; it is impossible to determine the time when the art of 
 imparting colours to fabrics was first practised, but there is reliable historical 
 evidence as to its antiquity. In those portions of Asia where at a remote 
 period there existed a high degree of civilisation, a somewhat advanced 
 proficiency in the art appears to have been reached, especially in Phoenicia, 
 whose capital city, Tyre, was the Manchester of antiquity, and about fourteen or 
 fifteen centuries before the Christian era became celebrated for the production 
 and application of the famous Tyrian purple. 
 
 According to Pliny and Aristotle, this valuable and costly dye was obtained 
 from a kind of mollusc, a little reservoir in the throat of which on being 
 pierced yielded one single drop of liquid. This liquid, at first colourless, 
 became gradually lemon-coloured, then sky blue, and in a few days purple. 
 Bancroft (" On Permanent Colours ") says regarding it :— 
 
 " To avoid the trouble of opening the small reservoir in each fish the 
 smallest species was generally bruised whole in a mortar, though the other 
 fluids of the fish must have necessarily debased the colour in some degree. 
 The liquor when extracted was mixed with a considerable portion of salt to 
 preserve it from putrefaction, and was then diluted with five or six times as 
 much water, and kept moderately hot in leaden or tin vessels for the space of 
 ten days, during which the liquor was often skimmed to separate all im- 
 purities ; after which the wool, being first well washed, was immersed and kept 
 therein for five hours, then taken out, carded, and again immersed, and con- 
 tinued in the liquor until all the colour was exhausted. To produce particular 
 6hades of colour, nitre, urine, and a marine plant called Fucus were 
 occasionally added. Several of these varieties of colour have been par- 
 ticularly mentioned by ancient writers. One of them, which was very dark, 
 seems to have been a violet, inclining towards the reddish hue ; ' Nigrantis 
 rosce colore sublucens' (Pliny, lib. ix., sect. 50). Another, and less esteemed, 
 was probably a kind of crimson ; but the most esteemed, and that in which 
 the Tyrians particularly excelled, resembled coagulated blood; l laus ei summa 
 in colore sanguinis concrcti ' (Pliny, sect. 62). There was, moreover, a 
 fourth kind known in later times, an account of which may be found in 
 
INTRODUCTION. 
 
 Perrault's translation of ' Vitruvius.' Pliny says ' the Tyrians first dyed 
 their wool in the liquor of the purpura, and afterwards in that of the buccinum ; 
 the purple mentioned in Exodus, chap, xxv., was also twice dyed. Wool 
 which had received this double Tyrian dye (dibapha) was so very costly, that 
 in the reign of Augustus each pound of it sold for iooo Roman denarii (about 
 ^36 sterling). But lest this should not sufficiently exclude the use of it from 
 all who were not invested with the highest dignities, laws were made inflicting 
 severe penalties, and even that of death under the later emperors, upon all who 
 might presume to wear it. The art of dyeing this colour came at length to 
 be practised only by a few individuals, appointed and maintained by the 
 emperors for that purpose ; and it being interrupted about the beginning of the 
 12th century all knowledge of it was soon after lost, except what remained in 
 the more ancient writings ; and during several ages this celebrated dye was 
 considered and lamented as an irrecoverable loss." 
 
 This dye, in addition to its beauty, must also have been very fast, for it is re- 
 corded that when the town of Susawas taken by the Greeks a large and valuable 
 collection of purple cloth was found amongst the treasures of the Persian king 
 Darius, and notwithstanding it had been kept for a period of 190 years, its 
 lustre and beauty were undiminished. This account may be received 
 as substantially correct, inasmuch as it is related by no less a person than 
 Plutarch. A complete history of this subject would occupy the entire space 
 of a large volume, but the following brief outline may prove useful to the 
 reader. 
 
 " The earliest important event in the history of dyeing was the discovery of 
 the effects of bases or mordants, and particularly that of alum in fixing 
 adjective colouring matters. When or where this discovery was first made 
 cannot be ascertained ; there is, however, good reason to believe that alum 
 and probably iron salts (which are the principal bases of modern calico 
 printing) were employed by the Egyptians in producing those effects which 
 are described by Pliny, lib. xxxv.,sect. 42 ; because they resemble others which 
 calico printers now obtain by these means, and which at this time they cannot 
 obtain by any other, even with all the knowledge since acquired ; and it has 
 been proved that the Egyptians borrowed this art from Hindostan, where it 
 appears to have subsisted for more than 2000 years, probably with very little 
 if any variation or improvement during that long space of time ; and if we 
 may judge of the means formerly employed in Hindostan for dyeing or 
 staining calicos by those which were found to be in use for that purpose when 
 the nations of Europe first went thither by the Cape of Good Hope, we may 
 safely conclude that solutions of alum and of iron must have been the 
 mordants employed in fixing the adjective colours." — Bancroft, " On Permanent 
 Colours." 
 
 Very little is now known as to the proficiency of the ancient inhabitants of 
 India in the arts of dyeing and weaving, but there is evidence to prove that 
 the ancient nations who dwelt in that portion of Asia just alluded to, and also 
 the ancient inhabitants of Mexico and Peru, enjoyed an advanced degree of 
 civilisation, and were by no means wanting in skill in applying colours to 
 woven tissues. Notwithstanding the aesthetical progress in civilisation made 
 by the Greeks, they appear to have advanced but little in the art of colouring 
 woven fabrics, and were in this respect greatly behind the ancient Romans. 
 
DYEING AND CALICO PRINTING. 
 
 No records remain regarding the operations carried out and processes invented 
 by the latter, but it is certain that they were acquainted with the use of such 
 substances as madder, woad, nutgalls, and alkanet root, and with the 
 application of blue and green vitriol, alum, and even some salts of lead. 
 According to Dioscorides and Pliny, who lived in the ist century, indigo was 
 known in Europe, and although scarce, was regularly imported ftom India, 
 whence its name is derived. The natives precipitated and collected in a dry 
 solid form the colouring matter of indigo, and, what must have been a much 
 greater difficulty, they afterwards discovered the means of dissolving it and 
 rendering it capable of being permanently fixed upon the substances intended 
 to be stained or dyed with it ; an effect which the Greeks and Romans do not 
 appear to have ever produced, though they knew how to powder and apply 
 indigo as a paint. 
 
 " It appears that wool* was never worn in China but as a substitute for fur, 
 and that cotton and silk, being the only substances ever dyed by the inhabi- 
 tants, received all their colours from vegetable tinctorial matters ; that these 
 colours were principally red, blue, violet, and what is called a woad colour ; 
 and that under the three first dynasties the business of dyeing was chiefly 
 practised by the female part of each family for its own particular use : and it 
 probably continued to be practised without anything like principle or science 
 until near the end of the 7th century, when the Chinese, discarding their own, 
 borrowed the art and means of dyeing which were then in use among the 
 Hindoos and Persians ; and it is said that alum and copperas, which the Chinese 
 did not use before, were among the means so borrowed, a fact which renders it 
 probable that there was little, if anything, in the Chinese art of dyeing of 
 which the loss need now be regretted. 
 
 " It appears, however, that long before this time a knowledge of the uses of 
 alum and of iron salts in dyeing had spread from Hindostan and Persia west- 
 ward to Egypt, and thence to Greece and Rome. Bergmann, indeed (" De 
 Confect. Alum"), and, after him, Beckmann (in the " Gottingen Memoirs"), 
 have represented the alum of the ancients as differing from the crystallised salt 
 so-called by the moderns, and have supposed that the varieties of alum men- 
 tioned by Dioscorides were stalactites containing but little alum and consisting 
 chiefly of calcareous earth, which, in certain proportions* will hereafter appear 
 to be a very useful addition for most of the colours depending on an aluminous 
 basis. Nature, however, does produce some, though but little, crystallised 
 alum., particularly in Egypt and some parts of Asia, and it probably was in this 
 state that its good effects in dyeing had been first observed, before mankind 
 were led to the means and operations since employed for separating and 
 collecting it from the various aluminous ores. Bergmann says that ' the 
 factitious salt which is now called alum was first discovered in the eastern 
 countries;' and that 'among the most early works established for the prepa- 
 ration of alum we may justly number that of Roccho, a city in Syria, now 
 called Edessa : hence the appellation of roche alum (see vol. i., p. 339, of the 
 English translation of his Essays).' He adds that ' Bartholomew Perdix, or 
 Pernix, a merchant of Genoa, who had been at Roccho, discovered the matrix 
 of alum in the island of Ischia, about the year 1459, and established a 
 manufactory there; at the same time, John de Castro, who had visited the 
 
 * Menjoires Concernants l'Histoire, les Sciences, les Arts, les Mceurs, &c, des Chinois. 
 
INTRODUCTION. 5 
 
 manufactories at Constantinople, discovered a matrix at Tolfa, by means of 
 the Ilex aquifolium, which he had also observed to grow in the adjacent 
 mountains of Turkey, and his opinion was confirmed by the taste of the stones. 
 The attempts made by the Genoese at Viterbium and at Volaterre succeeded 
 extremely well ; the preparation of alum in Italy soon increased wonderfully 
 fast, &c. The first manufactory in England was established in the reign 
 of Elizabeth, at Gisborough, by one Thomas Chaloner.' "—Bancroft, " On 
 Permanent Colours." 
 
 When Italy was overrun by those barbarous nations who came from the 
 north-east of Europe, the progress of all arts and sciences and of all human 
 industry belonging to advanced civilisation was stopped, and remained so 
 during at least five centuries, except in a small portion of Spain. Here the 
 so-called Saracens succeeded in establishing a settled state of society, and, as 
 evidenced by the records they left, attained high proficiency in manufacturing 
 arts, such as paper making, sugar refining, and the extraction of dyes from 
 native vegetable produce. They were, doubtless, acquainted with the process 
 of dyeing the so-called Turkey red, as the means of producing that dye on 
 tissues were known at the time at Adrianopolis, in Turkey. 
 
 In the Middle Ages, the Jews were perhaps the greatest dyers. During what 
 is often called the Revival Period of Literature and Science, to wit, the end of 
 the 12th and beginning of the 13th centuries, the Republic of Florence became 
 not only the seat of civilisation, but of a thorough revival of industry and 
 manufacture, especially as regards dyeing. 
 
 "According to M. Berthollet, whatever knowledge the Greeks and Romans 
 had derived from others or acquired from their own observations appears to 
 have been in a great degree lost about the 5th century, when scarce any traces 
 of science, industry, or humanity were left in what was then called the Western 
 Empire ; a little, however, did remain, and it was afterwards preserved in Italy, 
 where the Venetians contrived to import many oriental productions and manu- 
 factures, which, by affording new means, as well as new objects of imitation, 
 contributed greatly to revive the arts. 
 
 " The first collection of processes used in dyeing was published at Venice in 
 1429 under the name of " Mariegola del'Arte de Tintori," of which another 
 edition, much improved, appeared in 15 10 ; and from this an individual named 
 Giovanne Ventura Rosetti, who travelled into different parts of Italy and the 
 neighbouring countries, to learn the methods and means employed in dyeing, 
 composed, and in 1548 published, a work under the title of " Plictho del'Arte 
 de i Tintori, &c," which has been supposed to have contributed more than any 
 other to the improvements afterwards made in that art. In this work, how- 
 ever, there is no mention of either indigo or cochineal, which M. Berthollet 
 therefore concludes were not at that time employed by the Italian dyers. This 
 appears to have been the work which, at a meeting of the Royal Society on the 
 30th of April, 1662, Mr. Haak was desired to translate into the English lan- 
 guage (see Dr. Birch's " History "). That learned body had, upon its first insti- 
 tution, bestowed some attention to the subject of dyeing ; and on the same day 
 Sir William Petty, one of its earliest and most active members, in consequence 
 of a previous request from the Society, brought in "An Appendix to the His- 
 tory of the Common Practices of Dyeing," which was afterwards printed in 
 Dr. Spratt's " History of the Royal Society," and seems to have been the first 
 

 6 DYEING AND CALICO PRINTING. 
 
 account published in the English language of the means and operations used 
 by dyers. Nearly two years afterwards, viz., March 30th, 1664, Mr. Boyle 
 presented to the Royal Society his " Experiments and Considerations touching 
 Colours ;" and on the 10th of August following it was ordered by the Society 
 1 that the way of fixing colours should be recommended to Mr. Howard, Mr. 
 Boyle, and Dr. Merrit.' These, and especially the first two, were among the 
 most distinguished members of the Society ; but it does not appear that 
 they were able to do anything deserving of notice, in consequence of this 
 recommendation. However, at a meeting of the Society on the nth November, 
 1669, that very ingenious and useful member, ' Mr. Hooke, produced a piece of 
 calico stained after the way contrived by himself, which he was desired to 
 prosecute in other colours besides those that appeared in this piece (Birch's 
 " History of the Royal Society," vol. ii., p. 401) ; ' and, accordingly, on the gth 
 of the following month, ' Mr. Hooke produced another specimen of staining 
 with yellow, red, green, blue, and purple colours, which he said would endure 
 washing with warm water and soap.' But from this time it does not appear 
 that anything considerable was done for nearly the space of a century, by men 
 of science in this kingdom, towards improving the arts of dyeing and calico 
 printing, they being probably discouraged by the difficulties which, from the 
 very imperfect state of chemical science, must have occurred in every attempt 
 to improve upon what the dyers were able to perform without any principle or 
 theory. In France, however, the minister Colbert, anxious to extend the 
 commerce and manufactures of that country, turned his attention particularly 
 to the art of dyeing, with a view to amend, as well as to obviate, frauds in the 
 practice ; and for these purposes an " Instruction Generate pour la Teinture des 
 Laines et Manufactures de Laine de toutes Nuances, et pour la Culture des 
 Drogues ou Ingredients qu'on Emploie" was prepared under his immediate 
 direction, and published in 1672. This, however, was not intended merely to 
 inform, but as a legislative act to control the dyers in their operations. It 
 divided them into two classes ; the one, dyers " en grand" were confined to 
 the colours deemed lasting, while the dyers " en petit telnt" were allowed only 
 to give those which were considered as fugitive ; and the drugs to be employed 
 in each branch were also particularly specified, and the dyers in each prohibited 
 from using or having in their possession any of the drugs allotted to the other. 
 Restraints of this kind, though intended to prevent frauds, must have operated 
 as checks upon future improvements if the government had not encouraged 
 useful discoveries in this art. first by offering rewards, and afterwards by 
 appointing those eminent chemists, Dusay, Hellot, Macquer, and Berthollet, 
 in succession, to superintend and improve the arts connected with chemistry, 
 and more especially that of dyeing. 
 
 " Dusay appears to have been the first who entertained just conceptions of 
 one of the causes of the adhesion of colouring matters to stuffs when dyed ; 
 viz., that which depends on an affinity or attraction subsisting between such 
 matters and the fibres or substances of the dyed stuffs. He also noticed the 
 difference in the degree of attraction which different substances, as wool and 
 cotton, exert upon the same colouring matters, and which he found so great 
 that a skein of each having been in an equal degree subjected to the means 
 and operations commonly employed for dyeing scarlet, the woollen yarn was 
 found to be fully and permanently dyed of that colour, while the cotton 
 
INTRODUCTION. 
 
 retained all its former whiteness. He appears, however, to have had no con- 
 ception of the other and more important cause of the permanency of adjective 
 colours — viz., that which arises from the interposition of a suitable basis 
 possessing a particular attraction both for the colouring matter and for the 
 dyed substance, and thereby acting as a bond of union between them ; nor did 
 his successor, Hellot, ever approach nearer to the truth on this subject. He 
 (Hellot) fancied that he could discover in every dyeing process some means by 
 which sulphate of potash might be formed ; and this neutral salt not being 
 readily soluble in cold water, nor affected by air or light, he conceived the art of 
 dyeing to consist in first dilating the pores of the substance to be dyed, so as 
 to procure a copious admission of colouring matter, divided by a suitable 
 preparation into atoms, and then wedging or fastening these atoms within the 
 pores of the dyed substance by the small particles or crystals of this difficultly 
 soluble neutral salt. Upon this mechanical hypothesis he supposed that alum 
 became useful in dyeing, not by the pure clay or alumina which it contains, 
 and which alone contributes to fix any colouring matter, but only by furnishing 
 sulphuric or vitriolic acid to assist in forming the sulphate of potash, which 
 was to perform this important function of wedging or fastening the colouring 
 atoms ; though, if he had brought this visionary hypothesis to the test of 
 experiment, as might have been easily done, he would have found, not only 
 that no sulphate of potash existed in many cases where he supposed it to pro- 
 duce such important effects, but also that, even if intentionally formed and 
 employed for this purpose, it possessed no power whatever of fixing any 
 colouring matter yet known. But, though nothing could be more groundless 
 than the theory, the learned in all countries appear to have been satisfied with 
 it for a considerable length of time, it being always less troublesome to believe 
 than to make experiments. 
 
 "According to Mr. Henry of Manchester, M. Keir, the ingenious translator 
 of Macquer's ' " Chymical Dictionary," appears to have been the first who sus- 
 pected that (in dyeing) the earth of alum was precipitated, and in this form 
 attached to the material prepared or dyed.' Some time after this, Mr. Henry 
 published an interesting paper in the third volume of the " Memoirs of the 
 Manchester Society," " On the Nature of Wool, Silk, and Cotton as Objects 
 of the Art of Dyeing, on the Various Preparations and Mordants requisite for 
 these Different Substances, and on the Nature and Properties of Colouring 
 Matter, &c," a paper replete with useful information and ingenious ideas." — 
 Bancroft, " On Permanent Colours." 
 
 Trustworthy authorities state that no less than two hundred dye-works existed 
 at Florence about the end of the 14th century. The application of colours 
 derived from lichens, and more especially the species known as " Rocella," 
 was so extensively and successfully carried out that, in order to prevent the 
 process being divulged, a guild was formed which obtained the name of 
 " Rocellarii." 
 
 The discovery of America opens a new era in the progress of dyeing. Many 
 new dye-stuffs were then brought from that country into Europe, among which 
 logwood, cochineal, annatto, and brazil-wood may be mentioned. 
 
 The use of tin salts as mordants was discovered about the middle of the 
 17th century by the Dutch chemist, Cornelius Drebbel, who found that they 
 yielded a magnificent colour with cochineal. Drebbel's son-in-law, who 
 

 8 DYEING AND CALICO PRINTING. 
 
 obtained from him considerable information upon the subject of dyeing, set up 
 large dye-works at Bow, near London, in 1643, and successfully carried on an 
 extensive business for a number of years. 
 
 The journeys to India made by the Portuguese and the inhabitants of the 
 Netherlands early in the 17th century had the effect of again introducing 
 indigo to the notice of European nations as a substitute for woad as a blue dye 
 material. The farmers who cultivated the latter plant felt their interests 
 injured by the introduction of indigo, and acccordingly several governments, 
 including our own, in the time of Elizabeth, prohibited its use, and large 
 quantities were destroyed. A similar measure was enacted against logwood. 
 In consequence of this prohibition, woad was still used instead of indigo long 
 after the re-importation of the latter; and even as late as the end of the last 
 century the dyers' foremen of Niiremburg were compelled to take an oath 
 before the Syndic of that town to abstain from the use of indigo and employ 
 woad only, as being the orthodox and genuine colour. However, notwith- 
 standing the oath, when Niiremburg was taken and pillaged by the French, 
 about 1798, large quantities of indigo were found in the town. The progress 
 made during the 18th century in dyeing, as well as in printing calico, is too 
 varied and extensive to be specifically alluded to here ; suffice it to say that in 
 France especially it was very great. It is more particularly from France that 
 most other nations of Western Europe originally obtained those preparations 
 of large establishments and manufactories which have now become so numerous, 
 especially in Great Britain. Political commotions, for instance the repeal of 
 the Edict of Nantes, drove a number of industrious and skilful people from 
 France at an earlier period ; they took refuge in England, the Netherlands, 
 and Switzerland, and carried with them the knowledge of industrial art already 
 practised in their native country. The great discoveries made in chemistry 
 during the latter part of the last century have greatly improved and extended 
 the application of dyes to woven fabrics, whilst the employment of steam as a 
 motive power presents increased facilities for practising the art. 
 
(9) 
 
 CHAPTER I. 
 
 THE ART OF DYEING IN ITS RELATION TO CHEMISTRY. 
 
 TV TOST operations in dyeing (the word being used here in a wider sense as 
 applying also to the allied arts of bleaching and printing) may be con- 
 sidered as directly chemical, and the mechanical appliances as so much 
 apparatus intended to facilitate or regulate the chemical action taking place 
 between the fibre, the mordant, and the colouring matter. As this action 
 varies in kind or degree for every colour produced, it may be readily granted 
 that few of the arts are more intimately connected with chemistry, or depend 
 more upon chemical laws, than dyeing. 
 
 Most of the recent improvements in dyeing have originated on the Continent ; 
 garancine, garanceux, with other preparations of madder, the application of 
 albumen and caseine, and the introduction of murexide, picric acid, and 
 modified archil colours, are all due to France ; and the best shades of the red 
 modification of the aniline colours have been produced in Vienna. The dis- 
 covery of aniline dyes is, however, due to Mr. Perkin, who was the first to 
 manufacture them in a practicable form. Fuchsine was discovered some 
 months later by Verguin, who was the adapter of the discovery of Hofmann 
 that bichloride of carbon gave a red colour with aniline. The number of 
 colouring matters possessed by dyers is very limited ; there is only one fast 
 red upon cotton — madder, and only one fast blue — indigo. With regard to the 
 artificial production of such substances as are formed by the vital activity of 
 the plant from which madder is obtained {Rubia tinctorum), as alizarine, the 
 most permanently active colouring principle of that substance has been produced 
 by Messrs. Broenner and Messrs. Graebe and Liebermann. There can be little 
 doubt that Graebe's alizarine will find many uses ; its employment will be 
 merely a question of cost. Concerning the state in which the colouring 
 matters of madder exist in the plant, we know that alizarine is not contained 
 as such in the root, but is formed by the action of acids or ferments on a 
 glucoside whose chief properties and composition have been ascertained. 
 That alizarine is the essential constituent of madder colours is proved by the 
 fact that the finest and purest madder colours (Turkey red, madder pink, and 
 purple) contain no other colouring matter in combination with the mordants ; 
 and there is little doubt that alizarine will form as efficient a substitute for 
 madder as indigo has for woad. At the same time it d«es not follow that the 
 other colouring matters of madder are useless. 
 

 io DYEING AND CALICO PRINTING. 
 
 All colours are produced indirectly by colouring substances, and owe their 
 origin to light. We perceive objects and colours by means of rays of 
 light proceeding from them to the visual organs. Light, as it proceeds from 
 the sun, contains the elements of all colour, and can be analysed or decom- 
 posed by a glass or crystal prism, which will separate it into seven different 
 hues. Only three of these appear essential, the others being produced by 
 combinations of these three. The three primary colours are red, yellow, and 
 blue, their union producing green, violet, orange, and indigo. The chemical sub- 
 stances, prussian blue and vermillion for instance, are not in themselves blue or 
 red, but appear so because they possess the power of decomposing light. Prus- 
 sian blue absorbs and destroys the red and yellow rays, leaving only the blue 
 visible; while vermillion, on the contrary, nullifies the blue and yellow rays 
 and reflects the red ones. It is the same with all colours ; a colouring matter 
 should be looked upon as a body having the power of reflecting undulations of 
 a certain speed ; colour cannot exist in solids, but it is an action of the undula- 
 tions of the luminiferous ether on the organs of sight. All colours are alike in 
 the dark ; but they are not always the same in daylight as in artificial light, 
 and chemical substances may change colour, or lose it altogether, without 
 their chemical composition being affected. Effects of colour may be produced 
 by light in two different ways, either by reflection from a surface which appears 
 coloured — the more common phenomenon — or by transmission of light through a 
 coloured transparent body, such as stained glass or liquid. Some substances 
 vary in colour when seen by transmitted or reflected light ; crystals of 
 murexide are green by reflected and red by transmitted light, and there are a 
 number of similar cases. This is an additional proof that colour is not due 
 to a body itself, but to the position or physical arrangement of its particles. 
 
 It is not intended to enter into any other details of either physics or 
 chemistry; numerous excellent works exist upon. those subjects, and a brief 
 resume would necessarily be too incomplete to be of any real utility. 
 
 Water — Tests for Impurities. 
 
 This fluid is of no less importance from an industrial and manufacturing 
 point of view than in its relations to man and the whole organic creation. 
 Although it exists in great abundance and covers by far the largest part 
 of the surface of our globe, it is never met with in a state of absolute purity 
 it must be remembered that we are now considering water more especially in 
 relation to dyeing and printing. Perfectly pure water, even if it could be 
 obtained upon a large scale without much cost and trouble, would not in all 
 instances answer the practical purposes of the dyer and printer. Experience 
 teaches that in madder dyeing, for instance, especially with some preparations 
 of that substance, the presence of carbonate of lime in water is considered to 
 be very advantageous. 
 
 The following substances have been detected in natural waters: carbonic, 
 nitric, nitrous, sulphuric, sulphurous, phosphoric, boracic, silicic, hydrochloric, 
 and hydrosulphuric acids. The presence of the following basic substances, 
 potassa, soda, lithia, ammonia, strontia, baryta, lime, magnesia, alumina, 
 oxides of iron, manganese, zinc, copper, lead, silver, arsenic, nickel, and 
 cobalt has been ascertained. Chlorine, bromine, iodine, fluorine, sulphur, 
 and carburetted hydrogen have also been discovered in natural waters. 
 
WATER— ITS IMPURITIES. n 
 
 Nitrogen and oxygen, in varying proportions, are found in all waters. 
 By far the greater number of the substances here mentioned occur, how- 
 ever, in very minute quantities, or are met with only under special conditions, 
 as in the case of free sulphuric or hydrochloric acid, which is found in only 
 a few cases, as in volcanic regions. Such metals as copper, zinc, lead, and 
 others occur only in water pumped up from mines, or in isolated cases where 
 small rivulets or springs happen to pass through lodes of metallic ore. The 
 saying of Hippocrates concerning water — " Such as the soils are, so are the 
 waters which run through them " — the result of patient and shrewd observa- 
 tion, is as true now as it was nearly twenty-five centuries ago. Water, as a 
 general solvent, aided, moreover, by the mechanical effect of its motion, is 
 capable of keeping not only in solution but also in suspension a large quan- 
 tity of substances, among which organic matter holds a prominent place. 
 
 The mineral substances most frequently found in river, spring, and well 
 water are as follows : — 
 
 Lime, combined with carbonic acid, mechanically suspended as chalk, or 
 held in solution by an excess of carbonic acid or with other acids. 
 
 Magnesia occurs as carbonate of magnesia kept in solution in carbonic 
 acid, and also as sulphate and chloride of magnesium. 
 
 Potash and Soda are never absent from natural waters, they are most 
 frequently combined with chlorine, but also with sulphuric acid ; in some, 
 especially mineral waters so-called, they occur not unfrequently as carbonates. 
 
 Iron occurs in natural waters (mineral waters excepted) in only very small 
 quantities, and generally as carbonate of the protoxide held in solution by 
 carbonic acid ; it is, however, by no means a rare constituent, as sulphate of 
 the protoxide, in water discharged from mines and coal pits. When this 
 water gets into rivers it is always precipitated by the constantly present 
 alkaline substances in, one may say, all river waters. 
 
 Arsenious and Arsenic Acid have been detected in many of the natural 
 waters of France and at baths in Germany in appreciable quantity ; the latter 
 very rarely, the former more frequently than is commonly supposed ; these 
 waters are used daily by a large number of the inhabitants of those countries, 
 but without producing any apparently bad effect upon their health. 
 
 With the exception of organic matter, those substances in water which 
 chiefly concern the dyer are lime, iron, and magnesia; the rest are of little 
 importance. Lime occurs in water chiefly as carbonate and sulphate ; when 
 it is present as carbonate it is held in solution by carbonic acid, and as that 
 gas is driven off when water is boiled it will of course become turbid, even if its 
 original bulk, which should be measured previous to ebullition, be kept up as 
 it should be by the addition of distilled water. Another and a better method 
 of preventing the water losing bulk whilst boiling is to conduct the operation 
 in a flask to which a long tube is attached, so that the steam may be condensed 
 and caused to run back into the flask. 
 
 The ebullition should be kept up for some length of time, varying according to 
 the quantity of water, but for not less than an hour, and the water will then be 
 seen to become more or less turbid in proportion to the quantity of carbonate 
 of lime contained in it. It may be easily rendered clear again by adding a 
 few drops of hydrochloric or acetic acid, which dissolve the carbonate of lime 
 with effervescence. 
 
MH^^^^^^M 
 
 
 I2 DYEING AND CALICO PRINTING. 
 
 To enter into particulars concerning the analysis of water or the detection 
 of the various salts which it may contain would consume too large a portion 
 of our space; readers requiring further information on the subject will find it 
 in works on analytical chemistry : it is here intended briefly to point out the 
 different actions of the carbonate and sulphate of lime in dyeing. Both are 
 injurious to bright colours, but not so to dark or sombre hues, unless present 
 in very large quantity; carbonate of lime is even considered rather ad- 
 vantageous in madder dyeing, especially with certain kinds of madder, and 
 ground chalk is frequently added to the water before using it, to make up any 
 deficiency. Sulphate of lime in any quantity is injurious in dyeing with 
 madder or with any dye procured from wood, causing waste of colouring 
 matter with inferior results. The production of good brilliant light shades is 
 incompatible with the use of water containing sulphate of lime. Magnesia in 
 the state of chloride or sulphate does no harm provided it be not easily 
 convertible into carbonate by boiling, which can readily take piace should much 
 carbonate of lime be present in the water ; but if it should exist as car- 
 bonate or be converted into it during dyeing it is very detrimental, as it com- 
 pletely prevents the dyeing of certain colours and spoils the appearance of 
 others. Madder, when mixed with one-fiftieth of its weight of calcined 
 magnesia will not dye at all, and is spoiled by the addition of one part per cent. 
 In the north of England it is sometimes present in quantity sufficient to affect 
 madder colours ; however, it is seldom present in water in sufficient quantity to 
 be injurious. 
 
 Iron is found in almost all natural waters, but not usually in very 
 large quantities, except in mineral waters. As has already been stated, it 
 generally occurs as carbonate of the protoxide held in solution by excess of 
 carbonic acid. Its presence, whether in large or small quantities, is very 
 injurious to dyeing operations, and we therefore give a good practical test for 
 its detection. If a single drop of tincture of logwood or strong logwood 
 liquor be added to a wineglass of water perfectly free from iron, it will assume 
 a sherry or claret colour, according to the quantity of lime present ; but should 
 the water contain iron, it will turn blue, blue-black, and finally inky-black, in 
 proportion to the amount of that metal held in combination. This test 
 requires to be examined immediately, for if the glass vessel in which it is 
 made be left exposed to the air the logwood turns darker, and might perhaps 
 be supposed to indicate iron in cases where none existed. Another precaution 
 is necessary : the water to be tested should be freshly drawn, for should it 
 have been standing for some time, even in well closed bottles, the iron is pre- 
 cipitated as insoluble oxide, in which case the change of colour by logwood 
 no longer takes place. The influence of water impregnated with iron upon 
 dyeing is very marked — pinks become drabs, and reds are turned into dull 
 browns and chocolate colours, whilst, if the quantity of iron present be large, 
 it combines with the colouring matters, and the cloth receives none of them, 
 or only a small proportion. Fortunately for the dyers, the simple action of 
 the oxygen of the air readily decomposes the salts of the protoxide of iron as 
 met with in natural waters and turns them into peroxide of iron, so that 
 water containing that metal need not necessarily be rejected for dyeing 
 purposes. Where larger quantities of iron are present the same effect may be 
 produced by aerating the water, and if possible heating it by means of waste 
 
WATER— ITS IMPURITIES. 
 
 13 
 
 steam whilst standing in suitably-constructed vats. A precipitate of peroxide 
 of iron is thus formed, insoluble in water and neutral or alkaline liquids. With 
 the exception of mineral waters, properly so called, salts of potash and soda 
 are seldom present as carbonates in sufficient quantity to produce any marked 
 effect upon dyeing, whilst their existence as chlorides or sulphates is unim- 
 portant; and, moreover, the quantity of any of these salts usually found in 
 water is but small. Silica is frequently met with in water, but is not 
 usually considered to be injurious in dyeing. The experiments of Mr. O'Neill, 
 of Manchester, tend to prove, however, that pure hydrated silicic acid is 
 injurious in madder dyeing, although not strikingly so. 
 
 Organic Matter in water, that frightful bete noir to so many people, is by no 
 means to be overlooked in its relations to dyeing and printing ; it is especially 
 detrimental to bleaching and clearing. Crenic and apocrenic acids, the various 
 forms and modifications of humin, ulmin, and that series of substances which 
 may be generalised as peaty matter, are often decidedly deleterious in either 
 dyeing, bleaching, or clearing, imparting a yellow tinge not easily removable. 
 These forms of organic matter may be tested for by mixing about a pint of 
 the water with half a fluid ounce of a perfectly clear filtered solution of hypo- 
 chlorite of lime (bleaching-powder), sp. gr. roi4, and heating in a glass flask 
 to about 160 F. (71 C.) Should the fluid so treated become yellow and 
 precipitate a buff-coloured deposit, the water is unfit for clearing goods by the 
 old method. It may, however, serve for clearing by the padding machine and 
 steam box method, as that does not require nearly so much water. Dyeing 
 and printing works are seldom so situated as to be able to use water without 
 some purifying process. The most common purifying agents are exposure to 
 air and light, and the separation of suspended matters by filtration ; but 
 there is one method to which we here call attention by which the worst water 
 may be greatly improved even when largely impregnated with animal and 
 vegetable matter. This consists in adding successively to each 1000 
 cubic metres ( = 35,316 cubic feet, or 220,096 gallons) of water, which 
 should be contained in a suitable tank, about 67 lbs. of dry perchloride 
 of iron, and 186 lbs. of crystallised carbonate of soda, both previously 
 dissolved in as pure water as can be obtained, to the volume of about 
 220 gallons (35 cubic feet). By this process most of the organic matter is 
 removed, and some of the lime salts greatly lessened in quantity, being carried 
 down with the flocculent sediment ; this begins to fall slowly immediately 
 after the addition of the iron and soda, which should be well mixed with the 
 water by vigorous stirring. The chloride of sodium added by this process 
 amounts only to ^jjcnoth, too small a quantity to be in any way deleterious. 
 
 Water has not the same degree of solvent action upon all substances, and some 
 remain insoluble under its influence ; as a rule hot water dissolves more 
 substance than cold, and does so more quickly, but the excess dissolved when 
 hot frequently separates in crystals when cooled. This is a point which 
 deserves notice, for a liquid which, when warm, is of the proper strength, 
 may be too weak when cold. This happens very frequently with solutions of 
 salts that are but moderately soluble, such as chlorate, bitartrate (so-called 
 cream of tartar), and sulphate of potash. Crystallisation is also troublesome 
 in steam colours, which though good enough when freshly made, become filled 
 with small crystals on cooling, and work rough in the machine. 
 

 
 14 
 
 DYEING AND CALICO PRINTING. 
 
 Boiler Incrustations. 
 
 As water is used for the production of steam a word may be said here con- 
 cerning boiler incrustations. These are chiefly due to the salts of lime 
 (carbonate and sulphate) contained in water becoming deposited from it by 
 evaporation and forming a hard stony crust inside the boilers. As the com- 
 position and quantity of mineral substances held in solution in water vary 
 according to the water itself, it is obvious that no general specific against 
 boiler incrustations can be given. The number of substances proposed for 
 this purpose is too large to be enumerated ; suffice it say that the action of 
 some is simply mechanical, interposing such salts between the particles of the 
 lime salts as will prevent their forming a solid crust, while others act chemically 
 by bringing about double decomposition, and, lastly, several organic substances, 
 such as sawdust, spent tan, potatoes, molasses, catechu, and others appear to 
 act partly mechanically, partly chemically, although it is not possible to 
 specify precisely how and why. 
 
 Rain water, which itself is too pure to give rise to these incrustations, cannot 
 be used alone for boiler purposes, for it has been found to exert a highly 
 corrosive action upon the iron plates and fittings. It can, however, be 
 advantageously employed in conjunction with hard spring and river waters, 
 and has the effect of diminishing the incrustation merely as the result of 
 dilution. The drain pipes leading from the roof of the factory may be placed 
 in connection with the tank or well from which the supply of water is drawn 
 for the boilers. It will be seen hereafter that the same remedy is efficient 
 both as a means of preventing incrustation and obviating corrosion, and that 
 by using one of the alkaline substances about to be specified this twofold 
 advantage may be secured. Iron will not rust when immersed in water con- 
 taining a mere trace of caustic alkali, and it is a common observation that 
 the iron vessels used in the preparation of potash and soda remain for any 
 length of time free from all appearances of rust. This singular property is no 
 doubt susceptible of important applications; amongst them may be mentioned 
 the better protection of iron ships from the attack of bilge water, of hydraulic 
 rams, smiths' tools, and other objects liable to be placed at times under the 
 influence of water. Some forms of " surface condensers " become quickly 
 corroded in consequence of the purity of the water accumulating in them by 
 the process of distillation, and a small dose of caustic alkali is then useful as 
 a means of protection ; the engine cylinders are also to some extent preserved 
 when alkaline anti-incrustation fluids are intioduced into Lhe boiler, for the 
 minute quantity which is carried forward mechanically in the form of spray 
 mixed with the steam suffices to preserve the iron ; but a tendency to 
 priming undoubtedly results from a too liberal use of soda or other alkali 
 in the boiler. It will in practice be found easy to adjust the proportion of 
 this ingredient so as to secure immunity from corrosion and incrustation, and 
 at the same time avoid the tumultuous kind of ebullition known as " priming." 
 In all cases it is advisable to carry out a rigid system of inspection, and it is 
 only in the way of saving fuel and labour that the application of boiler-fluids 
 is to be recommended. 
 
 Much benefit has often resulted from a coating of coal tar, or " dead o 1," 
 applied to the interior surfaces below the water line when the boiler is oren 
 
WATER— ITS IMPURITIES. 
 
 *5 
 
 for cleaning and inspection. These will tend very considerably to lessen the 
 adhesion of calcareous crusts, and are in no way affected by the boiler fluids in 
 common use. 
 
 Soda crystals and caustic soda may be used with great success in boilers to 
 effect the immediate precipitation of the lime salts, and they act by throwing 
 down a finely divided form of carbonate of lime, which in turn furnishes nuclei 
 for the deposition of subsequent accretions both of the carbonate and sulphate, 
 so that they are prevented from crystallising upon the walls of the boiler. A 
 granular mud is thus formed, which subsides quickly, and may be for the most 
 part got rid of through the " blow off" cock, which should be opened for this 
 purpose two or three times every day, and run out with as little water as 
 possible. 
 
 The use of caustic soda has undergone a thorough trial in the boilers 
 of the Royal Arsenal, Woolwich, and we are enabled to give the following 
 general instructions regarding its use, which are based upon an experience 
 of upwards of ten years. The caustic soda should be dissolved in water 
 so as to make a concentrated solution of sp. gr. 1300. This being per- 
 fectly miscible with water may be introduced into the boiler with the 
 feed-water at any time when, from the pressure of steam, it may not 
 be convenient to pass it through the safety-valve or other openings in 
 the boiler. But when the steam is down there is no difficulty in introducing 
 the prescribed dose by using a tin funnel with flattened aperture to pass it 
 through the safety-valve, or a tubular arrangement with double cocks will 
 answer at all times. Half a gallon per diem is the average quantity found 
 sufficient for a 20-horse power stationary boiler working with Thames water for 
 ten hours in the day. If the water should happen to be unusually hard a larger 
 dose may be employed, but it would not be expedient to add in one charge 
 more than the day's consumption. Locomotive and multitubular boilers have 
 been worked successfully with caustic soda, and it is here that the importance 
 of using anti-incrustation fluids makes itself most apparent. 
 

 ■ 
 
 (i6) 
 
 CHAPTER II. 
 
 TEXTILE FIBRES AND TISSUES MADE THEREFROM. THICKENINGS AND 
 PLASTIC MORDANTS. 
 
 T)EFOR£ proceeding with an examination of those substances which serve 
 -*-^ to impart colour to woven tissues, we will devote a portion of our space 
 to the study of textile fibres. Any substance capable of yielding a certain 
 continuous and uninterrupted length of filamentary matter may be called 
 textile fibre, and the number of such substances is large, but the proportion 
 suitable for application to weaving purposes is limited, and only a few can 
 be employed alone in the fabrication of tissue. Fibres are divided according 
 to their origin into three groups — i. Mineral; 2. Vegetable ; and 3. Animal. 
 Up to the present time the artificial production of fibres has not succeeded, 
 and those most useful to man are produces of the vital activity of plants and 
 animals. 
 
 Mineral Fibres. 
 
 The only mineral fibre we are acquainted with is asbestos or amianth, and 
 although it cannot be dyed it may be interesting to refer briefly to it here. 
 It is a polysilicate composed chiefly of lime, magnesia) and small quantities 
 of alumina and iron. It is related to pyroxen ; the percentage composition of 
 the Tarantaise variety is expressed as follows : — Silica, 58*20 ; alumina, 0*14 ; 
 protoxide of iron, 3*08; protoxide of manganese, 0*21 ; magnesia, 22'io ; 
 Lime, 15*55 i water, 0*14. This variety is met with in very long, well-defined, 
 glossy, and silky-looking filaments in that portion of the ancient Duchy of 
 Savoy called La Tarantaise ; the same variety also occurs in Corsica, where it 
 was used by the celebrated philosopher Dolomieu for packing the minerals 
 collected by him during his sojourn in that country. 
 
 Asbestos can be woven into tissues, especially if a flax fibre is worked up with 
 it; its use is, however, very limited in the present day. The ancients who 
 were in the habit of burning their dead used a tissue made of asbestos in 
 order to collect the ashes of the dead bodies without admixture of the ash of the 
 combustible used during the process of burning. The name " amianth," which 
 signifies " undefiled" — that is, pure and unchangeable in the fire — has been 
 given to it in consequence of its being incombustible. Tissues made of 
 asbestos are at present practically used in Russia only. The fire brigade of 
 St. Petersburg are provided with gloves and other portions of wearing apparel 
 made of this substance in Siberia ; it has also been used in the manufacture 
 of paper in France and America. 
 
CELLULOSE. 
 
 *7 
 
 Mineral Thickenings. 
 Only two mineral thickenings are at present employed, namely, kaolin and 
 pipe-clay ; these are generally used mechanically as resists. Pipe-clay and 
 torrefied starch are employed to print complicated patterns, especially in 
 block printing. The former is also used as a resist composition applied to parts 
 of a fabric to prevent the deposition of colour or mordant upon those parts. 
 By its use the quantity of gum required as a thickening is considerably 
 reduced. Steam colours thickened with pipe-clay lose from 35 to 50 per cent 
 of their intensity when applied to woollen tissues, but with cotton fabrics 
 little loss is experienced. Before its use pipe-clay should be carefully washed 
 and deprived of all coarse particles by being made to pass through a fine sieve, 
 and then allowed to deposit slowly from water ; it should be free from oxide 
 of iron. Kaolin is used in a similar manner, but is more expensive. 
 
 Vegetable Fibres. Vegetable Thickenings. 
 
 The most important vegetable fibres, cotton, flax, hemp, aloe fibre, New 
 Zealand flax (the fibre of the Phormium tenax), jute (also called Bengal 
 hemp), rame, woody fibre, and pine-apple fibre, are all composed chiefly of 
 cellulose mixed with different foreign substances, sometimes called collectively 
 incrustating matter. Under this term is included colouring matter and a 
 peculiar substance possessing organised structure and known as suberine. As 
 there exists a striking analogy between cellulose and vegetable thickenings, it 
 is clear that an examination of the former leads directly to that of the latter. 
 
 Cellulose. 
 
 The study of the organs of plants teaches us that they are composed of a 
 number of cells and hollow vessels varying greatly in form and shape. 
 These vessels are all filled either with air, essential oils, starch, or an endless 
 variety of organic and inorganic substances, among which may be instanced 
 some peculiar active principles, sugar, fatty matter, and caoutchouc ; but the 
 main portion of plants, and the wood even of trees, consist of cellulose in a 
 state more or less pure. This substance forms the connecting link between the 
 animal and vegetable kingdom, for it also constitutes the cutaneous envelope 
 and muscular system of the lowest form of animal life. As a type of perfectly 
 pure cellulose we may take clean cotton fibre after it has been thoroughly 
 bleached. In that state it is a colourless, inodorous, tasteless substance, in- 
 soluble in and not adted upon by water, alcohol, ether, benzol, &c. Its 
 sp. gr. is equal to i'525, water being i - ooo; and its chemical composition may 
 be expressed by the formula C6Hi 5 or Ci 2 Il2oO IO ; it therefore belongs to 
 the carbo-hydrates, or substances in which hydrogen and oxygen are contained 
 in the proportion in which they exist in water. Pure cellulose may be 
 heated to 446° without alteration, but if subjected to higher temperature it 
 becomes brown-coloured and decomposed. When submitted to destructive 
 distillation it yields water, carbonic acid, carburetted hydrogen, methylic 
 alcohol, acetic acid, and creosote, with an abundant residue of porous 
 charcoal. It burns readily with proper access of air, emitting but little smoke, 
 and no particular smell. When perfectly pure or even nearly so, as in the 
 form of well made paper, cellulose is quite indestructible by the action of 
 
i8 
 
 
 DYEING AND CALICO PRINTING. 
 
 the air, but when mingled intimately with nitrogenised and especially 
 albuminous substances, as in wood, the case is different. These substances 
 are very prone to decompose, and when once their molecules are set in 
 motion that motion is gradually imparted to the entire structure. The result 
 is a slow combustion, which, assisted by air and moisture, soon destroys the 
 substance, converting it by a series of metamorphoses, and by a process 
 called by Liebig eremacausis, into a variety of organic compounds, including 
 humin, ulmin, and humic and ulmic acids. According to M. Pasteur, the rotting 
 of wood is due to the presence of infusoria which feed upon the albuminous 
 substance contained in it ; but as this theory has been the subject of much 
 controversy we will not enter upon it here. Very dilute acids exercise no 
 marked action upon cellulose even at boiling heat, but the a&ion of con- 
 centrated acids is entirely different and very important from a practical point 
 of view. 
 
 When pure cellulose, cotton for instance, after being thoroughly bleached, 
 is placed in concentrated phosphoric or sulphuric acid at the ordinary 
 temperature, it becomes disintegrated, and dissolves, colouring the acid. It 
 changes into a viscous mass consisting of dextrine, which has the same 
 chemical composition as cellulose ; the only real change is, therefore, a 
 molecular change. If the acid solution is largely diluted with water and then 
 boiled, the dextrine fixes the elements of the water and is converted into 
 glucose. If cellulose be treated with moderately diluted nitric, sulphuric, or 
 hydrochloric acids and subject to the action of heat, disintegration occurs, and 
 the result is a somewhat thickish mass apparently insoluble in water, and 
 similar in its composition to cellulose. According to Dr. Calvert, of 
 Manchester, an action almost as destructive as that of dilute mineral acids is 
 exercised upon cotton and linen fibre by several organic acids. This statement 
 led to some enquiries on the subject by M. A. Dollfus. The acids used were 
 oxalic, tartaric, and citric, these being most often employed in printing calico, 
 muslin, and other tissues. Pieces of very fine linen tissue and of muslin, after 
 bein<* thoroughly washed in distilled water, were steeped in aqueous solutions, 
 each containing 2 per cent of vegetable acids. They were then dried in air, 
 and exposed for one hour to respective temperatures of 176 , 212 , and 258 - 8°, 
 with the results shown in Table I., p. 19. 
 
 Oxalic acid exerts a destructive influence equal to that of mineral acids. 
 Among the pieces of tissue soaked in the acids aboved named, that which was 
 steeped in oxalic acid assumed the darkest shade of brown, proving that the 
 alteration in in direct proportion tc the colouration.* Dr. Calvert's experiments 
 made with solutions containing 4 per cent of water led to the results shown 
 in Table II., p. 19. According to this author aqueous solutions of these 
 acids containing 2 or 4 per cent act better when gum or gelatine is added to 
 them in the proportion used for thickening, and the tissues exposed to the 
 same temperature. The researches of M. Dollfus tend to prove the reverse, 
 for in his experiments solutions containing 2 and 4 per cent of the acids and 
 thickened with gum affected the tissue less than when no thickening was 
 used. The action of acetic acid, even the glacial, is very slight ; if a 
 tissue be steeped in it and then dried scarcely any alteration takes place. 
 
 * It is not improbable that part of the effect of the organic acids on cellulose may have 
 been due to an admixture of traces of some mineral acid, such as sulphuric or nitric acid. 
 
CELLULOSE. 
 
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 20 DYEING AND CALICO PRINTING. 
 
 Dr. Calvert proposes to utilise the different attion exercised by mineral acids 
 upon vegetable and animal fibre as a meanB of distinguishing them in mixed 
 tissues. When a piece of woven fabric, whose warp consists of cotton 
 thread, is soaked in dilute sulphuric or hydrochloric acid and dried at 2i2°, 
 the cotton thread is readily torn asunder, whilst the woollen thread remains 
 as strong as before. This plan is applied on a large scale to worn-out fabric 
 composed partially of wool, in order to recover the wool for use again in making 
 similar fabrics or for working up into cloth. What is now known as vegetable 
 parchment is made by soaking unsized paper (cellulose in the state of felt) for 
 half a minute in concentrated sulphuric acid, and then washing it in large 
 quantities of water, to the last of which ammonia has been added, when it 
 assumes the aspect and consistence of an animal membrane. Gun-cotton con- 
 sists of cellulose which has been acted upon by very strong nitric acid or by a 
 mixture of concentrated sulphuric and nitric acids. An aqueous liquid con- 
 taining ammoniacal solution of oxide of copper in sufficient quantity will 
 dissolve cellulose, which can, however, be precipitated from it by acids without 
 having suffered any chemical change, but with the entire loss of its organic 
 structure. Gun-cotton is not soluble in this reagent, which is called from the 
 name of its discoverer, Schweitzer's. Cellulose is blackened by fluoride of 
 boron, but gun-cotton is not. Caustic and carbonated alkalies do not act upon 
 cellulose even when warm, either in dilute or moderately strong solutions. 
 According to M. Schwartz, cotton tissues placed in milk of lime are per- 
 ceptibly weakened and deprived of their tensile strength unless they are kept 
 from all contact with air. When submitted to the action of concentrated 
 solutions of caustic alkalies either at the ordinary or a higher temperature, 
 cellulose swells and becomes disintegrated. The action is, however, slow, 
 especially with cellulose in a very compact and condensed form and free 
 from incrustating matter, as, for instance, the so-called vegetable ivory 
 (Pliytclcphas macrocarpa), an intrinsically pure and highly condensed form of 
 cellulose. When a mixture of cellulose and a highly concentrated solution 
 of caustic potash are heated in a pure silver basin to about 662 , a simultaneous 
 formation occurs of formiate, acetate, and carbonate, of potassa, with evolution 
 of hydrogen gas and vapours of methylic alcohol (wood spirit). Chlorine gas 
 and hypochlorous acid (hypochlorites, bleaching-powder) in a state of aqueous 
 solution are not injurious to cellulose nor weakening to fibre, especially if 
 not used at too high a temperature. In a more concentrated state and at 
 a higher temperature chlorine and the above-mentioned preparations of it 
 are highly deleterious, dissolving, burning, or destroying the cellulose 
 entirely, and breaking up the fibre. According to Dr. Gladstone, cellulose will 
 combine with caustic potassa, but water decomposes the combination, which 
 is stable enough in absolute alcohol. 
 
 Having thus examined and pointed out the properties of cellulose, atten- 
 tion will next be turned to those kinds of vegetable fibre which are employed on 
 a large scale, beginning with that one which is the most important of all from 
 a manufacturing and commercial point of view, namely, cotton. 
 
(21) 
 
 CHAPTER III. 
 
 COTTON. 
 
 '"PHIS fibre is the product of a dicotyledonous plant or shrub belonging to 
 the natural order of the Malvacece, and called Gossyf>ium arboreum ; the 
 word cotton (French, coton) is of Arabian origin. Cotton is found principally 
 in India, and was known and used there, as well as in Persia, Egypt, and Asia 
 Minor, many centuries before the discovery of America, when it was found to 
 be tolerably well known in that country also. Pliny mentions cotton as an 
 Egyptian product, calling it xy Ion or gossypion. According to M. Ampere, jun., 
 the microscopical examination of the wrappings of mummies show that woven 
 cotton tissue was first used for that purpose about 80 a.d. In the year 1834,* 
 James Thomson, F.R.S., instituted some interesting researches on this subject. 
 He says : — 
 
 " My attention was attracted to the subject of Egyptian manufactures by the 
 late Mr. Belzoni in the year 1822, during the exhibition of a model of the 
 ancient tomb discovered by that enterprising traveller in Egypt. He had the 
 goodness to present to me various specimens of cloth, chiefly from the 
 mummies in his possession, one of which he had entirely denuded. 
 
 " On my remarking that these fabrics scarcely deserved the appellation of 
 ' fine linen,' which from all antiquity had been bestowed on the linen of Egypt, 
 and that the observations of Dr. Hadley, in the " Philosophical Transactions " 
 for the year 1764, had thrown some doubt on the supposed fineness of this 
 linen, he informed me that, during his researches in Egypt in those tombs and 
 mummy-pits which he had explored, he had met with cloth of every degree of 
 fineness, from the coarsest sacking to the finest and most transparent muslin, 
 a fact which I subsequently found in a great degree confirmed by the acquisi- 
 tion of some interesting specimens of mummy-cloth sent to this country by the 
 then Consul General of Egypt, the late Mr. Salt. The subject appearing to 
 me sufficiently interesting to deserve investigation, and having collected a 
 variety of specimens of cloth, my first care was to ascertain of what material 
 they were made. This question had already engaged the attention of various 
 enquirers and given birth to learned dissertations. 
 
 " Rouelle, in the " Memoirs of the French Academy of Sciences" for the 
 year 1750 ; Larcher, the translator of " Herodotus," in the notes to that cele- 
 brated work; and the learned John Reinhold Foster, who wrote a trad " De 
 Bysso Antiquorum," had all endeavoured to prove from their own examination 
 
 * The London and Edinburgh Philosophical Magazine, vol. v., p. 355. 
 
" 
 
 
 
 3W"! 
 
 WHS 
 
 22 DYEING AND CALICO PRINTING. 
 
 that the mummy-cloth of Egypt was cotton ; and this opinion, on their 
 authority, was adopted by the learned of Europe. It is singular that neither 
 in the memoir of Rouelle, nor in the notes of Larcher, nor in the dissertation 
 of Dr. Foster, in which this opinion is expressed, are any grounds assigned for, 
 or any proofs given of, this opinion. The amount of their assertion is, that 
 having examined the bandages of various mummies which are designated by 
 them, and some of which I have myself since carefully examined, they found all 
 those which were free from resinous matter to be cotton. I am forced to con- 
 fess that, with all the attention I could bestow upon them, and with the 
 assistance of various intelligent manufacturers, I was unable to arrive at such 
 a conclusion. Some were of opinion that the cloth was cotton ; others that it 
 was linen ; and some, again, that there were in the collection specimens of 
 both — a proof that our means of judging were unworthy of confidence. 
 
 " The great difference in the specific gravities, as well as in the conducting 
 power of linen and cotton, is sufficient to enable us, by careful experiments, to 
 discriminate accurately between them ; and there are few individuals who have 
 been accustomed to the use of both cotton and linen who cannot readily 
 distinguish, by that delicate sense of touch diffused over the whole body, 
 between the two fabrics ; but such tests require much larger portions of the 
 material than I had at my disposal, many of the specimens submitted to my 
 examination not being larger than a shilling. I found the difference of smell 
 in the burnt fibres, and the degree of polish which each kind of cloth took on 
 being rubbed with a glass stopper, as well as other empirical modes suggested 
 to me, liable to great uncertainty, and I sought in vain for any chemical test. 
 It occurred to me that the supposed unfitness of cotton lint, compared with 
 linen, for dressing wounds had been accounted for by the different form of 
 their fibres, the one being sharp and angular and the other round and smooth ; 
 and, in fact, I found, in the 12th volume of the " Philosophical Transactions," 
 for the year 1678, this structure ascribed to them by that early microscopic 
 observer, M. Leuwenhoek. It seemed to me, therefore, that the most simple 
 mode of distinguishing between cotton and linen would be to subject the fibres 
 to examination under a powerful microscope. Not being possessed of such an 
 instrument, nor accustomed to its management, my friend Mr. Children under- 
 took, through Sir Everard Home, to solicit the assistance of M. Bauer, whose 
 labours are well known to the scientific world, and whose microscopic drawings 
 have for a series of years enriched the " Transactions of the Royal Society." I 
 transmitted to him various fibres of cotton and linen, both manufactured and 
 in their raw state, as well as fibres of unravelled mummy-cloth, and in a few 
 days I received from him a letter in which he pronounced every specimen of 
 mummy-cloth subjected to his examination to be linen. This letter was 
 accompanied by a beautiful drawing, exhibiting the fibres of both raw and 
 unravelled cotton as flattened cylinders, twisted like a corkscrew, whilst the 
 fibres of linen and various mummy-cloths were straight and cylindrical. 
 
 " Repeated observations having established beyond all doubt the power of 
 the microscope accurately to distinguish between the fibres of cotton and linen, 
 I obtained, through the kindness of various individuals connected with the 
 British Museum, the Royal College of Surgeons, the Hunterian Museum of 
 Glasgow, as well as other public institutions both at home and abroad, a great 
 variety of cloths of human mummies, and of animals and birds, which, being 
 subjected to the microscope of M. Bauer, proved without exception to be linen ; 
 
MUMMY-CLOTH. 
 
 23 
 
 nor has he, amongst the numerous specimens we have both collected during 
 many years, been able to detect a single fibre of cotton, a fact since recently 
 confirmed by others, and proving incontestably that the mummy-cloth of Egypt 
 was linen. 
 
 " The filaments of cotton, when viewed through a powerful instrument, such 
 as the improved achromatic microscope of Ploessl, of Vienna, which, for mag- 
 nifying power and clearness of vision, M. Bauer has found superior to every 
 other he has had an opportunity of using, appear to be transparent glassy tubes 
 flattened and twisted round their own axis. A section of the filament resembles 
 in some degree a figure of 8, the tube, originally cylindrical, having collapsed 
 most in the middle, forming semi-tubes on each side, which give to the fibre, 
 when viewed in certain lights, the appearance of a flat ribbon with a hem or 
 border at each edge. The uniform transparency of the filament is impaired by 
 small irregular figures, in all probability wrinkles or creases, arising from the 
 desiccation of the tube. The twisted and corkscrew form of the filament of 
 cotton distinguishes it from all other vegetable fibres, and is characteristic of 
 the fully ripe and mature pod, M. Bauer having ascertained that the fibres of 
 the unripe seed are simple untwisted cylindrical tubes, which never twist after- 
 wards if separated from the plant; but when the seeds ripen, even before the 
 capsule bursts, the cylindrical tubes collapse in the middle and assume the form 
 already described. 
 
 " This form and character the fibres retain ever after, and in that respect 
 undergo no change through the operation of spinning, weaving, bleaching, 
 printing, and dyeing, nor in all the subsequent domestic operations of washing, 
 &c, till the stuff is worn to rags ; and then even the violent process of reducing 
 those rags to pulp for the purpose of making paper effects no change in the 
 structure of these fibres. ' With Ploessl's microscope,' says M. Bauer, ' I can 
 ascertain whether cotton rags have been mixed with linen in any manufactured 
 paper whatever.' 
 
 " The elementary fibres of flax (Linum usitatissimum) are also transparent 
 tubes, cylindrical, and articulated or jointed like a cane. This latter structure 
 is only observable by the aid of an excellent instrument. 
 
 " Of the productions of the loom amongst the nations of antiquity, with the 
 exception of those which form the subject of this paper, we know only what is 
 to be gathered from the few scattered notices in ancient writers. Even the 
 great work of Pliny, the encyclopoedia of that day, and, with all its defects, an 
 invaluable collection of fads, affords but scanty information. Of the manu- 
 factures of the Egyptians and of their domestic arts our knowledge is more 
 ample, but we are more indebted to their monuments than to their historians ; 
 and the paintings which adorn their tombs, and which are fresh at the present 
 day as from the hand of the artist, have revealed to us more than all the writers 
 of antiquity. 
 
 " Of the products of the Egyptian loom, however, we know scarcely more than 
 the mummy-pits have disclosed to us ; and it would be as unreasonable to look 
 through modern sepulchres for specimens and proofs of the state of manu- 
 facturing art amongst ourselves as to deduce an opinion of the skill of the 
 Egyptians from those fragments of cloth which envelope their dead, and which 
 have come down, almost unchanged, to our own time. The curious or costly 
 fabrics which adorned the living, and were the pride of the industry and skill 
 of Thebes, have perished ages ago. There are, however, amongst these 
 
DYEING AND CALICO PRINTING. 
 
 remains some which are not unworthy of notice, which carry us back into the 
 workshops of former times, and exhibit to us the actual labours of the weavers 
 and dyers of Egypt more than two thousand years ago. 
 
 "The great mass of mummy-cloth employed in bandages and coverings, 
 whether of birds, animals, or of the human species, is of coarse texture, 
 especially that more immediately in contact with the body, and which is 
 generally impregnated with resinous or bituminous matter. The upper 
 bandages nearer the surface are finer. Sometimes the whole is enveloped in a 
 covering coarse and thick, and very like the sacking of the present day; some- 
 times in cloth coarse and open like that used in our cheese-presses, for which 
 it might easily be mistaken. In the College of Surgeons are various specimens 
 of these cloths, some of which are very curious. 
 
 " The beauty of the texture and peculiarity in the structure of a mummy- 
 cloth given to me by M. Belzoni was very striking. It was free from gum or 
 resin, or impregnation of any kind, and had evidently been originally white. 
 It was close and firm, yet very elastic. The yarn of both warp and woof was 
 remarkably even and well spun. The thread of the warp was double, consisting 
 of two finer threads twisted together. The woof was single. The warp con- 
 tained ninety threads in an inch ; the woof, or weft, only forty-four. The 
 fineness of these materials, estimated after the manner of cotton yarn, was 
 about thirty hanks in the pound. The subsequent examination of a great 
 variety of mummy-cloths showed that the disparity between the warp and woof 
 belonged to the system of manufacture, and that the warp generally had twice 
 or thrice, and not seldom four times, the number of threads in an inch that 
 the woof had. Thus, a cloth containing 80 threads of warp in the inch, of a 
 fineness of about 24 hanks in the pound, had 40 threads in the woof; another, 
 with 120 threads of warp of 30 hanks, had 40 ; and a third specimen only 30 
 threads in the woof. These have each, respectively, double, treble, and 
 quadruple the number of threads in the warp that they have in the woof. 
 This structure, so different from modern cloth, which has the proportions 
 nearly equal, originated probably in the difficulty and tediousness of getting in 
 the woof when the shuttle was thrown by hand, which is the practice in India 
 at the present day, and which there are weavers still living old enough to 
 remember the universal practice in this country. 
 
 " I have alluded to some specimens of mummy-cloth sent to this country by 
 the late Mr. Salt. I am unacquainted with their history or origin further than 
 that they were brought from Thebes, and were contained in the outer packing- 
 case of a mummy now in the British Museum. They were evidently the spoils 
 of some other mummy, but when and where opened I have in vain endeavoured 
 to learn. There were various fragments of different degrees of fineness, some 
 fringed at the ends and some striped at the edges. They merit a more par- 
 ticular description. 
 
 "My first impression on seeing these cloths was that the finest kinds were 
 muslin, and of Indian manufacture, since we learn from the " Periplus of the 
 Erythrean Sea," ascribed to Arrian, but more probably the work of some Greek 
 merchant himself engaged in the trade, that muslins from the Ganges were an 
 article of export from India to the Arabian Gulf; but this suspicion of their 
 being cotton was soon removed by the microscope of M. Bauer, which showed 
 that they were all, without exception, linen. 
 
 M Some were thin and transparent and of very delicate texture. The finest 
 
MUMMY-CLOTH. 
 
 25 
 
 appeared to be made of yarns of near 100 hanks in the pound with 140 threads 
 in the inch in the warp, and about 64 in the woof. A specimen of muslin in 
 the Museum of the East India House, the finest production of the Dacca loom, 
 has only 100 threads in an inch in the warp, and 84 in the woof; but the 
 surprising fineness of the yarns, which, though spun by hand, is less than 
 250 hanks in the pound, gives to this fabric its unrivalled tenuity and light- 
 ness. Some of the cloths were fringed at the ends, and one, a sort of scarf 
 about 4 feet long and 20 inches wide, was fringed at both ends. Three or four 
 threads twisted together with the fingers to form a strong one, and two of 
 these a^ain twisted together and knotted at the middle and at the end to 
 prevent unravelling, formed the fringe, precisely like the silk shawls of the 
 present day. 
 
 " The selvedges of the Egyptian cloths generally are formed with the greatest 
 care, and are well calculated by their strength to protect the cloth from accident. 
 Fillets of strong cloth or tape also secure the ends of the pieces from injury, 
 showing a knowledge of all the little resources of modern manufacture. 
 Several of the specimens, both of fine and coarse cloth, were bordered with 
 blue stripes of various patterns, and in some alternating with narrow lines of 
 another colour. The width of the patterns varied from half an inch to an inch 
 and a quarter. In the latter were seven blue stripes, the broadest about half 
 an inch wide nearest the selvedge, followed by five very narrow ones, and 
 terminated by one an eighth of an inch broad. Had. this pattern, instead of 
 being confined to the edge of the cloth, been repeated across its whole breadth, 
 it would have formed a modern gingham, which we can scarcely doubt was one 
 of the articles of Egyptian industry. A small pattern about half an inch broad 
 formed the edging of one of the finest of these cloths, and was composed of a 
 stripe of blue followed by three narrow lines of the same colour, alternating 
 with three lines of fawn-colour, forming a simple and elegant border. These 
 stripes were produced in the loom by coloured threads previously dyed in the 
 yarn. The nature of the fawn-colour I was unable to determine. It was too 
 much degraded by age, and the quantity too small, to enable me to arrive at 
 any satisfactory conclusion. Though I had no doubt the colouring matter 
 of the blue stripes was indigo, I subjected the cloth to the following examina- 
 tion : — Boiled in water for some time, the colour did not yield in the least, 
 nor was it at all affected by soap nor by strong alkalies. Sulphuric acid, diluted 
 only so far as not to destroy the cloth, had no action on the colour. Chloride 
 of lime gradually reduced, and at last destroyed it. Strong nitric acid dropped 
 upon the blue turned it orange, and in the same instant destroyed it. These 
 tests prove the colouring matter of these stripes to be indigo. 
 
 " This dye was unknown to Herodotus, for he makes no mention of it. It was 
 known to Pliny, who, though ignorant of its true nature and the history of its 
 production, has correctly described the most characteristic of its properties, the 
 emission of a beautiful purple vapour when exposed to heat. Had his com- 
 mentators been acquainted with the sublimation of indigo it would have saved 
 many learned doubts. We learn from the " Periplus " that it was an article 
 of export from Barbarike on the Indus to Egypt, where its employment by the 
 manufacturers of that country, probably from a remote period, is clearly 
 established by the specimens here described. 
 
 "Amongst the various cloths for which I am indebted to the curators of the 
 Hunterian Museum at Glasgow, is one of a pale brick or red colour. My 
 
m 
 
 
 26 
 
 DYEING AND CALICO PRINTING. 
 
 attention was lately recalled to this specimen by observing a similar colour 
 in the outer coverings of two fine mummies presented to the University of 
 London by Mr. Morrison, one of which has been recently unrolled. Having 
 obtained specimens of both, I subjected them, with that from Glasgow, to the 
 following experiments :— Treated with cold water the colour was not affected. 
 Boiling distilled water in a few minutes nearly removed the whole. Diluted 
 sulphuric or muriatic acid had no action on it ; but a feeble alkali, whether 
 carbonated or caustic, destroyed the colour immediately. Examined with a 
 lens, the specimens from Glasgow exhibited small distinct grains or concretions, 
 of a red colour, disseminated through the fibres of the cloth. Notwithstanding 
 the fugitive nature of the colouring matter of safflower, the Carthamus 
 tinctovius of botanists, I am strongly disposed to consider the three specimens 
 here examined as having been dyed with that plant, the small granular 
 particles of a red colour observed in the Glasgow specimen are sometimes 
 found in cloth dyed with Carthamus. Theie is also in the covering of the 
 mummy of the London University, which is unstripped, a rosy hue peculiar to 
 this dye. The resistance of the colour to acids, and its instant yielding to 
 the weakest alkalies, is characteristic of safflower. Lastly, Carthamus has 
 long been an article of cultivation in Egypt, and the first processes employed 
 by the European dyers were derived, with the dye itself, from that country, 
 where, in all probability, it has been cultivated and used for ages, and is to 
 this day an article of considerable export. 
 
 " In the Glasgow mummy there was, moreover, a narrow slip of cloth about 
 four inches broad, extending from the crown of the head to the feet, of a 
 yellowish colour, of which portions were still fresh. On examination, no 
 mordant appeared to have been used to fix this dye, and washing in cold water 
 greatly impaired it. Comparative experiments made on this colour, and on 
 that afforded by Carthamus to simple water before the pink dye is extracted, 
 left little doubt of their being identical. They were slightly and similarly 
 affected by solutions of alumina and of iron, and appeared to have very feeble 
 affinities for either vegetable fibre or any of the earthy or metallic bases. 
 
 " Though the age of mummies from which these specimens were derived 
 has not been ascertained, yet we may fairly presume that it goes back to a 
 period so far remote as to make the preservation so long, of delicate and 
 fugacious colouring matter like Carthamus, or even the more permanent one 
 of indigo, very surprising, and proves that substances which readily yield to 
 the combined and destructive agency of heat or light and moisture are almost 
 unalterable when secured from the action of the latter. Portions of ihe blue 
 cloth which had resisted in the dark and dry sepulchres of Thebes for ages lost, 
 by a few days' exposure on the grass, nearly all their colour. 
 
 " Mummy-cloth not stained or discoloured by resin or bitumen is generally 
 of a pale brown or fawn colour, which has been supposed to arise from some 
 astringent preparation employed by the Egyptians for its preservation. All 
 this cloth imparts to water a brown colour, in which I have sought in vain for 
 any trace of tannin. In none of the specimens I have examined did either 
 gelatine or albumen, or solutions of iron, afford any precipitate ; but the sub- 
 acetate of lead produced a cloud, indicating the presence of extractive matter. 
 I am inclined to think that, if astringent matter has been found, it is in those 
 bandages which have received a preparation of gum or resin, and which are 
 distinguished from the others h* their stiffness. These I have not examined. 
 
COTTON. 27 
 
 All these cloths, whether fine or coarse, are more or less rotten. Of the 
 numerous specimens which have fallen under my notice, the outer covering of 
 the fine mummy in the London University has suffered least ; it is compara- 
 tively sound. Whether this be an argument against its high antiquity I know 
 not, but the cloth is evidently ancient Egyptian ; nor is it, I believe, pretended 
 that in those factitious mummies manufactured by the Arabs, of which several 
 were found by Blumenbach in the British Museum, the bandages and envelopes 
 are not genuine. Of the ancient cloth, there is such an accumulation in the 
 mummy-pits and sepulchres of Egypt as to have become a subject of specula- 
 tion in Europe for the purpose of making paper. The inquiries, therefore, 
 which form the subject of this communication are not affected by any question 
 of the integrity of those mummies from whence the specimens were derived, of 
 which, however, no doubt is entertained. 
 
 " The period during which the custom of embalming prevailed in Egypt 
 embraces a long succession of ages. From the first of the Pharaohs to the last 
 of the Ptolemies, with whom this ancient right is supposed to have become 
 almost extinct, chronologists reckon more than twenty centuries during which 
 the art was practised which has handed down to us these scanty remains of 
 Egyptian industry, the only vestiges of the labours of the ancient loom now 
 in existence. They prove the arts of spinning and weaving flax to have 
 attained a high degree of perfection, many of the specimens of mummy-cloth 
 here described being of a quality to excite admiration even at the present day, 
 and the finest of these fabrics approaching in excellence our delicate muslins. 
 The coloured borders establish the fact of indigo having been known and used 
 as a dye in Egypt from a remote era. 
 
 " During this long period industry and the arts of life connected with 
 civilisation must have made considerable progress, which we shall, however, 
 remain unable satisfactorily to trace till more accurate knowledge of the 
 ancient language and characters of the Egyptians shall have interpreted the 
 dates and fixed the chronology of their monuments and paintings. In the 
 tomb of Beni Hassan is a representation of a loom (figured in Count Minutoli's 
 travels) of such primeval simplicity as to resemble the first rude efforts of savage 
 art to form a web such as Don Ulloa in his voyages has described as used by 
 the native Indians of South America. Between this loom and that in which 
 the corslet of Amasis was woven, mentioned by Herodotus, and more particularly 
 described by Pliny, the distance is immense. 
 
 " It is not improbable that future researches directed to this object may 
 discover, in the ancient sepulchres and mummy-pits, fragments of cloth, now 
 trodden under foot and unheeded by the traveller, which would throw much 
 light on the interesting subject of ancient manufactures. 
 
 " The question debated amongst the learned of the nature of the Byssus of 
 the ancients, I may in conclusion be permitted to observe, appears to me to be 
 finally settled by the present communication. Herodotus states that the 
 Egyptians wrapped their dead in cloth of the Byssus. It has been shown 
 that, without exception, every specimen of mummy-cloth yet examined has 
 proved to be linen. We owe, therefore, the satisfactory establishment of the 
 fact, that the Byssus of the ancients was flax, to the microscope of M. Bauer." 
 The cotton shrub grows only in the warmer (tropical and sub-tropical) 
 portions of the globe. The most important varieties are the Gossypium 
 arborcum and Gossypium hcrbaccum. The Gossypium hcrbaccum is generally 
 
28 
 
 DYEING AND CALICO PRINTING. 
 
 cultivated at Malta, in Sicily, in Syria, and other portions of the Levant, and 
 in the islands of the Greek Archipelago. At Malta and Sicily this plant is 
 herbaceous and annual, but in warmer climates it becomes a perennial shrub 
 growing to the height of about 7 or 9 feet. The Indian cotton shrub is a 
 sub-species of the foregoing, but is perennial. The Gossypium arbor eum is a 
 tree which attains a height of about 15 or 18 feet. It is cultivated in India, 
 Arabia, China, the Canary Islands, and especially in the United States of 
 America. 
 
 The fruit of the cotton tree consists of a capsule containing from three to five 
 valves, and as many divisions holding a number of seeds. These seeds are 
 each surrounded by a flock of cotton, which becomes swollen when the 
 seed reaches maturity, and the valves consequently open. The cotton 
 gathering lakes place in August, September, or October, according to the 
 climate. The shells of the fruit are left on the tree, but the cotton and the 
 seeds are pulled off, and after being dried in the sun are separated from each 
 other by a machine known either as the roller gin, the Macarthy gin, or the 
 saw gin. 
 
 The quality of the cotton is judged by the length of its fibres, long ones 
 being about 1 inch (from 2 to 4 centims.) in length, and short ones about 
 J an inch (from 1*5 to 2 centims.) The United States produce the best kinds 
 of both these varieties. The cotton grown in Algeria and Brazil is all of the 
 long kind. India and the Levant produce both varieties. 
 
 Cotton filaments or fibres when fully ripe but not dried exhibit under the 
 microscope a membranous hollow tube of cylindrical shape, and closed at both 
 ends. When dry this cylinder becomes flattened and twisted, and assumes a 
 ribbon-like shape rather thicker at the edges than in the middle. Its largest 
 diameter is about 0*03937 ol ~ a millimetre, but it tapers off cylindrically at both 
 ends; on examination with a lens magnifying 400 times no opening whatever is 
 seen inside the walls of the cylindrical cell, but it is nevertheless permeable by 
 liquids. According to the late Mr. Walter Crum, the examination of sections 
 of cotton fibres taken perpendicularly to their length proves that they are nearly 
 solid : some of these sections are of a cylindrical shape, but the greater part 
 are irregularly oblong or oval, bearing some likeness to the fibres of flax and 
 hemp. According to M. Alcan, the author of a French treatise on cotton 
 spinning, the peculiar action of cotton upon concentrated aqueous solutions of 
 caustic soda and potash was first discovered and pointed out by the late 
 M. Persoz. Mr. John Mercer, however, turned this discovery to practical use, 
 and patented a process known as Mercerising. By this process the woven 
 tissue is immersed for a few minutes only in a solution of caustic soda 
 (sp. gr. i , 25o), and immediately afterwards well washed in plenty of cold 
 water, after which it is passed through an acid bath. The result is con- 
 traction of fibre, the threads becoming rounder, firmer, and closer together, 
 the loss in length and breadth to the material being about i-i5th each way. 
 Cotton tissue thus treated has an especial affinity for some colours, especially 
 for indigo-blue. The process has, however, been abandoned on account 
 mainly of the expense of the soda, which was not justified by the results 
 obtained. M. Daniel Kcechlin-Schouch, of Mulhouse, was the first to call 
 the attention of dyers and printers to the occasional occurrence in cotton 
 fabrics of fibres which resist the dye and remain white ; this was attributed 
 by him to non-maturity of the fibre, a surmise which was confirmed by the 
 
COTTON. 
 
 29 
 
 experiments of Mr. Walter Crum. These so-called dead fibres when 
 examined with a microscope were found to be of such very thin texture as to 
 be almost invisible except at the edges ; they are nearly twice as wide as 
 ordinary ripe cotton, and contain a larger number of longitudinal and transverse 
 folds. This dead cotton is not equally conspicuous with all dyes ; it is very 
 apparent with indigo and madder-pink, but not so with safflower and deep 
 madder-red. 
 
 For the benefit of those to whom the " Memoirs of the Literary and 
 Philosophical Society of Manchester " may not be conveniently accessible, we 
 abridge from the fourth volume of the third series some of the interesting and 
 highly valuable researches of Dr. Schunck, F.R.S., "On some Constituents of 
 the Cotton Fibre." 
 
 Dr. Schunck's endeavour was to throw a little more light on the nature of 
 the substances which are contained in or attached to the framework of 
 cellulose of which cotton fibre mainly consists, and which are, together with 
 the latter, produced by the plant, without taking into consideration the foreign 
 and extraneous matters introduced during the process of manufacture. It is 
 well known that these substances are almost insoluble in water, but soluble 
 in hot alkaline lye. Indeed the principal operation in the bleaching of cotton 
 goods consists in subjecting them for some time to the action of boiling 
 solutions of soda or some other alkali — chlorine or its compounds being only 
 used to impart to them the highest degree of whiteness. Dr. Schunck con- 
 fined himself in this investigation to those natural constituents of cotton 
 fibre which are insoluble in water, but soluble in alkaline lye, and which are 
 afterwards precipitated from the alkaline solution by acid. He employed 
 cotton-yarn made from definite unmixed kinds of cotton. Apart from 
 financial considerations, yarn presents certain advantages as compared with 
 raw cotton. It is much freer from mechanical impurities, which are to a great 
 extent removed during, or rather previously to, the operations of spinning; 
 while, on the other hand, in a well-ordered manufactory, little or nothing 
 of a foreign nature is added to the cotton to render it impure. It can also be 
 treated without any trouble, and in large quantities, in the ordinary vessels 
 used by bleachers, without rendering it necessary to set up special apparatus 
 for the purpose. 
 
 In the first experiment, 450 lbs. of No. 20 yarn, carefully spun from East 
 Indian cotton, of the variety called " Dhollerah," was treated, in an ordinary 
 bleacher's kier heated by steam, with boiling water containing 13.5 lbs. of soda- 
 ash for seven and a half hours. The resulting dark brown liquor, after the 
 yarn had been taken out, drained, and slightly washed, was removed into 
 another vessel and mixed with an excess of sulphuric acid, which produced a 
 copious, light brown, flocculent precipitate, while the liquid became nearly 
 colourless. This precipitate was allowed to settle ; the liquid was poured off, 
 and, after being washed with cold water to remove the sulphate of soda and 
 excess of acid, the precipitate was put on strainers of calico and allowed to 
 drain — an operation which, in consequence of its gelatinous nature, occupied 
 some time. A thick pulp was thus obtained, which was found to weigh 60 lbs. 
 Of this 3 lbs. was taken and dried completely, at first in a stove and then in a 
 water-bath, when it left 531 grs. of a brown, brittle, horn-like substance, 
 translucent at the edges. The whole of the precipitate, if dried, would there- 
 fore have weighed 10,620 grs., which is equal to 0-337 per cent of the weight 
 

 30 
 
 DYEING AND CALICO PRINTING. 
 
 of the cotton ; that is to say, iooo lbs. of cotton-yarn would have yielded 
 nearly 3% lbs. of matter insoluble in water, but soluble in alkali. This result 
 is, of course, only approximative. 
 
 In a second experiment 2400 lbs. of yarn, made from the same kind of 
 cotton, but of rather inferior quality, was treated in the same way ; but the 
 quantity of precipitate obtained was not determined. 
 
 The third experiment was made with 500 lbs. No. 20 yarn, spun from 
 American cotton of the kind called in commerce " Middling Orleans." It was 
 treated in the same manner as the other two lots, and yielded a precipitate 
 of exactly the same appearance as that from East Indian cotton, and 
 amounting, when dry, to 0*48 per cent of the weight of the yarn employed. 
 
 The precipitate in all three cases consisted for the most part of organic 
 matter. In addition to the matter extracted from the cotton by the alkali, it 
 contained a small quantity of cotton filaments, which had been detached 
 from the yarn during the process of boiling. When incinerated, it left from 
 23 to 69 per cent of a light yellow non-alkaline ash. This ash consisted 
 chiefly of oxide of iron, alumina, and silicate of alumina, the remainder being 
 sulphate of lime and sulphate of soda. 
 
 The three lots of precipitate obtained were treated separately; but as the 
 products which they yielded were essentially the same, the same process of 
 treatment was applied to all. This process was as follows: — 
 
 The precipitate was in the first instance treated, while still moist, with 
 boiling alcohol, and the boiling liquid was filtered through a large tin funnel, 
 surrounded by hot water. The residue on the filter was treated again with 
 boiling alcohol, and the process was repeated until nothing more was dissolved. 
 More than half of the precipitate remained undissolved. The undissolved 
 residue was much paler than the original precipitate, the colouring material of 
 which had, for the most part, passed into solution. The alcoholic liquid, 
 which was of a dark brown colour, deposited, on cooling, a quantity of dirty 
 white flocks, which were filtered off, washed with alcohol, and then re-dissolved 
 in boiling alcohol. On adding to this solution a little acetate of lead, a dark 
 brown precipitate was produced, consisting of a compound of colouring matter 
 with lead ; and the liquid, after being filtered as before through a hot water 
 funnel, and allowed to cool, deposited a quantity of nearly white flocks. 
 These were filtered off, washed with alcohol to remove the excess of lead-salt, 
 and then treated with boiling dilute caustic soda-lye, in which they melted 
 like wax or fat, without dissolving. The mass, after cooling, was filtered off, 
 washed with water, and then dissolved again in boiling alcohol, to which a 
 little animal charcoal was added. The solution, which was quite colourless, 
 deposited, after filtration and cooling, a quantity of crystalline scales, of a 
 beautiful pearly lustre, and generally in such abundance as to convert the 
 liquid into a thick jelly. This deposit, which was at first very bulky, on being 
 filtered off and dried, shrank considerably, and yielded at last a white or 
 faintly yellow wax-like cake, consisting of a body termed by Dr. Schunck 
 Cotton Wax. 
 
 The alcoholic liquid from which this substance was deposited was of a dark 
 brown colour. It contained two bodies, which, for want of a better term, may 
 be called colouring matters, and also a small quantity of a crystalline fatty 
 acid having the properties and composition of margaric acid. The two 
 colouring matters resemble one another in most of their properties, but may 
 
COTTON. 
 
 3i 
 
 be distinguished by their different degrees of solubility in alcohol — one being 
 easily soluble in cold alcohol, the other soluble in boiling, but very little 
 soluble in cold alcohol. As these substances possess very few characteristic 
 properties, and it is doubtful whether they are peculiar to cotton or not, the one 
 which is most easily soluble in alcohol is called simply Colouring matter A, the 
 other Colouring matter B. These bodies were separated from one another and 
 from the fatty acid in the following manner: — The liquid having been 
 evaporated, left a brown, semi-solid, resinous mass, which was treated with a 
 small quantity of warm or boiling alcohol. This dissolved only a part of the 
 mass, the remainder being left undissolved as a brown powder, consisting for 
 the most part of the colouring matter B. The liquid having been filtered, 
 the powder was treated with a large quantity of boiling alcohol, in which 
 it usually dissolved almost entirely. A small quantity, however, of a brown 
 flocculent substance was generally left undissolved ; and this substance, 
 which consisted of impure pectic acid, having been filtered off while the liquid 
 was hot, the latter, on cooling, deposited the greatest part of the colouring 
 matter as a brown powder, which only required to be filtered off, washed with 
 alcohol, and dried. The dark brown alcoholic liquid, containing the more 
 soluble colouring matter A, as well as the fatty acid and a portion of the 
 colouring matter B, was now mixed with ammonia and chloride of barium, 
 which gave an abundant greyish brown precipitate, consisting of all the 
 organic matter previously contained in the liquid in combination with baryta. 
 This precipitate was filtered off, and then treated with boiling alcohol. The 
 latter being filtered boiling hot, afforded, on cooling, a small quantity of a 
 brownish crystalline deposit. This process was repeated as long as the 
 filtered liquid deposited anything, and until, therefore, the precipitate was 
 thoroughly deprived of everything soluble in alcohol. The crystalline matter 
 deposited from the alcoholic liquid consisted almost entirely of the baryta 
 salt of the fatty acid. After being filtered off it was treated with warm dilute 
 hydrochloric acid, by which it was decomposed, the fatty acid rising to the 
 surface as a light brown oil, which became solid on cooling. The latter, after 
 being well washed with hot water, was dissolved in warm alcohol, and the 
 solution, having been decolourised with animal charcoal and filtered, was 
 evaporated spontaneously, when it left a perfectly white mass of crystalline 
 needles, consisting of the fatty acid in a state of purity. 
 
 The baryta-precipitate, after treatment with boiling alcohol, was decom- 
 posed with warm dilute hydrochloric acid, which left undissolved a dark brown, 
 semi-fused mass. This mass, after being kneaded in hot water and thoroughly 
 freed from barium salt, was treated with boiling alcohol. The alcohol 
 generally left some brown powder undissolved, consisting of colouring matter B; 
 and an additional quantity was usually deposited from the alcohol on cooling. 
 Having been filtered off, it was purified by dissolving it in a sufficient quantity of 
 boiling alcohol, as above described. The filtered liquid left, on evaporation, 
 a dark brown resinous mass, which was reduced to a fine powder, and then 
 agitated in a flask with ether. The ether dissolved only a very small portion 
 of the mass, but it served to remove a trace of fatty acid contained in it. 
 The ether, on evaporation, left a brown fatty residue, which, after combination 
 with baryta and treatment of the compound with boiling alcohol, as just 
 described, yielded a quantity of pure fatty acid. The portion left undissolved 
 
32 
 
 DYEING AND CALICO PRINTING, 
 
 by the ether was treated with cold alcohol, which dissolved the greatest part 
 of it. The dark brown solution, after being filtered from a small quantity of 
 colouring matter B, which was usually present, was evaporated to dryness, 
 when it left a dark brown, shining, resin-like residue, consisting of the 
 colouring matter A. 
 
 The greatest part of the precipitate produced by acid in an alkaline extract 
 of cotton is insoluble in alcohol. This portion, when dry, has the appearance 
 of a brown, friable, earthy mass, among which cotton filaments, particles of 
 woody fibre, and other impurities derived from the cotton may be seen. 
 When burnt it leaves a considerable quantity of ash. Its weight, when dry, 
 amounted, in the case of East Indian cotton, to 77 per cent of that of the 
 entire precipitate, in that of American cotton to 66 per cent. Though much 
 lighter in colour than the precipitate before treatment with alcohol, it still 
 contains a quantity of colouring matter, which cannot be extracted by means 
 of boiling alcohol, not even when ammonia is added — a circumstance which 
 is due either to the presence of some colouring matter distinct from those just 
 referred to, or perhaps to the latter being intimately combined with, or firmly 
 attached to, some other constituent of the mass. Dr. Schunck supposes that 
 it contains also a small quantity of some albuminous substance, the presence 
 of some such substance being rendered probable by an examination of the 
 produces of decomposition with caustic alkali, as will be explained presently. 
 Its chief constituent, however, is a body belonging to the pedine class, 
 generally either pedic or parapedic acid, or a mixture of both. The presence 
 of some such body is indicated by the gelatinous appearance of the precipitate 
 with acid, its increasing in bulk and partially dissolving in water after the 
 precipitating acid has been removed, and its shrinking and curdling on the 
 renewed addition of acid or of salts or alcohol. Nevertheless the isolation 
 and preparation, in a state of purity, of this substance cannot be effeded 
 without considerable difficulty, in consequence of the pertinacity with which 
 the colouring matter adheres to and accompanies it. If the precipitate, after 
 exhaustion with boiling alcohol, is treated with boiling water, the latter 
 dissolves a considerable quantity of the body in question, but on evaporation 
 it leaves a dark brown residue, which, on analysis, is found to contain no in- 
 considerable amount of nitrogen, a proof of the presence of one or both of 
 the colouring matters of cotton. Dr. Schunck was unsuccessful in his 
 attempts to remove this impurity by means of animal charcoal, earths, 
 metallic oxides, or salts of any kind. He succeeded, however, in devising 
 two methods of preparing, in a state of tolerable purity, a body soluble in 
 water having the properties and composition of Fremy's parapedic acid, and 
 thus proving that cotton contains a substance belonging to the pedine series. 
 He was unable to procure pedine itself, though there can be little doubt that 
 it is pedine which exists originally in the fibre and gives rise to the formation 
 of the pedic and parapedic acids which are contained in the alkaline 
 extrad. One of the methods employed for preparing this acid, founded on 
 the insolubility of its alkaline compounds or salts in an excess of caustic 
 alkali, was as follows: — 
 
 The precipitate from the alkaline extrad of cotton, after exhaustion with 
 boiling alcohol, was, without being previously dried, dissolved in dilute caustic 
 soda-lye. The solution, after being filtered in order to separate the filaments 
 of cotton and other impurities which were present, was mixed with alcohol, 
 
COTTON. 
 
 3a 
 
 which produced an abundant light brown flocculent precipitate, consisting of 
 impure pedtate and parapedtate of soda. The liquid, which was brown, con- 
 tained a considerable quantity of colouring matter, and was filtered. The 
 precipitate, after being washed with alcohol, was again dissolved in water, and 
 to the solution there was added a quantity of strong caustic soda-lye, which 
 produced a precipitate of a much paler colour than that with alcohol, while 
 the liquid retained in solution another portion of colouring matter. The pre- 
 cipitate having been allowed to settle, the liquid was decanted, and the 
 precipitate was stirred up with a fresh quantity of caustic soda-lye, the process 
 being repeated until the supernatant liquid had become colourless. The pre- 
 cipitate was now treated with warm dilute hydrochloric acid, which took up 
 the alkali, leaving a quantity of pale brown flocks undissolved. These were 
 filtered off and washed for some time with cold water, the latter being exchanged 
 for alcohol as soon as the principal part of the acid and chloride of sodium had 
 been removed, in order to prevent a loss of parapectic acid, which is soluble in 
 pure water, though insoluble in water containing strong acids or salts. As 
 soon as the liquid ceased to give a precipitate with nitrate of silver, the mass 
 was taken from the filter, pressed between folds of blotting-paper, in order to 
 take up the alcohol, and then treated with boiling water for some time. A 
 milky liquid was thus obtained, which was set aside for some time in order to 
 allow the flocculent matter suspended in it, which prevented it from filtering 
 readily, to settle. The liquid, having been decanted from the deposit, was 
 filtered and evaporated, when it left an amorphous light brown residue, resem- 
 bling gum or gelatine, and having the properties and composition of parapectic 
 acid. The flocculent deposit consisted of pectic acid ; but it was contaminated 
 with a considerable quantity of colouring matter, from which it could, in most 
 cases, not be separated without undergoing a change. If, for instance, it was 
 dissolved again in caustic soda, and the process just described was repeated, 
 it was usually converted for the most part into a substance soluble in water — 
 that is, into parapectic acid. 
 
 The second method of preparing the acid is far less tedious, and yields a 
 product much freer from colour than the one just described. It differs, how- 
 ever, from the latter in one particular only, viz., in the use of a bleaching agent 
 instead of caustic soda as a precipitant. To the watery solution of impure 
 pedtate and parapedtate of soda, obtained in the same manner as before, there 
 was added a clear solution of chloride of lime, which produced an abundant 
 precipitate consisting mostly of pedtate and parapedtate of lime. By adding an 
 excess of the bleaching solution, the colour of the precipitate, which was at 
 first brown, became gradually lighter. As soon as it had lost all its colour, or 
 retained only a yellowish tinge, it was filtered off, washed with water, and 
 treated with dilute hydrochloric acid. The white flocks left undissolved by 
 the acid were filtered off, washed at first with water and then with alcohol, 
 and lastly treated as before with boiling water, which left the pedtic acid 
 undissolved. The filtered liquid left, on evaporation, a residue of parapectic 
 acid, having only a faint yellowish tinge like that of the purest gum. It did 
 not differ in composition from that prepared by the process first described, 
 proving that the chloride of lime produced no decomposing effect, but merely 
 served to destroy and remove the colouring matter. 
 
 The following is a short account of the properties and composition of the 
 various substances the preparation of which has been just described : — 
 
 D 
 
34 
 
 DYEING AND CALICO PRINTING. 
 
 Cotton-Wax. 
 
 There can be no doubt that this substance must be classed with the waxes, 
 bodies which are distinguished by their insolubility in water and alkaline 
 liquids, their sparing solubility in alcohol and ether, and their high melting- 
 point. Indeed it so closely resembles in many respects the better known 
 vegetable waxes, such as the cerosine prepared by Avequin from the leaves of 
 the sugar-cane, and the wax from the leaves of the Carnauba palm {Corypha 
 ccrifera), examined by Brande* and Lewyf, that its identity with one of these 
 may be suspected. It has the following properties : — 
 
 It is insoluble in water, but soluble in alcohol and ether. If a concentrated 
 solution in boiling alcohol be allowed to cool, the greatest part of the substance 
 is deposited, causing the liquid to assume the appearance of a thick white 
 jelly, like starch-paste, which, when examined under the microscope, is found 
 to consist of minute scales and needles suspended in the alcoholic liquid. 
 When the mass is filtered off and dried, it shrinks very much, and is converted 
 into a coherent cake, which has a waxy lustre, is translucent, friable, and 
 lighter than water, and does not soften when kneaded between the fingers. 
 A specimen of the substance from East Indian cotton, when heated in the usual 
 manner in a capillary tube, was found to melt at 86° C. to a transparent 
 liquid, which solidified again at 81° C. Another specimen, from American 
 cotton, fused at 86°, and became solid again at 82° C. According to Avequin, 
 cerosine fuses at 82° and solidifies at 80°. Carnauba wax, according to Lewy, 
 melts at 83 - 5- When heated on platinum foil, cotton-wax gives off an odour 
 resembling that of burning fat, and then burns with a bright flame, without 
 leaving any ash. If heated in a tube, it melts, emits a penetrating odour, and 
 then volatilises completely, yielding an oily sublimate, which soon becomes 
 solid and crystalline and seems to consist of unchanged substance. Singular 
 to say, cotton-wax, when pure, is quite insoluble in caustic alkalies ; and it is 
 therefore difficult to account for its presence among the products extracted 
 from cotton by soda-lye, unless it be assumed that it exists originally, not 
 within the fibre, but on its surface, and is merely fused and mechanically 
 detached by the action of the hot liquid. When treated with boiling dilute 
 caustic soda-lye, it melts without dissolving, and the filtered liquid gives only 
 a trifling precipitate with acid ; but when carefully heated with hydrate of soda, 
 it yields a compound which is entirely soluble in water ; and the solution now 
 gives, with acid, a copious white flocculent precipitate, which consists of a true 
 fatty acid, formed by a process similar to that of ordinary saponification, or 
 more so perhaps to that by which alcohols are converted into the corresponding 
 acids. When cotton-wax is treated with fuming nitric acid, it does not dis- 
 solve, even when the acid is boiled for some time ; it merely melts, and 
 solidifies on cooling. But a change has, nevertheless, taken place ; for if the 
 excess of acid be poured off, and the undissolved fatty matter, after being 
 washed, be treated with boiling caustic soda-lye, it dissolves entirely, and the 
 solution gives, with acid, a white flocculent precipitate. By the action of 
 nitric acid, therefore, the substance is probably transformed in the same 
 manner as by the action of dry caustic soda. 
 
 In order to prepare the substance for analysis, it was kept in a state of 
 
 * Philosophical Transactions for 1811, p. 261. 
 + Journ. f. Prakt. Chemie, B. xxxvi.. S. 65. 
 
COTTON- WAX. 35 
 
 fusion in the water-bath for several hours, then reduced to powder and placed 
 
 in a bell over sulphuric acid. Its analysis yielded numbers corresponding in 
 
 ioo parts to — 
 
 I. II. III. 
 
 C 80-35 80-29 80-38 
 
 H I4-35 14*23 14*51 
 
 O 5*30 5*48 5" 
 
 ioo-oo ioo-oo ioo-oo 
 
 It would have been easy to devise a formula corresponding to these numbers ; 
 
 but as the quantity of material at Dr. Schunck's disposal was not sufficient to 
 
 enable him to make any experiments to determine the atomic weight of the 
 
 substance, the accuracy of any such formula would have been a mere matter of 
 
 probability. That its composition is very similar to that of other vegetable 
 
 waxes will be seen by comparing the above numbers with those obtained by 
 
 Dumas* in the analysis of cerosine, and by Lewyt in that of Carnauba wax, 
 
 which were as follows : — 
 
 Cerosine. Carnauba Wax. 
 
 C 81-00 .. .. 80-36 
 
 H 14-16 .. . . 13-07 
 
 O 4-84 •• •• 6'57 
 
 ioo-oo ioo-oo 
 
 Its composition differs also but little from that of the wax-like body derived 
 from the Ceroxylon andicola. 
 
 For the purpose of examining the product of decomposition which is obtained 
 from cotton-wax by the action of dry caustic alkalies, Dr. Schunck took some 
 of the substance, added caustic soda-lye, evaporated to dryness, and heated 
 the dry residue rather strongly, then added water and evaporated again, 
 repeating the process several times, until the product was found to be entirely 
 soluble in water. An excess of acid was then added ; the matter left undis- 
 solved was filtered off, washed with water, and dissolved in a little boiling 
 alcohol. The solution on cooling deposited white crystalline flocks, which, 
 after being filtered off and dried, had the appearance of a white opaque mass 
 resembling stearic acid. This mass, when examined under the microscope, 
 was found to consist of minute star-shaped aggregates of needles. When 
 heated it was easily volatilised, yielding an oily sublimate which became 
 crystalline on cooling. It dissolved easily in alkaline liquids, and the solutions 
 frothed on being boiled. The solution in ammonia gave, with chloride of cal- 
 cium, a white curdy precipitate. In boiling water it melted, forming trans- 
 parent oily drops, which became solid and crystalline on cooling. In a 
 capillary tube, it fused at 85 C. and solidified at 77 C. The quantity of 
 substance was just sufficient for one analysis. 
 In 100 parts it contained — 
 
 C 79-86 
 
 H 1404 
 
 O 610 
 
 ioo-oo 
 
 * Annales de Chim. et i!e Phys., t. lxxv., p. 223. 
 + Journ. f. Prakt. Chemie, B. xxxvi., S. 74. 
 
 n 2 
 
36 DYEING AND CALICO PRINTING. 
 
 The composition of this substance does not differ very widely from that of 
 cerosic acid, the acid formed by the action of dry potash and lime on cerosine, 
 which, according to Lewy, consists of — 
 
 C 8o-ii 
 
 H *355 
 
 O 634 
 
 IOO'OO 
 
 There can be little doubt that cotton-wax is identical with the " resin " 
 which, according to Persoz and others, is peculiar to cotton, and which is 
 said to protect the filaments from the action of external agents. Dr. Schunck 
 inclines to the belief that it is formed on the exterior of the fibres, and clothes 
 them with a thin waxy covering (like the coating of a similar material some- 
 times found on leaves and fruit), and thus imparts to them their well-known 
 property of resisting water. If it be supposed to be contained solely in the 
 interior of the cells forming the fibres of cotton, it is difficult to conceive by 
 what means any portion of it comes to be dissolved in the alkaline lye, in 
 which, when pure, it is quite insoluble. Its solubility in alkalies is not pro- 
 moted in any appreciable degree by admixture with the colouring matters of 
 cotton ; for on adding to it a quantity of either of the two colouring matters, 
 and acting on the mixture with alkali, the colouring matter is simply dissolved, 
 leaving the wax behind. 
 
 The quantity of cotton-wax obtained in the experiments was exceedingly 
 small. It amounted to about 1 per cent of the weight of the brown precipitate 
 thrown down by acid from the alkaline extract. It is by no means certain, 
 however, that this was the total quantity contained in the cotton. 
 
 Fatty Acid from Cotton. 
 This substance, when prepared in the manner above described, has the 
 appearance of a white mass consisting of microscopic needles arranged in 
 spheres. It fuses at 55'5 C, and solidifies again at 5o - 5° C. When heated on 
 platinum it melts, and then burns with a highly luminous flame. Heated in a 
 tube, it is volatilised, leaving hardly any residue and furnishing an oily sublimate 
 which soon becomes solid. It dissolves readily in alcohol and ether. The alco- 
 holic solution reddens litmus paper slightly. It dissolves in warm caustic potash 
 and soda-lye, as well as in liquid ammonia ; and the solutions froth on being boiled. 
 The solution in potash yields, on cooling and standing, a quantity of crystal- 
 line needles, while the solution in soda gives immediately a thick soap which 
 fills the whole liquid. The solution in ammonia deposits, on cooling, shining 
 crystalline scales. The compound with soda is obtained in a state of purity 
 by adding carbonate of soda to the alcoholic solution of the acid, evaporating 
 to dryness, treating the residue with boiling absolute alcohol, filtering, and 
 evaporating. When this compound is dissolved in boiling water, and the 
 solution is allowed to cool, it is deposited again as a gelatinous mass, which, 
 when examined under the microscope, is found to consist of small needles, 
 arranged in star-shaped or fan-shaped masses. The watery solution gives 
 v. ith the chlorides of barium and calcium white flocculent precipitates, with 
 acetate of lead an abundant white precipitate, and with nitrate of silver a 
 white flocculent precipitate which becomes only slightly discoloured on 
 
COLOURING MATTER IN COTTON. 
 
 37 
 
 exposure to light or on heating the liquid. The alcoholic solution of the acid 
 gives, with acetate of baryta, a white granular precipitate, which is soluble, 
 though with difficulty, in boiling alcohol. With acetate of magnesia it gives 
 at first no precipitate ; but after some time a white crystalline deposit is formed, 
 consisting of the magnesia compound. These reactions belong to the group of 
 fatty acids of which stearic and palmitic acids are members. In order to 
 ascertain the exact place in the series occupied by the acid/rom cotton, it_|was 
 submitted to analysis, the following being the results obtained : — 
 
 Calculation. 
 
 C 3+ 204 75-55 
 
 H 34 34 12-59 
 
 4 32 n-86 
 
 270 ioo-oo 
 
 I. 
 75-27 
 
 i2-gi 
 11-82 
 
 II. 
 
 75"45 
 13-21 
 
 "'34 
 
 ioo-oo 
 
 The formula C3 4 H 34 4 belongs to margaric acid, one of the products derived 
 from ordinary fats. Modern researches have rendered it almost certain that 
 what was formerly called margaric acid is in fact a mixture of stearic and 
 palmitic acids. In consequence, however, of the minute quantity of the sub- 
 stance obtained from cotton, Dr. Schunck was unable to undertake any experi- 
 ments for the purpose of separating its constituents from one another, but was 
 obliged to content himself with proving the presence of one of the ordinary 
 products of the saponification of fats and oils among the bodies extracted from 
 cotton by alkalies. The quantity procured from American cotton was, indeed, 
 so small that he was hardly able to purify it sufficiently for the purposes of 
 analysis, and the amount of hydrogen which it was found to contain differed 
 accordingly rather widely from that demanded by theory ; the presence of 
 some impurity or other in this specimen was also indicated by its rather lower 
 melting-point. 
 
 As regards this fatty acid, the question will naturally arise, whether it is to 
 be considered a natural constituent of the fibre, or whether it is a foreign 
 body introduced subsequently to the gathering of the cotton, either before 
 or during the process of manufacture ; but this is a question to which 
 it is not easy to give a satisfactory reply. Persons practically conversant 
 with cotton spinning say that it is impossible for the cotton to be con- 
 taminated with any substance of a fatty nature during the process of its 
 conversion into yarn, provided ordinary care be taken, since it can only in 
 consequence of gross carelessness come into contact with the oil or fat used in 
 greasing the machinery. On the other hand, it is quite possible that after 
 the cotton has been gathered, especially during the process of ginning, a 
 portion of the oil of the seed may escape, diffuse itself among the fibres, and 
 give rise to the formation of fatty acid in consequence of the action on it of 
 the alkali. Dr. Schunck has not, however, failed in any of his experiments, 
 whether made with East-Indian or American cotton, to obtain a small quantity 
 of a solid crystalline fatty acid. 
 
 Colouring Matter A. 
 This substance is easily soluble in alcohol and is left on evaporating the 
 solution as a dark brown, shining, brittle, amorphous resin, which is transparent 
 in thin layers. In boiling water it softens and melts to a pasty mass, which 
 
mm^wx^^^^M, ffi 
 
 
 
 38 
 
 DYEING AND CALICO PRINTING. 
 
 becomes hard and brittle again on cooling. It is insoluble in ether, and is 
 accordingly precipitated on the addition of ether to the alcoholic solution. 
 When heated on platinum it melts, swells up considerably, and burns with a 
 bright, but smokeless flame, leaving a very voluminous coal, which gradually 
 burns away, only a slight trace of ash being left. It contains nitrogen, and 
 when heated with soda-lime gives off ammonia in abundance. It dissolves 
 in concentrated sulphuric acid and in glacial acetic acid, giving dark brown 
 solutions, from which it is re-precipitated by water in brown flocks. It is 
 easily decomposed by boiling nitric acid, yielding a yellow solution, which on 
 evaporation leaves an abundance of oxalic acid, but no picric acid. It is 
 easily soluble in caustic and carbonated alkalies, giving dark yellowish-brown 
 solutions, from which it is re-precipitated by acids in light brown flocks. 
 The ammoniacal solution leaves, on evaporation, a dark brown amorphous 
 residue, which does not dissolve again entirely in water, in consequence of a 
 loss of a part of its ammonia during evaporation. The ammoniacal solution 
 gives brown precipitates with the chlorides of barium and calcium, but none 
 with sulphate of magnesia. With nitrate of silver it yields a dark reddish- 
 brown precipitate, which dissolves completely in an excess of ammonia, giving 
 a yellowish-brown solution, which remains unchanged on being boiled. The 
 alcoholic solution of the substance gives brown precipitates with the acetates 
 of baryta, lead, and copper. On the addition of an alcoholic solution of 
 potash it gives a brown precipitate, which sinks rapidly, forming a glutinous 
 deposit. A similar effect takes place when an alcoholic solution of soda is 
 employed. The substance is easily soluble in a boiling solution of acetate of 
 soda, and is re-precipitated by acids in brown flocks. When the substance 
 in a finely divided state, as obtained by precipitation from its alkaline solution 
 with acid, is exposed for some time to the action of chlorine, its colour changes 
 gradually from brown to pale yellow. After being filtered off and washed 
 with water, the product of the action dissolves easily in alcohol, and is left on 
 evaporation as a brown transparent resin, which contains chlorine, but in 
 other respects closely resembles the original substance. 
 
 The analysis of this colouring matter led to results corresponding in 100 
 parts to — 
 
 C .. ,. 
 
 H .. .. 
 
 N .. .. 
 
 O .. .. 
 
 It will be seen that the composition of the substance varied, especially as 
 regards the nitrogen, much more than it ought to have done, supposing it to have 
 been perfectly pure. In consequence of the amorphous nature of the product, 
 it is difficult to determine whether Indian and American cotton contain two 
 distinct colouring matters, both easily soluble in alcohol and having the same 
 general physical properties, or whether in one or both cases the specimens 
 submitted to analysis, though essentially the same substance, were not 
 chemically pure. It is difficult to obtain, in a state of purity, an uncrystal- 
 lisable resinous body having few characteristic properties ; and the results 
 arrived at by examining the composition of such bodies aie seldom satisfactory. 
 
 I. 
 
 II. 
 
 III. 
 
 IV. 
 
 58-27 
 
 58-11 
 
 58-36 
 
 58-48 
 
 6-42 
 
 6-40 
 
 5'9Q 
 
 5-80 
 
 8-03 
 
 — 
 
 5-22 
 
 5'3i 
 
 27-28 
 
 
 30-S2 
 
 30-41 
 
 lOO'OO 
 
 ioo-oo 
 
 IOO'00 
 
COLOURING MATTER IN COTTON. 
 
 39 
 
 Colouring Matter B, 
 
 This substance is deposited from its solution in boiling alcohol as a brown 
 powder, which, after being filtered off and dried, forms coherent masses of 
 a colour varying from light to dark brown, which may be easily broken, the 
 fracture being dull and earthy. In boiling water it softens and yields a dark 
 brown cake. It is almost insoluble in cold alcohol, and when it has once 
 been dried it dissolves with great difficulty even in boiling alcohol. By this 
 property it may easily be distinguished from the other colouring matter, which 
 it closely resembles in most other respects. When heated on platinum, it 
 burns without previously melting ; and the carbonaceous residue burns away 
 with difficulty, leaving at last a bulky white or yellowish ash. This ash is not 
 alkaline, and consists principally of alumina and sulphate of lime. The ash 
 was in most cases so considerable that Dr. Schunck was led to suspect that 
 this colouring matter might possibly be a compound of the other with some 
 earthy base, in which case the striking similarity in the properties and 
 reactions of the two substances would have admitted of an easy explanation. 
 In order to submit this supposition to the test of experiment, he took some 
 of the colouring matter B, pounded it very fine, added a little concentrated 
 sulphuric acid and then absolute alcohol, after which the whole was well stirred 
 in a mortar and left to stand for some time. The liquid, which had a brown 
 colour, was filtered and mixed with water, which gave a brown precipitate. 
 This was filtered off, washed with water, and dissolved in boiling alcohol. The 
 solution left, on evaporation, a brown resinous residue, which was almost 
 insoluble in cold alcohol, and contained, therefore, none of the colouring 
 matter A. 
 
 In determining the composition of this substance, results were obtained 
 which, after deducting the ash, correspond in ioo parts to — 
 
 I. 
 
 C 57-28 
 
 H 625 
 
 N 9'39 
 
 O 27-08 
 
 II. 
 
 57'53 
 626 
 
 9"59 
 2662 
 
 III. 
 
 57"32 
 
 6-32 
 
 9"53 
 
 26-83 
 
 IV. 
 
 58-47 
 
 577 
 
 777 
 
 27*99 
 
 V. 
 
 58-26 
 5-65 
 7-43 
 
 2866 
 
 Mean. 
 
 5777 
 6-05 
 8-74 
 
 27-44 
 
 ioo-oo 
 
 It will be seen that in this case, as in that of colouring matter A, there is 
 a wider discrepancy in the numbers yielded by analysis than ever takes place 
 with a perfectly pure substance. Nevertheless the composition of colouring 
 matter B, as represented by the mean of the numbers just given, approaches 
 so closely that of colouring matter A from East-Indian cotton as to make it 
 probable that, when pure, the two bodies do not differ in composition from one 
 another.* 
 
 From what has just been stated it may be inferred that, as regards their 
 chemical properties, these colouring matters possess very little interest. It is 
 simply the fact of their being the cause of the yellow or brownish tinge 
 natural to raw cotton which gives them any importance, and makes a 
 
 1 It is quite possible that these colouring matters maybe produces of decomposition derived 
 from some other substance existing in the fibre, and that they may consequently vary in 
 composition according to the strength of the solvent used for extraction, the time during 
 which it acts, and other circumstances. 
 
4Q 
 
 DYEING AND CALICO PRINTING. 
 
 knowledge of their properties desirable from a practical point of view. The 
 darker shade of colour seen in the so-called " nankin " cotton is probably due 
 to a great excess of these colouring matters existing in the fibre. It is certainly 
 not caused by oxide of iron, since the ash of this kind of cotton contains no 
 more iron than that of ordinary kinds, and the colour is for the most part re- 
 moved by treatment with caustic alkali. 
 
 Pectic Acid. 
 
 A considerable portion of the organic matter extracted from cotton by caustic 
 alkali consists of a body belonging to the pectine class. Which member of 
 this class it is that exists originally in the fibre is a question on which no 
 opinion is expressed, though there can be no doubt that the precipitate pro- 
 duced by acid in the alkaline extract of cotton contains pectic acid itself. 
 This acid, which is insoluble in water, is almost entirely converted during the 
 process of purification adopted into an acid soluble in water, which seems to 
 be identical with Fremy's parapectic acid. The chief properties of this soluble 
 acid are as follows : — 
 
 On evaporation it is left as alight yellow, amorphous, translucent substance 
 resembling gum or gelatine. When heated on platinum it burns with a slight 
 flame, without previously melting, leaving a little ash, which is yellow or 
 brown and only slightly alkaline, and consists chiefly of alumina, together 
 with oxide of iron and lime. The watery solution is clear and colourless and 
 reddens litmus-paper. It gives abundant white flocculent precipitates with 
 sulphuric, nitric, hydrochloric, and acetic acids, as well as with baryta water and 
 acetate of lead. When the watery solution is mixed with several times its 
 volume of alcohol the liquid gelatinises, the jelly being perfectly clear and 
 transparent. The substance is decomposed with difficulty by boiling nitric 
 acid ; and no oxalic acid can be discovered among the products of decom- 
 position. When treated with strong caustic potash or soda-lye it turns yellow ; 
 and on boiling, the liquid assumes a bright yellow colour similar to that of 
 chromate of potash solution. On continuing the action of the caustic alkali the 
 substance is gradually dissolved; but on adding an excess of acid no precipitate 
 is produced, showing that a complete change has taken place. In very dilute 
 potash or soda-lye, as well as in liquid ammonia, it dissolves readily on 
 boiling. The solutions when mixed with alcohol give colourless jellies, con- 
 sisting of the salts of the respective bases. If the precipitated ammonia 
 compound, after being filtered off and washed with alcohol until the excess of 
 ammonia is removed, be treated with boiling water, it dissolves, and the 
 solution leaves, on evaporation, a transparent, amorphous, nearly colourless 
 residue, which separates from the sides of the vessel in shining scales. This 
 residue dissolves again entirely in water. The solution is neutral to test- 
 paper, and gives flocculent precipitates with alkaline salts, such as chloride 
 of sodium and chloride of ammonium, as well as with all earthy and metallic 
 salts which were tried, except perchloride of mercury and chloride of gold. 
 The precipitate with nitrate of silver, which is white, does not change much 
 when exposed for several days to light, and when dissolved in ammonia yields 
 a solution which on being boiled becomes yellow but deposits no metallic 
 silver. When a solution of the acid in a sealed tube is heated for some time 
 in the water-bath it is found to have undergone a complete change. The 
 
PEC TIC ACID. 41 
 
 liquid leaves, on evaporation, a brown, slightly deliquescent residue, which 
 dissolves again with ease in cold water. The solution has a strong acid 
 reaction. With caustic alkalies it strikes a deep yellow colour. It gives 
 flocculent precipitates with baryta-water and acetate of lead, but none with 
 hydrochloric acid or chloride of sodium. With nitrate of silver it gives a 
 precipitate which blackens on exposure to light, and when made alkaline it 
 reduces oxide of copper at the boiling-heat. The acid has, in fact, been con- 
 verted into the substance, or mixture of substances, to which Fremy has given 
 the name of metapectic acid. 
 
 The reactions just described are of themselves almost sufficient to prove 
 that the acid obtained from cotton is one of the derivatives of pectine. All 
 uncertainty on this point, however, was removed by an examination of its 
 composition, which, if the ash be deducted and the small amount of nitrogen, 
 which evidently belonged to some slight impurity, be neglected, led to the 
 
 following numbers : — 
 
 I. II. III. 
 
 C 40-91 39-98 39-82 
 
 H 4-81 475 4-88 
 
 O 54-28 55'27 55*30 
 
 IOOOO IOO'OO IOO'OO 
 
 The results arrived at by different chemists in examining the composition 
 of pectine and its derivatives vary so much that it is difficult to identify any 
 member of the class by means of analysis only. The composition just given 
 approaches that of Fremy's parapectic acid, which, according to him, consists of 
 
 C 41-67 
 
 H 4*97 
 
 O 5336 
 
 IOO'OO 
 
 It has been already mentioned that the acid originally contained in the 
 alkaline extract of cotton is insoluble in water, but is gradually converted 
 during the process of purification into a soluble acid. Of the insoluble acid, 
 the true pectic acid, a sufficient quantity for the purposes of analysis was 
 obtained on only one occasion. It was left undissolved by boiling water in 
 the preparation of the specimen of soluble acid employed for the second of 
 the above analyses, and when dry was dark grey and horn-like, and was with 
 difficulty reduced to powder. 
 
 After deducting the ash, it gave numbers corresponding in 100 parts to — 
 
 C 42*09 
 
 H 503 
 
 According to Chodnew,* pectic acid contains in 100 parts — 
 
 C 42*22 
 
 H 524 
 
 52*54 
 
 Fremy's experiments led him to infer that there exists in plants a body 
 insoluble in water, which he calls pectose, and which, by the action of acids, 
 
 + Annalen d. Chem. u. Pharm., B. li., S. 163. 
 
42 
 
 DYEING AND CALICO PRINTING. 
 
 alkalies, or the pe<5Hc ferment (pectase), is converted first into pectine, then 
 into pectic acid, and other produces in succession. It is not improbable that 
 this may be the case with cotton fibre also ; but as yet no experiments have 
 been made to decide this point. 
 
 Pectic, parapectic, and metapectic acids have recently been discovered by 
 Divers and Abel among the products of the spontaneous decomposition of 
 gun-cotton ; and the latter maintains that " these substances have been so 
 frequently obtained, that they must be regarded as general products of the 
 gradual decomposition of gun-cotton." If from this we are to infer that the 
 acids named are derived from nitro-cellulose itself, Dr. Schunck thinks it will 
 be granted that there is little probability in the supposition, and that it is 
 safer to assume that these acids pre-existed in the cotton fibre, in the form of 
 pectine or pectic acid, before the action of nitro-sulphuric acid on it. 
 
 According to Fremy, the pectic acid of plants is always accompanied by a 
 small quantity of an albuminous substance. It seemed not improbable that 
 this might also be the case with the pectic acid of cotton ; but as the pre- 
 paration in a state of purity of a body of this class when occurring along with 
 the other constituents of cotton fibre would without doubt have been a very 
 difficult task, it was determined to ascertain whether, by the action of caustic 
 alkalies on the impure pectic acid of cotton, any of the products of decom- 
 position of albumen could be procured, some of which are bodies of very 
 characteristic properties. For this purpose a quantity of the brown precipitate 
 thrown down by acid from an alkaline extract of cotton was exhausted as 
 far as possible with boiling alcohol ; it was then dried, a quantity of hydrate of 
 soda, equal in weight to that of the dry residue, together with a little water 
 added, and the mixture heated over the fire in an iron ladle, with the 
 precautions which are usually observed in the preparation of leucine and 
 tyrosine from animal matters. The decomposition was accompanied by a 
 copious evolution of gas and a strong smell of ammonia, the latter being 
 probably derived for the most part from the colouring matter present, which 
 had not been completely removed by the alcohol. The disengagement of 
 gas having ceased, the mass was treated with boiling water, in which it 
 dissolved almost entirely, yielding a dark brown solution. To this there was 
 added an excess of acetic acid, which gave a brown flocculent precipitate. 
 This having been filtered off, the liquid was evaporated. During evaporation 
 it deposited a considerable quantity of a brownish-white crystalline powder, 
 consisting of oxalate of soda. This was filtered off, purified by re-crystallisation 
 from boiling waLei, and converted into oxalate of lead, from which there was 
 obtained, in the usual manner, a quantity of pure crystallised oxalic acid, 
 weighing 18-3 grms. The mother-liquor of the oxalate of soda was evaporated. 
 It left a dark brown syrup, which was dissolved in boiling alcohol, and mixed 
 with concentrated sulphuric acid as long as any sulphate of soda was pre- 
 cipitated. The latter having been filtered off, acetate of lead was added, and 
 the liquid, after being filtered from the precipitated sulphate of lead, was 
 deprived of its excess of lead by means of sulphuretted hydrogen, filtered 
 again, and evaporated. The brown syrup which remained was mixed with a 
 large quantity of alcohol and left to stand for several weeks. During this period 
 the liquid gradually deposited a quantity of white crystalline needles, which, 
 after being filtered off, washed, and dried, weighed 06 grm. These crystals 
 
PEC TIC ACID. 
 
 43 
 
 possessed the properties of tyrosine, and were quite free from leucine. Now 
 as tyrosine is only formed, as far as we know, from albumen and bodies of the 
 same class, it is almost certain that cotton contains a small quantity of 
 an albuminous substance. The oxalic acid obtained in this experiment was 
 doubtless derived from the pectic acid. Of the ratio in which the latter stands 
 to the albuminous matter, some estimate may be formed by that subsisting 
 between their respective products of decomposition. 
 
 The precipitate produced by acid in an alkaline extract of cotton contains, 
 then, the following organic substances : — 
 
 i. Cotton wax. 
 
 2. Margaric acid. 
 
 3. A colouring matter easily soluble in alcohol. 
 
 4. A colouring matter sparingly soluble in alcohol. 
 
 5. Pectic acid. 
 
 6. Albuminous matter. 
 
 Of these various bodies the pectic acid far exceeds the others in quantity. 
 Then follow the colouring matters. The three other constituents are present 
 in extremely minutes quantities only. Dr. Schunck thinks it possible that 
 cotton fibre may contain, besides these, other organic substances which 
 are soluble in water or alkali, but are not afterwards precipitated by acid. 
 It is well known that cotton, during the process of bleaching, loses about 
 5 per cent of its weight, whereas the total weight of all the substances obtained 
 in Schunck's experiments amounts to hardly £ per cent. It is, however, not 
 improbable that a portion of the matter which escaped observation may con- 
 sist in great part of parapectic acid. This body, though insoluble in tolerably 
 strong acids or saline solutions, is soluble in pure water. When, therefore, it 
 is precipitated from an alkaline solution, the precipitate, on being filtered off 
 and washed, begins gradually to dissolve as soon as the greatest part of the 
 precipitant has been removed. This was observed on washing the precipitate 
 thrown down by acid from the alkaline extract of cotton. When the acid has 
 to some extent been removed, the wash-water begins to becomes thick and 
 slimy, and runs through very slowly, in consequence of its dissolving a portion 
 of the parapectic acid of the precipitate. A part also of the pectic acid 
 originally present may undergo a further change by the action of the alkali, 
 and be converted into the metapectic acid of Fremy, which is very soluble in 
 water, and is not precipitated by stronger acids. The loss of weight sustained 
 by cotton during its treatment with alkali, and not accounted for by Schunck's 
 experiments, may therefore be due to such derivatives of pectine as are not pre- 
 cipitated by acid, or are subsequently removed by washing the precipitate with 
 water. 
 
(44) 
 
 CHAPTER IV. 
 
 BLEACHING. 
 
 BEFORE either spun cotton yarn orwoven tissue are fit for dyeing or printing, 
 they undergo a series of mechanical and chemical processes to free them 
 from all adhering substances, such substances either naturally belonging to the 
 fibre or being purposely introduced during the operations of spinning and weaving. 
 Pure cotton is of a dirty yellow colour, which if not removed by bleaching 
 would materially affect and change the brighter shades of dyes imparted to 
 tissues ; moreover, the effect of many beautiful printed patterns is due to the 
 brilliant white ground upon which they appear. Bleaching also removes 
 from cotton all grease, which if allowed to remain would prove very injurious 
 both in dyeing and printing, either preventing the fixation of colour, or else 
 adtinc as a mordant, especially after partial oxidisation by the air, and thus 
 attracting the dye in an irregular manner. 
 
 Before bleaching, the cotton fabric is singed, in order to remove the nap and 
 render the surface perfectly smooth. This is done either by passing the fabric 
 through a gas flame or over a heated copper plate. In the latter case there 
 was formerly great waste of fuel in maintaining the heat of the plate owing to 
 its free radiation into the atmosphere, but this has been remedied by an in- 
 vention of Mr. Thorn. This consists of enclosing the plate in a brick arch so 
 that no air can enter the chamber except that passing in with the stuff, and 
 the limited quantity thus admitted is conducted by flues into the furnace 
 which heats the plate. Messrs. Joshua Schofield and Sons have introduced a 
 new gas singeing machine, patented by Mr. James Cook. Instead of the 
 fabric being drawn through the flame as in the old method, the flame is made 
 to flow upon the surface of the fabric, the nap being thereby removed without 
 destroying the fibres. The flame employed in this method is a mixture of 
 coal-gas and oxygen, the heat of which is so great that the fabric can be passed 
 over it with such rapidity as to remove the nap without injuring the fibre. 
 The machine is both quick and economical, and like Mr. Thorn's, does not 
 allow of the escape of any offensive odour during the operation. At the 
 works of Messrs. Edmund Potter and Co. more than 4000 pieces of calico were 
 singed in a day with a consumption of only 1000 cubic feet of gas per 1000 
 pieces. 
 
 The following substances adhere to and become mixed up with the cotton : — 
 1st, a brown-coloured incrustating substance insoluble in water and alkaline 
 solutions, but capable of becoming soluble in water under the joint influence 
 of air, damp, and sunlight, or by the action of chlorine and hypochlorous acid ; 
 2nd, according to M. Penot, a resinous substance soluble in alkaline lyes ; 
 but the quantity of both these substances found in cotton is small. 
 
BLEACHING. 
 
 45 
 
 The following substances are also imparted to cotton fabrics by the operations 
 of spinning and weaving: — ist, starch and paste; 2nd, fatty matters ; 3rd, a 
 soap of copper (due to the action of the fatty substances upon the copper 
 teeth of the comb); and 4th, of dirt from the hands of the operatives. It is 
 impossible to act upon the incrustating matters until after the removal of the 
 last-named impurities, for which purpose alkaline lyes are resorted to. These, 
 besides eliminating grease and dirt, promote the removal of incrustating 
 matters by predisposing them to oxidisation. Cotton is easier to bleach than 
 any other fibre, because it contains but few impurities and consists mainly of 
 cellulose, which resists uninjured the action of pretty strong chemicals, so 
 that energetic agents may be safely employed. Wool and silk cannot be 
 so actively treated. The theory of bleaching is that the greasy matters are 
 removed by caustic or carbonated alkaline lyes, while the incrustating sub- 
 stances are destroyed by an oxidating process ; its practice consists of the 
 following operations : — " Singeing," " rot steep " or " wetting-out steep," 
 " liming," passing through a solution of chloride of lime, "bowking," passing 
 through weak acids, chiefly hydrochloric acid, washing, squeezing, and dyeing. 
 The " rot steep," so called because the flour or size with which the goods were 
 impregnated was formerly allowed to ferment and putrefy, is intended to 
 thoroughly wet the cloth. This takes some time, as the fabric, on account of 
 the greasy matters contained in it, throws off the water in places, and if it be 
 not thoroughly wetted there is risk of irregularity in the after processes. 
 " Liming " takes place in large kiers or kettles capable of holding from 500 
 to 1500 pieces of cloth. The lime is carefully slaked some days previous to 
 use, and sifted to prevent the introduction of small lumps of quick-lime into 
 the kiers into which it is equally distributed : the stuff is then pressed down 
 into the kiers, and the boiling commenced and continued for a period of from 
 twelve to sixteen hours. After this the liquor is drawn off and clear water 
 run in to cool the pieces, which are then taken out and washed. Liming 
 usually takes place at low pressure, but a patent process, which employs a 
 pressure of upwards of 40 lbs., appears to answer very well and saves time. 
 It is very important that the goods remain entirely covered with liquid during 
 this operation, since, according to Dr. E. Schwartz, the action of lime upon 
 cloth is highly destructive if it be at the same time exposed to the air. The latest 
 of the methods of bleaching under pressure is that of Mr. Barlow. Of this method 
 and the machinery employed we give illustrations. In that of Mr. Barlow's, 
 Fig. 1 is an elevation showing a pair of kiers, fitted with distributers, &c. 
 A and B are the kiers (which it is preferable to make of strong boiler-plate 
 iron), the kier a being shown in section, and exhibiting the distributors, &c. 
 
 At the bottom of the kier is a plate of an umbrella shape, c. This plate 
 spreads over about three-fourths of the bottom of the kier ; it is perforated 
 with holes all around its outer ridge, at d d, which rests upon the bottom of 
 the kier ; all the rest of the plate being solid. This plate is fastened in the 
 centre to an iron block, e, which stands upon the bottom of the kier, in the 
 centre, over the outlet hole. The block c is pigeon-holed at the bottom, so as 
 to allow the liquor to pass from the kier. A socket is left in the upper part of 
 the block e, to admit the insertion of the distributor,/. This distributor is 
 made of dimensions corresponding to the size of the kier; it is solid for some 
 distance from the bottom, and above that is hollow and perforated as full as 
 

 BRMfe4#^&w**vS? 
 
 
 46 
 
 DYEING AND CALICO PRINTING. 
 
 possible with holes until within a few inches of the top of the kier, where it 
 is connected with the tap g (an ordinary two-way tap, which admits either 
 steam or liquor, or shuts off both) by an inlet pipe, which dips for some 
 distance inside the distributor. is the pipe connecting the top of the kier A 
 with the bottom of kier b, and p p is the pipe which connects the top of kier b 
 with the top of kier a ; q q are steam-pipes from the main-pipe, r ,• in is the 
 manway, through which the goods are introduced and removed ; n the pipe 
 and tap, through which the working liquor enters the kier ; s s are gauges, by 
 which it is seen when the liquor has passed from one kier and has entered the 
 
 Fig. 1. 
 
 fnflE=2> 
 
 other; k k are draw-off taps connected with the pipes and p, by which the 
 kiers can be emptied of spent liquor, water, &c. 
 
 In operating with this apparatus, the goods are introduced through the 
 manways, laying them at the bottom, upon the umbrella plate and the 
 bottom of the kier; the kiers are filled to the top, and the manways closed. 
 Steam (a high pressure preferable) is then admitted, through the two-way 
 taps, g g, from the pipes q q into the kiers ; the steam forces all the cold 
 water, air, &c, out of the goods (being very much assisted in its action by the 
 distributor) through the perforated edge of the umbrella plate, at d d, the holes 
 
tiLE ACHING. 
 
 4? 
 
 irt the block e, and out of the kier hy the taps k k ; the taps are then closed. 
 The boiling bowking liquor is next run in, by tap n, to kier u, and steam again 
 admitted, which forces the liquor through the goods out of the kier B, up 
 the pipe o o, and into kier a, its tap, g, being turned to admit the liquor. 
 When all the liquor has passed into kier a, steam is shut off from kier b, 
 turned on to kier a, and, in like manner, forces the liquor through the goods 
 in kier a, up the pipe p p, and into the kier B again. This is repeated until 
 the goods are sufficient)}' worked. 
 
 By this system all the cold water, air, &c, is first expelled, by the high- 
 pressure steam, from the goods, which, then almost dry, and heated by the 
 
 Fig. 3. 
 
 steam, are in the best state for receiving benefit from the bowking liquor, 
 -which is admitted boiling, is forced through them, and followed up by 
 the steam ; and throughout the whole of the operation they are subjected 
 alternately to the action of the steam and the liquor. By this alternate 
 steaming and liquoring, the goods are much more thoroughly cleansed than has 
 been the case in former kiers. 
 
 Fig. 2 is a modification of Fig. i. The various parts of the kiers correspond 
 with the description of Fig. i ; the principle and the mode of working are 
 
DYEING AND CALICO PRINTING. 
 
 
 precisely the same ; the only difference is, that kier b is reduced in size 
 to about one-third that of kier a ; it is not charged with goods, and is only 
 intended to receive the liquor when forced through the goods in kier a. The 
 liquor is boiled in kier b by a modified distributor, and is forced from it into 
 kier a, and this is repeated until the goods in kier a are sufficiently worked. 
 
 This modification is only recommended where small quantities are done, 
 and the kiers required would be too small for working in conveniently. 
 Where quantities above 300 pieces, or say 1,500 lbs. of goods a day are done, 
 it will be very much better to adopt the double kiers, as in Fig. 1 ; for they 
 take up very little more room, require only the same attendance, and, with 
 the exception of a few feet of piping, they need only the same pipes, taps, 
 gauges, and other fittings, so are not much more expensive to put up than this, 
 Fig. 2, while double the quantity can be done in them in the same time, for both 
 kiers can be crammed with goods to the very top. 
 
 Even when there are only sufficient goods to fill one kier it is better to divide 
 them, putting half into each kier, as the liquor is kept hotter, and there is less 
 condensation of steam in working, than when the liquor is forced from the 
 kier charged with goods into an empty one. 
 
 Mr. Kent, of Moscow, Russia, and of Nottingham, has patented an im- 
 provement in cleansing and bleaching, much used by cleaners working on 
 a small scale. The improvement consists in subjecting the cotton-yarn or 
 fabric to the following process : — Lime and soda are mixed (in the proportion 
 of about 2 lbs. of carbonate of soda to 1 lb. of lime) with water, and allowed 
 to stand to settle, when the clear liquor is drawn off or separated from the 
 solid matters. It is found that the strength of the liquor when used should 
 mark about ij degrees of Twaddle's hydrometer. A strength of ii degrees 
 is found sufficient for fine light goods, and for heavier goods a greater strength 
 is required. The yarn, thread, or fabric, or other preparation of vegetable 
 fibres, is steeped in this liquor for from thirty to fifty minutes, more or less, 
 as the case may require. Fine goods require about thirty minutes, and stouter 
 ones a longer time in proportion. The process of cleaning and bleaching is 
 then finished in the ordinary manner by washing, and then treating the fibrous 
 materials with dilute sulphuric or hydrochloric acid and chloride of lime, but 
 this part of the process requires less time, by reason of the fibrous materials 
 not having been boiled for a great length of time with crude materials. A 
 workman will readily judge of the effecT: produced, and he will find that it is 
 not necessary to retain the yarns or fabrics in either of the liquors more than 
 from forty to fifty minutes. By these means ordinary bleaching is accomplished 
 in a few hours instead of occupying days. When the fabrics are to be dyed 
 with madder in order to render them suitable to be so dyed, or as it is 
 commonly called " madder bleached," the fabrics after being steeped and pre- 
 pared as explained, are boiled for two or three hours in a weak solution of 
 carbonate of soda and resin. The greasy matters are formed by the lime 
 into a sort of insoluble soap easily removed by the after process. 
 
 " Souring" removes all excess of lime and breaks up the insoluble lime 
 soap ; it still leaves the grease upon the cloth, but in such an altered state as 
 to be easily removable by the subsequent " bowking." Hydrochloric acid is 
 sometimes employed in this souring, but very dilute vitriol may be used. The 
 hydrochloric acid sours are used cold and at a strength of 3 Twaddle. The 
 
BLEACHING. 
 
 49 
 
 bowking or boiling with alkali and soap dissolves and removes all grease and 
 dirt from the cloth, leaving the cotton nearly pure. The alkali employed is 
 soda-ash ; the soap is that made from prepared resin, and having the specific 
 effect of improving the whites during the subsequent process of dyeing. This 
 boiling need not be so long as the liming, the time required, however, de- 
 pending upon the size of the kier and the number of pieces. The last process, 
 that of passing through a clear solution of bleaching-powder, destroys the 
 slight buff or cream-coloured tinge still adhering to the cotton. The solution 
 of bleaching-powder is so weak that an ordinary sized piece of calico does not 
 probably take up more than a quarter of an ounce of the soluble matter con- 
 tained in it. The goods are allowed to remain some time with the chloride of 
 lime in them, and are finally passed through sours to complete the operation. 
 The acid sets the chlorine free from the bleaching-powder, and completes the 
 destruction of the colour, at the same time removing the lime and acting on 
 any traces of iron that may be in the cloth. This souring should always be 
 made with hydrochloric acid, as it obviates the danger of any sulphate of 
 lime being fixed in the fibres or of giving bad whites in dyeing, effectually 
 removes any iron, and leaves the goods softer. Tables of strengths and 
 proportions of substances employed in bleaching are not of much value, since 
 they must be modified according to circumstances, but as a kind of guide or 
 example the following particulars may be quoted : — For 14,000 yards of gth 
 printing cloth, 66-reed, 250 lbs. of quick-lime were used in the liming; no lbs. 
 of hydrochloric acid for the first souring, and 140 lbs. of soda-ash at 48 per 
 cent alkali, and 80 lbs. of prepared resin, or resin soap made with resin, and 
 caustic alkali were used in the bowking. The last souring was sulphuric acid 
 sour at 3 (37 - 4 F.) The quantity of bleaching-powder was not ascertained, 
 but the solution stood at i° = 1-006 sp. gr. 
 
 Chloride of lime is generally termed chemick in the dye-house, and the 
 solutions are made up to half a degree Twaddle, or 1002-5, but in some 
 establishments this is increased to 5 . There is the danger of rotting the 
 cloth when very strong chemick is employed, the process generally consisting 
 in passing the articles rapidly through with the calender in order to saturate 
 them, and then to pass them through the acid bath, the final operation being 
 the washing. The calender renders the passage through the chemick very 
 rapid, so that strong solutions even for fine goods can be employed. The 
 chemick must be clear, for any pieces or lumps of the chloride of lime coming 
 into contact with the cloth would rot or burn it, as the term runs, leaving 
 holes. The chloride of lime of commerce is a mixture of chloride of calcium 
 and hypochlorite of lime. In the process of oxidising the foreign matters, 
 which it is the purpose of bleaching to remove, the chloride is inefficacious, 
 but the hypochlorite under the influence of the water or that of the carbonic 
 acid of the air sets free oxygen, in its turn rendering the colouring matter 
 soluble ; the oxygen is separated according to the following equation : — 
 
 CaO,C10 = CaCl + 2 , 
 that is, one atom of hypochlorite of lime sets free two atoms of oxygen ; 
 while one atom of free chlorine sets free only one atom of oxygen, according 
 to the equation — 
 
 Cl + HO = HCl + 0. 
 
 We thus see that the mixture known by the name of chloride of lime contains 
 only one-half of its chlorine in effective condition. After the cloth has been 
 

 MIBBBBI 
 
 rftl 
 
 50 
 
 DYEING AND CALICO PRINTING. 
 
 passed through the liquors employed in the process of bleaching it becomes 
 necessary to discharge the fluid, and this operation is effected by squeezing 
 rollers or squeezers. These are rollers generally worked under steam-power, 
 the upper one being caused to bear upon the cloth by its own weight, or by 
 means of a weighted lever. There are many varieties of these machines, 
 the description of which belongs, however, to mechanical engineering, and is 
 not an essential of the chemical processes of bleaching. 
 
 When squeezed, sometimes effected over rollers heated by steam, the cloth, 
 if required for printing, needs no further operation, but if intended for the 
 market it must be " finished," that is, starched and calendered. Many 
 bleachers prefer to prepare their own starch from flour, as they thus avoid the 
 drying process, for which the manufacturer of the starch must be paid. The 
 starch is coloured with blue, generally ultramarine. It is disseminated ever 
 the cloth by means of rollers dipping into the starch, other rollers removing 
 the excess. The starch need net be pure ; fine clay or gypsum is sometimes 
 employed as well. The pieces of cloth are occasionally artificially weighted 
 with sulphate of baryta during the finishing, or with silicate of soda. The 
 object of such an addition is to render the cloth solid in appearance. The 
 calendering machine is really an ironing machine, surface and gloss being 
 imparted to the cloth by means of heated rollers. The pieces when calendered 
 and finished are subjected to hydraulic pressure. 
 
 Bleaching Muslins. 
 
 Muslins are bleached in the same manner as other cotton goods : Mr. 
 Barlow employs solutions of the same strength, and does not consider that 
 muslins need any special treatment. Only in cases where goods have 
 coloured threads woven into them or colours printed on them must great 
 caution be used ; then it is desirable to employ weak solutions, repeating the 
 operation often rather than allowing it to be continued for a length of time. 
 It is possible to perform the entire bleaching in one operation, but then the 
 goods would be made rotten : a certain strength of bleaching solution or soda 
 leaves the fibre unattacked, while a more concentrated solution destroys the 
 fibre as well as the colouring matters. It is often required to bleach the 
 white ground of printed goods, where the ground has taken up sufficient 
 colour to deteriorate the brilliancy of the white, and which soap would be 
 powerless to remove. A solution of bleaching-powder at half a degree 
 Twaddle is then employed. The liquor should be tested with a piece of 
 Turkey-red dyed stuff; if too strong the colour will be discharged. 
 
 Muslins when finished and dried without motion become very hard, rigid, and 
 rough to the touch ; they are therefore stretched during drying, the lines of 
 selvage being moved backward and forward so that the weft threads may 
 rub against each other and not become united. This method of drying imparts 
 the peculiar spring or elasticity to muslins. 
 
 Bleaching Cotton Stockings. 
 We shall from time to time in the progress of this work give descriptions in 
 technical terms of processes which have been found advantageous for special 
 purposes. These descriptions will differ from the rest of the work in being 
 
BLEACHING. Q^^frfZ ** 
 
 didactic, the aim being to supply short practical recipes to be read at the side 
 of the beck. We commence with a recipe for bleaching cotton stockings: — 
 ioo dozens of stockings are boiled for five to six hours in a lye made of 
 
 4 lbs. of caustic soda, after which they are to be rinsed in cold water. 
 During this time dissolve 25 lbs. of good dry chloride of lime in warm water, 
 and fill a barrel with it. Let the liquor settle, then transfer the clear liquid to a 
 bleaching-tub of stone or wood. The latter cemented is the best and cheapest. 
 The liquid should mark i\° Baume ; but the glass test cannot be relied upon 
 to ascertain the required strength, as the spindle might show £ or i° Baume 
 of other ingredients than the combinations of chlorine, such as carbonate 
 of lime, &c. The strength of the liquor, is, however, very easily and simply 
 ascertained by the experienced workman. The liquor ought to smell strongly 
 of chlorine when held close to the nostrils ; the goods should become con- 
 siderably bleached after twenty-five minutes' immersion ; but if they remain 
 raw coloured more chloride of lime is required. 
 
 The boiled and rinsed stockings are now entered into the bleaching-vat and 
 handled for a few minutes ; then allowed to remain for six or more hours, 
 perhaps over night. If the liquid is made a little warm, say 90 F., the 
 stockings will bleach in two hours, and be ready to be taken out and rinsed. 
 Then pass them into a vat filled with clean water to which 6 lbs. of sulphuric 
 acid has been added. The strength of this sour water can be ascertained by 
 the taste. The stockings ought to lie in this sour for about half an hour, 
 when they are rinsed .again in fresh water. Now they are ready to be scoured 
 in the fulling-mill with warm water and white soap, enough of the latter to 
 make a foam, after which they are rinsed and dried for the market. 
 
 If the stockings require blueing, then add 1 oz. of ultramarine to the soap 
 in a tub large enough to hold about 25 dozens of stockings, or a mill full at a 
 time. The ultramarine and soap must be stirred well ; the stockings entered 
 to get the blue even, and then fulled for about fifteen minutes or more ; then 
 taken out and carefully rinsed. As the ultramarine is not a dye, but only a 
 fine powder, of course too much or uneven rinsing will injure the appearance 
 of the fabric. 
 
 If the goods require stiffening, add J lb. of boiled starch to the soap while 
 scouring. A very fine shade of blueing, and which is fast, is produced by 
 passing the stockings, after they have been bleached, through a bath con- 
 taining the solution of 1 lb. of blue vitriol and 2 ozs. of arsenic; after that, 
 through the soap, as usual, and scoured. 
 
 Caustic soda at once makes soap of the oil or grease in the stockings during 
 boiling, and is therefore superior to soda-ash. It is best made by the dyer 
 himself as follows : — 
 
 Dissolve 25 lbs. of soda in a barrel filled with warm water, to which add 
 
 5 or 6 lbs. of slaked lime. Let the whole settle, and use the clear liquor, 
 which is a solution of caustic soda. A too large quantity of lime is immaterial, 
 as the soda will take up only a certain quantity to make it caustic. The 
 settlings may be leached for future use. 
 
 Bleaching Cotton Stockings Merino Shade. 
 Have the stockings all bleached as described ; then add to the soap in 
 which the stockings are fulled 2 ozs. of turmeric to every mill full of hose. 
 
 E 2 
 
52 
 
 DYEING AND CALICO PRINTING. 
 
 Rinse and dry in the shade, because the colour is very fugitive. The bleached 
 goods might also be coloured after scouring with fustic and alum ; the colour 
 would be more permanent, but the process would require a longer time. Hot 
 bleaching makes the goods appear woolley, and so does a brushing machine 
 when they are dry. 
 
 Bleaching Cotton Stockings with Turkey-Red Tops. 
 Boil ioo dozens with 5 lbs. of soda and 4 lbs. of soap for several hours, 
 then take them out and rinse. They should be now entered in the bleaching- 
 vat, which ought to be moderately strong. Handle the goods well, and let 
 them lie in the liquor for a few hours, or until they are bleached enough ; 
 then take them out, allowing them to remain in the air as short time as 
 possible. They should then be soured for half an hour, linsed, and scoured 
 with soap. Inferior Turkey-red dyed goods need great care in bleaching. 
 
 Bleaching Raw Cotton in Small Quantities. 
 
 If the same process were adopted as for stockings it would be tedious and 
 expensive, but the bleaching of raw cotton on the small scale is easily 
 effected by the following method : — 
 
 Boil the cotton in fresh water, without any lye or soda, only a few minutes, 
 merely to saturate it. Long boiling would injure the fibre for spinning. Then 
 pass the cotton into the bleaching-vat containing chloride of lime in such 
 quantity as the operator may consider necessary. The cotton should be 
 handled for fifteen minutes, then allowed to remain for four or five hours, 
 afterwards being placed upon an inclined board to allow the liquor to drain 
 back. The cotton is now rinsed in small quantities, and to every rinsing add 
 1 lb. of diluted sulphuric acid ; stir the cotton in this sour for a few minutes, 
 then let it off, and give the cotton a few more waters, so as to rinse all the 
 acid away ; then dry. The cotton will be quite white and easy to spin. The 
 expense, inclusive of drying, will amount to about twopence per lb. 
 
 The Continuous Process of Bleaching. 
 By all dyers and bleachers having extensive business the continuous 
 process, sometimes known as the "new," the " Bentley," or "Pendleton" 
 process, is generally adopted, effecting a considerable economy in time and 
 labour. The process was first patented by David Bentley, of Pendleton, in 
 1828, and in principle consists in drawing the goods successively through all 
 the bleaching solutions, the pieces being made continuous with the aid of 
 the sewing machine. The following is a general outline of the operations: — 
 The pieces having been sewn together with the aid of a machine, are arranged 
 in a carefully-constructed rope-like coil, being generally drawn through an 
 aperture of smooth glass or earthenware to impart this form. When the 
 pieces have been singed they are drawn into and boiled in the first kier, con- 
 taining 1 lb. of caustic lime to 14 lbs. of cloth. The kier is constructed to 
 hold about 500 gallons, and the boiling is continued for thirteen hours. The 
 pieces are next washed in the washing machine, and are then passed through 
 a sour of hydrochloric acid at 2 Twaddle. Supposing 3500 lbs. of cloth to 
 be used, it is next bowked in a soda-ash and resin solution containing 170 lbs. 
 of soda-ash to 30 lbs. of resin to 500 gallons of water. This boiling is 
 
BLEACHING. 
 
 53 
 
 continued for sixteen hours, and the goods are again washed. The cloth is next 
 saturated with chemick or a solution of chloride of lime for two hours, the 
 density of the solution being about A° Twaddle, when it is again washed. 
 The continuous length is now boiled in a kier for five hours with ioo lbs. of 
 crystals of carbonate of soda. After washing it is chemicked as before ; 
 then soured in hydrochloric acid of 2£° Twaddle. The cloth is next allowed 
 to drain, is washed until quite clean, squeezed between rollers, finally 
 being dried over steam cylinders or by means of a hydro-extractor. To 
 effect these operations in one continuous process, many improvements have 
 been suggested upon the plan pursued originally by Bentley, but as the 
 principle is undoubtedly due to him, we shall describe the apparatus as it 
 first appears in his patent. 
 
 Fig. 3 is an end view of two calenders, each having two larger rollers, 
 B and B', a smaller driving roller, c, two racks, D and D 1 , placed upon two 
 cisterns, g and g 1 , inside of which are two rollers, e and e 1 , having four 
 square ribs upon each, to shake the goods as they pass through the cisterns. 
 
 Fig. 3. 
 
 At f is a series of rollers, upon which the batches of goods are placed. The 
 calender cheeks are made fast at the feet, at the middle, and to the top of the 
 building, having levers and weights, H, to give pressure to the calender bowls. 
 Near the end walls of the building are two rollers, one of which is shown at 
 a; upon each of these a soft cord is used as a guide for conducting the goods 
 through the machinery and cisterns. The operation is commenced by passing 
 one end of the cord through the rollers b and c, down to cistern g, under 
 roller e, through the most remote division of rack d, and again through 
 calender rollers at b and c, repeating the same, but observing to keep the 
 cord tight, and to approach one division nearer in rack d each revolution until 
 each division is occupied, when the end must pass over c, under and round 
 B 1 , down to and over the guide-roller i 3 , through the nearest division of 
 rack d 1 into cistern g 1 , under roller e 1 , over guide-roller i 2 , and again over 
 roller c, under and round b 1 . This course must be repeated, observing as 
 before to keep the cord tight, and to receive one division of rack d 1 every 
 revolution, until each division of rack d 1 is occupied, when the end must pass. 
 

 ^p 
 
 54 
 
 DYEING AND CALICO PRINTING. 
 
 over from b 1 under i 4 . The cord now forms a sort of spiral worm round and 
 through the machinery and cisterns, beginning at b c, and ending at the top of 
 B 1 to i 4 , the number of revolutions being governed by the number of 
 divisions in the racks d and d 1 , so that if there were fifteen divisions in each 
 rack there would be fifteen revolutions under c, round b, through g, under E, 
 through d, and fifteen revolutions over c, round B 1 , over i 3 , through d 1 and 
 g 1 , under e 1 , over i a , and again over c, passing from the top of b 1 to i 4 ; and 
 by this means, if one end of the goods marked k, and placed upon the series 
 of rollers F, is fastened to the end of the guide cord, the goods will, when the 
 calender is put in motion, be conducted and washed thirty times through the 
 water in the cisterns, and squeezed thirty times through the calenders. As 
 the operation proceeds and the guide-cord passes through the calender, it is 
 wound by hand upon roller a to prevent it from becoming entangled, and to 
 keep it in readiness for the next operation. As soon as the first end of the 
 
 Fig. 
 
 tZ^_ 
 
 r 
 
 \Z7- 
 
 "^Z7- 
 
 <yT1S ;VS ? US >HS FW <t1S .^ /It*. ftS /TTA/Tf^ 
 
 mmmm 
 
 w 
 
 MjWi.H i l l ! II 11 >!!! miikJiII mi in; Jt n iMJRTr 
 
 'i-' ''^ 
 
 -J 
 
 goods arrives at the guide-roller i 4 it is detached from the end of the guide- 
 cord and attached to the guide-cord at the other end, or with the opposite set 
 of calenders. After this, by putting these in motion, the goods are washed 
 and squeezed through its cisterns, supplied with hot and strong lime-lye, and 
 the goods passing over guide-roller i 9 are conveyed over other guide-rollers to 
 be placed for the purpose, and taken down by some person or by proper 
 machinery into one of the boiling vessels, where they are suffered to remain 
 while the lime-boiling is effected. 
 
 The goods are saturated with the solutions by the aid of an apparatus 
 shown in Fig. 4, being designed to supply continuous rapid motion and 
 pressure to obviate the danger of rotting from still soaking, b b b are the 
 washing rollers ; c c c are the gear or speed rollers ; e e e are rollers 
 immersed in as many divisions of the cistern g, Fig. 3. The washing rollers, 
 b b b (Fig. 4), are allowed to rise and fall upon the rollers ccc, according to 
 the pressure exerted by the weights h h h. The goods having been steeped 
 
BLEACHING. 
 
 55 
 
 are placed in batches at f, and passing under the immersing rollers, e, and 
 the divisions of the cistern g, between the speed or gear rollers, c, and the 
 washing rollers, b, are taken down straight and open into one of the vessels, and 
 are then boiled by steam, which is succeeded by repeated washings alternately 
 in water and bleaching liquors, until they are sufficiently bleached as before 
 described. 
 
 Figs. 5 and 6 show the elevation and ground plan of a bleach-house and 
 machinery capable of working 8oo pieces of 4 lbs. cloth per day, with the 
 labour of one man and three boys, from four to six o'clock, d represents two 
 lengths of cloth of 400 pieces each, passing through the washing machine, g, 
 and from thence over the winch, w, into the kier, c, where they are boiled in 
 
 Fig. 5. 
 
 ^ 
 
 lime for twelve hours. They are then withdrawn by the same washing 
 machine, g, washed, and passed into the second kier, b, where they are boiled 
 for twelve hours in soda-ash and resin. They are again withdrawn by the 
 same machine, g, washed, squeezed (see plan at u), and passed over winch, e, 
 and piled at h. They are then withdrawn from the pile, h, and threaded 
 the sour machine, e, soured, passed over winch e l , and piled at k, where the 
 cloth remains for three hours. It is then squeezed at u, and submitted to the 
 washing machine, g, whence it is delivered into the third kier, a, boiled for 
 six hours, again washed at g, and squeezed. It is then passed through the 
 chemick, allowed to remain in pile for one hour ; again soured, squeezed, and 
 washed at g, again squeezed at/, and dried over the cylinders p. 
 
* 
 
 s^ 
 
 
 56 
 
 DYEING AND CALICO PRINTING. 
 
 The most important modifications of the continuous process of bleaching 
 recently are those patented by Mr. Barlow in 1866. This inventor combines 
 in one machine not only the various apparatus required for bleaching, but the 
 operations successively of dyeing, printing, and sizing, subdividing the troughs 
 or cisterns containing the mordants and the dyes by cross partitions, so that the 
 
 Fig. 6. 
 
 
 
 
 
 
 
 
 
 u 
 
 1 i 
 
 
 
 
 □ 
 
 
 
 1 ! 
 
 
 several threads passing through the machine at the same time may be dyed 
 in different colours or partly left uncoloured. 
 
 These machines are, however, not adapted to the bleaching of linen. 
 Linen does not possess the elasticity of cotton, and the strain would either 
 pull the cloth narrow or tear it. 
 
 Bleaching with other Chemical Agents. 
 Several processes of bleaching with th« aid ofchlorochromic acid, chromates, 
 chlorates, manganates, and sulphites have been from time to time introduced, 
 but the operations have not been sufficiently successful or the use so 
 extensive as to call for detailed description. 
 
(57) 
 
 CHAPTER V. 
 
 LINEN FIBRE. 
 
 '"pHIS fibre is obtained from the stem of an animal plant called Linum 
 usitatissimum, belonging to the natural order of the Linnee. Of what 
 country it is a native is uncertain ; but from its having been used by the 
 Egyptians for mummy cloths, and that it is still found in those parts of 
 Egypt which are inundated by the Nile, it is conjectured that it must 
 originally have come to us from that country. 
 
 Three distinct varieties of flax are grown in Europe, viz., the cold or large 
 flax, which has thin, tall stems, and yields a very fine long fibre, in great 
 demand for the beautiful fabrics known as " Flemish Batist." This flax 
 ripens earlier than the two other varieties. 
 
 The second variety is the hot or small flax, which yields a large quantity of 
 seed (linseed), but its fibres are coarse and short. 
 
 The third variety, termed middle-sized flax, is the one most largely 
 cultivated, and, as regards the fibre, most generally used. 
 
 Flax is grown in great abundance in Italy, Russia, Saxony, Holland, 
 Belgium, and the northern parts of France. The fibre is separated from the 
 plant in the following manner : — 
 
 The flax after being cut is allowed to remain in the field till it is dry. The 
 seed is then beaten out, after which the flax undergoes a process termed 
 retting, producing a peculiar fermentation, whereby the glutinous matters are 
 destroyed, and the woody portions of the stem disintegrated ; these portions 
 being afterwards separated from the fibre by a mechanical process. Various 
 propositions have been made at different times to substitute the use of 
 chemicals for the retting process, which consists in steeping the plant in 
 water ; but it appears that the latter plan succeeds best. The water must be 
 employed at a temperature of g6'8° F. (36 C.) The plants are placed vertically 
 in tanks, so constructed as to admit of the water being renewed from time to 
 time. 
 
 Viewed through the microscope, flax fibre exhibits hollow cylindrical tubes, 
 open at both ends ; the average diameter of these tubes is from 4 ' 4 to J s m.m.; 
 their surface is smooth ; septa or knots appear at intervals, but they are not 
 furnished with hairy appendices, as is the case with hemp. 
 
 Bleaching Linen. 
 
 The flax fibre is surrounded by a somewhat thick incrustating matter 
 of a yellowish grey colour, and consequently it is far more difficult to 
 
■ii 
 
 58 
 
 DYEING AND CALICO PRINTING. 
 
 bleach linen than cotton fabrics. Flax fibre being more susceptible of injury 
 than cotton fibre, a more tedious bleaching process is necessary. It is con- 
 ducted in the following manner: — The linen, instead of being steeped in hot 
 or cold alkaline lyes, is first macerated in an infusion of malt at 149 F. (65 C), 
 after which mixtures of carbonated and caustic alkalies or resin-soap are 
 employed at temperatures not exceeding 140 F. (6o° C.) ; these are repeated 
 after every washing and maceration. The linen is next exposed to the air on 
 grass fields, and after the alkaline washings have been frequently repeated a 
 weak solution of bleaching-powder is employed, followed by a sour-bath. It is 
 impossible for linen to be thoroughly well bleached without frequent exposure 
 to the air, and the expense attending these exposures partly accounts for the 
 high price paid for linen as compared with cotton. 
 
 Such is the old method of bleaching linen, but later methods have been 
 introduced in which the time of exposure on the grass, or " crofting," as it is 
 termed, is much shortened. Dr. Ure very fully describes one of these 
 processes as practised by an extensive bleacher in Scotland and Ireland, as 
 follows : — 
 
 1. Wash. 
 
 2. Boil in lime-water ten or twelve hours. 
 
 3. Sour in muriatic acid, of 2° Twaddle, for three, four, or five hours. 
 
 4. Wash well. 
 
 5. Boil with resin and soda-ash twelve hours. 
 
 6. Turn the goods, so that those at the top shall be at the bottom, and boil 
 again as at No. 5. 
 
 7. Wash well. 
 
 8. Chemick at £° Twaddle, or 1002-5 four hours. 
 g. Sour, at 2 Twaddle, ioio*o specific gravity. 
 
 10. Wash. 
 
 ii. Boil in soda-ash ten hours. 
 
 12. Chemick again. 
 
 13. Wash and dry. 
 
 Other processes are adopted for sheetings, but, for printing, that quoted may 
 be considered a fair example. By this process a fortnight is consumed in 
 bleaching the goods. The continental processes are even still more tedious, 
 occupying generally a period of six weeks. 
 
 White Bleaching Linen Yarn. 
 On the small scale the yarn may be boiled in a lye of soda-ash, or better, 
 caustic soda, for about five or six hours ; then taken out and rinsed ; passed 
 through a bath of chemick, when it will assume an egg-yellow shade. Then 
 it must be rinsed, and crofted, or spread on the grass exposed to the sunlight ; 
 and if it is often wetted with water and turned it will become perfectly white 
 in a few days. 
 
 Colouring Linen Yarn for Carpets on the Small Scale. 
 
 Coarse yarn is largely employed in the manufacture of special classes of 
 carpets, and we append to the consideration of linen and its modes of 
 bleaching some practical formulae for the colouring of the yarn. 
 
 The yarn for blue, red, yellow, green, lilac, and aniline colours ought to 
 
COLOURING LINEN YARN FOR CARPETS. 
 
 59 
 
 be bleached by taking it first through a warm bath containing a weak solution 
 of chloride of lime, and then rinsing in fresh water. The yarn will still have 
 a yellow appearance, but it will be bleached enough for the foregoing colours. 
 
 Yellow. 
 
 If there should be a variety of colours to prepare, it is better to commence 
 with the yellow. 
 
 To 50 lbs. of yarn, bleached, boil for fifteen minutes — 
 
 1 lb. of flavine, 
 5 lbs. of alum, 
 
 4 lbs. of muriate of tin,* 
 
 2 ozs. of tin crystals. 
 
 Cool the dye to 170 F. ; enter the yarn on poles, and turn it swiftly a few 
 times ; then slowly for twenty minutes. Take the yarn out, rinse in fresh 
 water, and dry. 
 
 Green. 
 
 To 50 lbs. of linen yarn add to the above yellow dye — 
 
 5 lbs. of alum, 
 
 2 lbs. of muriate of tin, 
 2 ozs. of tin crystals, 
 
 4 ozs. of flavine. 
 
 The dye should be thoroughly mixed by boiling for ten minutes. When 
 cool the bleached yarn is to be entered on poles, handled quickly at first, then 
 slowly for twenty minutes, taken out and rinsed. 
 
 Now prepare a suitable tub with cold water, to which add a solution of 
 1 lb. of extract of indigo, and 6 lbs. of alum. The yellow rinsed yarn is now 
 passed into this blue-bath, and turned quickly for a few minutes; then 
 occasionally for a few hours, or until even, when it will be ready to be 
 switched and dried, without rinsing. 
 
 Red. 
 
 To 50 lbs. of bleached yarn boil in the above yellow kettle for a few minutes — 
 
 5 lbs. of sumach, 
 
 1 lb. of flavine, 
 5 lbs. of alum, 
 
 2 ozs. of tin crystals. 
 
 Then cool the kettle to 180 F.; enter the yarn, and handle it as usual for 
 about fifteen minutes ; then take it out. It is not necessary to rinse it ; but 
 
 * Muriate of tin, otherwise scarlet spirit, as it is termed by dyers, is used as a mordant 
 (spirit being a technical term for mordanl), and the practical recipe for its preparation is as 
 follows : — 
 
 16 lbs. of hydrochloric acid (22° B.), 
 
 1 lb. of feathered tin, 
 
 2 lbs. of water. 
 
 The acid is poured into a stone pot, the tin at once added, and dissolved. 
 
 Tin Crystals are similarly prepared, only a larger quantity of feathered tin is added, the 
 pot being placed on a sand-bath to facilitate solution, and the solution evaporated to 
 crystallisation. 
 
6o 
 
 DYEING AND CALICO PRINTING. 
 
 take now one pole after another through a small tub containing perhaps 
 6 pails of water and 3 lbs. of nitrate of tin.* Add a little nitrate of tin for 
 every new pole taken through, and handle each pole in the mordant for one 
 and a half minutes. It is cheaper to have a small tub for this bath, as the 
 yarn can be then strongly mordanted, which is necessary to obtain a good 
 red. Place a board on the top of the side of the tub, so that the liquid will 
 run back from the yarn laid upon the board to drain. Next prepare a kettle 
 with warm water at 125 F., and add the infusion of 15 lbs. of common 
 peachwood.f While stirring, enter the prepared yellow yarn, turning it 
 quickly two or three times, and then slower for twenty minutes, when it will 
 be of a fine red. The red can still be improved by adding 2 lbs. of whiting 
 to neutralise the acid. The acid must be rinsed from the yarn before the 
 latter is dried. 
 
 Orange, with Madder. 
 To 50 lbs. of yarn, bleached, add to the yellow kettle above — 
 
 1 lb. of flavine, 
 5 lbs. of alum, 
 
 2 lbs. of muriate of tin, 
 2 ozs. of tin crystals, 
 
 5 lbs. of madder. 
 This kettle must be boiled for ten minutes, and then cooled to 170 9 F. The 
 yarn is now to be entered, turning it quickly a few times to obtain evenness, 
 then slowly for about fifteen minutes. It can be then removed, rinsed, and 
 dried. 
 
 Orange, with Annatto. 
 
 This orange is brighter on linen than the one just described with madder, 
 but the colour is not so fast. 
 
 For 50 lbs. of bleached yarn. Boil 1 lb. of annatto with 4 lbs. of soda-ash, 
 pouring the whole into a kettle of hot water of 160 F. Enter the yarn and 
 handle for fifteen minutes, rinse, and dry. 
 
 Brown and Maroon. 
 Pass 50 lbs. of dry yarn, unbleached, through the yellow kettle, handling for 
 fifteen minutes. After removal mordant the yarn with nitrate of tin as for 
 red ; next enter it into a kettle containing the liquor of 10 lbs. of peachwood 
 with 10 lbs. of logwood, handling for twenty minutes ; rinse and dry. For 
 maroon more peachwood and less logwood will be required. 
 
 Crimson. 
 For 50 lbs. of bleached yarn. Take the yarn through the liquor of 10 lbs. 
 of boiled sumach ; next through the cold nitrate of tin mordant, thoroughly 
 
 * Nitrate of tin may be prepared thus :— To 5 lbs. of hydrochloric acid (22 B.), 10 lbs. of 
 nitric acid (36 B.), 5 lbs. of water ; add 1 lb. of feathered tin in very small quantities at a 
 time to the acid so as not to overheat it. 
 
 + Peachwood liquor is sometimes termed, chiefly in America, hypernic. This term is 
 derived from Nicaragua (Nicaragua wood), whence " Nicric," a superior quality of liquor 
 from the same wood being termed " hyper-nic' 
 
COLOURING LINEN YARN FOR CARPETS. 61 
 
 impregnating the yarn. Then pass it into a warm beck (140° F.) containing 
 the boiled liquor of 15 lbs. of peachvvood. After twenty minutes rinse and dry. 
 
 Pensee Brown. 
 For 50 lbs. of dried yarn. To a kettle of water at 140 F. add — 
 5 lbs. of alum, 
 
 10 pails of logwood liquor (2 lbs. to the pail), 
 5 lbs. of nitrate of tin. 
 The yarn must be handled for twenty minutes, rinsed, and dried. To render 
 the colour more even the yarn may be taken through the alum and logwood 
 liquor first, then removed, the nitrate of tin added, and the yarn re-entered 
 and finished. 
 
 Magenta. 
 
 For 50 lbs. of well-rinsed yarn. Dissolve i£ ozs. of magenta crystals in 
 hot water, and add the solution to a warm beck at about 150 F. The yarn 
 should be entered and handled thoroughly for twenty minutes, the beck being 
 well stirred. Switch and dry without rinsing. 
 
 Aniline Purple. 
 For 50 lbs. of well-rinsed bleached yarn. Dissolve 2 ozs. of aniline 
 purple in 1 pint of hot alcohol, and add the alcoholic solution to a bath of 
 warm water at 140 F., next adding 4 lbs. of acetic acid. Handle the yarn in 
 this beck until the colour has become even ; rinse and dry. 
 
 Aniline Blue. 
 For 50 lbs. of bleached yarn. Dissolve 4 ozs. of aniline blue powder in 
 
 1 pint of hot alcohol, adding the solution to a kettle of warm water at 140 F., 
 together with the solution of 3 lbs. of Glauber salts, and 2 lbs. of acetic acid. 
 The kettle must be heated to nearly the boiling-point while handling the 
 yarn. After twenty minutes remove, rinse, and dry. 
 
 Prussian Blue. 
 
 For 50 lbs. of bleached yarn. A beck, slightly warm, must be prepared with 
 3 lbs. of nitrate of iron,* to which should be added 2 lbs. of muriate of tin. 
 The yarn having been turned five times in this iron bath, should be removed 
 and passed through a second bath, consisting of the solution of 2 lbs. of 
 yellow prussiate of potash with 1 lb. of sulphuric acid. After draining for a 
 few minutes, pass the yarn again through the iron bath. If the colour be 
 desired darker, handle once more through the prussiate bath. Then rinse 
 well, and dry. 
 
 Lilac. 
 
 For 50 lbs. of bleached yarn. Have in readiness 2 pails of a warm infusion 
 of logwood, to which add 4 lbs. of alum and 2 lbs. of muriate of tin. Handle 
 the yarn for twenty minutes, remove, and rinse. 
 
 * Nitrate of iron may be prepared as follows: — To 5 lbs. of water in a stone vessel add 
 
 2 lbs. of hydrochloric acid (22 B.), and 10 lbs. of nitric acid (36 B.) In this acid solution 
 wrought-iron chips are dissolved, care being taken not to add iron in excess. When sufficient 
 iron has been dissolved, or the acid is nearly saturated, 5 lbs. of copperas are to be added. 
 When the copperas is dissolved the mordant is ready for use. 
 
62 
 
 DYEING AND CALICO PRINTING. 
 
 Bismarck. 
 For 50 lbs. of bleached yarn. Form a beck with 5 lbs. of boiled madder, to 
 which add a solution of 5 lbs. of alum, heating the' beck to 150 F. Handle 
 the yarn for five turns ; then add to the beck 2 lbs. of muriate of tin ; handle 
 for fifteen minutes, rinse, and dry. 
 
 Slate. 
 
 For 50 lbs. of bleached yarn. Pass the yarn through a warm bath, con- 
 taining 5 lbs. of boiled sumach and 1 pail of logwood liquor, giving the yarn 
 six turns. Then remove the yarn, and pass it through a cold solution of 
 2 lbs. of copperas and £ lb. of blue vitriol. After twenty minutes rinse and 
 dry. 
 
 Cutch Brown (fast). 
 
 Take 50 lbs. of dry yarn through a hot beck containing the solution of 
 10 lbs of cutch ; or the yarn may lie in the beck over night. Then remove 
 the yarn and handle it through a hot solution of bichromate of potash. Rinse 
 and dry. 
 
 Black. 
 
 For 50 lbs. of yarn. Have in readiness a kettle containing 10 pails of 
 logwood liquor, to which add 2 lbs. of blue vitriol and 2 lbs. of soda-ash. 
 When these are dissolved, cool the kettle to 180 F., enter the dry yarn, and 
 handle it for twenty minutes. Then remove, rinse, and diy. 
 
 Another Black, a Fast Colour. 
 For 50 lbs. of dry yarn. Soak the yarn overnight in a warm solution of 
 15 lbs. of sumach. The next morning remove the yarn, and pass it through 
 a warm solution of 5 lbs. of copperas, 1 lb. of blue vitriol, and 2 lbs. of 
 whiting. Then handle it through a cold weak lye of lime-water ; rinse the 
 yarn, and again pass it through the sumach bath, to which has been added 
 6 pails of logwood liquor and 1 lb. of boiled starch. The latter will pre- 
 cipitate all the dye-stuff upon the yarn, and a good black, perfectly fast, will 
 be obtained. 
 
(63) 
 
 CHAPTER VI. 
 
 HEMP, CHINESE GRASS, JUTE, AND OTHER FIBRES. 
 
 T TEMP is the fibre of an annual plant known as Cannabis safiva, originally 
 ■^ ■*• found in Asia. It has, however, been cultivated in Europe for many 
 centuries. This plant attains a height of from 1-3 to 26 metres, and, as in 
 flax, the fibre runs through the entire length of the stem. It is both separated 
 from the plant and bleached in a similar manner to flax, but the bleaching is 
 more difficult on account of the greater quantity of incrustating matter that 
 surrounds the fibre. Seen through the microscope, the hempen fibres exhibit 
 hollow cylindrical tubes, quite smooth externally, and provided at regular 
 intervals with septa or knots, surrounded by small hairy appendices. Hemp 
 fibre averages fo to ^ of a millimetre in diameter. It is chiefly employed 
 in making rope, twine, and sail-cloth, and consequently is rarely dyed or 
 bleached. 
 
 The other fibrous materials known to us may be divided into three kinds, 
 viz., those obtained from the stems of plants, those from the leaves, and 
 those from the nutshell. 
 
 To the first division belongs the so-called Chinese grass, the fibre of a plant 
 included in the natural order of the Urticacece, more particularly the Boehmeria 
 nivea, cultivated to some extent in China. The fibre when woven to tissue 
 constitutes the China grass cloth, but it is not used to any great extent either 
 in Europe or Asia. 
 
 Ramee hemp is made from the fibres of the Urtica utilis, a native of Borneo, 
 Sumatra, Java, and some of the smaller Sunda Islands. These fibres average 
 about i*5 to 2 - 2 metres in length. They are naturally of a bright yellow- 
 white colour, readily bleached to a very perfect white, but are not much used 
 on account of an inherent stiffness, which, as far as present experience goes, 
 cannot be removed. The natives make cordage of the fibre, but it is of inferior 
 strength, and does not well resist the action of sea-water. 
 
 Rhea hemp from the Rhea tcnacissima, East Indies, is used very little even 
 by the natives. 
 
 Jute, the fibre of the Corckorus olitorius, together with the other species of 
 the same family, is, with the exception of hemp, used more largely than any 
 of the fibres referred to ; it is not, however, suitable for making cordage, as it 
 breaks too readily, and rots under water, but it is extensively used for sail and 
 other coarse cloth. Its finer fibres are, it is stated, woven into such fabrics 
 as poplins and mixed reps. Jute is also used by hatters, as it will take a 
 good black dye. 
 
64 
 
 DYEING AND CALICO PRINTING. 
 
 Bombay hemp is the fibre derived from the Hibiscus cannabinus ; its use is, 
 however, very limited. 
 
 Amongst the fibres obtained from leaves those chiefly in use are : — New 
 Zealand flax, the fibre from the Phormium tenax. This fibre is very strong, 
 especially in its crude state, but it is very difficult to bleach. The plant 
 could very well be cultivated in Europe, but as the process by which the 
 fibre is obtained is a tedious one, and its natural colour a light cinnamon- 
 brown, it is not favourably received. A gummy juice is obtained from this 
 plant, which is beginning to be used for rendering envelopes adhesive, as 
 paper fastened by it cannot be opened either by damping or steaming. 
 
 Several species of the Agave tribe yield fibres which are sometimes used, 
 but they are not well known in Europe. 
 
 Manilla hemp is the fibre derived from the Musa tcxtilis, and other species 
 of the same family. This fibre is brought to Europe, and, mixed with hemp, 
 is made into rope, twine, sacking, &c. The leaves of the Bromelia ananas 
 (the pine-apple plant) contain fibres of great comparative whiteness, but even 
 in such countries as Mexico, where the pine-apple is so plentiful as occasionally 
 to be used as fuel, the extraction of the fibre from the leaves is not attempted 
 to any great extent, the difficulty of getting rid of the concomitant vegetable 
 matter being too great, especially as cotton can be grown there, and in most 
 of the countries where the various fibres alluded to are produced. 
 
 Coir, or cocoa-nut fibre, is obtained from the exterior shell (pericarpium) of 
 the fruit of the cocoa-nut palm. It is used in its unbleached natural state for 
 making matting, &c. 
 
 Very little is known about the action of dyes on these fibres ; some of them 
 are never dyed; even linen (flax fibre), which after bleaching is pure cellulose, 
 does not take some colours so well as cotton. 
 
(65) 
 
 CHAPTER VII. 
 
 THE MEANS OF DISTINGUISHING VEGETABLE FIBRES FROM EACH OTHER. 
 
 A S the fibres when thoroughly bleached are almost pure cellulose, it is 
 evident that chemical tests cannot be applied for the purpose of dis- 
 tinguishing one kind from another; but as the incrustating matter can never, 
 on a large scale, be entirely removed, it is possible by chemical tests to 
 distinguish between flax and cotton, the two principal vegetable fibres. 
 
 Messrs. Bcettger and Kuhlmann employ for this purpose the yellow-orange 
 colour caused by the action of caustic alkalies on these fibres. M. Bcettger 
 immerses the materials to be tested in a boiling solution of equal parts by 
 weight of water and caustic potassa ; they are allowed to remain in this 
 solution for about a minute, when they are removed and placed between sheets 
 of blotting or filtering paper, and the excess of liquid expressed. Flax fibre 
 or linen assumes a dark yellow colour, while cotton either remains white or 
 becomes a very bright yellow. According to M. Kuhlmann, raw cotton, when 
 placed in a very concentrated but cold solution of caustic potassa, becomes 
 bright grey, while flax under the same conditions assumes an orange -yellow 
 colour, which is probably due to^the presence of pectic substances, pectine or 
 pectic acid. 
 
 M. Kindt states that strong sulphuric acid at the ordinary temperature 
 destroys cotton far more rapidly than it does hemp or flax. 
 
 When cotton and flax or their tissues are immersed in oil and strongly 
 pressed in order to remove the excess of the liquid, the cotton remains opaque, 
 while the flax becomes transparent. 
 
 New Zealand flax may be distinguished from ordinary flax or hemp by the 
 fact that on being immersed in nitric acid of 36 Baume containing nitrous 
 acid in solution, it assumes a red colour, or, if it is first immersed in strong 
 chlorine water and then in ammonia, a reddish tint is imparted, which is not 
 the case with hemp or flax grown in this country. The best means, however, 
 of distinguishing the different fibres is to examine their minute structure by 
 the aid of the microscope ; in this way reliable results are obtained. 
 
(66) 
 
 CHAPTER VIII. 
 
 VEGETABLE THICKENINGS. 
 
 'T^HE principal substances used as thickeners are starch, fecula, flour, 
 various kinds of disintegrated starch, such as roasted starch, lei'ocome, 
 dextrine, gommeline, gomma, the gum produced by cherry and plum trees, the 
 genuine gums, such as arabic, Senegal, tragacanth, Bassora gum, salep, sago, 
 linseed, and carragheea. All these substances are, in chemical parlance, 
 carbo-hydrates; their formula is typified by that of cellulose, with which they 
 have many properties in common. 
 
 Amylaceous Matters — Starch, Fecula, C6H I0 O 5 , or C 12 H 20 O Io . 
 
 Amylum, that is, grain which needs no grinding, is a very common constituent 
 of the entire vegetable kingdom. It exhibits an organised substance of globular 
 shape, the size of the globules varying with the species of the plant from 
 which it is produced. Every grain is composed of concentric layers of 
 different densities, superimposed one upon another. In the centre a small 
 nucleus may be seen by the aid of a microscope, which serves as a common 
 centre for the different layers. The peculiar construdion of the starch 
 globules is seen to greater advantage after the substance has been heated to 
 392 F. (200 C.) and then swollen by immersion in water. The shape of 
 these globules is polyangular. Their size varies considerably ; expressed in 
 thousandths of a millimetre it is as follows: — Ccinna gigantea, ovoid shaped, 
 175 diameter; Sulanum tuberosum (potato), ovoid, 183 diameter; beans 
 (cotyledons), oblong, 75 diameter; wheat, and similar kinds of grain, spherical, 
 45 to 50 diameter; sago, a flattened ovoid, 35 diameter; for Zea Mais (Indian 
 corn) a rounded polyhedron, 24 diameter ; the seed of Chenopodium quinoa, 
 globular, 2 diameter. 
 
 The amylaceous matter is enclosed in ceils while in the living plant, and 
 is found in abundance, together with more or less nitrogenous matter, in the 
 trunks of many kinds of palm trees, in the perispermium and cotyledons of 
 seeds, more especially beans, peas, and the various kinds of grain; in the 
 roots, tubers, and bulbs of plants, as, for instance, in carrots, rhubarb, liquorice, 
 manioc, potatoes, florentine iris, bryonia, tulips, &c; in some fruits, as acorns, 
 chestnuts, buckwheat, &c. ; it is also found in many kinds of lichens. 
 
 Starch is used only in the pure state, as obtained from wheat, rice, potatoes, 
 chestnuts, Indian corn, and the various kinds of arrow-root, with all which 
 vegetable substances it is intimately associated. The methods by which 
 starch is prepared are based upon its insolubility in cold water, together with 
 its comparatively high specific gravity, and its resistance to the a&ion both 
 of weak acids and alkalies, and also to putrefactive fermentation at the 
 
VEGETABLE THICKENINGS. 
 
 6 7 
 
 ordinary temperature of the air. The manufaifhire of starch may therefore be 
 considered as a process of mechanical separation, aided by weak solvents of 
 an acid or alkaline nature. It is very hygroscopic, and may retain even as 
 much as 45 per cent of water (the so-called green starch) ; but in dry starch 
 the quantity of hygroscopic water generally varies from 3 to 16 per cent. In 
 a perfectly dry and pulverulent state starch exhibits a very mobile powder, 
 devoid of smell, taste, and colour. It is, as far as any practical purposes are 
 concerned, insoluble in cold water; but some chemists and botanists aver 
 that when starch is rubbed for some time in a mortar with very sharp sand 
 and cold water, and then filtered, a clear solution is obtained, which is 
 coloured blue on the addition of tincture of iodine, and is precipitated by 
 alcohol and subacetate of lead. In this case every granule of starch should 
 consist of an insoluble and a soluble portion, both isomeric as regards their 
 chemical constitution. This view is strongly supported by the experiments 
 of M. Bechamp, who has succeeded in effecting a molecular transformation of 
 starch, whereby it is made completely soluble, while it retains the property of 
 becoming blue on the addition of iodine. This transformation is effected — 
 (1) By heating starch and monohydrated acetic acid to 212* F. (100° C.) ; (2) By 
 acting upon starch with ordinary acetic acid, and with concentrated sulphuric 
 and nitric acids; this operation requires great care; (3) By reducing xyloidine 
 or nitramadine by means of chloride of iron. This intermediate state being 
 the first stage in the conversion of starch into dextrine, by careful manage- 
 ment this so-called soluble modification of starch may be obtained in all cases 
 where its conversion into dextrine takes place. By polarised light soluble 
 starch exhibits a very marked right-handed rotation of the ray. When starch 
 is made into gum (dextrine) by roasting, and this gum viewed under the 
 microscope with a power of about 300 diameters, after having been moistened 
 with alcohol, the granules remain perfect, the hilum only appearing a little 
 more marked ; but when to the dry gum water is added the granule cracks at 
 the hilum, and the dextrine may be seen oozing out rapidly into the water. 
 The empty starch envelopes may then be seen floating about, very light, 
 retaining the general appearance of the original granule, but with a large 
 aperture with ragged edges where the dextrine has escaped. These envelopes 
 give no colours when viewed with polarised light. The action of boiling water 
 upon starch is simply a disintegration, not a solution, as is proved by the 
 opalescence of the liquid after the addition of a quantity of boiling water, 
 and also by the fact that, on being frozen and again becoming fluid, the whole 
 of the starch is precipitated, and the supernatant liquor on being carefully 
 decanted does not become blue when a solution of iodine is added. A most 
 interesting phenomenon is the conversion of starch into dextrine and sugar 
 under the agency of certain bodies, which, according to Berzelius, appear to 
 act catalytically; that is to say, they induce a molecular conversion, and also, 
 as regards the sugar, the taking up of a molecule of water or hydratation at 
 the same time. Dextrine has exactly the same composition as starch, while 
 glucose differs from it by containing another atom of water. Starch is con- 
 verted into either dextrine or glucose by the following reactions :— (1) By the 
 action of pure water at a temperature of 302 F. (150 C), which if sufficiently 
 prolonged produces glucose ; (2) A dry heat of 392° F. (200" C.) converts 
 starch into dextrine only; (3) When to boiling water two or three hundred 
 parts of its weight of sulphuric, hydrochloric, or any other strong mineral 
 
 f 2 
 
68 
 
 DYEING AND CALICO PRINTING. 
 
 acid is added, and starch (not green starch) previously made into a paste with 
 water is poured into this liquid, which must be kept boiling, the starch is first 
 converted into dextrine, and afterwards into glucose; (4) The peculiarly- 
 modified nitrogenous principle met with in malted barley, generally called 
 diastase (though Professor Mulder proved some years ago in his excellent work 
 on Beer that diastase individually does not exist at all, and that the incipient 
 germination of barley or any other grain has the effect of greatly modifying 
 the composition and action of the protein compounds met with in grain) has 
 the power of converting starch into dextrine and glucose at a temperature not 
 exceeding 167 F. (75° C), and to act thus even in relatively small quantity, 
 since one part of the nitrogenous principle readily converts a thousand parts 
 of dry starch into dextrine, provided sufficient water be present ; saliva, 
 pancreatic juice, bile, and intestinal mucus of men and animals act in a similar 
 manner, and are very rapid in their action. Iodine in free state gives to starch 
 paste a beautiful deep blue colour, which disappears on the application of 
 heat, but the action of this well-known reagent is either entirely or in part 
 prevented by the presence of some substances, among which, according to 
 Goppelsroeder, are many soluble sulphates. If, when dry starch and strong 
 sulphuric acid are mixed at the ordinary temperature of the air, an amylo- 
 sulpho-acid is formed, at a higher temperature the starch is decomposed and 
 becomes black ; it is converted into xyloi'dine at the ordinary temperature by 
 the action of very strong nitric acid, and, at a higher temperature, into oxalic 
 acid. Starch-paste, when exposed to the action of air, is gradually converted 
 into lactic acid. Schweitzer's reagent does not affect starch. When of 
 good quality starch contains but little ash, for the incombustible matter that 
 may be present being only that which was found as solid residue after the 
 evaporation of water, is, therefore, attributable to the water employed in the 
 manufacture of starch. It sometimes happens that starch is purposely 
 adulterated with gypsum, sulphate of baryta, or- prepared chalk, but such 
 frauds are readily detected by incineration. Starch (fecula) is very largely 
 used, especially in the dressing of goods ; it is applied either with or without 
 dextrine to thicken colours for printing ; sago, wheaten flour, wheaten starch, 
 farina, and salep are all thickeners of the same class. 
 
 Dextrine. 
 We have already alluded to the method by which dextrine is manufactured, 
 but it is necessary to mention here that since the colour of what is now called 
 calcined farina was, in many instances, an objection to its being used in calico 
 printing, it was very desirable to find a process for its conversion at so low a 
 temperature as to leave the converted farina nearly colourless. This was first 
 effected in 1838 by M. Payen, who found that by adding 400 parts of dry 
 farina to 1 part of nitric acid at a specific gravity of 1-4, diluted with sufficient 
 water to form with the farina a hard paste, this being dried slowly and heated 
 in a close chamber for twenty hours at a temperature of 392 F. (200 C), a 
 nearly white farina was obtained. It is interesting to observe how so small 
 a quantity as a few thousandths of acid can effect this great molecular change. 
 Since that time many processes have been devised to attain the same end ; 
 such, for instance, as the employment of lactic acid by Mr. E. Hunt, of 
 oxalic and tartaric acids by others, and a process by Mr. Charles O'Neill, which 
 
GUMS. 
 
 69 
 
 is valuable, as it enables him to convert insoluble into soluble farina or 
 dextrine without any change of colour. This he effects by subjecting starch, 
 farina, and other amylaceous substances to the chemical action of hydrochloric 
 or some other acid gas or vapour in a cylinder, the exterior of which is 
 surrounded by an atmosphere of steam. This process cannot be said to have 
 materially extended the employment of soluble farina as a substitute for gum- 
 arabic, as perfectly soluble white dextrine is easily made on the large scale by 
 Payen's process without needing the expensive apparatus used by O'Neill. 
 
 Calico printing, as at present developed, having assumed such extraordinary 
 proportions, thousands of tons of soluble materials for thickening the various 
 mordants and colours are required, and a great variety of this class of artificial 
 gums are prepared to meet the requirements. Thus, in addition to farina, 
 sago, rice, slimes, and wheaten starch are used. The latter substance^when 
 heated generally bears the name of British gum, which differs from calcined 
 farina in being soluble in boiling water only. Pure dextrine exhibits the 
 following properties : — In the dry state it is as white as powdered gum arabic ; 
 it has a slightly sweet taste ; it is soluble in water in all proportions, yielding, 
 according to the proportion of water present, a more or less viscous solution ; 
 insoluble in alcohol, by which it is precipitated from its aqueous solution as a 
 flocculent mass; it gives a strong right-handed rotation to polarised light, hence 
 its name. Nitric acid and heat convert it into oxalic acid, while the native gums 
 are chiefly converted thereby into mucic acid. Solution of neutral acetate of 
 lead does not precipitate a solution of dextrine unless ammonia be added, but 
 it is precipitated by subacetate of lead ; it is also precipitated by chloride of 
 tin, but not by solutions of salts of peroxide of iron. Solutions of iodine 
 impart no colour to dextrine. A hot alkaline solution of oxide of copper is 
 reduced by dextrine, but not by native gums. Commercially, it is distinguished 
 as calcined farina, starch heated to 392° F. (200 C), lei'ocome, roasted wheaten 
 starch, gomma, gommine, and gommeline, all of which are dextrine, more or 
 less pure, and varying in colour, and are prepared by the action of acids and 
 heat upon starch, as already described. 
 
 It should be borne in mind that starch and wheaten flour, with all the 
 substances derived from them or manufactured with them, exert a reducing 
 action, preventing oxidation of the colours. Colours mixed with dextrine do 
 not keep so well as those mixed with gum. 
 
 Gums. 
 
 Four kinds are chiefly used — (1) Soluble gums (arabic, Senegal, and 
 salabreda) ; (2) Gum tragacanth ; (3) Bassora gum ; (4) Inland gum (the 
 gum from cherry, plum, and other stone fruits). Only the first two of these 
 kinds are used as thickeners. 
 
 Gums Soluble in Water belonging to the species of Arabic Gums. 
 — There are three varieties in the market — Arabic, Senegal, and salabreda; 
 these all exude from trees belonging to the Acacia tribe. 
 
 Without practical experience it is very difficult to distinguish between the 
 three above-mentioned varieties : gum arabic dissolves more readily in water, 
 and, as its solution has less tendency to become acid, it is better suited 
 as a thickener for bright and clear mordants; but, on the other hand, its 
 solutions are more readily coagulated by basic metallic salts than those of 
 
70 
 
 DYEING AND CALICO PRINTING. 
 
 Senegal gum. The solution of the latter gum in water is at first quite 
 colourless, but in a few hours it becomes very dark, sometimes as dark even 
 as an aqueous solution of Spanish juice. These gums contain a peculiar 
 principle, which is known as arabine, and also a very small quantity of an 
 organic lime salt, and variable quantities of chlorides of calcium and 
 potassium and acetate of lime. Arabine is insoluble in alcohol, and even in 
 weak spirits. Aqueous solutions of gum are therefore precipitated by these 
 fluids, and also by solutions of persalts of iron, nitrate of mercury, subnitrate 
 and subacetate of lead. The precipitate contains gummic acid combined 
 with metallic oxides. Boiling nitric acid converts gum into oxalic, tartaric, 
 and mucic acids. Solutions of gum turn the plane of polarisation to the 
 left. Allowed to remain, they are gradually converted into glucose. The 
 solutions of all varieties of gum very soon become acid, a fact of some 
 importance in reference to the use of gums as thickeners. When gums are 
 boiled for some length of time with dilute acids, glucosic acid is formed. The 
 soluble gums do not reduce the potassio-tartrate solution of copper unless 
 they are heated for some time with water either in sealed tubes or in a Papin 
 digester at a temperature of 302° to 320 F. (150° to 160 C.) 
 
 Gum Arabic. — East Indian gums and an Australian article are largely used 
 for manufacturing purposes, and these, together with samples of picked gum 
 Senegal, are substituted for the genuine gum arabic, which has become too 
 scarce to be used as a thickener. 
 
 Gum Senegal is chiefly used as a thickener; it is dissolved in water at 
 140 or even at 212 F. (6o° or ioo c C), and allowed to stand till the impurities 
 have settled, when it is passed through a fine hair sieve. It is employed 
 especially in printing with rollers. Gum solutions do not mix readily with 
 other thickeners ; with pipe-clay there is, however, an exception. It happens 
 occasionally that larger or smaller quantities of gum, insoluble in water, are 
 found among the soluble gums; when this is the case the material swells in 
 water, but does not yield a clear liquid. 
 
 It is worthy of observation that gum neither tarnishes nor alters delicate 
 colours, nor weakens the mordants ; that it does not coagulate colours, and 
 that on being dissolved in water it thickens rapidly. The action of gums 
 upon delicate colours is best tested with cochineal pink or fuchsine upon pure 
 wool ; after impression, the colour is steamed, and then washed, and if the 
 gum is pure there will be no trace of any yellow tinge or hue. 
 
 The action of gum upun mordants varies greatly, and depends very much 
 upon the degree of acidity of the aqueous solution. For certain colours it is 
 therefore absolutely necessary to use a very superior kind of gum ; this 
 applies especially to bright pink and rose-red. In order to estimate the 
 dissolving action exerted by gum upon mordants, an impression is made with 
 a mordant for bright rose-red, thickened with the gum to be tested. A 
 fabric mordanted with this mixture after having been treated in the usual 
 way, which is hereafter described, is placed in a madder-bath and cleansed 
 with soap, when it should produce a bright rose-red ; if the gum be acid 
 there is hardly any mordant left, and consequently no effect of dye is after- 
 wards to be seen. 
 
 Gums should possess the property of giving to water a certain degree of 
 viscosity without requiring an excess of material : this point is of far greater 
 
GUMS. 
 
 7i 
 
 importance than is often imagined ; for, supposing a manufacturer to require 
 annually a given quantity of gum of first rate quality, and to pay for that 
 quantity, say ^"3520, if the viscosity of the gum were reduced hy one-tenth, it is 
 clear that this would necessitate an outlay of £352 more. Several instruments 
 have been devised for measuring the viscosity of solutions of gum and other 
 viscous materials, and of these the least expensive and most simple appears 
 to be a glass funnel, the tube of which is drawn out to a fine point. Solutions 
 of gum are made in definite proportions, and the funnel having been filled, the 
 time that the several solutions take to run through is accurately noted, this 
 operation being shorter or longer according to the degree of viscosity of the 
 solution under treatment. M. Steilmann's viscosimeter consists of two hollow 
 glass cylinders, placed side by side, one of which is filled with pure water, 
 and the other with the solutions to be tested. Into each of these cylindrical 
 glasses (which are precisely similar) metallic balls can be let down. These 
 balls are suspended by silk threads, and move freely over pulleys ; they are, 
 however, partly counterpoised by means of weights. If the viscosity of the 
 liquids placed in the glass cylinders be equal, the metal balls will descend 
 with the same speed, provided, of course, that they are of the same size 
 and weight; but if one of the cylinders contain water, and the other a 
 solution of gum, the ball will sink into the latter more slowly than into the 
 former. The descent of the balls, when nearly at the bottom of the cylinder, 
 is stopped by a peculiar mechanical arrangement. M. Steilmann's apparatus 
 is in many respects an excellent one, but it is too complicated to be of great 
 practical use to those who require to test several samples of gum in a short 
 space of time. It should be borne in mind that although a solution may be 
 made of accurately weighed quantities of gum and water, the degree of 
 viscosity of such a solution is affected by the temperature of the water and of 
 the room in which the experiment is made. It is therefore necessary that 
 these experiments should always be made at the same temperature, 59 F. 
 (15 C), and it is also advisable to be provided with a freshly-made solution 
 of best quality gum that may be used as a standard of comparison. 
 
 Gum Tragacanth is the produce of the Astragalus vcrus, a tree growing 
 in Persia, Armenia, and Asia Minor. It is a white or yellow looking substance, 
 and is not really soluble in water, as it only swells in it, yielding a thick 
 mucilage. It contains on an average about half its weight of soluble arabine, 
 but consists principally of what is often called bassorine. Gum tragacanth 
 always contains some starch. Before being used it is soaked in cold water 
 for twenty-four hours, and afterwards boiled from four to six hours until a 
 thick homogeneous solution is obtained. The quantity of gum to 35 ozs. of 
 water varies from about 930 to 1530 grs. Though the solution made as 
 described is very thick and nearly colourless, it is less cohesive than gum 
 solution, and cannot therefore replace it. When gum tragacanth is boiled 
 with water, under a pressure of from four to five atmospheres, it yields in 
 about twenty minutes a thick solution. To test the viscosity of this gum 
 279 grs. are taken upon xjh ozs. of water; the fluid is boiled, and when it 
 has cooled down to 59° F. (15 C.) its viscosity is compared with that of a 
 solution of the same strength made from a good sample of the gum. 
 
 The mucilage produced by steeping linseed, the seeds of quinces, and 
 carragheen moss for some time in warm water, also affords a thickening 
 

 72 
 
 DYEING AND CALICO PRINTING. 
 
 material, but it cannot correctly be called a solution, and the mucilage is 
 rather pectine than true gum. 
 
 It is very difficult to give precise directions as to the quantity of thickening 
 required for the preparation of the colours, as this depends partly on the 
 viscosity of the thickeners themselves, and still more on the chemical action 
 exerted upon them by the colouring matters. For instance, where a certain 
 quantity of starch is sufficient for indifferent (neutral) solutions, or such as 
 become only slightly acid after boiling, half that quantity will suffice when 
 those salts are employed which exert a coagulative action, such as concentrated 
 solutions of sesquioxides, or caustic substances like soda. With sulphates 
 the result is different. 
 
 When gum is used a small quantity is generally sufficient with the larger 
 class of mordants (the solutions of sesquioxidts), but double the quantity 
 will be found necessary for indifferent solutions, proto-salts, &c. The more 
 basic any salt is, the greater is its tendency to coagulate ; the sesquioxides 
 have this tendency, but the proto-salts have not. Those substances which 
 possess the greatest thickening power, such as gum tragacanth and starch, 
 are not so suitable for printing purposes as the natural and artificial gums, 
 which are viscous and fluid at the same time. 
 
 We may here observe that gum acts in a peculiar manner with the acetate 
 mordants ; for instance, with proto-acetate of iron it has the effect of producing 
 paler tints than roasted starch. This peculiarity, which is generally believed 
 to be due to the acidity of gum solutions, appears, according to M. C. Kcechlin, 
 to be simply a hygrometrical effeft, as when glycerine or sal-ammoniac is 
 added to the pigment mixed with gum solution, the latter is restored to all its 
 superiority of action. 
 
(73) 
 
 CHAPTER IX. 
 
 ANIMAL FIBRES. THICKENINGS OF ANIMAL ORIGIN. 
 
 / T^HE classification of fibres according to their origin is important in a 
 scientific point of view, as it is based upon a difference of chemical 
 composition. A similar link of connection exists between wool and silk as 
 there does between hemp, flax, and cotton, the latter being intimately allied 
 to the neutral carbo-hydrates, while silk and wool belong to the nitro°-enous 
 albumenoid substances, which sometimes contain sulphur as well as nitrogen. 
 We are here led by analogy to the consideration of albumen, caseine, gluten, 
 fibrine, and gelatine, all of which now play an important part in the fixing of 
 colouring matter and pigments to woven tissues. 
 
 Albumenoid Substances. 
 
 These are very widely dispersed both in the vegetable and animal 
 kingdoms, though they are often considered to belong chiefly to the 
 latter. The number of these bodies is very large, but their characteristic 
 differences are not great. The chief substances of this kind which demand 
 attention in this work are albumen, fibrine, gluten, and caseine, to which 
 is often added the diastase of malt, diastase being the name given to albumen 
 in that state in which it effects the conversion of starch into dextrine and 
 cellulose. The plastic substances of the animal organism, as, for instance, 
 that membranous secretion called wool, the fibroine of silk, gelatine, and the 
 tissues which yield gelatine, on being boiled in water, are in some respects 
 similar to the albumenoid substances ; they differ from them, however, 
 sufficiently to admit of a separate classification. 
 
 The following table exhibits the composition of the most prominent of these 
 substances, many of which are only molecular modifications of each other: — 
 
 
 Albumen, Fibrine, 
 Caseine. 
 
 Epidermic 
 Productions. 
 
 G 
 
 datine yielding 
 Tissues. 
 
 Fibroine. 
 
 Carbon 
 
 •• 53'5 
 
 50 - 6 
 
 
 4938 
 
 50-5 
 
 Hydrogen . 
 
 . .. 7-1 
 
 7-0 
 
 
 651 
 
 7-0 
 
 Nitrogen . 
 
 .. i 5 -8 
 
 17*5 
 
 
 17-60 
 
 18-0 
 
 Oxygen 
 
 . .. ig-8 
 
 22'6 
 
 
 26-50 
 
 24-5 
 
 Sulphur 
 
 . .. i-8 
 
 2- 3 
 
 
 O'OO 
 
 o-o 
 
 The albumenoid substances are generally solid, and not capable of assuming 
 a crystalline shape : the protein substance of the blood globules has occasionally 
 been seen in a crystalline state. As to their solubility in water, this seems 
 to depend entirely upon certain salts or acids with which they are combined ; 
 
74 
 
 DYEING AND CALICO PRINTING. 
 
 in a pure state they do not appear to be at all soluble in pure water. Under 
 the combined influence of heat and moisture, or of mineral acids and some 
 metallic salts and organic compounds, these substances are converted into 
 allotropic modifications, whereby they become insoluble. Albumenoid sub- 
 stances, as a rule, are not soluble in alcohol, ether, or neutral organic liquids. 
 Exposed to a high temperature (that is to say, below red heat), these com- 
 pounds become decomposed, swell up, and fuse, yielding on dry or destructive 
 distillation a very large number of rather complex compounds according to 
 the degree of heat applied. Among these products we find sulphuretted 
 hydrogen gas and hydrosulphide of ammonium, ammonia, carbonate of 
 ammonia, aniline, picoline, pyridine, toluidine, pyrrol, methylamine, propyl- 
 amine, and tetrylaniine. A portion of the nitrogen combines intimately with 
 the carbon, yielding a nitride of carbon formerly employed in the manufacture 
 of cyanides. Water, carbonic acid, neutral oxygenated principles, and hydro- 
 carbons are simultaneously formed. 
 
 Albumenoid substances are more or less readily soluble in weak aqueous 
 solutions of caustic alkalies. The quantity of caustic alkali should be very 
 small, for if the solution be even as weak as 2 per cent of solid hydrate, a 
 decomposition of the albumenoid matter ensues in most cases, and minute 
 quantities of sulphuretted hydrogen are given off. These solutions are pre- 
 cipitated by acids, but the precipitate does not necessarily re-constitute the 
 identical substance. When heat and stronger alkaline solutions are simul- 
 taneously applied, ammonia, organic alkalies, carbonic and formic acids, 
 leucine, tyrosine, gelatine, and sugar are generated. When these substances 
 are fused with alkalies, an alkaline cyanide is obtained. The albumenoid, 
 called also protein, substances combine with both acids and alkalies, yielding, 
 with the former, compounds which are insoluble in acidulated water, but 
 soluble in pure water. 
 
 Concentrated acetic and other organic acids, and the hydrate of the tribasic 
 phosphoric acid dissolve albuminous substances ; these solutions are pre- 
 cipitated by an aqueous solution of ferrocyanide of potassium, which does 
 not precipitate the solutions in these same acids of gelatine and gelatine- 
 yielding tissues. Concentrated hydrochloric acid aided by heat yields with 
 the albumenoid substances, provided air be admitted, a solution which 
 assumes a rich blue-purple colour. Nitric acid has the effect of colouring these 
 substances deep yellow, owing to the formation of xanthoproteic acid, which, 
 on the addition of ammonia, assumes an intense orange colour. This property 
 of nitric acid is turned to account in the production of beautiful and fast 
 yellow and orange colours in woollen and silken fabrics and in feathers. A 
 solution of mercury in nitric acid (1 part of metal and 2 of nitric acid at 36 B.) 
 yields, when heat is applied, an intensely red colour with all albumenoid sub- 
 stances. These bodies are coloured deep brown with iodine. Strong 
 oxidising agents, such as chromic and permanganic acids, and a mixture of 
 sulphuric acid and peroxide of manganese, act very energetically upon the 
 albumenoid substances, producing a great many homologues of the fatty acid 
 series (C»H 2H 2 ) and the corresponding aldehydes; also benzoic acid, hydruret 
 of benzoyl, hydrocyanic acid, and the cyanides of methyl, ethyl, &c. 
 
 Ozone also acts upon some of these substances in a peculiar manner. When 
 albumenoid substances come into contact with air and moisture at a sufficiently 
 
75 
 
 ALBUMEN. CL , 6(c5 
 
 elevated temperature they undergo decomposition, which is accompanied by 
 the emission of foetid gaseous products. That absolute absence of moisture 
 prevents, to a great measure, that decay which is termed slow decomposition 
 is instanced in the preservation of the bodies of the dead monks in the vault 
 of the church at the Kreuzberg, near Bonn ; also of some bodies found in a vault 
 of the ancient church of St. Michel, at Bordeaux ; as well as by similar 
 effects in the leaden vault of the principal church at Bremen, and in the vault 
 under the choir of the church at Wienwert, a small village near Bolsward, in 
 Friesland. While in proof that there is no decay at lower temperatures than 
 o° C, may be cited the occurrence of the mammoths found in ice in Siberia in 
 a state of perfect preservation. The hair, nails, hoofs, horn, and wool and 
 silk, resist] decomposition for a long period, the resistance being due partly 
 to the small quantity of water which they contain, and which can be expelled 
 at ioo° C. (212 F.) According to M. Pasteur, this putrefaction, as it is 
 genetically termed, is due to the development of infusoria and vibrios, the 
 germs of which are conveyed by the air. Putrefaction may be entirely pre- 
 vented, besides, by the actions already mentioned, by the exclusion of air, and 
 by the destruction by means of heat of the pre-existent germs. Some sub- 
 stances known as antiseptic possess the property of arresting and preventing 
 decay, and consequently putrefaction. Among such substances are the 
 metallic compounds of copper, mercury, and arsenic ; the sulphites and 
 chlorides of sodium and potassium ; and among organic substances tannin, 
 carbolic acid, alcohol, &c. Gelatine, for instance glue, unless it is dry and is 
 maintained in a dry state, putrefies even more readily than albumen and.fibrine. 
 The chemical composition of the albumenoid substances is very complex, 
 and has not been completely elucidated. The composition cannot, therefore, 
 be expressed by a rational formala. Mr. Hunt describes these substances as 
 compounds of carbohydrates (cellulose, sugar, &c), with ammonia, less the 
 elements of water. Messrs. Dusart, Schoonbrodt, P. Thenard, P. Schutzen- 
 berger, and Guignet have obtained artificially nitrogenous substances, which 
 in many of their characteristics are similar to the nitrogenous substances 
 belonging to the animal bodies. This was effected by causing ammonia to 
 act upon sugar, cellulose, and similar substances at a temperature of 150 in 
 sealed tubes. Those substances often designated as epidermic, and also silk, 
 a secreted matter, and the cliondrogcn tissues, behave in many respects similarly 
 to the albumenoid substances as regards the reactions with heat, alkalies, 
 oxidising agents, nitric and hydrochloric acids, and nitrate of mercury. 
 
 Albumen. 
 Albumen is met with in the animal as well as in the vegetable kingdom ; 
 in the former it is found in its normal state, and in solution, in the serum 
 of blood, in the chyle and lymph, in all parenchymatous fluids, in muscle and 
 brain ; while the eggs of birds, the ova of reptiles and of fishes are composed 
 chiefly of albumen. The albumen in nearly all these substances is combined 
 with a larger or smaller quantity of an alkali, generally soda. Vegetable 
 albumen is not essentially different from that which occurs in the animal 
 kingdom. The sap of all plants contains albumen, which occurs also in most 
 leguminous seeds, and largely in the fluids known as latex and cambium. 
 All albuminous fluids from the vegetable kingdom exhibit in fresh state an 
 
7 6 
 
 DYEING AND CALICO PRINTING. 
 
 acid reaction. Albumen as it occurs in the organic bodies of animals and 
 plants is soluble in water ; but under the combined action of heat and water 
 albumen becomes entirely insoluble without any perceptible alteration in com- 
 position. This very characteristic molecular change is termed coagulation, 
 and is one of the most important properties of albumen. Pure albumen, 
 entirely deprived of the salts and alkalies, which in the natural state accompany 
 it, begins to coagulate at 59*5° C, the change being indicated by a slight 
 turbidity. The turbidity increases with the temperature up to 63" C, when 
 the formation of a flocculent mass commences, complete solidification ensuing 
 at 75 C. 
 
 The native solutions of albumen — for instance, white of egg — contain about 
 1*5 per cent cf soda. These solutions do not on coagulation form a flocculent 
 mass, but become gelatinous; the coagulation is never complete, owing to 
 the fact that a portion of the nitrogenous matter remains soluble under the 
 action of the alkali. If there occur a large excess of alkali coagulation does 
 not take place even at ioo° C. The action of carbonated or of caustic alkali 
 upon albumen is precisely similar. 
 
 Albumen enters into combination with baryta, strontia, and lime, forming 
 therewith insoluble compounds, which when dry are exceedingly hard. The 
 late Dr. Gerhardt held the view that albumen is a bi-basic acid, white of egg 
 and serum of blood containing the acid albuminate, while the coagulation 
 obtained under excess of potassa represents the neutral salt. M. Lassaigne 
 has shown that there can be produced double salts of albumen (or more 
 correctly albumine, since albumen is albumine plus certain salts and soda), 
 having sodium and copper as bases. 
 
 Albumen is coagulated, that is, converted into albumen insoluble in water, 
 by most of the mineral acids, and readily by nitric acid at the ordinary 
 temperature of the air. Pyrophosphoric and normal phosphoric acid, as well 
 as the vegetable acids, do not coagulate albumen. Alkaline salts added to a 
 solution of albumen do not effect any change at the ordinary temperature ; 
 but as the quantity of these salts is increased the coagulation of the albumen 
 by heat is retarded. Ferrocyanide of potassium, yellow prussiate of potassa, 
 precipitates in the cold all solutions of albumen after the previous addition of 
 some acetic acid. An excess of acetic acid causes the precipitate to be 
 dissolved. If an excess has been added accidentally, the application of gentle 
 heat will effect the precipitation of the albumen. Bichromate of potassa 
 precipitates albumen in the presence of vegetable acids. Several metallic 
 salts, as sulphate of copper, bichloride of mercury (corrosive sublimate), 
 nitrates of lead and silver, as well as alum, precipitate albumen from solution 
 or from the solution of an alkaline albuminate. But the precipitates thus 
 thrown down are generally soluble in an excess of the precipitant. Con- 
 centrated alcohol in excess at once effects the coagulation of albumen ; dilute 
 alcoholic solutions have the effect of retarding the coagulation of albumen 
 by heat. Tannic acid, aniline, creosote, carbolic acid, and other organic sub- 
 stances possess the property of coagulating albumen. 
 
 Coagulated albumen is a white, opaque substance exhibiting an acid reaction 
 to test-paper. After drying, coagulated albumen becomes yellow, transparent, 
 horn-like, and very brittle ; in this state it readily absorbs moisture, being 
 thereby increased in bulk. It is insoluble in cold water, becomes liquefied by 
 
ALBUMENOID SUBSTANCES. 
 
 77 
 
 long-continued boiling, and at the same time undergoes considerable modifi- 
 cation. Coagulated albumen possesses the property of combining readily 
 with a great many colouring materials, such as fuchsine, aniline violet, 
 purpuramide, and others, forming with them true organic lakes ; in this respect 
 albumine is very similar to wool. According to Dr. P. Schiitzenberger's 
 researches, coagulated albumen can be converted into soluble albumen, 
 and again coagulated by the application of heat : for this purpose coagulated 
 albumen* is dissolved in as small a quantity as possible of a weak solution 
 of caustic potassa. The solution of albuminate of potassa thus obtained 
 (free from other salts) is treated with an excess of acetic acid, the pre- 
 cipitate being submitted to dialysis, and the water frequently changed until it 
 is no longer acid. The water of the interior of the dialyser will, on examina- 
 tion, be found to exhibit a slight opalescence; and under the influence of 
 heat, as well as on addition of nitric and other mineral acids, there appears in 
 this fluid a heavy, flocculent precipitate. This precipitate occurs also on 
 adding the solution either of a neutral salt or a very small quantity of an 
 alkali. But fresh albumen when slightly acidified with acetic acid and sub- 
 jected to dialysis without previous coagulation, exhibit also these phenomena. 
 
 The sources of albumen available industrially are the eggs of birds, 
 especially those of the domesticated GalliHacecr, and the serum of blood. It 
 is a matter of regret that no substitute has been found for albumen, because 
 the number of eggs withdrawn from the food market for industrial purposes, 
 greatly increases the price of this very nutritive commodity. 
 
 The albumen employed in printing bears a double utility, serving as a 
 vehicle for the colour, and acting at the same time as a varnish. When 
 superfluous albumen colours are washed off after steaming, none of the albumen 
 is removed, but remains as an integral part of the pigment. This occurs in the 
 case of the so-called pigment colours, but in the fixing upon cotton of colours 
 derived from aniline the albumen is in effect; a true mordant, for having a great 
 affinity for aniline its action is similar to that of alumina or iron. Pigment 
 colours are fixed upon the cloth merely by the coagulation of the albumen, 
 which does not enter into combination with the colour, but with the cotton 
 fibre. 
 
 Albumen as white of egg is met with in commerce in the dry state, having 
 been submitted to a temperature of 30° to 35 C. upon zinc trays, slightly 
 greased with olive oil to prevent adherence of the albumen to the metal. 
 Eighty-four dozen eggs yield on average 6 litres (i - 2 galls.) of white in fluid 
 state, and 4 litres (o-88 gall.) of yolk. After drying 14 per cent of commercial 
 albumen is obtained. The yolk finds many applications, as in the dressing 
 of wash-leather, &c. The albumen obtained from blood has the disadvantage 
 of being dark in colour, and is inapplicable except in few instances. 
 
 No satisfactory substitute for albumen has yet been discovered; in Germany 
 glue is sometimes employed, the printed cloth being passed through a solution 
 of alum or an aluminous salt to fix the colour; but neither as to fastness 
 nor brightness of colour can this method be commended. Shellac dissolved 
 in borax, india-rubber dissolved in naphtha, and many other solutions have 
 failed. Drying oils have been used as vehicles for the pigment, but are 
 difficult of application ; yet were the investigations of Professsor G. J. Mulder 
 
 The albumen employed by Dr. Schutzenberger was obtained by Lieberkuhn's process. 
 
7 8 
 
 DYEING AND CALICO PRINTING. 
 
 on the chemistry of drying oils more generally known, undoubtedly these oils 
 would, in course of time, be extensively substituted for albumen. 
 
 Qualitative Testing of Albumen. 
 Dissolve about 5 grms. of the dried albumen in cold, pure water, in which, 
 if itself is pure, it should be perfectly soluble. Add a few drops of acetic 
 acid and filter the solution. There may remain insoluble, coagulated 
 albumen, caseine, and membranous matter ; the caseine may be dissolved by 
 treating the insoluble residue with a weak solution of caustic soda, whence 
 it is again thrown down by acetic acid. The clear filtrate is boiled, the 
 dissolved albumen being coagulated and thrown down as a flocculent pre- 
 cipitate. This precipitate is now removed by filtration, and to the filtrate is 
 added a solution of tannic acid in water in order to precipitate any gelatine 
 which might be present. Alcohol may next be added to precipitate gum and 
 dextrine. 
 
 Quantitative Estimation of Albumen. 
 The only important point is to ascertain the quantity of albumen coagulable 
 by heat, and this may be estimated by dissolving a weighed quantity, say 
 5 grms., of the sample in water, adding a few drops of acetic acid, filtering 
 if required, and boiling the filtrate for some time. The coagulated albumen 
 may then be collected upon a previously weighed filter, washed with boiling 
 water, again with alcohol and ether, dried at ioo° C, and weighed. 
 
 If a volumetric method be preferred, the following, by M. Scheurer-Kestner, 
 will be found advantageous: — The solution of the sample is diluted to half a 
 litre. From this 100 c.c. are taken, to which 10 c.c. of sulphuric acid are 
 added. Two standard solutions are required, one containing permanganate 
 of potash, the other protochloride of iron, so diluted that one volume of the 
 iron solution discolours or decomposes exactly one volume of the perman- 
 ganate solution. The protochloride of iron solution may be obtained by 
 dissolving 2 grms. of pure iron (pianoforte wire) in pure hydrochloric acid, 
 and diluting the solution to a litre. The permanganate solution is adjusted 
 to the iron solution volume for volume. Further, there is required a standard 
 solution of pure albumen containing 10 grms. to the litre. The relation of 
 this solution to the permanganate solution should also be accurately adjusted. 
 According to M. Thierry-Miey, this method gives excellent results within 
 5 per cent; but the gravimetrical method together with qualitative analysis 
 appears to be better suited to the estimation of the quantity of albumen 
 contained in a given sample. 
 
 Caseine, Fibrine, and Gluten. 
 Caseine is the chief nitrogenised constituent of milk. Milk, containing 
 about 12 per cent of solid matter, 3 per cent of which is caseine, 
 agrees in many of its chemical properties and its elementary composition 
 with albumen. Milk is not a solution ; but the chief of its solid constituents 
 are in a state of minute division, and the diversity of its solid constituents 
 greatly aids this mechanical admixture. Caseine, as contained in milk, is 
 combined with soda, forming therewith an albuminate identical with the 
 albuminate obtained when previously coagulated albumen combines with soda. 
 
CASEINE, FIBRINE, AND GLUTEN. 
 
 79 
 
 Some chemists admit the existence of two different kinds of caseine, one 
 of which is considered as capable of solution in water before coagulation. 
 That which is called soluble caseine is always more or less contaminated 
 with alkalies or salts, and attempts made to purify caseine by chemical 
 agents result in rendering the caseine much less soluble. It is generally 
 known that milk is coagulated, that is to say, the caseine it contains in 
 solution becomes, by the aid of a slight excess of alkali, solidified on the 
 addition of rennet or an acid, and also by the formation of la&ic acid (during 
 souring of the milk), at the expense of a portion of the sugar of milk, the 
 lactic acid combining with the alkali and causing the precipitation of the 
 caseine. 
 
 Legumine, contained in the seeds of plants of the natural order of Leguminosce, 
 is closely approximate to, but not identical with, caseine. 
 
 Caseine finds many useful applications in the arts and industries. Mixed 
 with lime it is employed in decorative painting; it enters into the composition 
 of several kits and mastics ; is used for glueing together the boxwood 
 employed for woodcuts; dissolved in a solution of borax it constitutes a highly 
 adhesive glue, which is used in fine joiners' work. A mixture of 6 parts of 
 calcined magnesia and i part of oxide of zinc with sufficient caseine to make 
 a paste yields, after desiccation, a perfectly white and very hard mass, which 
 admits a high polish, and appears somewhat similar to meerschaum. 
 
 Under the name of laclarine, caseine is employed as a mordant for fixing 
 pigment colours ; for instance, ultramarine. Under certain conditions the 
 results are moderately good, but great care and attention are required. 
 Ladfarine is insoluble before use, and has to be dissolved in an alkaline liquid, 
 such as ammonia or borax. The colours prepared with lactarine are liable to 
 decomposition, and a colour that may have worked well in the morning, in 
 the afternoon has been known to have changed either into a solid mass or a 
 curdy conglomerate totally unfit for printing, and not re-convertible into good 
 colour again by any means. 
 
 Several varieties of fibrine and gluten are known, but their chemical 
 characteristics do not exhibit great difference. The varieties are: — Fibrine 
 spontaneously separated from venous blood ; fibrine from arterial blood ; 
 fibrine from muscles ; glutine, or Beccaria's gluten after it has been exhausted 
 with boiling alcohol. All these substances are insoluble in water; when 
 boiled in water under pressure in a Papin's digester, they become soluble, but 
 are completely altered in their constitution, do not coagulate, nor gelatinise. 
 In acetic and mineral acids fibrine and gluten increase in bulk, and become 
 transparent and gelatinous. Extremely dilute aqueous solutions of caustic 
 potassa and soda dissolve these substances, and acids precipitate these 
 solutions. 
 
Mgi 
 
 (80) 
 
 CHAPTER X. 
 
 REVIEW OF THE METHOD OF APPLYING ALBUMENOID SUBSTANCES IN THE 
 FIXING OF COLOURS. 
 
 ' I * HE use of albumenoid substances for the fixing of colours has become so 
 "^ extended, that, notwithstanding the high price, there is a constantly 
 increasing demand for these materials. Their method of action is twofold. 
 In some instances there is a genuine chemical combination between the 
 colouring-matter and the nitrogenous albumenoid compound. When, for 
 instance, aqueous solutions of aniline violet (indisine), and albumen are 
 printed upon cotton, the colour when dry appears very dull and without gloss ; 
 also, it is not fixed, but may be removed from the cloth by simply steeping in 
 cold water. After steaming, however, the albumen coagulates, and a true 
 combination is formed between the colouring-matter and the albumen on the 
 one hand and the cotton on the other. In this instance the albumen acts 
 as a true mordant. But where albumen is employed to cause a very finely- 
 divided insoluble powder, as ultramarine, to adhere to cloth, and is next 
 exposed to steam-heat, it serves merely as an adhesive, and its action is 
 purely mechanical. This application of albumen is due originally to 
 M. Blondin de la Glacie're, who, in the year 1820, made the first attempt to 
 fix by means of albumen the brilliant blue colour derived from the lapis lazuli, 
 or native ultramarine. As might have been expected from the exceedingly 
 high price of native ultramarine, which is worth, weight for weight, more 
 than gold, the application remained inutilised for several years, owing as 
 well to the few varieties of pigments. Egg-albumen, as a fixing agent, was 
 introduced into this country in 1847 ; and among the many pigments applied 
 in this manner may be mentioned — Guignet's green, several ochrous com- 
 pounds of iron, vermillion, zinc-white, some chrome colours, and vegetable 
 lakes. 
 
 Albumen, in other words, white of egg, is best adapted to the practical 
 fixation of colour, and would be unrivalled were it not for its high price, and 
 for the consideration that its employment withdraws from use as animal food 
 an enormous quantity of eggs. The best mode of effecting the solution of the 
 dried commercial albumen is in tepid water, which should not be at a higher 
 temperature than 113 to 122° F. (45 to 50 C.) ; the albumen should be added 
 gradually, and the solution constantly stirred, to prevent the particles of 
 albumen agglutinising. The water should on no account be added to the 
 dried and powdered albumen. The proportion of dry material to the litre of 
 liquid varies according to the specific use for which it is intended, but 300 grms. 
 to the litre is an average quantity. Since white of egg can never be obtained 
 
FIXING OF COLOURS. 
 
 8i 
 
 quite free from particles of those membranes which line the inside of the 
 shell, the solution of albumen should always be carefully filtered through a 
 fine silk sieve, because the presence of small solid particles in the solution, 
 although they may be so small as to be invisible to the naked eye, causes 
 defects of a serious nature in the printing, viz., the production of dark coloured 
 specks upon the cloth. 
 
 Albumen of good quality is recognised by its transparency when in flakes, 
 by its taste being not disagreeable, and the odour free from that of putrefaction ; 
 it should dissolve readily in cold water with constant stirring. To prevent 
 frothing, and to render the albumen smooth in working, as well as to prevent 
 putrefa&ion, various additions are made, the material added being probably 
 not the same in any two places. Ammonia, turpentine, and oil are among 
 the principal agents added, but the quantities must be very small. A solution 
 of white bees'-wax in olive oil is sometimes advantageous; bees'-wax and not 
 Japan-wax should be employed. M. Zeller states that good results are 
 obtained by the addition of a certain quantity of fine olive oil to the dry 
 pigments previously to mixing them with the albumen solution ; when, for 
 instance, to 2 kilos, of ultramarine 500 grms. of oil are employed, the colour, 
 after fixing, will be at least 10 per cent deeper; and it follows that a smaller 
 quantity or an inferior quality of material may be used. In technical terms 
 the colour " goes further ; " while there is the very considerable advantage 
 that after the dressing of the goods they are much more flexible and much 
 smoother than when oil has not been added. In order to obtain good results 
 in cylinder printing it is frequently necessary to add gum to the albumen 
 colours. 
 
 A solution of albumen cannot under ordinary circumstances be expected 
 to be long kept free from putrefaction ; and true antiseptics have a coagulative 
 effect. It is therefore usual to employ oil of turpentine, which is added with 
 the twofold view of preventing frothing as well as putrefaction. Hyposulphite 
 of soda has been used, but with no good effect. But arsenite of soda, or 
 arsenious acid, commonly known as white arsenic, in the proportion of 
 T J th part by weight of the albumen, is not injurious to the colour, and, 
 according to M. C. Kcechlin, a high practical authority, the best preservative 
 of albumen solutions. 
 
 The following substitutes for albumen have been proposed : — An ammoniacal 
 solution of shellac for the fixing of ultramarine. Copal first softened in 
 aceton, and then dissolved in essence of lavender; fabrics treated with this 
 substitute may be washed in even boiling water. A solution of caoutchouc 
 in coal-tar oil, petroleum, or Persian naphtha has been successfully employed 
 for fixing ultramarine upon woollen stuffs ; the method answered well, but 
 has been abandoned on account of the inflammability of the solution, and 
 primarily on account of the discovery of the aniline colours. A solution of 
 resin in linseed oil has been substituted for albumen, as well as gum sandarach 
 and mastic dissolved in acetic acid, the latter not being employed with such 
 powdered colours as ultramarine. 
 
 In order to ascertain whether a colour is fixed with albumen, or with any 
 of its substitutes, the fabric should be momentarily immersed in boiling soap- 
 suds and slightly rubbed: well-fixed albumen pigments withstand this 
 treatment, but where substitutes are employed the colour scales off. 
 

 (82) 
 
 CHAPTER XI. 
 
 EPIDERMIC PRODUCTS. 
 
 •'PHE produces of the epidermis, the hair, nails, horn, wool, the scales of 
 some of the lower animals, skin, feathers, are all, chemically, the same 
 substance, but in a different state of aggregation. They are insoluble in 
 water, alcohol, and acetic acid. Solutions of caustic alkalies cause these 
 substances to increase in bulk at the ordinary temperature of the air, but 
 no real solution takes place; on being boiled with alkaline lyes, solution 
 simultaneously with decomposition sets in, ammonia being evolved. The 
 substances contain from 2 to 3 per cent of sulphur. Submitted to the action 
 of water boiling under pressure, in a Papin's digester, they dissolve with 
 difficulty, yielding solutions which do not gelatinise, a characteristic dis- 
 tinguished from that of the organic tissue of bones, cartilage, and the 
 epidermis. The most interesting of these epidermic produces is wool. 
 
 Wool, 
 This is a peculiar filamentous material secreted by the skin of sheep and of 
 some varieties of goats. The use of wool for spinning and weaving is of so 
 high an antiquity that it is impossible to say where and with whom it 
 originated, but wool was undoubtedly in use long before vegetable fibres 
 were employed. The cause of this early application is obvious when we 
 consider that wool possesses fineness, flexibility, and elasticity of fibre not 
 met with in an equal degree in any vegetable fibres. Further, wool is naturally 
 either white, yellow, or brown in colour, and can be more readily bleached, 
 while it assumes dyes more easily than vegetable fibre. The Commissioners 
 appointed to inquire into the best means of preventing the pollution of rivers 
 (Rivers Aire and Calder), say, speaking of the woollen trade : — "This trade is 
 of ancient date in England. The Romans had weaving establishments of 
 woollen cloth at Winchester, where the copious springs from chalk afforded 
 means both for power and for washing and dyeing. The mother of Alfred 
 the Great is recorded to have been skilled in spinning wool. Flemish woollen 
 weavers settled in England about the time of the Norman Conquest, and a 
 continued immigration of woollen weavers from Flanders took place in the 
 reigns of Henry I., Henry III., Edward I. and III. The woollen tissues first 
 spun and woven at Worsted, in Norfolk, about the year 1388, became the 
 staple trade of Norwich. Devonshire manufactured woollens soon after the 
 introduction of the trade into England, and Worcestershire a little later. 
 Friezes were also early manufactured in Wales. In the middle of the 16th 
 century Berkshire took the lead in woollen manufacture. About the 
 middle of the last century the West Riding of Yorkshire became the seat of 
 
WOOL. 
 
 83 
 
 the worsted and woollen trades. Halifax began to be specially noted for 
 kerseys. From about this date, these trades finding so much water available 
 not only for power, but also for washing, dyeing, scouring, fulling, and all 
 other purposes, the Yorkshire manufacturers and traders were enabled to 
 undersell those of other places. In the West Riding there are upwards of 
 5000 mills and dye works." 
 
 Wool, in the more restricted sense, and excluding such fibres as mohair, 
 alpaca, vicuna, and cashmere, is obtained only from sheep. There are two 
 chief species of sheep, viz., the mountain or highland sheep and the lowland 
 sheep. The native sheep of Germany and Spain, the merino sheep, and the 
 electoral sheep introduced into Saxony from Spain about 1765 — called electoral 
 because one of the Electors of Saxony was the importer— belong to the first 
 variety ; to the second belong the sheep found in the lowlands of Western 
 Europe and the Russian Steppes, and in this country. The species are further 
 divided, and named according to the county in which they are reared ; thus 
 we have Southdown, Leicester, Cotswold, &c. Wool derived from sheep bred 
 and fed for producing meat is inferior in quality and quantity to that of sheep 
 left to follow their natural instinctive selection of food. 
 
 Woollen fibre differs in many respects from that of cotton. Its quality 
 varies not only with the kind or species of sheep from which it has been 
 derived, but also with the part of the body of the animal from which it has 
 been taken. The best wool is that from the shoulders, the lower part of the 
 neck, the back, and sides. The length of the fibre varies from 40 to 180 m.m. ; 
 the thickness from 5 ' s to H ' s of a m.m. When seen under the microscope with 
 a magnifying power of 300 to 400 diameters, woollen fibres appear as a hollow 
 cylindrical tube with rings or projections in regular order, which in arrangement 
 have been compared to the scales of a fish, and these scales are, in fact, the 
 plates of the epithelium. Several of the peculiar properties of wool are 
 attributable to the scaled plates of the epithelium, such as the felting of wool, 
 the harshness felt by the fingers or lips when a fibre of wool is drawn in one 
 direction but not in the opposite, a property exhibited more strongly by hairs 
 than by wool. In working woollen cloths, they are, as is well known, liable to 
 " run up " or contract in certain dimensions, becoming thicker at the same 
 time. This action is produced purposely in fulling, accidentally by too 
 roughly handling woollen goods in washing and drying, and is attributable 
 to the construction .of the wool fibre, which may be regarded as an arrow or 
 a fish-hook easily moved in one direction, but not capable of returning. 
 
 Once a year the wool is shorn from the sheep and washed. By the washing 
 the wool loses 20 to 70 per cent of its weight. The weight of wool thus 
 shorn off varies from 3 to 12 lbs. per head of sheep. We may here again 
 quote from the Commissioners' Report on the Pollution of Rivers. " The 
 object of the washing is to remove ordinary dirt and the natural grease, as 
 well as that which has been applied to the fleece, and to open the wool to 
 the action of the dye. The wool is immersed in a copper filled with stale 
 human urine, diluted with water, and heated by steam. In this bath it 
 remains for a time varying from half an hour to two hours, when it is laid 
 upon a grating placed over the copper to drain, and then removed to another 
 vessel to be washed with cold water. The action of stale urine probably 
 depends upon the presence of free ammonia or its carbonate. Pig's dung is 
 
 g 2 
 
84 DYEING AND CALICO PRINTING. 
 
 sometimes employed instead of, or in combination with, the urine. Other 
 substances, such as soda-ash, phosphate of soda, and salts of ammonia, are 
 sometimes substituted or added to this bath, but the favourite material seems 
 to be stale human urine. The wool, after being drained, is washed in cold 
 water. In the smaller mills this is performed by stirring up the wool in a 
 tank of water with a strong pole, the water being let off through a " clow" 
 or shuttle, furnished with a grating, at the bottom of the vat, which i6 again 
 filled with cold water, the water being renewed several times in succession. 
 In late years a machine known as Petrie's wool-washing machine has been 
 introduced. The wool, steeped as before, is here immersed in water contained 
 in long tanks, and is made to pass forwards, being at the same time opened 
 out by an ingenious arrangement of rakes worked by machinery. The 
 principle in this case is to introduce the wool to liquid which is already 
 fouled by having passed over a first portion, and so gradually to bring it into 
 contact with clean water at the other end. Three or four of these vessels are 
 placed in series, and the wool transferred from one to the other by endless 
 bands of wire gauze. The wool is put into a tank, from which the waste 
 water flows away, and issues from the tank to which the clean water is sup- 
 plied. The use of this machine offers an opportunity of economising water, 
 which is of great advantage when the supply is limited. This ' scour' water 
 runs, in either case, from the vats to the nearest outfall. There is nothing in 
 it that is considered worth saving, and we have not heard of its ever having 
 been turned to account or treated in any way. If the wool is not to be dyed, 
 or is to be removed from the premises for that purpose, or if it is to be woven 
 before being dyed, it is dried in hot chambers of various constructions." 
 
 The following analysis of raw merino wool, by M. Chevreul, exhibits the 
 composition after drying at ioo°. In ioo parts by weight — 
 
 Earthy matter deposited by washing the wool in water . . . . 26-06 
 Suint, a peculiar saponified grease, soluble in cold water . . 3274 
 
 Neutral fats 857 
 
 Earthy matters obtained after the fatty substances were elimi- 
 nated 1-40 
 
 Textile fibre 31*23 
 
 Faist gives the following analysis of various wools : — 
 
 Hohenheim Wool Hohenheim Hungarian Wool 
 
 (raw). (washed and dried), (washed and dried). 
 
 Mineral matter . . .. 6-3 16-8 0-94 ro 
 
 Suint and fatty matter 44*3 44*7 2i - oo 27*0 
 
 Pure wool 38-0 28-5 72-00 64-8 
 
 Moisture 11-4 7-0 6 - o6 7-2 
 
 ioo*o ioo-o ioo - oo ioo-oo 
 
 Eisner has found that the loss of weight in wool, treated for the elimination 
 of the suint with bisulphide of carbon, varies from 15 to 70 per cent with 
 washed merino wool, 50 to 80 per cent with unwashed wool, and with long or 
 carded wool 18 per cent. 
 
 Suint contains oxalate of lime, chloride of potassium, silica, valerianic acid, 
 two potash salts containing peculiar fatty acids and some fats none of which 
 
WOOL. 
 
 »5 
 
 are found in the body of the sheep in that peculiar state. The fibre itself, 
 after having been treated with water, alcohol, and ether, still contains o'3 to 
 o - 5 per cent of ash, composed of phosphate of lime and magnesia, sulphate 
 and carbonate of lime, silica, and peroxide of iron. The organic substance of 
 the fibre, often called keratine, consists of a proteinoid substance, containing 
 or combined with large quantities of sulphur, a considerable proportion of 
 which is readily removed by the action of alkalies. When wool is steeped in 
 plumbite of soda — a solution of oxide of lead in caustic soda — the fibre 
 becomes coloured black, owing to the formation of sulphide of lead, due to 
 the sulphur naturally contained in the wool. At 150 F. wool gives off sul- 
 phurous odours ; even during the boiling of wool and woollen fabrics in water 
 — flannel, for instance — an odour of sulphur is perceptible. Hence it follows 
 that, in dyeing wool with bright colours, contact with metallic surfaces, and the 
 presence of salts of lead, copper, and tin must be carefully avoided. Especially is 
 this the case with steam-colours. The intelligent Directeur de la Manufacture 
 des Gobelins, at Paris, eliminates the sulphur from the wool used in that 
 establishment by soaking the wool for twenty-four hours in milk of lime, at 
 the ordinary temperature of the air, and then washing the wool in dilute 
 hydrochloric acid, and afterwards in water. It appears, however, that even 
 when this treatment is repeated twenty-eight times, for forty-eight hours each 
 time, all the sulphur will not have been eliminated, and there may even then 
 remain 0*46 per cent of sulphur ; but the wool is no longer coloured by contact 
 with plumbite of soda. 
 
 Wool deprived of naturally-adhering grease, and heated to 160°, assumes a 
 yellow tinge, which is deeper when the wool has previously been de-sulphured. 
 If the wool has not been deprived of the grease adhering to it naturally, it 
 becomes, when heated to 160 , coloured brown. Heated to 130 wool gives off 
 ammonia, and, similarly to most protein compounds, wool does not admit of 
 being heated beyond 120 , in a current of dry air, without suffering decompo- 
 sition. Schweitzer's reagent does not act upon wool at the ordinary tempera- 
 ture of the air, but it dissolves wool when heat is applied. Chlorine and 
 hyperchlorous acid attack wool at the ordinary temperature, causing it to 
 assume a yellow colour ; hence wool and woollen fabrics cannot be bleached 
 by chlorine. Nitric acid, even when dilute, colours wool yellow, forming 
 xanthoproteic acid: this property is sometimes utilised in the printing of 
 patterns upon woollen fabrics, especially such as have previously been dyed 
 blue with indigo, for the nitric acid, in destroying the indigo, gives a deeper 
 shade of yellow. Caustic alkalies disintegrate and dissolve wool very rapidly; 
 strong ammonia acts injuriously upon wool, causing it to become rapidly dis- 
 integrated. The solutions of the alkaline carbonates and of soaps, if not too 
 concentrated, and if at a lower temperature than 6o°, do not perceptibly affect 
 wool and its tissues. 
 
 When wool is ignited it burns slowly, emitting a very disagreeable odour, 
 similar to that given off by burning horn. A woollen thread held in the flame 
 of a candle leaves a voluminous coke, which remains hanging at the end of 
 the thread. This property is often employed in the detection of woollen 
 fibre. 
 
 Wool, especially when roughly washed and purified, is very hygroscopic, 
 and though dry to the touch may have absorbed between 7 and 8 per cent of 
 moisture. The behaviour of wool towards colouring matters and dyes is 
 
86 
 
 DYEING AND CALICO PRINTING. 
 
 entirely different from that of vegetable fibres. It forms, with some soluble 
 colouring materials, genuine compounds or lakes, and acts generally in this 
 respect as do all protein substances. Several salts, including alum, are pre- 
 cipitated by wool from their aqueous solutions, and retained in the wool by a 
 special attractive force. Wool has the property, also, of reducing the peroxides 
 of some of the metals, including iron, to protoxides. 
 
 Before wool is ready for the spinner it has to undergo, as already described, 
 a process of washing, in order to remove the dirt accidentally adhering to it, 
 and to eliminate that natural grease which protects the animal from the chills 
 which would be consequent upon the thorough saturation of its coat with rain. 
 As this grease has been found to contain a large quantity of a very pure car- 
 bonate of potassa, Messrs. Maumene and Rogelot have devised a method of 
 extracting the potassa-salt, so as to obtain from every iooo kilos, of wool 
 about 75 kilos, of the carbonate. The method consists in steeping the wool 
 in tepid water (35 to 40 ), employing repeatedly the same liquid, and main- 
 taining the heat by the occasional admission of steam when fresh quantities 
 of wool are put into the tanks, or rather tubs, wooden vessels being employed. 
 The liquid, when as much saturated with saline matter as possible, is run off, 
 evaporated to dryness, and the residue ignited. The complete elimination of 
 fatty matter from the wool is effected by washing in weak alkaline liquids, 
 partly composed of putrid human urine (carbonate of soda), partly of carbonate 
 of soda. 
 
 Bleaching Wool. 
 
 The bleaching of woven woollen tissues, or also of woollen yarn (a large 
 proportion of the wool employed is dyed before weaving), includes numerous 
 operations, some of which are of a mechanical nature, as, for instance, the 
 firing or removal by singeing, or in some cases by shaving or shearing off, the 
 loose, downy threads. The woollen fabric is never dyed with the view of 
 preserving any part of it white, because affinity of the fibre for colours is so 
 great that it takes them without any mordant, and whites therefore could not 
 be kept clear in dyeing. For this reason, also, the loose hairs on the cloth 
 may be shaven to any degree of closeness. 
 
 The bleaching of wool is not a matter of great difficulty, and is far less 
 laborious than the bleaching of cotton and linen. From the chemical nature 
 of the wool it will be gathered that it is impossible to apply to it materials of 
 the same strength and temperature as are applied to cotton and linen. The 
 process of bleaching woul is u repetition of gentle treatment with soap and 
 very weak alkalies (carbonates) ; but when the woollen fabric is required to be 
 dyed with light or bright colours, or is to be printed, the ground must be 
 white, and the process of sulphuring resorted to. This was formerly effected 
 by hanging the moist pieces for several hours in chambers filled with sul- 
 phurous acid gas, or vapours of burning brimstone. It is now performed by 
 Mr. Thorn's process, in a few minutes, by passing the goods over a number of 
 rollers confined in a small chamber filled with the same vapours. According 
 to Mr. Girardin (a great authority in all matters relative to bleaching, dyeing, 
 &c), M. Pion, at Elbeuf, the seat of an extensive woollen industry in France, 
 obtains excellent results by employing a solution of sulphite of soda acidified 
 with hydrochloric acid, in which the woollen tissues are steeped for some 
 hours, being next thoroughly washed, — an operation equally indispensable after 
 
BLEACHING WOOL. 
 
 87 
 
 sulphuring with gas, because there is generated in the fabric a small quantity 
 of sulphuric acid, which, unless removed by washing, would during the drying 
 tend to destroy the fibre. Woollen fabrics intended to be dyed with dark 
 colours are never bleached by sulphuring. Cloth intended to remain white is, 
 after the sulphuring and washing, passed through a bath containing some 
 indigo-carmine, in order to increase the intensity of the whites. According 
 to M. Schlumberger, skeins of woollen thread can be excellently bleached by 
 washing them thoroughly in a strong soap solution, at a temperature of 50 , 
 and suspending them wet during the night in a chamber filled with sulphurous 
 acid gas. The skeins are then dried, without being again rinsed. When the 
 wool is intended to be dyed it is put, immediately after being taken from the 
 sulphuring room, into a bath of dilute sulphuric acid, and next thoroughly 
 washed in cold water. 
 
(88) 
 
 CHAPTER XII. 
 
 PRACTICAL RECIPES IN CONNECTION WITH WOOLLEN YARN AND FABRICS. 
 
 Bleaching. 
 T N quantities of ioo ibs. The process is very simple. The scourer should 
 have care that his kettle is not hotter than 132 F., and that the wool 
 does not lie in the bath long enough to become yellow. The goods or yarn 
 are scoured in clean soap, as usual, and then hung up in a closed chamber or 
 bleach-house, exposed to the vapour of sulphurous acid, produced by burning 
 in an iron pot 6 or more pounds of brimstone. When yarn is bleached for the 
 market, it should be put into the sulphur-house without the soap being rinsed 
 out, only switched out well. If the white has to be coloured, the wool should 
 first be run through a cold bath, containing 2 lbs. of muriate of tin, 2 02s. of 
 extract of indigo, 3 ozs. of cochineal paste.* Red, blue, and yellow form 
 white, and the wool is naturally yellow ; hence the method of treatment. 
 Then take the wool into the sulphur-house. The fabric ought never to be 
 coloured after sulphuring, as it will become spotted. Carpet-yarn may be 
 afterwards run through a bath containing 5 lbs. of whiting : this somewhat 
 neutralises the offensive odour. Care should be taken in bleaching part cotton 
 goods when poles or slats are employed ; the wood absorbs sulphuric acid, and 
 will rot the cotton if in contact with the cloth. The poles should be often 
 washed or planed. 
 
 Another Method of Bleaching. 
 
 In the case of a large quantity of goods for printing, it is more convenient 
 to bleach them in large vats filled with water, charged with sulphurous acid, 
 as follows : — 
 
 Half fill a stone pot with pine sawdust, and cover it with a wooden cover 
 through which is a hole to receive a lead or glass pipe. Pour enough sulphuric 
 acid to cover the sawdust, and insert the pipe which conduces the sulphurous 
 acid gas into the vat of water, rendering the joint gas-tight by a luting of 
 clay. To prevent too much free acid going over, the gas may be passed 
 through a strong solution of soda, and then to the vat. The vat, of course, 
 should be covered. The goods are thrown into the water over-night, and when 
 taken out will be found sufficiently bleached. 
 
 This method, when modified, will be found advantageous in bleaching the 
 whites of goods coloured chrome-black, should such a process be required. 
 
 * Cochineal paste is obtained by placing 10 lbs. of Honduras cochineal in a vessel, and 
 adding 30 lbs. of ammonia water (17 B.), stirring the mixture well. The vessel should be 
 covered with a cloth, and allowed to stand for a few days. The vessel is then to be immersed 
 in boiling water, in order to evaporate the superfluous ammonia; when the evaporation is 
 complete the mixture is ready to be used. The ammonia may be condensed during the evapo- 
 ration, if employed in large quantities. 
 
Plate II. 
 
 Plan of the Dye Works of Boutarel and Co., Clichy-la-Garenne. 
 
 a, Entrance, n, Lodge, c, Warehouse, Offices on the first floor. D, Chemical Laboratory. E, Mill 
 for Chipping Dye-woods. F, Mill for Wares. G, Boilers for Extracting Dye-woods. 
 H, Steam-boilers. I, Engine-house, j, Water Tanks. K, Singeing-house. L, Crabbing- 
 house. M, Draining-house. N, Dye-houses, o, Washing and Drying, p, Stretching Pieces 
 on first floor, Examination of Pieces, g, Croppers in the first floor, finishers on tho 
 ground floor. R, Pressing-house, s, Trimmers. T, Shawl-house, u, Mechanics' Shop, 
 v, Store of Materials, x, Lodgings of Persons employed, y, Yards and Passages. 
 z, Chimney. 
 
COLOURS ON WOOLLENS. 
 
 S 9 
 
 To each piece of fabric dissolve i lb. of hyposulphite of soda in 2 pails of 
 water, to which add 1 lb. of sulphuric acid, the vessel containing the mixture 
 being well covered, so as not to lose any sulphurous acid gas. All the sulphur 
 must be allowed to settle until the liquid is clear, and the liquid may then be 
 run into a clean tub filled with water. In this bath the goods are to be laid 
 for 6 to 8 hours, when the whites will be found perfectly bleached without 
 injury to the black. Rinse, and dry. 
 
 COLOURS ON WOOLLENS— BLUES. 
 Woad. 
 
 Woad alone was used for colouring wool blue before indigo was intro- 
 duced into Europe. The introduction of indigo was a great advantage to 
 the dyer, not only for its intrinsic value, but because he could daily strengthen 
 his vat, using the old woad as a fermenting agent, like yeast in making bread. 
 As to the practical value of the different varieties of indigo, it maybe said that 
 4 lbs. of good Bengal are equivalent to 5 lbs. of good Guatemala indigo. 
 
 In order to colour with indigo we have to deprive it of its oxygen. The de- 
 oxidised indigo is yellow, and in this state penetrates the woollen fibre ; the 
 more perfectly the indigo in a vat is deoxidised, the brighter and faster will 
 be the colour. 
 
 To a vat 8 feet deep by 6 feet wide, filled with water, and heated by steam or 
 otherwise to 140° F., add 200 lbs. of woad, about 10 lbs of well-ground indigo, — 
 or more, according to the amount of work to be done, — 5 lbs. of soda, £ a bushel 
 of good wheat-bran, 10 lbs. of good madder, and 1 lb. of flour. If the soda, 
 bran, madder, and flour are boiled for five minutes before adding them to the 
 vat, it will ferment twelve hours earlier than it would otherwise do. Stir the 
 vat well, and after eight hours' rest again stir. The vat by this time should 
 have commenced to ferment, the liquid acquiring a mottled appearance. When 
 the fermentation is well established, add about 2 lbs. of slaked lime, and again 
 stir. If sufficient lime has been added, the surface of the vat will reflect a 
 golden colour; and a sample of wool immersed in the liquid for about twenty 
 minutes should become perfectly coloured blue in one minute. A green colour 
 remaining with the wool after one minute shows that more lime must be 
 added. Should this addition be neglected, the vat will be, as it is termed 
 technically, " lost." The lime added should be mixed with water, and 
 the solution filtered. A vat, to which too much lime has been added, or 
 which has become " over-sharpened," acquires a brown colour, and the wool 
 immersed in the liquor is imperfectly coloured a grey-blue. 2 or 3 lbs. of 
 sulphuric acid may be added in such a case to form with the lime a neutral 
 sulphate, which settles to the bottom of the vat. After the addition of the 
 sulphuric acid a mixture of 5 lbs. of bran and 5 lbs. of madder boiled together 
 should be added. Fermentation is thus again set up, and can be reduced by 
 lime as before. When the vat is exhausted ; and more indigo must be added, 
 care should be taken that the liquor is sharp enough. The liquor should again 
 be warmed, and the indigo added with about 6 lbs. of madder, 6 lbs. of bran, 
 and 2 lbs. of soda, boiled together as before. The indigo should be added 
 over-night, in order that fermentation may be complete by the morning. In 
 the morning lime must be added until the golden film forms on the surface of 
 the liquid. 
 
go 
 
 DYEING AND CALICO PRINTING. 
 
 Soda or Potash Vat. 
 
 By boiling 10 lbs. of indigo in a solution of 4 lbs. of caustic soda or potash, 
 and adding 2 lbs. of feathered tin, or 3 lbs. of tin crystals, the indigo is 
 deoxidised by the strong affinity of the tin for the oxygen. The ordinary 
 method of fermentation is, however, to be preferred, as a larger quantity of 
 work can be got through. But the soda vat is preferable for light blues, as 
 a brighter colour is obtained than by the woad vat, while larger quantities of 
 goods may be coloured more easily. Potash should be employed for linen and 
 cotton. 
 
 A Decomposed Vat. 
 
 A decomposed, or, as it is termed, a " sick " or " green " vat may be known 
 by its dark colour and freedom from odour, and more certainly by the addition 
 of lime, bran, madder, and soda, or of woad. If, after several hours, the vat 
 is restored, it may be worked with care as a new vat. 
 
 Applications of the Woad Vat. 
 The applications of the woad vat, as well as many practical recipes relating 
 to the colouring of wool, we shall, for facility of reference, include in this 
 chapter. 
 
 Indigo-Blue on Wool for Topped Hosiery. 
 
 100 lbs. of wool are coloured with 4 lbs. of Guatemala or 3 lbs. of Bengal 
 indigo, in the woad or soda vat. There is then prepared by boiling for a few 
 minutes 5 lbs. of cudbear or 8 lbs. of orchil paste, adding to the mixture 1 lb. 
 of soda, or an equivalent quantity (about one pail) of urine. The beck must 
 be cooled to 170 F. before the wool can be entered. It should be handled for 
 twenty minutes, taken out, rinsed, and dried. 3 ozs. of aniline purple dissolved 
 in half a pint of alcohol can be used instead of the cudbear. The shade pro- 
 duced is very pretty, but ought never to be used for mixed goods, which have 
 to be bleached, as it runs into whites. The cudbear, too, is affected by 
 sulphuring. 
 
 Dark Blue, for Wool for Broadcloth. 
 
 A healthy woad vat is employed for this colour. The wool is handled 
 slowly for one hour, then removed ; after two hours it can be again dipped 
 until it has acquired the desired shade. Enough indigo should be added to 
 the vat to colour the wool in three immersions ; that is, about 10 lbs. of good 
 indigo to 100 !bs> of wool. The wool may with advantage be taken through 
 a warm bath containing 2 lbs. of sulphate of copper; this additional immersion 
 renders the colour faster in fulling. A dark blue, very common in the market, 
 is topped with camwood or red Sanders, the latter being boiled on the 
 coloured wool. 
 
 Topped Logwood Blue. 
 
 Dip in the blue vat and then rinse. Boil the wool thus dipped for one 
 hour in a kettle containing 10 lbs. of alum, 2 lbs. of crude tartar, and i£ lbs. 
 of sulphate of copper. Remove and cool. To some fresh water add 5 to 10 
 lbs. of logwood (according to the shade required, and the quality of the 
 logwood) in a bag. Boil, and then cool the kettle to 170 F. The wool may 
 now be entered and handled slowly ; in one hour it may be cooled, rinsed, and 
 switched for drying. 
 
COLOURS ON WOOLLENS. 
 
 9i 
 
 Indigo-Blue, part Logwood. 
 
 For 100 lbs. of cloth. Colour the cloth in the indigo-blue vat, and rinse 
 well. Then boil the cloth in a bath of 20 lbs. of alum, 2 lbs. of tartar, 5 lbs. 
 of pensee mordant or purple acid,* for two hours. Remove and cool. To a 
 kettle of fresh water add 10 lbs. of logwood in a bag, boiling for half an hour. 
 Cool to 170 F., and enter the wool, boiling half an hour. Cool and rinse. 
 
 Purple Blue. 
 
 For 100 lbs. of wool. The wool is first coloured lightly in the blue vat. 
 It is then boiled in a solution of 15 lbs. of alum and 3 lbs. of tartar for one 
 and a half hours. Remove, cool, and drain for twenty-four hours. In a 
 kettle of fresh water boil 8 lbs. of cochineal powder for ten minutes. Cool 
 to 170°, and enter the wool for one hour ; boil for three quarters of an hour, 
 rinse, and dry. 
 
 Chrome Blue. 
 
 For 100 lbs. of wool. Boil the wool for one hour in a solution of 3 lbs. of 
 bichromate of potash, 6 lbs. of alum, 1 lb. of tartar. Remove, cool, and 
 rinse. In a kettle of fresh water boil 6 lbs. of logwood for half an hour, add 
 3 lbs. of dissolved cudbear. Cool to 180° F., and enter the wool, boiling and 
 handling for three quarters of an hour. As chrome colours always darken in 
 drying, the shade, on removal from the bath, must be lighter than that desired 
 in the finished fabric. 
 
 Dark Indigo Blue. 
 
 For 100 lbs. of cloth. Boil for one hour and a half in a solution of 20 lbs. 
 of alum, 4 lbs. of tartar, 6 lbs. of pensee mordant, 6 lbs. of extract of indigo. 
 Remove and cool. Prepare a fresh kettle of 8 to 10 lbs. of logwood, in which 
 boil the fabric for one hour. 
 
 Saxony Blue. 
 
 For 100 lbs. of thibet or combed yarn. Dissolve 20 lbs. of alum, 3 lbs. of 
 tartar, 2 lbs. of pensee mordant, 3 lbs. of extracl of indigo, or, better, 1 lb. of 
 carmine, in hot water. Cool to 180 F. ; enter the material, and boil until the 
 colour becomes even. Too long boiling should be obviated by well and 
 quickly handling. 
 
 It is necessary to handle coarse carpet-yarn through a beck heated to 170 F., 
 and containing 15 lbs. of alum, 10 lbs. of sulphuric acid, 4 lbs. of chemic 
 paste or sulphate of indigo.f Under the influence of sulphur the colour 
 becomes of a stone-green shade, but is restored by rinsing in water. 
 
 Fast Prussian Blue. 
 
 For 100 lbs. of wool or flannel. Dissolve 8 lbs. of red prussiate of potash 
 (ferricyanide of potassium), 2 lbs. of tartaric acid, 2 lbs. of oxalic acid, and 
 the following mordant in water heated to 208 F., in which the goods are to 
 
 * This mordant can be prepared by mixing in a stone vessel 5 lbs. of tartar, 5 lbs. of feathered 
 tin, with 25 lbs. of muriatic acid. To this mixture is added 15 lbs. of sulphuric acid diluted with 
 10 lbs. of water; then very slowly 2 lbs. of nitric acid. 
 
 ■i Sulphate of indigo may be roughly prepared thus: — To 30 lbs. of sulphuric acid (67 B.), 
 add slowly 10 lbs. of pulverised fine Bengal indigo. Stir until all is well mixed. After two 
 days add slowly 10 lbs. of water. 
 

 
 Q2 
 
 DYEING AND CALICO PRINTING. 
 
 be well handled for one and a half hours. Then remove, allow to drain, 
 rinse, and dry. 
 
 The mordant. Add i ib. of feathered tin to 10 lbs. of nitric acid (36* B.), 
 10 lbs. of hydrochloric acid (22 B.), 10 lbs. of sulphuric acid (66° B.), diluted 
 with water. 
 
 Some dyers themselves prepare the red prussiate of potash by passing 
 chlorine (obtained by the adtion of sulphuric acid upon manganese and salt) 
 through a leaden pipe into a solution of yellow prussiate of potash. A dark 
 olive liquid is produced, which yields on evaporation crystals of red prussiate. 
 When nitrate of iron no longer produces a blue colouration enough chlorine 
 has been taken up. The olive liquid can be employed without crystallisation. 
 
 Aniline Blue. 
 For 100 lbs. of fabric. Dissolve i\ lbs. of aniline blue in 3 quarts of boiling 
 alcohol. Filter the solution, and add the clear filtrate to a bath of water at 
 130 F., together with 10 lbs. of sulphate of soda, and 5 lbs. of acetic acid. 
 The goods are now to be entered and handled for twenty minutes, when the 
 temperature of the bath is to be slowly raised to 200 F. At this temperature 
 add 5 lbs. of sulphuric acid diluted with water, Boil for twenty minutes, 
 rinse, and dry. The aniline blue should be added in two or three quantities 
 in order to render the colouring of equal quality throughout. Closely woven 
 fabrics, braid, &c, should be prepared in a boiling solution of 10 lbs. of 
 sulphuric acid and 2 lbs. of tartaric acid before colouring with the aniline. 
 
 REDS ON WOOL. 
 Scarlet. 
 For 100 lbs. of fabric. Boil for fifteen minutes 11 lbs. of Honduras 
 cochineal, 5 lbs. of tartar, or 3 lbs. of tartaric acid, 2 lbs. of oxalic acid, 1 lb. 
 of tin crystals, i£ lbs. of flavine, 10 lbs. of muriate of tin (see footnote, p. 91) 
 Cool to 180 F., and enter the goods, boiling for one hour. Remove, cool, and 
 rinse. 5 lbs. of hydrochloric acid added to the beck will prevent the 
 appearance of undyed filaments of wool, &c. This addition is attended with 
 good results in all kinds of scarlets, orange, and pinks. 
 
 Scarlet (Lac-Dye). 
 For 100 lbs. of flannel or yarn. Boil in water for fifteen minutes 25 lbs. of 
 lac-dye, 15 lbs. of muriate of tin, 5 lbs. of tartar, 1 lb. of flavine (the quantity 
 of which may be varied according to shade), 1 lb. of tin crystals, 5 lbs. of 
 hydrochloric acid. Cool to 170° F., and enter the goods, boiling for one hour. 
 Rinse whilst hot. This is a faster colour than 
 
 Cochineal Scarlet. 
 
 For 100 lbs. of fabric. Dissolve in water 10 lbs. of nitrate of tin, 5 lbs. 
 of cream of tartar, and 1 lb. of flavine. Boil the solution for ten minutes, 
 and cool to 170 F. Enter the goods, boiling for one hour. Remove, cool, 
 and rinse. 
 
 To a kettle of fresh water add 7 lbs. of cochineal and 2 lbs. of starch in 
 solution. Strain, and then boil for five minutes. Cool to 180 , and then add 
 
COLOURS ON WOOLLENS. 
 
 93 
 
 I lb. of nitrate of tin. Enter the fabric and boil for three quarters of an hour. 
 Remove> cook, and rinse. 
 
 Ponceau. 
 Colour scarlet, as for scarlet dyeing, but without 
 Then well rinse the goods. Prepare a kettle of 
 into which put 5 lbs. of cochineal paste (see p. 88). 
 Rinse and dry. Magenta crystals 
 
 For 100 lbs. of fabric, 
 flavine or yellow dye-stuff 
 fresh water heated to 180 
 Stir, and enter the fabric without boiling 
 may be substituted for the cochineal. 
 
 Pink for Listings. 
 For 100 lbs. of wool. Boil together, until dissolved, 8 lbs. of cochineal, 
 5 lbs. of tartar, 10 lbs. of muriate of tin, J lb. of tin crystals. Cool to 170° F., 
 and enter the wool, boiling for half an hour. Should the wool not colour 
 evenly add a few lbs. of hydrochloric acid. If the listings are to be on white 
 flannels, add about 6 lbs. more of muriate of tin to the beck before removing 
 the wool. To prevent the colour running the scourer should add a solution of 
 
 1 lb. of hydrochloric acid to the last rinsing of the flannel. Should the 
 cochineal have been smeared upon the white it should be well rinsed out with 
 cold water before sulphuring. 
 
 Madder Red. 
 For 100 lbs. of fabric (generally cloth for army uniforms). Dissolve 20 lbs. 
 of alum, 5 lbs. of tartar, 5 lbs. of muriate of tin. Enter the goods, boiling 
 for two hours. Remove, cool, and drain over night. Into fresh water stir 
 75 lbs. of good Dutch madder. Enter the fabric at 120 F., and raise the 
 temperature to 200 in one hour. Handle, rinse, and dry. 
 
 Magenta. 
 For 100 lbs. of fabric. Dissolve 8 ozs. of magenta crystals in boiling water 
 and strain through a flannel sieve. Cool the bath to 170 F., in which handle 
 the fabric half an hour. Varying the quantity of magenta crystals will cause 
 variation in the shade. A few lbs. of soap will aid in securing evenness of 
 colour. 
 
 Crimson with Cochineal. 
 
 For 100 lbs. of thibets. Dissolve 10 lbs. of tartar, 6 lbs. of nitrate of tin, and 
 boil the goods in this solution for two hours. Prepare a fresh bath with 20 lbs. 
 of cochineal paste with water at 170° F. ; increase the temperature to 200 . 
 Remove, cool, and rinse. 
 
 Where hard water is employed the colour will be very brilliant ; in the case 
 of river water about 3 lbs. of whiting may be added. For Orleans with 
 Turkey red warps the colouring should be effected in one operation, the paste, 
 tartar, and nitrate of tin being all added at once. Muriate of tin must not 
 be employed. 
 
 Rose-Pink. 
 For 100 lbs. of fabric. Dissolve 5 lbs. of alum, 5 lbs. of cream of tartar, 
 
 2 lbs. of saleratus, 5 lbs. of muriate of tin, with sufficient cochineal paste to pro- 
 duce the required shade. Handle the fabric at 180 F. This colour is faster and 
 better suited for carpetings than that obtained with magenta. 
 

 94 
 
 DYEING AND CALICO PRINTING. 
 
 A 
 
 Dahlia. 
 
 For ioo lbs. of wool. Stir 20 lbs. of good cudbear in a little water, 
 straining through a sieve into a clean kettle. Heat the bath to 180 , and then add 
 2 lbs. of muriate of tin. Enter for one hour without boiling. Rinse and dry. 
 
 Crude acetic acid or wood vinegar can be used to obtain fine red shades of 
 peach colour, and ammonia or pearl-ash for blue shades. Orchil may be 
 substituted for cudbear. This dye should never be boiled. 
 
 Maroon. 
 For 100 lbs. of wool. Boil 20 lbs. of cudbear, or 25 lbs. of orchil, and 4 ozs. 
 of magenta crystals for ten mintes. Cool the dye to 175 F. Enter the 
 fabric or wool, increase the temperature to 212 . Remove, rinse, and dry. 
 
 YELLOWS. 
 Yellow. 
 
 For 100 lbs. of wool. Dissolve 15 lbs. of alum, 4 lbs. of cream of tartar, 
 10 lbs. of muriate of tin, 1 lb. of tin crystals, 2 lbs. of fiavine, or 8 lbs. of quer- 
 citron bark. Boil until the fiavine is dissolved, and cool to 170 F. Enter the 
 wool, and while handling raise the temperature to 212 , then allowing the 
 goods to remain for three quarters of an hour. Remove, cool, and rinse. 
 Cochineal may be added for dark yellows, omitting the alum if the colour 
 approaches orange, as it causes this colour to become dull and blurred. A few 
 pounds of sulphuric acid will sometimes increase the brilliancy of the yellow. 
 Picric acid is employed for delicate tints of yellow, and may be made fast by 
 muriate of tin. 
 
 Balge Yellow. 
 
 This colour is generally employed on cassimere for vestings. The goods 
 should be previously well bleached by sulphuring. 
 
 For five pieces of goods each of 10 lbs. weight. Dissolve in water, heated 
 to 140 F., 5 lbs. of alum, 2 lbs. of muriate of tin, and the liquor from 3 lbs. 
 of fustic. The tannic acid should be previously eliminated from the fustic by 
 adding J lb. of glue to the boiling fustic liquor. Handle the goods until the 
 required shade is obtained. 
 
 Orange. 
 
 For 100 lbs. of wool. Boil for ten minutes 5 lbs. of tartar, 3 lbs. of fiavine, 
 5 lbs. of cochineal, 1 ib. of tin crystals, 10 lbs. of muriate of tin. Cool the 
 kettle to 180 F., and enter the wool for ten minutes. Then if even boil for 
 half an hour; if uneven, add 8 lbs. of hydrochloric acid. Rinse and dry. 
 
 Salmon. 
 For 100 lbs. of wool. Boil for ten minutes 10 lbs. of alum, 3 lbs. of tartar, 
 1 oz. of fiavine, 5 ozs. of cochineal, 6 lbs. of muriate of tin, 2 lbs. of hydro- 
 chloric acid. Cool to 180° F. Enter the wool, handle, and boil until even. 
 Cool and rinse. The shade may be varied by adding more or less cochineal 
 or fiavine. 
 
 Salmon with Madder. 
 For 100 lbs. of wool. Dissolve 10 lbs. of alum, 3 lbs. of tartar, 4 lbs. of 
 muriate of tin, 3 lbs. of madder, 4 lbs. of hydrochloric acid. Heat to 170° F., 
 
COLOURS ON WOOLLENS. 95 
 
 and enter the goods for half an hour, during which time increase the tem- 
 perature to 212 . The madder being a fast colour, the wool must be handled 
 quickly at first, because longer boiling will not remove patches. 
 
 GREENS. 
 Green for Broadcloth. 
 For 100 lbs. of wool. Dissolve 15 lbs. of alum, 3 lbs. of tartar, 3 lbs. of 
 muriate of tin, and 20 lbs. of fustic. The fustic should, of course, be first 
 boiled in water, to which the other constituents of the kettle may be added. The 
 wool should be entered, and the dye raised to slow boiling for about one hour. 
 Remove and cool. Prepare with fresh boiling water 30 lbs. of weld as a bath, 
 to which add 3 lbs. of soda. Cool to 180 F., and enter the prepared wool, 
 allowing it to remain for one hour ; but the bath must not be brought to the 
 boil. Remove. The wool is now coloured a fine yellow, and is finished with 
 indigo in the blue vat. 
 
 This mode of colouring is expensive, but the results are good. 
 
 Another Green for Broadcloth. 
 
 For 100 lbs. of wool. Colour well in the blue vat. Dissolve 15 lbs. of 
 alum, 2 lbs. of tartar, 2 lbs. of sulphate of copper, in which bath boil the 
 wool for one hour. Prepare a fresh kettle by boiling 25 lbs. of fustic and 
 8 lbs. of logwood in water. Cool to 180 F., and enter the prepared wool, 
 handling well for ten minutes; then increase the temperature to 212 for half 
 an hour. Remove and cool. The colour may be tested by hand-fulling with 
 strong soap. 
 
 Logwood Green. 
 
 This colour is a common one, better suited to coarse cloth. For 100 lbs. of 
 broadcloth. Boil the cloth for one hour in a solution of 15 lbs. of alum, 3 lbs. 
 of tartar, 2 lbs. of sulphate of copper. Remove and cool. Boil in fresh water 
 for half an hour 15 lbs. of fustic and 10 lbs. of logwood, into which bath, at 
 a temperature of 180°, reel the cloth for one hour, and then expose it to the 
 air. During the airing run off half the liquor, and reduce the temperature to 
 130*. Then add the solution of 2 lbs. of pearl-ash, or of 3 lbs. of soda-ash 
 or 4 pails of urine. Reel the cloth for twenty minutes and wash. If darker 
 shades should be desired, more logwood may be employed. 
 
 Chrome Green. 
 For 100 lbs. of wool. Dissolve 4 lbs. of bichromate of potash, 10 lbs. of 
 alum, and 2 lbs. of tartar in a kettle of fresh water, in which boil the wool 
 for one hour. Remove, cool, and rinse. Prepare an infusion of 20 lbs. of 
 fustic and 10 lbs. of logwood. Cool to 180 , and enter the prepared wool, 
 boiling for half an hour. Cool, and rinse. This colour darkens in drying and^ 
 finishing, and is not very durable. 
 
 Green for Yarn. 
 For 100 lbs. of yarn. Dissolve by boiling 20 lbs. of alum, 8 lbs. of sulphuric 
 acid, 3 lbs. of extract of indigo, 1 lb. of picric acid. Cool to 180 F., and enter 
 the yarn, bringing the bath, after quickly handling the wool, to a boil. The 
 
9 6 
 
 DYEING AND CALICO PRINTING. 
 
 addition of a few pounds of common salt will assist in rendering the colour 
 even, especially if the yarn be spun of new wool. 
 
 Aniline Green. 
 The crystals of aniline green are red-coloured in dry state; the colour is not 
 so brilliant from aniline crystals that have been kept even a short period of 
 time. The dye is, therefore, best prepared immediately before use ; and the 
 following method maybe adopted, as recommended by Dr. Reimann ("Hand- 
 book of Aniline Colours," pp. 77 to 133). 3 lbs. of magenta crystals are mixed 
 with 3 lbs. of sulphuric acid and 1 lb. of water. To this solution, when cold, 
 1 J lbs. of aldehyde are added, and the whole well mixed upon a water-bath until 
 the liquid, when diopped into acidulated water, exhibits a fine blue colour. The 
 solution may then be poured into 8 gallons of boiling water, to which is added 
 the solution of 3 lbs. of hyposulphite of soda. Boil this liquid for a few 
 minutes, and filter through a cotton cloth. A fine green dye passes through 
 the filter as the filtrate, and a dark blue-gray residue remains. Coloured silk 
 with aniline green, when exposed to 300 of dry heat, changes to blue, but 
 coloured wool suffers no change. 
 
 Aniline Green with Picric Acid. 
 
 For 100 lbs. of woollen goods. First colour with aniline blue, as described 
 under Blue. Remove the cloth or yarn, and add 1 lb. of picric acid and 6 lbs. 
 of alum to the dye. When the solution is complete, enter the woollens, boil 
 for twenty minutes, cool, and rinse. This green is not so fast nor so bright as 
 the former. 
 
 Olive-Green. 
 
 This colour is chiefly used for broadcloths. For 100 lbs. of wool. Dip first 
 in the blue vat. Then prepare a kettle by boiling 20 lbs. of fustic and 10 lbs. 
 of logwood ; to the infusion add 10 lbs. of alum, 2 lbs. of tartar, 2 lbs. of sul- 
 phate of copper, 10 lbs. of madder, 10 lbs. of turmeric. Boil for ten minutes, 
 and then cool the dye to 180 F. Enter the blued wool, handling well for ten 
 minutes, and boiling for one hour and a half. The shade may be varied by the 
 addition of more or less logwood or madder. 
 
 OLIVES. 
 Bichrome Olive. 
 For 100 lbs. of wool. Boil the wool for one hour in a kettle in which has 
 been dissolved 2 lbs. of bichromate of potash, 2 lbs. of tartar, and 5 lbs. of 
 alum. Remove, cool, and rinse. Prepare by boiling for ten minutes a kettle 
 of 20 lbs. of fustic, 5 lbs. of logwood, and 20 lbs. of madder. Cool to i8o°F., 
 and enter the prepared wool. After well handling, boil slowly for half an hour, 
 adding a solution of 2 lbs. of sulphate of copper. Cudbear, camwood, or 
 peawood, may be used instead of madder. Turmeric is too fugitive to be 
 employed with chrome colours. 
 
 A Cheap Olive. 
 For 100 lbs. of wool. Boil for one hour 30 lbs. of fustic, 6 lbs. of logwood, 
 and then add 10 lbs. of sumach, 5 lbs. of madder, 10 lbs. of red sanders, and 
 
COLOURS ON WOOLLENS. 
 
 97 
 
 3 lbs. of tartar, boiling for ten minutes. Cool to 180 F., and enter the wool, 
 boiling for one hour. Then add a solution of 2 lbs. of sulphate of copper, 
 again boiling slowly for half an hour. Darken with 5 lbs. of copperas. When 
 the wool has become even, cool the dye and add two pails of urine. 
 
 Olive on Zephyr. 
 For 100 lbs. of yarn. First boil the yarn for one hour in a solution of 
 20 lbs. of alum, 5 lbs. of tartar, and 2 lbs. of sulphate of copper. Various 
 shades may be obtained upon the prepared wool with fustic, turmeric, orchil, 
 extract of indigo, and picric acid. 
 
 BROWNS. 
 Chrome Brown. 
 For 100 lbs. of fabric. Boil for one hour in a bath of 2 lbs. of bichromate 
 of potash and 5 lbs. of tartar. Then prepare a fresh kettle with 10 lbs. of 
 peachwood, 1 lb. of logwood, and 1 lb. of tartar, boiling for ten minutes. 
 Cool to 175 F., entering and boiling the fabric for half an hour. The above 
 proportion of tartar and chrome should be stridtly adhered to, in order that 
 the colour may become even. 
 
 Chrome Red-Brown. 
 
 Prepare as for chrome brown. Then produce the desired shade by means 
 of fustic or picric acid. Evenness can be attained by employing sufficient 
 tartar. 
 
 Camwood Brown. 
 
 For 100 lbs. of wool. Boil until thoroughly incorporated 100 lbs. of cam- 
 wood, 20 lbs. of sumach, 5 lbs. of logwood, and 2 lbs. of tartar. Cool to 
 190 F., boiling the wool, after careful handling, for one hour. Add a solution 
 of 2 lbs. of sulphate of copper, again boiling for half an hour. Darken with 
 a solution of 6 lbs. of copperas ; and, to obtain a deeper shade, add 3 pails of 
 urine. Remove and cool quickly. 
 
 Fast Brown. 
 For 100 lbs. of wool. Boil for a few minutes 15 lbs. of camwood, 30 lbs. 
 of madder, 10 lbs. of fustic, 15 lbs. of sumach, 5 lbs. of logwood, and 2 lbs. 
 of tartar. Cool, and enter the wool, boiling for one hour, adding afterwards 
 
 2 lbs. of sulphate of copper. Darken with 6 lbs. of copperas, and deepen with 
 
 3 pails of urine, or with soda. 
 
 Another fast brown, but more expensive than the former, may be coloured 
 by the following method. For 100 lbs. of wool : — Dissolve 20 lbs. of alum, 
 3 lbs. of tartar, and 6 lbs. of muriate of tin, and boil the wool for ten minutes 
 in the solution, allowing it to remain over night. To a kettle of fresh water 
 at 140° F., add 100 lbs. of madder ; and handle the wool in this bath for one 
 hour and a half, boiling for twenty minutes. Remove, cool, and rinse, finishing 
 to the required shade in the blue vat. 
 
 Light Brown. 
 For 100 lbs. of wool. Boil 15 lbs. of fustic, 10 lbs. of madder, 12 lbs. of 
 camwood, 2 lbs. of tartar for ten minutes. Cool to 180 , and enter the wool, 
 
 H 
 
DYEING AND CALICO PRINTING. 
 
 handling well. Boil for one hour; and add ij lbs. of sulphate of copper. Boil 
 again for twenty minutes ; and darken with 2 lbs. of copperas. 
 
 Browns on wool should never contain an excess of chrome or peachwood. 
 
 Bismarck. 
 For 50 lbs. of fabric. Dissolve 10 lbs. of alum, 2 lbs. of sulphuric acid, 
 2 ozs. extract of indigo, 1 oz. of fustic, 3 ozs. of madder. Cool and enter 
 the fabric. Boil for half an hour. Remove, cool, and rinse. Pass the fabric 
 next through a cold bath of 3 lbs. of peachwood, 5 lbs. of fustic, and \ lb. of 
 logwood, with 8 lbs. of dissolved alum. Cudbear, orchil, or magenta and 
 picric acid may be substituted for the madder, sometimes with the advantage 
 of greater evenness of colour. 
 
 Aniline Bismarck. 
 
 For 50 lbs. of part cotton fabric. Dissolve ij ozs. of aniline brown in 
 boiling alcohol. Enter the goods at 170 F., and handle until even ; then 
 colour the cotton as for cotton warps. A bath of strong alum water, sulphuric 
 acid, cudbear, indigo-extract, fustic, or picric acid will yield a good Bismarck 
 with mousselines or thibets. 
 
 On zephyr, Bismarck of any desired shade may be obtained according to 
 the following method, by varying the strength of the red, blue, and yellow 
 dye materials: — For 100 lbs. of yarn. Boil the yarn for one hour in a bath cf 
 20 lbs. of alum and 5 lbs. of crude tartar. Add a small quantity of sulphuric 
 acid, cudbear, fustic, or picric acid, and indigo-extract ; J lb. of cudbear, 5 lbs. 
 of fustic, and i oz.-of indigo-extract are in good proportion. 
 
 Mode with Indigo Bottom. 
 For 100 lbs. of wool. Colour lightly with indigo-blue. Prepare a beck at 
 180° F., with 2 lbs. of tartar, 15 lbs. of fustic, 6 lbs. of cudbear, and 8 lbs. of 
 madder. Enter the wool and boil for one hour. Darken with copperas, or 
 deepen with sulphate of copper. 
 
 Mode without Indigo. 
 For 100 lbs. of wool. Prepare a bath with 2 lbs. of tartar, 5 lbs. of sumach, 
 1 lb. of logwood, 4 lbs. of fustic, 2 lbs. of cudbear, and 5 lbs. of madder. 
 Enter the wool at 180 F., boiling slowly for one hour. Darken with 2 lbs. 
 of copperas, boiling for twenty minutes. Remove and evpnse to the air; cool 
 for half an hour and rinse. Smaller quantities of dye-stuff in the same pro- 
 portion to each other will yield lighter colours. 
 
 DRABS AND SLATES. 
 
 Drab. 
 
 For 100 lbs. of wool. Dissolve 2 lbs. of tartar, 5 lbs. of camwood, 3 lbs. 
 
 of sumach, 3 lbs. of fustic, and 1 lb. of logwood. Enter the wool at 180 F., 
 
 boiling for one hour. Then add 3 lbs. of copperas in solution, and again boil 
 
 for twenty minutes. Cool, expose to the air, and rinse. 
 
 Another drab maybe obtained with a bath of 2 lbs. of tartar, 1 lb. of madder, 
 1 lb. of camwood, 1 lb. of cudbear, 1 lb. of fustic, 1 lb. of logwood, and 1 lb. 
 of sumach. Proceed to darken, air, and rinse as before. 
 
COLOURS ON WOOLLENS. 
 Slate. 
 
 99 
 
 For ioo lbs. of wool. Prepare a bath with 2 lbs. of tartar, 2 lbs. of sumach, 
 3 lbs. of logwood, and 2 lbs. of cudbear. Enter the wool at 180 F., and boil 
 slowly for one hour. Darken with a solution of 3 lbs. of copperas. After 
 twenty minutes remove, air, and rinse. 
 
 Purple Slate. 
 For 100 lbs. of wool. Prepare a bath with 2 lbs. of tartar, 3 lbs. of sumach, 
 ij lbs. of logwood, and a hot alcoholic solution of 2 ozs. of aniline purple. 
 Enter the wool at 180 F., and boil slowly for one hour. Darken with 2 lbs. 
 of copperas. Handle, cool, rinse, and dry. 
 
 Stone Colour. 
 For 100 lbs. of wool. Prepare a bath with 2 lbs. of tartar, 4 lbs. of sumach, 
 1 lb. of logwood, 5 lbs. of fustic, and 2 lbs. of madder. Boil the wool slowly 
 for one hour; darken with 3 lbs. of copperas. 
 
 Silver Grey. 
 For 100 lbs. of wool. Prepare a bath with 1 lb. of crude tartar, \ lb. of 
 nut-galls, * lb. of cudbear, and $ lb. of logwood. Enter the wool at 180 F., 
 handling well. Then increase the temperature to 200 F. for one hour; cool 
 and darken with copperas. When even, remove, air, and rinse. 
 
 Lavender. 
 For 50 lbs. of fabric (thibets or zephyr). Prepare a bath, at a temperature 
 of 180°, with 5 lbs. of alum, 5 lbs. of cream of tartar, 6 ozs. of indigo-extract, 
 6 ozs. of cochineal paste. Enter the cloth and boil until even. If the 
 thibets are of mixed silk, the silk will remain uncoloured ; it may be dyed red 
 by substituting cudbear or orchil for the cochineal paste; or the wool may be 
 coloured mode and the silk a golden yellow by employing cudbear and 
 turmeric instead of fustic and cochineal. Sulphuric acid instead of tartar, 
 cudbear or orchil instead of cochineal paste, are more economical in the case 
 of coarser goods without silk. 
 
 PURPLES. 
 Aniline Purple. 
 For 100 lbs. of wool. Dissolve 12 ozs. of Perkin's purple in 1 quart of hot 
 alcohol, straining the solution through a flannel sieve. Add 4 lbs. of acetic 
 acid, 4 lbs. of alum, and 1 lb. of tartar. Enter the wool at 175 F., and after 
 handling, bring the bath to a boil for one hour. Should a blue shade be 
 desired, add 3 lbs. of diluted sulphuric acid; if a red shade, the following 
 method is to be preferred :— 12 ozs. of Perkin's purple, dissolved and strained 
 as before (Hofmann's purple docs not require alcohol). Add separately 2 ozs. 
 of magenta and 4 lbs. of acetic acid. Enter at 170 F., handling quickly at 
 first. 
 
 BLACKS. 
 
 Chrome Black. 
 For 100 lbs. of wool or fabric. Dissolve i\ lbs. of bichromate of potash 
 and 2 lbs. of argol. Boil the fabric or wool in this solution for one hour. 
 Cool and rinse. 
 
DYEING AND CALICO PRINTING. 
 
 Boil in fresh water 25 lbs. of logwood and 10 lbs of fustic, adding $ lb. of 
 argol, J lb. dilute sulphuric acid. Enter the prepared wool. Boil for three 
 quarters of an hour. Remove, cool, and rinse. For Orleans and lastings with 
 coloured warps the sulphuric acid must be omitted. A blue-black may be 
 obtained by omitting the fustic and some of the logwood. 
 
 Sumach Black. 
 For 100 lbs. of cloth. Dissolve 40 lbs. of sumach and 2 lbs. of argol. 
 Enter the fabric, boiling slowly for one hour. Remove the fabric, and add to 
 the beck 6 lbs. of copperas and 2 lbs. of sulphate of copper. Enter at 190 F. 
 for half an hour. Remove and air. Cool the dye to 150 F., and add a 
 solution of 4 lbs. of soda-ash. Run through for fifteen minutes, remove, and 
 rinse. This dye upon broadcloth will take colours from the printing block, 
 and may be discharged during steaming if oxalic acid is mixed with the colours. 
 
 Fast Black. 
 This colour prepared without iron, copper, chrome, or logwood is not suited 
 to common goods, but is adapted for application to mixed goods, such as 
 hosiery. Colour the fabric with lac-scarlet. Then pass it through a warm 
 bath of weak soda-lye (about 5 lbs. of soda). Rinse, and finish in the indigo- 
 vat until black — 6 lbs. of indigo to 100 lbs. of fabric. 
 
 Cheap Black. 
 For 100 lbs. of cloth. Boil in a bag for half an hour 25 lbs. of logwood 
 and 10 lbs. of fustic, and to the bath add 3 lbs. of blue vitriol, 1 lb. of tartar, 
 and J lb. of hydrochloric acid. Enter the cloth, boil for one hour, and then 
 pass through a warm solution of 5 lbs. of soda. The dye is very fugitive. 
 
 Black for Silk-striped Thibets. 
 For 5 pieces of fabric, each piece weighing 10 lbs. Dissolve 5 lbs. of 
 copperas, 1 lb. of sulphate of copper, 2 lbs. of tartar, ij ozs. of chloride of 
 tin crystals, or 3 ozs. of oxychloride of tin.* Enter the fabric over a reel, and 
 boil for one and a half hours. Remove, cool, and rinse. Prepare a fresh bath 
 with 25 lbs. of logwood. Cool to 180° F., and enter the prepared goods, 
 handling them quickly. Cool to 130 , adding 2 lbs. of liquor ammonia. After 
 fifteen minutes rinse and dry. 
 
 COLOURS ON WOOL AND WARPS. 
 Slates and Modes on White Warps. 
 For 15 pieces of goods, each piece weighing 10 lbs. Dissolve 20 lbs. of 
 alum, 15 lbs. of sulphuric acid, 2 lbs. of extradt of indigo, 6 lbs. of cudbear, 
 1 oz. of aniline purple dissolved in hot alcohol. Cool to 180 F M and enter 
 the fabric, reeling for one hour, and raising the temperature to boiling. 
 Remove and rinse. Then reel through a cold bath of 50 lbs. of sumach for 
 half an hour, and afterwards through a cold bath containing a solution of 
 10 lbs. of copperas, 2 lbs. of sulphate of copper, and 2 lbs. of nitrate of iron. 
 Remove and rinse. 
 
 * Obtained by passing chlorine through a solution of muriate of tin. 
 
COLOURS ON WOOL AND WARPS. 101 
 
 Magenta on Cotton Warps. 
 For 50 lbs. of fabric. First colour with the magenta as for wool. Then 
 take the fabric through a cold bath of 2 lbs. of nut-galls, handling for twenty 
 minutes. Dissolve i£ ozs. of magenta crystals, adding the solution to a cold 
 bath. Enter the goods fresh from the nut-galls ; handle for half an hour. 
 Rinse and dry. 
 
 Purple on Cotton Warps. 
 For 50 lbs. of fabric. Colour first a light purple, and then pass through a bath 
 containing 2 lbs. of nut-galls. Dissolve 2 ozs. of aniline purple in alcohol, 
 and with it prepare a cold bath. Enter the goods. Reel quickly at first, 
 then slowly for half an hour. 
 
 Scarlet on Cotton Warps. 
 For 50 lbs. of fabric. Colour first scarlet as for wool. Then pass through 
 a cold bath containing a large quantity of sumach for half an hour, and after- 
 wards through a solution of 8 lbs. of nitrate of tin. Have the mordant as 
 little diluted as possible, and handle for ten minutes. Then take the fabric 
 through a cold bath of 8 lbs. of alum and 5 pails of fustic liquor, to which 
 add 1 lb. of whiting or chalk. Afterwards pass through a cold bath con- 
 taining 25 lbs. of peachwood. 
 
 Saxon Blue on Cotton Warps. 
 For 50 lbs. of fabric. Colour first as for wool. Then handle for fifteen 
 minutes in a cold bath containing 3 lbs. of nitrate of iron and 2 lbs. of muriate 
 of tin. In a fresh kettle dissolve 1 lb. of yellow prussiate of potash, to which 
 add 2 lbs. of sulphuric acid. Enter cold, and pass again through the mordant. 
 Rinse and dry. 
 
 Aniline Blue on Cotton Warps. 
 For 50 lbs. of fabric. Colour first as for wool. Then colour the cotton 
 with the prussiate of potash and the nitrate of iron alternately until the 
 desired shade is obtained. 
 
 Black and Orange on Cotton Warps. 
 For 50 lbs. of black wool with white warps. Run 10 lbs. of the cloth at a 
 time through a cold beck of 10 lbs. of acetate of lead, previously boiled for 
 twenty minutes with 5 lbs. of litharge. Thence take each 10 lbs. through a 
 cold weak lime bath, and again through a warm bath containing 10 lbs. of 
 bichromate of potash. Again through weak lime water. In colouring orange 
 on cotton, it should always be borne in mind that the fabric should not be 
 taken directly from the lead beck into the chrome in order to prevent the 
 occurrence of bleared stripes. 
 
 Green on White Warps. 
 For 50 lbs. of fabric. First colour the wool green as for yarn. Then colour 
 the warp with Saxony blue, passing the blued fabric through a beck containing 
 10 lbs. of alum and 10 lbs. of fustic liquor. For an intensely yellow shade 
 citron bark or turmeric may be added. 
 
DYEING AND CALICO PRINTING. 
 
 RANDOMS, OR CLOUDED YARNS. 
 On the large scale the random yarns are coloured in machines, but the 
 following method can be recommended for colouring in the ordinary manner : — 
 The yarn is first scoured with soap and bleached, and 15 to 20 lbs. are parted 
 off into handfuls of about 1 lb. of yarn each. The yarn thus mechanically 
 prepared is laid in a bath of water, slightly acidified with muriate of tin to 
 neutralise the small quantity of alkali still remaining in the yarn. 
 
 Scarlet Random. 
 
 A kettle should be prepared of the following dimensions : — 5 feet in length, 
 2 feet 2 inches in width, and 7 inches in depth, made of copper thickly tinned. 
 The bath may be heated by steam or by fire. The kettle should be filled with 
 water to within 2 inches of the rim, and the water raised to a boil. Then 
 add 1 1 lbs. of ground cochineal, 2 ozs. of flavine, \ lb. of tartar, 3 lbs. of 
 scarlet spirit (muriate of tin), and 2 ozs. of tin crystals. Boil for five minutes, 
 then remove the source of heat. The height of the liquid in the kettle should 
 be adjusted to the depth of dye required upon the yarn ; if the level of the 
 dye is low there will be much white and little scarlet ; if high, much scarlet 
 and little white. 
 
 The yarn must now be hung upon sticks in the following manner : — The 
 kettle being 26 inches' wide, the sticks to bear fairly on the rim should be at 
 least 30 inches long, | inch broad, and £ inch thick. Taking two sticks in 
 his right hand and one handful of the soaked yarn in his left, the dyer hangs 
 it upon the sticks skein by skein; he then grasps one of the sticks in the 
 middle of its length, and allows the other to remain supported by the yarn. 
 The upper stick is then placed against two pegs 2\ inches from another pair 
 of pegs, each peg of the pair being 26 inches from the other. The yarn being 
 drawn from the upper stick, a second stick is laid on the nearer side of the 
 nearer pair of pegs, the yarn being then carried back to the more distant 
 pair of pegs, and there secured by another stick. The yarn thus folded 
 backward and forward is thoroughly wetted with cold water, and is then 
 immersed in the kettle. All the contents of the sticks may be handled at one 
 time by means of a pole passed under the whole series of sticks. After twenty 
 minutes the yarn will be a good scarlet, and may be taken out and rinsed. 
 The rinsing water should be allowed to flow down upon the yarn, so that the 
 dye may not be carried on to the whites. By this method one man can 
 colour 150 lbs. of yarn daily without assistance. 
 
 Orange Random. 
 The yarn should be soured as for scarlet. The kettle is prepared with J lb. 
 of flavine, £ lb. of tartar, 2 lbs. of muriate of tin, 2 ozs. of tin crystals, 6 ozs. 
 of cochineal, and the bath is raised to the boiling-point for ten minutes before 
 the wet yarn is entered. In twenty minutes remove and rinse. 
 
 Saxon Blue Random. 
 Prepare the kettle with 6 ozs. of extract of indigo, 2 lbs. of alum, 1 lb. of 
 sulphuric acid, and $ lb. of muriate of tin. Raise the temperature to 190° F., 
 and then remove the source of heat. Enter the wet yarn. The yarn may be 
 bleached after colouring, being well rinsed after removal from the sulphur- 
 house. 
 
RANDOMS, OR CLOUDED YARNS. 
 
 103 
 
 Prussian Blue Random. 
 The yarn must be unbleached. Soak the yarn in the dilute muriate of tin 
 bath; and prepare the kettle with £ lb. red prussiate of potash (to every 15 lbs. 
 of yarn), adding J lb. of sulphuric acid and 1 lb. of muriate of tin. Heat to 
 120 F., and enter the yarn, raising the bath to the boiling-point in the course 
 of an hour. Remove, cool, and expose to the oxygen of the atmosphere for 
 several hours ; then rinse. Should the yarn show green spots a few minutes' 
 steaming will remedy the defect. 
 
 Magenta Random. 
 Half an ounce of magenta crystals (to 20 lbs. of unbleached yarn) dissolved 
 in a bath heated to 170 F. Treat as for Saxon blue; rinse quickly, and 
 bleach in the sulphur-house. Rinse again in cold water. 
 
 Purple Random. 
 For 20 lbs. of yarn. Soak the yarn in water acidified with sulphuric acid 
 (1 lb. of acid to 6 pails of water). Then enter it in a bath containing i oz. of 
 aniline purple dissolved in hot alcohol, to which is added 1 lb. of acetic acid. 
 Heat to 160 F., and enter the yarn in one lot. The yarn should be bleached 
 after colouring. 
 
(io4: 
 
 CHAPTER XIII. 
 
 OILK is valued on account of its high gloss, its fineness and great strength^ 
 *-' and the beautiful colours it assumes in the dye-beck. It is the produce 
 of an insect, or rather the larva of an insect known as Bombyx or Phaltena inori. 
 The insect, and the tree upon the leaves of which it feeds, are natives of 
 China, where, according to the historical accounts, silk-worms have been 
 reared, and silk woven into tissues since the year 2698 B.C. From China the 
 cultivation of the mulberry tree and the rearing of silk-worms became intro- 
 duced into Persia and Hindostan ; while sericiculture has been but more 
 recently known to Europeans. In France the mulberry tree and the worm 
 were first cultivated about 1494. 
 
 Silk, like the web of the spider, is a secreted substance, that is, it is ejected 
 in a liquid state from the body of the insect, and solidifies immediately on 
 contact with the air. The spun fibre averages in length 350 metres ; its 
 diameter never exceeds -, Jg c ths of a millimetre. Viewed under the microscope 
 it has a somewhat flattened cylindrical appearance. Every fibre consists of 
 two distinct parts, an external envelope and an interior textile fibre or true 
 fibroi'ne. The external layer consists of a mixture of albumenoid, nitrogenous, 
 and fatty-resinous matters, to which is sometimes added a colouring matter. 
 
 With the exception of MM. Roard and G. J. Mulder, no scientific man has 
 attempted the investigation of the constitution of silk. M. Roard extracted 
 by means of alcohol from raw silk — (1) a wax-like substance similar 
 to the cerotic acid, Czyl^O^, of bees'-wax ; (2) when raw yellow silk 
 was experimented upon, a colouring-matter incorporated with a brown-red 
 resinous substance was found. According to M. Mulder, the latter can 
 be separated by repeatedly washing with an aqueous solution of caustic 
 potash. White, as well as yellow, silk, when raw, yields upon treatment 
 with boiling water a nitrogenous matter, which in its character and 
 composition bears a close relation to gelatine, and, according to M. Mulder's 
 researches, is identical therewith. When raw silk has been treated 
 consecutively with water, alcohol, and ether, it yields on treatment with 
 concentrated and boiling acetic acid two different nitrogenised substances, 
 one of which being soluble in the acid behaves with reagents similarly 
 to a solution of albumen in acetic acid, while its percentage com- 
 position is that of albumen, although it differs in some respects from the 
 white of eggs. The other nitrogenised substance is insoluble, and consists of 
 pure fibroi'ne. Silk therefore contains in raw state — (1) cerotic acid ; (2) a red 
 colouring-matter, not met with in white silk; (3) fatty substances; (4) resinous 
 matter; (5) a nitrogenised substance soluble in boiling water or gelatine; 
 (6) a nitrogenised substance insoluble in boiling water, but soluble in boiling 
 concentrated acetic acid ; (7) and finally, fibroi'ne. 
 
SILK. 105 
 
 An analysis of silk, by M. Mulder, gave for 100 parts: — 
 
 Yellow Naples White Silk from the 
 Silk. Levant. 
 
 Fibroine 5337 54-04 
 
 Gelatine 20-66 19-08 
 
 Albumen 24-43 2 5'47 
 
 Wax 139 in 
 
 Colouring-matter 0-05 — 
 
 Fatty and resinous matters .. o-io 0-30 
 
 Fibroine has the appearance of silk, but is softer, more flexible, and not so 
 strong. Heated on platinum foil it swells up, and, bursting into flame, burns, 
 leaving a voluminous coke, which emits a peculiar odour. It is insoluble in 
 neutral solvents and in acetic acid. Fibroine, as well as silk, is soluble in an 
 ammoniacal solution of oxide of copper, Schweitzer's reagent ; neither are 
 acted upon by a solution of oxide of copper in carbonate of ammonia. A 
 solution of silk or fibroine in Schweitzer's reagent is not precipitated either 
 by salts, sugar, or gum, as in the case of a solution of cotton in the same reagent. 
 Dilute acids precipitate a flocculent mass from the solution of silk. According 
 to M. Schlossberger, an ammoniacal solution of oxide of nickel behaves 
 with silk similarly to Schweitzer's reagent, but does not act at all upon cotton. 
 The fibroine of sponge is not acted upon by an ammoniacal solution of either 
 nickel or copper. A solution of basic chloride of zinc at 6o° Baume 
 dissolves in the cold, and more rapidly when aided by heat, a considerable 
 quantity of silk, forming a viscous, syrupy solution, which, acidulated and 
 then submitted to dialysis, attains the consistency of a thick starch paste ; 
 when a more dilute solution is submitted to dialysis, a liquid is obtained 
 which, on being evaporated to dryness, yields a golden-coloured varnish, 
 and this varnish raised to a temperature approaching incipient red-heat 
 assumes, immediately before its decomposition, a beautiful groseille red 
 tinge. When silk is acted upon in the cold by strong sulphuric acid, it yields 
 a viscous bright brown-coloured solution, which turns red, and becomes 
 coloured a deep brown when heat is applied. Water does not precipitate the 
 solution, but the solution thus diluted is precipitated by tannic acid. Nitric 
 and hydrochloric acids also readily dissolve silk at the ordinary temperature, 
 and alkalies precipitate the solution. When silk is acted upon by nitric acid 
 and heat applied, it is converted into oxalic acid. Although silk is not 
 dissolved by dilute solutions of caustic alkalies, these should not be applied 
 to silk for any purpose, because they cause deterioration of the fibre, removing 
 the gloss and brilliancy. Concentrated solutions of caustic alkalies dissolve silk 
 and fibroine, and the solution is precipitated by water and dilute sulphuric acid, 
 but the precipitate obtained is altered in composition. When fibroine is heated 
 with caustic potash it is converted into oxalic acid. The alkaline carbonates 
 and ammonia do not dissolve silk ; and ammonia may be advantageously 
 employed in the cleansing of silk, especially if diluted with both water and 
 pure spirits of wine. Many shades of dyed silk will not, of course, withstand 
 this treatment. Fibroine does not contain sulphur, and the two nitrogenised 
 substances which accompany fibroine are also free from sulphur. Fibroine 
 yields 03 per cent of ash composed of sulphates, chlorides, alkaline phosphates, 
 phosphate of lime, and magnesia, oxides of iron, manganese, and alumina. 
 

 DYEING AND CALICO PRINTING. 
 
 Bleaching Silk. 
 Silk as obtained from the cocoon is unfit for use, even when it is desired that 
 it should be woven into those extremely fine tissues known as silk gauze, 
 which is made of raw silk thread. For this purpose it is necessary that the 
 raw silk from the cocoon should be submitted to some mechanical operation 
 by which a number of the fibres may become united or spun together. But 
 our province is not to treat of the processes of spinning; we shall therefore 
 proceed to the means of removing the colouring-matter from the raw silk, as well 
 as the gummy matter and wax. The oldest process in use for this purpose is 
 boiling with soap, and is the only one which can be advantageously as well as 
 safely employed. Raw silk loses during this process 25 to 30 per cent of its 
 weight. At the first boiling the quantity of soap taken is 30 per cent of the 
 weight of the silk ; a second boiling is effected with 15 per cent of soap. 
 Great care is required in the management of these operations, as experience 
 has proved that the silks from Piedmont, the Cevennes, and Bengal cannot 
 withstand a prolonged a&ion even of soap without becoming very seriously 
 weakened in strength. 
 
 Sometimes silk is treated with a weak alkaline bath composed of 12 per cent 
 of the weight of the silk of caustic soda ; but although by this operation silk 
 loses only 12 per cent in weight it becomes very dull and the fibre brittle. 
 Another method of treating silk is to immerse it for a few minutes in a bath 
 composed of 1 part of nitric acid, 4 parts of hydrochloric acid, and sufficient 
 water to obtain at a temperature of 30 to 35 a liquid of a density of 15 to 
 18 Baume. The silk is immersed in this liquid after having been steeped in 
 a tepid soap bath containing 10 per cent of soap. As soon as the silk placed 
 in the acid bath assumes a grey tinge it should be removed, washed thoroughly 
 in a large quantity of cold water, and next submitted to the action of the 
 fumes of burning sulphur. In order to augment the whiteness of the bleached 
 silk it is sometimes thought necessary to employ a blue colouring-matter. 
 Baume has introduced the following method for bleaching and softening 
 silk : — The raw silk is steeped in cold water for a few days to dissolve the 
 gelatine contained. It is next placed for thirty-six hours in alcohol, to which 
 pure hydrochloric acid has been added (96 kilos, alcohol of 0*84 sp. gr., 
 and 400 grms. of pure hydrochloric acid). The silk is afterwards washed in 
 cold water and dried. This method is, however, too expensive for use on the 
 large scale, but the results are excellent. As regards the water to be employed 
 in the bleaching of silk, the purest and the freest from lime is the best ; the 
 quality of the water is, in France, considered of so much importance that the 
 silk is sent to localities, especially in the Department de l'Ardeche, where the 
 water, owing to the prevalence of granite rock, is almost entirely free from 
 lime salts. Silk is very readily injured by the insoluble lime soap which is 
 formed when soap is dissolved in water containing soluble salts of lime, its 
 softness, strength of fibre, and colour being impaired. 
 
 The loss of 25 per cent in weight of so valuable a substance as silk has had 
 the effect of turning the attention of many to the devising of processes for 
 removing the colouring-matter without taking away the gummy substance 
 and the wax which contribute to so large a portion of the loss, but the attempt 
 is futile on the ground that silk cannot be dyed, or at least not uniformly dyed, 
 unless the whole of the gelatine, wax, resinous, and colouring-matters are 
 
SILK AND OTHER FIBRES. 
 
 107 
 
 removed. Baume's process leaves in the silk all the albumen ; the gelatine, 
 wax, and resinous matters only are dissolved, reducing considerably the per- 
 centage of loss. It is stated that the Japanese and Chinese have practical 
 processes for bleaching silk without the use of soap or great loss in weight, 
 but there is no definite information extant. 
 
 Means of Distinguishing Silk and Other Fibres. 
 
 It is not at all difficult to distinguish wool from silk when attention is paid 
 to the several solvents. There may be added to the information given undjr 
 the preceding heading the statement of the fad: that pure quadrihydratcd 
 nitric acid, while it dissolves silk, only colours wool yellow. Wool, owing to 
 the sulphur it contains, becomes coloured black in a solution of oxide of lead 
 in caustic potash. Nitro-prusside of sodium is a more delicate reagent, the 
 wool or silk having been dissolved in a caustic alkali. Silk and wool are 
 dissolved in caustic alkalies when heat is applied ; cotton and linen fibres 
 are not affected by similar treatment. Animal fibres emit on combustion the 
 peculiar odour of burnt feathers, become coloured yellow with nitric acid, and 
 red with nitrate of mercury, and are not acted upon during steaming after 
 having been moistened with dilute mineral acids. Cotton, hemp, and flax 
 fibres burn without emitting the peculiar odour, and are strongly attacked 
 during steaming when previously moistened with even very dilute mineral acids. 
 
 The microscope, however, affords the most ready method of distinguishing 
 fibres from each other. The fibre of cotton, Fig. 7, appears as a riband 
 twisted spirally, and its characteristics are unmistakable. Flax fibre, Fig. 8, 
 is neither stiff nor twisted, and is distinguished by the narrowness of its 
 inner tube. The fibre of silk, Fig. 10, is perfectly cylindrical throughout, not 
 hollow inside, and the surface is smooth and glossy, whilst woollen fibres, 
 Fig. g, are scaled and bark-like in appearance. Fig. 11 represents woollen, 
 cotton, and silk fibres as they appear together under the object-glass of a 
 microscope magnifying 120 to 150 times. The sample of cloth to be sub- 
 mitted to examination should be cut up, placed on a slide in water, and covered 
 with a thin piece of glass. Other fibres may be distinguished readily by means 
 of the microscope ; and for this purpose the following observations will be 
 found of use : — 
 
 Manilla. — Fibrous bundles oval, nearly opaque, and surrounded by a con- 
 siderable quantity of dried up cellular tissue, composed of rectangular cells. 
 The bundles are smooth ; very few partly detached ultimate fibres are seen, 
 and no spiral tissue. 
 
 Sizal. — Fibrous bundles oval and surrounded by cellular tissue. Smooth 
 and very few ultimate fibres projecting from the bundles. More translucent 
 than Manilla, and always to be recognised by the large quantity of spiral 
 fibres mixed up in the bundles. 
 
 New Zealand Flax, or Phurmium Tenax. — In machine-dressed Phormium 
 the bundles are translucent and irregularly covered with tissue. Spiral 
 fibres can be detected amongst the bundles, but not in the same quantity 
 as seen in Sizal. Many more ultimate fibres project from the bundles, which 
 are flat instead of oval. In those places where the bundles are entirely 
 freed from tissue they are generally divided longitudinally into two or 
 more smaller bundles or fasciculi, and in these places the number of half- 
 
DYEING AND CALICO PRINTING. 
 
 
 detached ultimate fibres is greatly increased ; they are, however, rarely 
 broken, most of them having the end perfect. Spiral fibres are here absent. 
 In Maori-prepared Phormium the bundles are almost entirely free from 
 
 Fig. 7. 
 
 tissue, and quite so from spiral fibres. These are always broken up into 
 many fasciculi, which average, perhaps, some twelve or fifteen ultimate fibres 
 in each fasciculus. Many ultimate fibres are semi-detached, and they are 
 
 Fig. 8. 
 
 Fig. 9. 
 
 
 much more broken than in machine-prepared fibre. For examination of the 
 ultimate fibre, Captain Hutton recommends boiling for two or three hours in 
 a weak solution of potash, and separation of the fibres by dissection under the 
 
SILK AND OTHER FIBRES. 
 
 109 
 
 microscope in water. The ultimate fibres of Sizal will be found to separate 
 easily, those of Phormium with more difficulty, while it will require great care 
 to prevent breaking those of Manilla ; this latter fibre will require a much 
 longer boiling to render separation easy. According to Captain Hutton's table 
 
 Fig. ri. 
 
 Fig. 10. 
 
 w 
 
 of measurements, the average length of the fibre of Phormium will be found 
 to be nearly twice that of the others ; while the average diameter is not more 
 than half that of Manilla, which is again much less than that of Sizal. The 
 cell wall of Phormium is also much thinner than that of either of the other 
 two. 
 
(no) 
 
 CHAPTER XIV. 
 
 POTASH, SODA, AND LIME SALTS. 
 
 POTASH. 
 "D OTASH, according to the commercial term, but chemically carbonate of 
 potash, KO,C0 2 , occurs in the inorganic and in the organic kingdoms. 
 In the inorganic state its compounds are found in feldspar, in deposits with 
 rock salt, the mother-lye of saline springs, and in sea-water. But the organic 
 sources are also very important, and include the ash of plants, and the ash of 
 other organic substances. Potash is obtained by elutriation of the ashes 
 of plants, the evaporation of the lye, and the calcination of the residue; 
 this residue, or commercial carbonate of potash, is more or less rich in pure 
 carbonate of potash. The qualities of good potash are that it should be hard, 
 porous, of a white, geen, blue, gray, or red shade, possessing a caustic taste, 
 and the quality of absorbing atmospheric moisture or of deliquescing, being 
 readily soluble in water. The value of potash depends upon the quantity of 
 potash which as carbonate of potash or as caustic potash it contains. The 
 proportion of carbonate of potash can be estimated by various methods 
 giving more or less accurate results. A useful test is the following: — ioo grains 
 of well-dried potash are weighed out and dissolved in a beaker. Into another 
 300 grains of diluted chemically pure sulphuric acid are introduced in the 
 proportion of 100 grains of concentrated sulphuric acid to 200 grains of pure 
 water. The sulphuric acid sets free the carbonic acid of the carbonate, 
 which can be measured by the corresponding loss of weight. Multiplying the 
 number indicating this loss of weight by 100 and dividing by 32 will give the 
 percentage of pure carbonate of potash contained in the sample. It will be 
 necessary, should not the solution of potash be clear, to first filter it, to wash 
 the residue, and to add the wash-water to the filtrate. 
 
 The alkalimetric method is grounded upon the fact that caustic potash and 
 carbonate of potash are converted into sulphate upon the addition of sulphuric 
 acid. 100 parts by weight of anhydrous potash will saturate 104 parts by 
 weight of sulphuric acid of 66° B. It becomes then only necessary to add 
 104 parts by weight of sulphuric acid (66° B.) to 100 c.c. of water in a burette, 
 so that the fluid reaches to 0°. The potash is weighed out in 100 parts, 
 dissolved in water, and the clear solution coloured blue with litmus-solution. 
 The acid is added in small quantities, in order that the mixture may not 
 become much heated. The solution presently acquires a wine-red colour, and 
 the number of c.c. of acid solution required to effect this change will give the 
 percentage of anhydrous potash. The chief impurities of commercial potash 
 are sand, silica, and metallic salts. The sand can in great part be removed 
 by dissolving the potash, and filtering. The silica occurs chiefly as silicate 
 
POTASH SALTS. n x 
 
 of potash. Copper salts can be deteded by dissolving the potash in hydro- 
 chloric acid, supersaturating with ammonia, when, if copper be present, the 
 solution will become coloured blue. 
 
 The potash of the market is generally termed pearl-ash or American ash, or 
 salt of tartar. It is not largely employed in printing or dyeing; chiefly in 
 Turkey-red dyeing for the emulsion of oil, and also as a solvent of annatto 
 and safflower. 
 
 Nitrate of Poatsh. 
 This salt, KO,N0 5 , occurs native as saltpetre; but it finds no application 
 in dyeing or bleaching. 
 
 Bisulphate of Potash. 
 This salt, containing two equivalents of sulphuric acid to one of potash, is 
 sometimes employed as a substitute for tartaric acid in lower styles of work, 
 but requires care, and is uncertain in its application. 
 
 Chromate of Potash. 
 
 There are two chromates of potash known, viz., the chromate, KO,Cr0 3 , 
 and the bichromate, KO,2Cr0 3 . 
 
 Bichromate or acid chromate of potash occurs in commerce in beautiful red 
 crystals, very easily soluble in water, and is employed in the preparation of 
 yellow, red, and green colours. When blue indigo is impregnated with bi- 
 chromate of potash and treated with a solution of tartar, oxalic acid, or diluted 
 sulphuric acid, the chromic acid is set free, and the available oxygen converts 
 the indigo into indigo-white. Isatine can be obtained similarly by treating 
 indigo-blue with permanganate of potash or with ferricyanide of potash and 
 lime. 
 
 The impurities most generally occurring in bichromate of potash are 
 sulphate of potash, chloride of potassium, and nitrate of potash. Sulphate 
 of potash may be detected by treating the bichromate with hydrochloric acid, 
 and adding chloride of barium, when, if any sulphate is present, a white pre- 
 cipitate is formed. Chloride of potassium may be detected by the addition of 
 nitric acid, and precipitation with nitrate of silver. Nitrate of potash causes 
 the salt to detonate when thrown upon a red-hot plate. 
 
 Chromate of potash, or neutral chromate, crystallises in beautiful yellow 
 crystals, easily soluble in water. It can be prepared by adding carbonate of 
 potash to a solution of the bichromate. 
 
 Oxalate of Potash. 
 
 Oxalate of potash occurs in three varieties, viz., as neutral oxalate, as acid 
 oxalate or binoxalate, and as quadroxalate. The oxalate of potash of commerce 
 is prepared by neutralising oxalic acid with carbonate of potash ; and it occurs 
 in white crystals, which may be rendered anhydrous by heat, and then will 
 dissolve in three parts of water. Its chief application is found in printing. 
 
 The impurities are sulphate of potash, tartar, and metallic salts. Sulphate 
 of potash may be detected by dissolving a sample of the salt in warm water, 
 and treating with hydrochloric acid and chloride of barium to obtain a white 
 precipitate. Nitrate of silver will yield a precipitate if chloride of potassium 
 is present, excess of nitric acid having previously been added. Tartar gives 
 
ii2 DYEING AND CALICO PRINTING. 
 
 a peculiar odour when the salt is submitted to combustion, and leaves a gray 
 or black residue. Most metallic salts can be detected by treating the sample 
 of oxalate of potash with an excess of ammonia, and adding sulphide of 
 ammonium. 
 
 Manganate of Potash. 
 Manganate of potash is obtained by heating peroxide of manganese with 
 caustic potash, dissolving and crystallising; it occurs in crystals of a fine 
 green colour. The evaporation must be conducted in vacuo. The application 
 is limited to the restoration of indigo colours. 
 
 Permanganate of Potash. 
 
 Permanganate of potash, or chameleon salt, mineral chameleon, occurs in 
 red-purple crystals. It can be obtained by heating peroxide of manganese 
 with caustic potash, and treating the resulting mass with boiling water. 
 The salt can then be crystallised out by evaporation. It is a most powerful 
 oxidising agent, and has recently been applied to the bleaching of animal and 
 vegetable fibres. 
 
 Tartar. 
 
 The tartar of commerce is obtained from the only available source, from 
 wine tuns, where it is deposited as red tartar, cream of tartar, or bitartrate of 
 potash. Tartaric acid combines with potash to form two salts, the tartrate 
 and bitartrate of potash ; the former is very little known, but the bitartrate is 
 extensively employed under the name of argol, red tartar, or simply tartar. It is 
 employed in dyeing in its crude form, but for finer kinds of work it is necessary 
 that it should be twice re-crystallised. It is not readily soluble in water, 
 and at the usual temperature cannot be concentrated to a higher degree than 
 2° Tw. For cochineal-pink in calico-printing, and for mordanting woollen 
 goods, it is largely in demand, in the latter case being employed with alum and 
 salts of tin. Besides its application as an acid, tartaric acid possesses the 
 remarkable property of masking metals or preventing their precipitation under 
 the influence of potash ; thus potash will not throw down a precipitate from a 
 solution of sulphate of copper to which tartaric acid has been added. Many 
 substitutes have been suggested and sold for tartaric acid, but their success 
 has always been doubtful. The purity of tartaric acid or bitartrate of potash 
 can be determined by calcining a sample in a porcelain crucible. If the acid 
 is pure nothing but a black coke will remain, and this will disappear at a 
 higher temperature. The potash salt should leave either a white or grey 
 residue. An admixture of sulphates may be detected by means of chloride 
 of barium. Copper salts may be detected by ammonia, and salts of the 
 protoxide of iron may be deposited as sulphides by sulphide of ammonium 
 after the addition of ammonia. 
 
 Potash Water-Glass. 
 Potash water-glass, KO,Si0 2 , is made of 45 parts of pulverised quartz, 
 30 parts of potash, and 2 parts of wood charcoal strongly heated together. 
 Potash water-glass occurs in commerce in both fluid and solid form. Fluid 
 water-glass is a yellow, thick, fluid, which by exposure to the air suffers little 
 conversion. It colours litmus paper blue. As a fixing agent water-glass is 
 largely employed in printing. 
 
SODA SALTS. 
 
 "3 
 
 Chlorate of Potash. 
 Chlorate of potash, KO,C10 5 , is prepared by passing chlorine into a hot 
 concentrated potash lye, and is separated by cooling the fluid, in which it is 
 not very readily soluble. By heating chlorate of potash the oxygen is set 
 free, and chloride of potassium remains. In dyeing it is used as an ageing 
 material, especially in conjunction with steam, and in several methods to be 
 described in the course of the work. Its chief impurities are chloride of 
 potassium and nitrate of potash. 
 
 Hypochlorite of Potash. 
 
 Of this salt we shall speak more fully under the head of Chlorimetry. Its 
 
 formula is KO.CIO ; it is a yellow-tinted fluid with a peculiar odour. The 
 
 chief application is as a bleaching agent. It may be prepared by passing 
 
 chlorine into a dilute and cold solution of potash until the alkaline reaction 
 
 ceases. 
 
 SODA SALTS. 
 
 Carbonate of Soda. 
 
 Carbonate of soda, or, simply, soda, NaO,C0 2 , occurs in commerce as an 
 artificial product, and partly as the result of the calcination of plants. It is 
 also found native in the waters of certain lakes and in sea water. The plants 
 from which soda-ash is prepared grow, and in many instances are specially 
 cultivated, near the sea shore. The genera chiefly employed, in addition to 
 the species of Fuchs thrown up by the sea itself, are those known as Salsola, 
 A triplex, Salicornia, &c. The process of burning is of a most primitive kind, 
 and is conducted in pits dug in the sand of the sea shore. The heat of com- 
 bustion is generally very intense, and the ash appears as a hard, semi-fused 
 mass, termed in the trade crude soda or soda-ash, or sal-soda. The best variety, 
 termed Barilla soda, is that obtained from Alicante, Malaga, Carthagena, the 
 Canary Islands, and contains on an average 25 to 30 per cent of carbonate 
 of soda. The next place as regards value is held by Blanquettc soda imported 
 from Aigues-Mortes, while an inferior variety in common use is the Varec 
 soda, calcined on the coasts of Normandy and Brittany from the Funis 
 vesiculosus. 
 
 The artificial preparation of soda-ash may be considered as one of the 
 most perfect processes of manufacturing chemistry ; indeed, one might say the 
 most perfect and complete process that could be devised. The importance of 
 the invention of M. Leblanc is almost without parallel, especially when there 
 is added the improvement of the recovery of the sulphur from the soda-waste. 
 The process consists of four stages, all of which we shall, as briefly as possible, 
 describe under the following heads : — 
 
 r. Sulphate of soda is prepared from salt by treatment with sulphuric acid, 
 or by roasting common salt with a native metallic sulphuret, such as 
 iron pyrites. 
 
 2. The sulphate is converted into crude soda by roasting with a mixture 
 
 of chalk and small coal. 
 
 3. The crude soda is refined by lixiviation and evaporation. 
 
 4. The obtaining of sulphur from the soda-waste. 
 
 1. Sulphate of soda is generally obtained by treating common salt with 
 sulphuric acid, the hydrochloric acid gas being condensed in condensing- or 
 
ii4 DYEING AND CALICO PRINTING. 
 
 so-called coke-towers. These towers are stone built, the stone being of a 
 kind not acted upon by hydrochloric acid, cemented with coal-tar and fire-clay. 
 The dimensions of the towers vary between 36 and 42 feet for the height, and 
 4 to 5J feet internal width. A wall divides the tower nearly throughout its 
 length into two compartments, the dividing wall being carried to within a 
 short distance of the top of the building. The two compartments are filled 
 with pieces of coke resting on a perforated stone floor, and over the surface of 
 the coke, from the top of the tower, water is caused constantly to trickle. 
 The gas from the decomposed salt is conducted by stoneware tubes to these 
 towers, and is there condensed, so that only a fraction of a per cent escapes 
 into the chimney stalk, with which the second compartment of the coke- 
 tower is connected. 
 
 The furnace in which the salt is decomposed consists of two muffles. One 
 of the muffles is of fire-brick, and encloses a space of 30 feet in length by 
 9 feet in width, vaulted and so provided with flues that the flames may have 
 complete circulation. The other muffle is of cast-iron, the interior forming a 
 segment of a circle of g feet diameter, and 1 foot 9 inches in depth. A lid, also 
 of iron, is provided with two openings, one of which communicates with 
 the second muffle, while the other serves for the introduction of the salt. 
 Half a ton of common salt having been introduced into this muffle, sufficient 
 sulphuric acid (1-7 sp. gr.) is added to form a neutral sulphate. 95 parts of 
 acid of 17 sp. gr., or 104 parts of an acid at 1-62 sp. gr., are required to com- 
 pletely decompose 100 parts of salt. When the mixture of acid and salt is 
 dry it is raked over into the second muffle, kept at a bright red-heat to expel 
 the hydrochloric acid gas. Many large firms in this manner decompose 500 tons 
 of common salt per week. 
 
 2. The next part of the process consists in the conversion of the sulphate 
 into crude soda ; and this is effected by submitting a mixture of — 
 
 Sulphate 100 parts. 
 
 Chalk 100 „ 
 
 Slaked lime 50 „ 
 
 to fusion in a reverberatory furnace. Another mixture of — 
 
 Sulphate 100 parts. 
 
 Chalk go to 121 ,, 
 
 Small coal 40 to 75 ,, 
 
 is preferred in some works. The furnace employed is generally a balling 
 furnace, shown in Fig. 12. Mr. Wright has found that the loss of soda amounts 
 during this process to 20 per cent of the sodium contained in the sulphate, as 
 in the following proportions — 
 
 Undeconiposed sulphate 3*49 
 
 Insoluble sodium compounds 5*44 
 
 By volatilisation 1*14 
 
 In the waste 3'6i 
 
 During evaporation of the liquors . . . . 6-56 
 
 20'24 
 
 The composition of the crude or ball soda may be represented by the 
 following percentical analysis : — 
 
CARBONATE OF SODA. 
 
 "5 
 
 Carbonate of soda 45 
 
 Sulphuret of calcium 30 
 
 Caustic lime 10 
 
 Carbonate of lime 5 
 
 Foreign matter 10 
 
 3. The next stage is the refining of the crude soda by lixiviation and evapora- 
 tion. 100 parts of raw soda have been found to yield — 
 
 Soluble matter 45-0 parts. 
 
 Soda-waste 55-7 fl 
 
 1007 >> 
 We shall presently see how this waste is made a source of profit to the 
 
 manufacturer, but we must now continue to trace the course of the product in 
 
 which our reader is immediately interested. 
 
 The lixiviation can be effe&ed by simple filtration, the lumps of crude soda 
 
 being generally placed in tanks with perforated bottoms, but this method entails 
 
 Fig. 12. 
 
 great labour. The method of lixiviation invented by Mr. James Shanks, 
 of St. Helen's, is the most economical, as well as the most philosophical. 
 The apparatus is based upon the principle that a short column of a liquid of 
 superior density can be made to balance a higher column of a liquid of an 
 inferior density. A series of tanks are placed together, as shown in the wood- 
 cut, Fig. 13, each tank being about 7 feet 6 inches broad, by 6 feet in depth. 
 
 Fig. 13. 
 
 At the bottom of the tank is a perforated false sheet-iron bottom, A. From the 
 bottom of each tank to the top is carried a pipe, n, to which, at right angles, 
 is fitted a smaller pipe, b, communicating with the next tank. Water can be 
 supplied to each tank from the pipes, c ,• and by means of the taps, c, the lye 
 can be run off into a trough, d. In the first tank is placed crude soda that 
 
 1 2 
 

 
 116 DYEING AND CALICO PRINTING. 
 
 has been thrice lixiviated, and to it is added a very weak soda solution of such 
 a density that it will percolate into the second tank, where it passes over soda 
 that has been twice lixiviated. Percolating to the third tank, it meets with 
 soda having been lixiviated but once; and thence passes into the fourth 
 tank, where fresh soda has been placed. From the last tank it passes to a 
 reservoir. The first tank is now emptied of soda-waste, and charged with 
 fresh ball soda, and the operation reversed. By this method great waste of 
 labour is prevented, as the increasing gravity of the liquor causes it to do its 
 own work, while the high degree of concentration of the lye effects a con- 
 siderable saving in fuel during evaporation. 
 
 The composition of the crude lye may be represented by the following 
 analysis : — 
 
 Caustic soda 24*500 
 
 Carbonate of soda 71*250 
 
 Chloride of sodium 1850 
 
 Sulphate of soda o - io2 
 
 Hyposulphite of soda 0*369 
 
 Sulphuret of sodium 0*235 
 
 Cyanide of sodium 0*087 
 
 Argillaceous earthy matter . . .. 1*510 
 
 Silica 0*186 
 
 Iron traces 
 
 100*089 
 The lye may be at once evaporated to dryness to obtain a homogeneous pro- 
 duct containing all the above constituents ; or it may be evaporated to a 
 certain degree of concentration, the crystalline carbonate of soda being 
 separated on cooling by means of perforated ladles. The quality of the 
 commercial article is determined by the care with which the evaporation has 
 been conducted. There are several processes in vogue by which the evapora- 
 tion is well and quickly effected, but upon which it would be out of place to 
 enter here. Tissandier has shown the composition of refined soda to be for 
 five samples the following: — 
 
 1. 2. 3. 4. 5- 
 
 Moisture .. .. 2*22 311 1*15 i*oo 0*40 
 
 Insoluble matter . . 0*12 0*22 0*08 — 0*06 
 
 Chloride of sodium 12*48 6*41 3*28 211 0*99 
 
 Sulphate cf soda. . 8*51 3*25 2*15 1*50 0*35 
 
 Carbonate of soda 7667 87*01 92*34 95*39 98*20 
 
 IOO'OO 100*00 IOO'OO 100*00 100*00 
 While the composition of the soda containing caustic soda was, for four 
 
 analyses — 
 
 1. 2. 3. 4. 
 
 Moisture 2*10 1*50 2*48 1*38 
 
 Insoluble matter 0*12 o*n o*2i 0*09 
 
 Chloride of sodium .. .. 4*32 2*43 3*50 4*11 
 
 Sulphate of soda 8*8o 1*62 2*15 2*50 
 
 Carbonate of soda 82*47 88*09 84*54 81*67 
 
 Caustic soda 2*n 6*25 7*12 10*25 
 
 100*00 100*00 ioo*oo 100*00 
 
SODA SALTS. 
 
 117 
 
 So far we have dealt with Leblanc's process in its originality ; the plan of 
 M. Schaffner for regenerating the sulphur from the soda-waste we will touch 
 upon presently. Meanwhile it will be interesting and instructive to consider 
 the theory of the process as far as we have presented it to our reader. For 
 the elucidation of the theory we are indebted to the researches of Mr. Gossage 
 and M. Scheurer-Kestner. Chemists long held that the calcination of a 
 mixture of sulphate of soda, carbonate of lime, and carbon resulted in the 
 carbon yielding carbonic oxide, and converting the sulphate of soda into 
 sulphuret of sodium, this in turn becoming decomposed by the carbonate of 
 lime, yielding ultimately carbonate of soda, oxysulphuret of calcium, and 
 carbonic acid according to the following formulae : — 
 (1). Na 2 S0 4 + 4C = Na 2 S + 4CO. 
 (2). 2Na 2 S+3CaC0 3 = 2Na 2 C0 3 + CaO,2CaS + C0 2 . 
 
 But Unger has proved beyond doubt that only carbonic acid, and not the 
 lower oxide of carbon, is formed, the carbonic oxide resulting merely from 
 excess of carbon and its action upon the carbonate of lime. The reduction of 
 the carbonate of lime by the carbon is effected at a much higher temperature 
 than that at which the sulphate is reduced, so that carbonate of soda is formed 
 before carbonic oxide. Unger therefore distinguished three stages in the 
 process, viz. : — 
 
 1. During [the reduction of the sulphate, the evolution of carbonic acid, 
 according to the formula — 
 
 Na 2 S0 4 +2C = Na 2 S + 2C0 2 . 
 
 2. The sulphuret of sodium and carbonate of lime are decomposed — 
 
 Na 2 S + CaC0 3 = Na 2 C0 3 + CaS. 
 
 3. The excess of carbonate of lime is reduced by the carbon — 
 
 2CaC0 3 + 2C = 2CaO + 4CO. 
 
 Theory gives 100 parts of sulphate as requiring only 20 parts of carbon, but 
 in practice as much as 35 to 75 per cent of carbon is employed. 
 
 We now turn to the utilisation of the soda-waste by the process carried 
 out by M. Schaffner. Of the importance of the improvement upon Leblanc's 
 process, it may be stated that the accumulated waste from the alkali works at 
 Dieuze contains, according to M. Oppenheim, ,£150,000 worth of sulphur. 
 M. Schaffner's method includes three processes : — 
 
 1. The preparation of the waste liquor, or liquor containing the sulphur. 
 
 2. The decomposition of the sulphur. 
 
 3. The refining or preparing of the sulphur for the market. 
 
 1. The soda-waste is permitted to oxidise in heaps in the open air, the result 
 being the formation of oxysulphurets and polysulphurets, and subsequently 
 hyposulphites. The lumps of waste are then lixiviated, and a concentrated 
 liquor obtained, the waste being allowed to remain in the tanks, while heated 
 gases from a chimney are forced through perforations in the bottom of the 
 tanks ; after eight to ten hours the liquor is collected in a reservoir. 
 
 2. The lixiviation liquor is next decomposed by hydrochloric acid in closed 
 stone or iron vessels, sulphurous acid gas being evolved and sulphur precipitated. 
 
 CaS 2 3 + 2HCl = CaCl 2 + S0 2 +S + H 2 0. 
 
 3. The sulphur is very simply prepared, being mixed with water to a paste, 
 and subjected to the heat of steam at a pressure of if atmospheres. The 
 molten sulphur settling to the bottom of the vessel is run off into moulds, 
 
HH- 
 
 118 
 
 DYEING AND CALICO PRINTING. 
 
 There are many other methods of preparing soda from the sulphate, but we 
 must refer our readers to works on technology for the detail of the several 
 processes. 
 
 The value of a soda depends upon the quantity of anhydrous carbonate ot 
 soda it contains, ascertained by the following method of titration : — 
 
 ioo grains of soda are weighed out and dissolved in 500 grains of water in 
 a titration glass. Into another 500 grains of concentrated sulphuric acid 
 are introduced, and the acid is added to the alkali grain by grain until 
 it reads neutral to test-paper. The loss in weight is the loss of carbonic 
 acid, and as 4i'43 parts by weight of carbonic acid correspond to 100 parts 
 by weight of anhydrous carbonate it is easy to estimate the quantity of true 
 carbonate contained in a given sample. For example : Suppose the loss of 
 carbonic acid equals 38, then 
 
 41-43 : 100 = 38 : 917 per cent of anhydrous carbonate of soda. 
 
 If the soda should contain caustic soda, this must be converted into car- 
 bonate before titration by boiling for some time with carbonate of ammonia. 
 
 The soda should entirely dissolve ; but if a residue remain this must be 
 repeatedly lixiviated until the wash-water no longer causes turmeric paper to 
 become tinged. This wash-water should be added to the solution, and the 
 titration proceeded with as if the soda were entirely soluble. 
 
 When treating of alkalimetry we shall speak in more detail of the process 
 of estimating the value of alkalies. 
 
 Silicate of Soda. 
 
 Silicate of soda, or soda water-glass (NaO,Si0 2 ) may be prepared by fusing 
 together 45 parts of quartz sand, 23 parts of calcined soda, and 3 parts of 
 carbon ; or more simply by fusing 100 parts of pulverised quartz, and 60 parts 
 of calcined Glauber-salt with 15 to 20 parts of carbon, pulverising the fused 
 mass, and treating it with boiling water. 
 
 In a fluid condition water-glass may be diredtly prepared by heating finely 
 pulverised quartz with a strong solution of caustic soda in an iron vessel under 
 a pressure of 8 atmospheres. 
 
 In a dry condition soda water-glass can be prepared by fusing together the 
 ingredients in the foregoing proportions. Water-glass in a pure state and 
 free from sulphur may be prepared by fusing, for twelve hours, 120 parts by 
 weight of finely pulverised quartz with 100 parts of best calcined soda and a 
 quantity of carbon (coal). By this method a water-glass can be obtained as 
 clear, hard, and colourless as the best window glass. From this product fluid 
 water-glass may be prepared by boiling with copper scales for ten hours until 
 the liquid acquires a density of 34 B. Water-glass thus obtained is especially 
 suited to the printer. It is employed as a substitute for dung, but principally 
 for fixing ultramarine-blue and pigment colours. The colour is well triturated 
 with a solution of silicate at 90° Tw. ; then printed on without thickening, dried 
 in a cool place ; the colour being fixed by passing the fabric through a solution 
 of chloride of ammonium or of common salt. But an unsatisfactory harshness 
 is imparted to the cloth, and the colour is apt to come away in the fixing bath. 
 It serves also in place of borax in the bath for dyeing Nicholson and Guernsey 
 blues and Pomona greens. 
 
SODA SALTS. 
 
 ng 
 
 Chloride of Sodium. 
 Common salt, or chloride of sodium (NaCl), finds but few direcT; appli- 
 cations in the branch of industry under consideration. 
 
 Hypochlorite of Soda. 
 
 Hypochlorite of soda, NaO.CIO, also known as chloride of soda, serves as 
 a bleaching agent and in the preparation of several colours. It is prepared 
 by the decomposition of chloride of lime with carbonate or with sulphate of 
 soda, or by passing chlorine into a solution of carbonate of soda. 
 
 The bleach liquor is of a yellow colour, with a strong odour of hypochlorous 
 acid. 
 
 Hypochlorite of soda can be subjected to the same tests as to strength aa 
 hypochlorite of lime, and we shall revert to the subject when treating of 
 Chlorimetry. A hypochlorite of soda bath at g° B. is obtained when 6J lbs. of 
 hypochlorite of lime at 8° B. are added to i£ lbs. crystallised soda. It can 
 be employed in the bleaching of white grounds upon brilliantly coloured cotton 
 fabrics. 
 
 Phosphate of Soda. 
 Phosphate of soda, Na03P0 5> is but seldom used in calico-printing. It 
 partakes of the character of a weak alkali, and is used as a solvent for ladtarine. 
 As an alkaline salt it causes the precipitation of a greater quantity of iron 
 from citrate or sulphate solutions of iron mordant, and hence gives rise to a 
 depth of colour known as a double shade. 
 
 Permanganate of Soda. 
 Permanganate of soda, NaO,Mn 2 7 , which is employed as often as per- 
 manganate of potash for technical purposes, is of high value as an oxidising 
 agent for bleaching or for disinfecting. It may be obtained by fusing in an 
 iron vessel 10 parts of caustic soda with i part of nitrate of potash, to which 
 is added in small portions on an iron spatula 6 parts of peroxide of 
 manganese. The fused mass is lixiviated with boiling water, and the salt 
 crystallised out by evaporation. A crude permanganate may be obtained by 
 heating to redness with access of air a mixture of 2 parts of nitrate of soda 
 with i part of peroxide of manganese. 
 
 Tungstate of Soda. 
 
 Tungstate of soda is employed in the fixation of logwood pigments. 
 In colouring sheep's wool it is substituted for tin salts. 
 
 Tungstate of soda may be prepared by heating 5 parts of tungstic acid 
 with 5 parts of calcined soda in an iron capsule; the tungstate is obtained by 
 dissolving the fused mass in water, and then concentrating the solution by 
 evaporation. 
 
 Hyposulphite of Soda. 
 This salt is used in fixing aniline greens upon the fibre, and is hence known 
 in the trade as " green mordant." In conjunction with salts of copper it has 
 been employed in the produ&ion of so-called " argentine " effects, a thin film 
 of sulphide of copper being deposited on the fibre. 
 
DYEING AND CALICO PRINTING. 
 
 LIME SALTS. 
 Hypochlorite of Lime. 
 
 Hypochlorite of lime, CaO,C10, generally known as chloride of lime, occurs 
 in commerce chiefly in the solid state. Fluid chloride of lime is simply a 
 milk of lime saturated with chlorine, and appears as a yellow fluid possessing 
 a peculiar odour. As access of air causes decomposition of the fluid chloride, 
 it must be kept in closed vessels. In the solid state chloride of lime is a 
 white mass, very hygroscopic, and easily decomposed by the action of the 
 carbonic acid of the atmosphere. Hypochlorite of lime is most extensively 
 employed as a bleaching agent, in very dilute solutions for the scouring of 
 woven fabrics, in fixing and shading colours, and in printing to remove colours 
 in order to show a white ground. Of the methods of preparing and estimating 
 chloride of lime we shall speak more fully under the head of Chlorimetry. 
 
 A solution of hypochlorite of lime has but little effecT: upon colouring- 
 matters. This influence is increased by the addition of such acids or salts as 
 cause the decomposition of the hypochlorite and the formation of free chlorine 
 or hydrochloric acid. The powerful affinity of chlorine for hydrogen is in 
 most cases the cause of the bleaching power of the hypochlorite of lime, and 
 this affinity may produce its effect in two ways : — 
 
 1. By the direct removal of the hydrogen from the organic matter. 
 
 2. By decomposing the water in which the hydrogen and chlorine are 
 in combination, and setting free the oxygen to act upon the carbon of the 
 colouring-matter, oxidising it to carbonic acid, and to again combine with 
 the hydrogen to form water. 
 
 We know, however, but little of the true adtion of chloride of lime. 
 
 AMMONIACAL SALTS. 
 Ammonia. 
 Ammonia is not largely employed in dyeing and printing. It is used in 
 scouring, to fix metallic mordants, to produce with cochineal a crimson colour, 
 to fix murexide, to modify the shades produced by a variety of colouring- 
 matters, but chiefly, as is the case with its salts, for ageing purposes, 
 especially with heavy mordants. When pure it does not leave any residue 
 upon evaporation, and should yield no precipitate with sulphuretted hydrogen. 
 The following tahle shows the percentage of ammonia according to the 
 density at 62 F. 
 
 Sp. gr. of the 
 Liquid Ammonia. 
 
 Per cent of Ammonia 
 by Weight. 
 
 Sp 
 Liqui 
 
 gr. of the 
 d Ammonia. 
 
 Per cent of Ammonia 
 by Weight. 
 
 0-875 
 
 34 - 694 
 
 
 0-930 
 
 18-280 
 
 o-88o 
 
 33""7 
 
 
 0-935 
 
 16883 
 
 0-885 
 
 3I-558 
 
 
 0-940 
 
 15-502 
 
 0-900 
 
 26-984 
 
 
 o-945 
 
 I4-I35 
 
 0-905 
 
 25-493 
 
 
 0-950 
 
 12-782 
 
 0-910 
 
 24-019 
 
 
 0-955 
 
 1 1 -444 
 
 0-915 
 
 22-561 
 
 
 0-960 
 
 10-119 
 
 0-920 
 
 21-118 
 
 
 0965 
 
 8-808 
 
 0-925 
 
 19-961 
 
 
 0-970 
 
 7'5 X 1 
 
AMM0N1ACAL SALTS. 
 
 Carbonate of Ammonia. 
 Carbonate of ammonia (NH 4 0,C0 2 ), occurs in commerce as a white crys- 
 talline mass smelling strongly of ammonia and soluble in water. It has but 
 a small number of applications in dyeing, being chiefly employed to brighten 
 colours, especially magenta, to form a soap with the grease of certain fibres, &c. 
 
 Sal-Ammoniac. 
 Sal-ammoniac, or chloride of ammonium, NH 4 C1, forms a colourless 
 crystalline mass, the whole of which, when pure, is volatile by heat. The 
 crystals not unfrequently contain salts of iron, contracted from the vessels 
 in which the sal-ammoniac has been prepared. An aqueous solution of sal- 
 ammoniac, in which nitrate of potash has been boiled, should not, after 
 cooling, exhibit a red colouration on the addition of sulphocyanide of 
 potassium. Sal-ammoniac is employed in the preparation of certain baths, 
 as well as in the precipitation of alumina from aluminate of soda. It modifies 
 the action of metallic salts upon organic colours, and is extensively used along 
 with compounds of copper. It serves in the preparation of pink-salt. 
 
 Nitrate of Ammonia. 
 Nitrate of ammonia possesses the property, by means of the ammonia it 
 contains, of depositing from the acetate of alumina baths the mordant in a 
 basic condition, and by the nitric acid it contains to oxidise the protoxide of 
 iron of the iron-bath to a higher oxide. Better results can be obtained in 
 printing catechu shades and garancine colours, with a bath of nitrate of 
 ammonia (i° to 3 B.) than with chlorate of potash. 
 
(122) 
 
 CHAPTER XV. 
 
 ALKALIMETRY. 
 
 / T <l HE chemical principles employed in the processes of alkalimetry, based 
 upon the law of chemical combination, are to be found described in any 
 elementary work upon the science of chemistry ; we shall here detail the 
 technical processes of determining the value of alkalies. 
 
 The Test Solutions. 
 Having decided upon the form of alkalimeter or burette to be employed, it 
 is necessary to prepare the test solutions, or solutions containing a known 
 proportion of the reagent to be employed. The test solutions used in 
 alkalimetry are an acid of known density and a solution of litmus ; the latter 
 being coloured blue by alkalies and red by acids serves to indicate that 
 neutral point at which no free acid exists. 
 
 The Litmus Solution. 
 The litmus solution is prepared by pulverising i part of commercial 
 litmus, and digesting it with 8 parts of cold water for twelve hours. The 
 solution should be filtered off, and divided into two portions, to one of which 
 sulphuric acid is added drop by drop until the litmus shows a red tinge. This 
 solution should then be poured into the other. The litmus solution thus pre- 
 pared is neutral and very sensitive. 
 
 Normal Sulphuric Acid Solution. 
 
 One volume of ordinary strong sulphuric acid is diluted with 30 volumes 
 of water, and allowed to cool. 10 c.c. of the normal soda solution, to be 
 presently described, to which some litmus solution has been added, are then 
 employed to calibrate the sulphuric acid, water being added to the latter until 
 1 volume of the acid is exactly equivalent to 1 volume of the alkaline 
 solution. Or very excellent results may be obtained by mixing 40 grms. of 
 chemically pure sulphuric acid with 1000 c.c. of water. 1 c.c. of the normal 
 acid solution then corresponds to 0*04 grm. of sulphuric acid, from which the 
 strength of a solution of soda may be calculated. 
 
 Another method of preparing an acid solution of known strength is as 
 follows: — 11276 grs. of pure neutral and anhydrous carbonate of soda are 
 dissolved in 5 fluid ozs. of hot water ; the anhydrous soda being obtained by 
 maintaining pure bicarbonate of soda for some hours at a dull red heat in a 
 platinum crucible. This quantity of neutral carbonate of soda corresponds 
 to 100 grs. of pure potash, that is, 100 grs. of potash and ii2 - 76grs. of neutral 
 carbonate of soda saturate exactly the same quantity of sulphuric acid. This 
 
ALKALIMETRY. 
 
 123 
 
 Fig. 14. 
 
 aqueous solution of carbonate of soda should exactly saturate the contents of 
 an alkalimeter, divided into 100 parts, filled with 1000 water-grains' weight of a 
 solution of 1 part of concentrated sulphuric acid in 10 parts, by measure or 
 volume, of water, so that the litmus solution becomes coloured very slightly 
 red. But should only 90 volumes of the acid be required to saturate the soda 
 solution, it is evident that to render the acid solution of the required strength, 
 there must be added to every 90 volumes of it 10 volumes of water. 
 
 The acid solution adjusted for the assay of soda should be of such a 
 strength that 100 divisions of an alkalimeter capable of containing 1000 grs. 
 of water will exactly neutralise 170-98 (in practice 171) grs. of pure anhydrous 
 carbonate of soda, or 100 grs. of pure soda. 
 
 The alkalimeter described by Faraday is suited to the estimation of potash 
 
 r soda, or of either or both of their carbonates. He says, " Let the tube 
 represented in the margin, Fig. 14, have 100 grs. of water weighed into it ; 
 then let the space it occupies be graduated into 100 equal parts, and every 
 ten divisions numbered from above downwards. At 22' 1 parts, or 
 77-99 parts from the bottom, make an extra line a little on one 
 side, or even on the opposite side of the graduation, and write 
 at it with a scratching diamond soda; lower down, at 48-62 
 parts, make another line, and write potash ; still lower, at 
 54-43 parts, a third line carb. soda ; and at 65 parts a fourth, 
 marked carb. potash. It will be observed that portions are 
 measured off beneath these marks in the inverse order of the 
 equivalent number of these substances, and consequently 
 directly proportionate to the quantities of any particular acid 
 which will neutralise equal weights of the alkalies and their 
 carbonates. As these points are of great importance, it will be 
 proper to verify them by weighing into the tubes first 350, then 
 513-8, and lastly 779-9 grs. of water, which will correspond 
 with the marks if they are correct, or the graduation may be 
 laid down from the surface of the four portions of fluid when 
 weighed in, without reference to where they fall upon the general 
 scale. The tube is now completed, except that it should be 
 observed whether the aperture can be perfectly and securely 
 :overed by the thumb of the left hand, and if not, or if there 
 be reason to think it not ultimately secure, then it should be 
 heated and contracted until sufficiently small." The acid for 
 use with this alkalimeter should have a sp. gr. of i'i268 ; it may 
 be prepared by mixing 1 part by weight of sulphuric acid of 1-82 sp. gr. with 
 4 parts of water. This acid having been poured into the alkalimeter to 
 the point marked carbonate of soda should neutralise exactly 100 grs. of 
 pure anhydrous carbonate of soda dissolved in water. 
 
 The most perfect method, however, results from the preparation of a normal 
 acid, so adjusted that 100 alkalimetrical divisions will exactly neutralise 
 1 equivalent of every base. This acid should have a sp. gr. of 1-032, and may 
 be prepared in the manner described by Dr. Ure as follows : — 
 
 "Take 53 grs. (1 equivalent) of pure anhydrous neutral carbonate of soda, 
 and dissolve them in about 1 fluid ounce of water. Prepare, in the meantime, 
 the test sulphuric acid by mixing 1 part by measure of concentrated 
 
 CARB.S0OA- S. g b 
 ^ — 60 
 §-65 
 L_70 
 I 76 
 4.81! 
 
 c-85 
 
 =. 95 
 

 124 
 
 DYEING AND CALICO PRINTING. 
 
 sulphuric acid with about n or 12 parts of water, and stir the whole well. The 
 mixture having become quite cold, fill the alkalimeter with the cold diluted 
 acid up to the point marked o°, taking the under line of the liquid as the true 
 level, and, whilst stirring briskly the aqueous solution of the 53 grs. of car- 
 bonate of soda, pour the acid carefully from the alkalimeter into the vortex 
 produced by stirring, until, by testing the liquor alternately with reddened 
 and with blue litmus paper, or, more conveniently still, with grey litmus paper, 
 the neutralising point is exactly hit." This acid may be termed simply 
 normal sulphuric acid, and every 100 alkalimetrical degrees, or 1000 water- 
 grains' measure of it, contain 1 equivalent or 40 grs. of anhydrous sulphuric 
 acid, capable of saturating or neutralising 1 equivalent or 47 grs. of potash, 
 31 of soda, 28 of lime, 17 of ammonia, and indeed an equivalent of any other 
 alkaline base. 
 
 For further detail as to the preparation of reagents in a state of chemical 
 purity for more delicate estimations than are required in commercial 
 laboratories, the reader should refer to works of scientific research. 
 
 Normal Oxalic Acid Solution. 
 Mohr was the first to substitute oxalic acid for sulphuric acid in the de- 
 termination of the value of carbonated and caustic alkalies. It is similar in 
 its action upon litmus ; and it can be readily and accurately weighed in a dry 
 state. Mohr recommends that the solution be prepared by dissolving 63 grms. 
 of oxalic acid perfectly dry but not effloresced in a litre of water, while a 
 solution of caustic potash is so adjusted that, bulk for bulk, it neutralises 
 the acid, 6 - gn grms. of potash or 5-32 grms. of soda should be weighed out, 
 these quantities corresponding to 0-05 of a molecule ; so that as 1000 c.c. of 
 the test acid contain a half molecule of oxalic acid, 100 c.c. will exactly 
 neutralise the quantity of alkali. The oxalic acid solution is added to the 
 alkaline solution to be tested with an excess of 5 to 6 c.c. ; by this excess 
 the litmus is turned a wine-red. By means of a pipette divided into tenths 
 of a cubic centimetre the alkaline solution is added until the litmus is again 
 coloured blue. The number of c.c. of test acid employed, minus the number 
 of c.c. of alkali employed, gives the percentage of pure carbonate of potash. 
 Thus, if the sample weighed out were 6*90 grms. of the potash, and 
 72 c.c. of the acid and 6 c.c. of the alkaline liquor were employed, 
 72 — 6 = 66 per cent of carbonate of potash. 
 
 Normal Hydrochloric Acid Solution. 
 A normal solution of hydrochloric acid contains 36-5 grms. of chemically 
 pure hydrochloric acid in 1000 c.c. of distilled water. 1 c.c. of the normal 
 acid then contains 0*036 grm. of hydrochloric acid. 
 
 Normal Nitric Acid Solution. 
 A normal solution of nitric acid contains 54 grms. of chemically pure nitric 
 acid in 1000 c.c. of distilled water. 1 c.c. of the normal acid, then, contains 
 0*054 grm. of nitric acid. 
 
CARBONATED ALKALIES. 
 
 125 
 
 The Estimation of Carbonated Alkalies. 
 It is evident from the consideration of the constitution of the carbonated 
 alkalies that the quantitative determination may be effected with sufficient 
 accuracy for commercial purposes in two ways : — 
 
 1. By estimating the percentage of alkali from the quantity of acid required 
 
 for neutralisation. 
 
 2. By determining the quantity of carbonic acid evolved by the addition of 
 
 an acid. 
 
 Besides the methods already detailed in several processes throughout the 
 work, we shall here present to the reader some further modes of estimating 
 the value of a sample of potash or soda-ash. 
 
 The operator should commence by taking the alkalimeter in the left hand, 
 filled with the test acid he wishes to employ; the beaker containing the acid 
 solution should be placed upon a sheet of white paper, and a stirring rod pro- 
 vided, with which the solution may be quickly stirred. 
 
 If the sample to be tested consists of carbonate of potash the first addition of 
 the acid produces no effervescence, because the carbonic acid expelled instead 
 of being set free from the solution combines with the carbonate of potash 
 remaining undecomposed to form bicarbonate of potash. Care must be taken 
 to drive off the liberated carbonic acid by heat, because the carbonic acid 
 set free exerts an influence in colouring the litmus red, and the acid should be 
 added until the solution assumes a distinctly pink colour. As long as any of 
 the bicarbonate remains undecomposed a vinous colour obtains, and the 
 addition of the acid should be continued until this disappears. The number 
 of divisions of the acid contained in the alkalimeter gives the percentage of 
 real potash. Thus, if 48 divisions have been used, the sample contains 
 48 per cent of pure potash. 
 
 Should Dr. Ure's alkalimetrical method of employing the acid of such a 
 density that 100 divisions correspond to 1 equivalent of base, that is to 47 of 
 potash, a simple proportion sum will give the percentage of potash. Thus, if 
 105 divisions have been used (that is, the alkalimeter has been re-filled, and 
 5 divisions of the second charge used), the proportion will be stated as — 
 
 — ~ = 49'35 P er cent of pure potash. 
 
 100 
 
 Some guide will be given to the operator by the following percentical 
 
 analyses of potash by M. Pesier: — 
 
 Sulphate of potash . . 
 Chloride of potassium 
 Carbonate of potash 
 Carbonate of soda . . 
 Insoluble residue 
 
 Moisture 7-28 
 
 Phosphoric acid, lime, 
 
 silica, &c 
 
 Alkalimetrical degree 
 
 Tuscan 
 Potash. 
 
 Russian 
 Potash. 
 
 American 
 
 Potash. 
 
 Pearlash. 
 
 Potash 
 from the 
 Vosges. 
 
 Valen- 
 ciennes 
 Potash 
 Purified. 
 
 I3H7 
 
 14*11 
 
 i5"32 
 
 I4-38 
 
 38-84 
 
 I- 5 
 
 0-95 
 
 2 •09 
 
 8-15 
 
 3'64 
 
 9'l6 
 
 i-6o 
 
 74-10 
 
 69-61 
 
 68-07 
 
 7I-38 
 
 38-63 
 
 89-95 
 
 3-01 
 
 309 
 
 5-85 
 
 2-31 
 
 4-17 
 
 5-12 
 
 0-65 
 
 1*21 
 
 3"35 
 
 0*44 
 
 266 
 
 — 
 
 7-28 
 
 8-82 
 
 — 
 
 4-56 
 
 5-34 
 
 0-50 
 
 0'54 
 
 1*07 
 
 — 
 
 3-29 
 
 1-20 
 
 i-33 
 
 56 
 
 53'i 
 
 55 
 
 54*4 
 
 31-6 
 
 68-5 
 
I 
 
 I2 6 DYEING AND CALICO PRINTING. 
 
 The amount of potash yielded by the ash of different plants Dr. Bottger 
 found to be as follows for iooo parts : — 
 
 Per Mille. 
 
 Pine °"45 
 
 Poplar o'75 
 
 Beech i - 45 
 
 Oak i-53 
 
 Boxwood 2-26 
 
 Willow 2-85 
 
 Elm 3-90 
 
 Wheat-straw 3'9° 
 
 Rushes 5'° 8 
 
 Vine-wood 5'5° 
 
 Barley-straw 5'&° 
 
 Bean-straw 2000 
 
 Vetch-straw 27-50 
 
 Wormwood 73'°° 
 
 Fumitory 79*00 
 
 The ash of the beech contained of — 
 
 Per cent. 
 
 Soluble salts 21-27 
 
 Insoluble salts 7873 
 
 The percentage of soluble salts consisted of — 
 
 Per cent. 
 
 Carbonate of potash I5'4° 
 
 Sulphate of potash 2-27 
 
 Carbonate of soda 3-40 
 
 Chloride of sodium 0-20 
 
 21-27 
 
 According to Dr. Hoss, 100 parts of the following woods give — 
 
 Ash. Potash. 
 
 Pine 0-34 0-045 
 
 Beech 0-58 0*127 
 
 Ash 1-22 0-074 
 
 Oak 135 0-150 
 
 Flm , 2-55 0-390 
 
 Willow 2-80 0-285 
 
 Vine 340 0-550 
 
 Wormwood 9-74 7-300 
 
 Fumitory 21-90 7'990 
 
 Calculated from analyses per mille. 
 
 Of the method of preparing the potash we need not here speak, except to 
 say that the ash is first lixiviated, the liquor boiled down to obtain the crude 
 potash by evaporation ; the crude potash is then calcined. After calcination 
 it is ready for the market, and is of various shades of colour, being either 
 white, pearl-grey, or tinged with yellow, red, or blue. The blue colour is due 
 to the manganates of potash; the red to oxide of iron. 
 
CARBONATED ALKALIES. tvf 
 
 The average composition of the refined potash obtained from the ash of 
 molasses is as follows : — 
 
 Carbonate of potash 94'39 8873 
 
 Carbonate of soda traces 6-44 
 
 Sulphate of potash 0-28 2*27 
 
 Chloride of potassium 2*40 i-oo 
 
 Iodide of potassium en 0*02 
 
 Water 176 1-39 
 
 Insoluble substances — 0*12 
 
 The crude potash from beet-root sugar works gives on analysis results 
 within the following limits : — 
 
 Carbonate of potash 32*9 to 79-0 
 
 Carbonate of soda 14*3 ,, 23*1 
 
 Sulphate of potash 1*19 ,, 14-0 
 
 Chloride of potassium 2-8 ,, ig'6 
 
 The percentage of carbonate of potash contained in a solution may, 
 according to Dr. Gerlach, be roughly estimated from the sp. gr. At 15 C. the 
 densities and percentages are : — 
 
 Specific Gravity. Percentage. Specific Gravity. Percentage. 
 
 1*009 1 I'30I 30 
 
 1*018 2 1-358 35 
 
 1-036 4 1-418 40 
 
 1-045 5 1*480 45 
 
 1-092 10 I *544 50 
 
 1-141 15 1-557 5i 
 
 1-192 20 I *570 52 
 
 1*245 2 5 
 
 The alkalimetrical estimation of soda-ash is proceeded with in the same 
 manner as that of potash, the test acid being adjusted so as to saturate an 
 equivalent of soda. 10 grms. of the soda-ash are to be dissolved in water, and 
 the solution diluted to 250 c.c. The solution, if not clear, should be filtered. 
 The water itself must be freed from carbonic acid by boiling, or distilled 
 water should be employed. From the filtrate 50 c.c are to be measured out, 
 containing, as 10 grms. were taken, 2 grms. of soda. These 50 c.c. are to 
 be coloured blue with the litmus solution, then titrated with the normal acid 
 solution, of which an excess may be employed, the solution being titrated 
 back with the normal soda solution. Suppose 30 c.c. of normal acid to have 
 been employed together with 4 c.c. of normal soda solution, then as 4 c.c. 
 of acid had been added in excess, the difference shows 26 c.c. to have been 
 necessary for the neutralisation of the alkaline carbonate. As 0-053 grm. of 
 carbonate of soda corresponds to 1 c.c. of the normal acid solution, we have 
 0-053 x 26= 1-378 grm. of carbonate of soda in 2 grms. soda-ash. The per- 
 centage can then, of course, be obtained by the following equation : — 
 
 2 : 1378 = 100 : x, 
 or x — 68-9 per cent of carbonate of soda. That is, 100 lbs. of soda-ash 
 contain 68-9 lbs. of pure carbonate of soda and 31-1 lbs. of impurities. 
 
Haw— ntamt 
 
 IBM 
 
 128 
 
 DYEING AND CALICO PRINTING. 
 
 These impurities generally consist of sulphide of sodium, hyposulphite and 
 sulphite of soda. They can be detected by the addition of ammonia and 
 nitrate of silver, by which a black precipitate is thrown down. If, after 
 heating the solution and adding more ammonia there still remains a black 
 precipitate, the solution contains hydrosulphuric acid and sulphite of soda. 
 
 If there be sulphide of sodium present, it will be recognised upon the addition 
 of the normal sulphuric acid by the formation of sulphate of soda and sul- 
 phuretted hydrogen, according to the following equation: — 
 NaS + HO,S0 3 = NaO,S0 3 + HS. 
 
 If sulphite of soda be present, it will be detected by the peculiar odour of the 
 sulphurous acid formed on the addition of the normal test acid, according to 
 the equation — 
 
 NaO,S0 2 + HO,S0 3 = NaO,S0 3 + HO + S02. 
 
 In the case of hyposulphite of soda the addition of the normal acid causes 
 decomposition into sulphate of soda, water, sulphurous acid, and sulphur. 
 NaO,S a 2 + HO,S0 3 = NaO,S0 3 + HO + S0 2 + S. 
 
 These impurities must be removed before an accurate test can be made, 
 because their action upon the litmus solution would lead to error in the esti- 
 mation of the amount of acid employed, and consequently the amount of pure 
 carbonate contained in the sample of soda-ash. MM. Fordos and Gelis 
 recommend the changing of the sulphurets, sulphites, and hyposulphites by 
 adding a little neutral chromate of potash to the alkaline solution, to obtain 
 sulphate of chromium, water, and a separation of sulphur. These reactions 
 do not affect the accuracy of the alkalimetrical process. 
 
 Estimation of Caustic Alkalies. 
 Caustic potash, KO,HO, is composed in 100 parts of 83*97 °f P ur e potash, 
 or anhydrous oxide of potassium, and 16-03 0I " water. It is prepared from a 
 crude carbonate of potash obtained from chloride of potassium, carnallite, 
 vinasse, or other sources, by lixiviating the crude carbonate, and rendering the 
 liquid caustic with quick-lime ; or by igniting a mixture of sulphate of potash, 
 limestone, and small coal, and lixiviating with water at 50° to yield at once 
 a solution of caustic potash. It may also be obtained by decomposing sulphate 
 of potash with caustic baryta ; by converting chloride of potassium into 
 silico-fluoride of potassium, and decomposing this salt with caustic lime ; or 
 by igniting nitrate of potash with copper-scale. The following table shows 
 the relation of sp. gr. to strength in caustic potash solutions : — 
 
 Percentage of Potash. Degrees Beaume. Specific Gravity. 
 47 9 ro6 
 
 95 15 I'" 
 
 130 19 1-15 
 
 162 24 rig 
 
 19-5 28 1-23 
 
 23-4 32 1-28 
 
 32-4 4i i"39 
 
 42-9 50 r 5 2 
 
 467 53 r6o 
 
 51-2 57 r6o 
 
CAUSTIC ALKALIES. 
 
 129 
 
 Percentage Potash. 
 
 Degrees Twaddle 
 
 5-0 
 
 10 
 
 7-0 
 
 14 
 
 IO'O 
 
 19 
 
 12*0 
 
 24 
 
 14*0 
 
 29 
 
 16-5 
 
 34 
 
 19*0 
 
 40 
 
 21'0 
 
 45 
 
 22-5 
 
 50 
 
 24 # o 
 
 53 
 
 25-0 
 
 55 
 
 26 
 
 60 
 
 270 
 
 63 
 
 28-0 
 
 66 
 
 1 c.c. of normal oxalic acid will neutralise 0^047 grm. of caustic potash. 
 
 Caustic soda, or hydroxide of sodium, NaHO, occurs in commerce in the 
 mass or in concentrated solutions. Fused hydrate of soda is composed in 
 100 parts of 77'5 parts of anhydrous soda and 22^5 parts of water. It may 
 be prepared from carbonate solutions by means of caustic lime, or by the 
 ignition of a mixture of sulphate of soda, chalk, and small coal, and lixiviating 
 the crude soda with water at 50 . The lixivium is concentrated to 1*5 sp. gr. 
 to deposit carbonate, sulphate of soda, and sulphide of sodium. The 
 liquor is kept boiling in iron cauldrons, and Chili saltpetre is then added, in 
 the proportion of 3 or 4 kilos, of the nitrate to every 100 kilos, of caustic 
 soda the solution is likely to yield. During the boiling the nitrate of soda 
 causes the evolution of ammonia and nitrogen by acting upon the sulphuret 
 and cyanide of sodium present in the solution. Pauli illustrates the reaction 
 by the following formulae : — 
 
 2NaS + 2NaN0 3 4-4H 2 = 2Na 2 S0 4 +2NaHO + 2HN 3 . 
 
 5Na 2 S+8NaN03+4H 2 = 5Na 2 S0 4 +8NaHO + 8N. 
 Dalton gives the following table of percentages of caustic soda contained 
 in solutions of the corresponding density: — 
 
 Specific Gravity. 
 
 Percentage 
 NaHO. 
 
 47 
 g-O 
 13-0 
 i6 - o 
 19*0 
 23-0 
 26*0 
 29-0 
 31*0 
 34*o 
 36-8 
 41-2 
 46-6 
 
 53*8 
 63-6 
 
 77-8 
 
 1 06 
 
 I-I2 
 
 1-18 
 123 
 1*29 
 1-32 
 1-36 
 1*40 
 1-44 
 1-47 
 1-50 
 
 156 
 1-63 
 172 
 1-85 
 2 -co 
 

 130 
 
 DYEING AND CALICO PRINTING. 
 
 ercentage 
 NaHO. 
 
 Degrees Twaddle. 
 
 3 '5 
 
 IO 
 
 5*0 
 
 14 
 
 6-5 
 
 *9 
 
 8-o 
 
 24 
 
 IO'O 
 
 29 
 
 "•5 
 
 34 
 
 13-0 
 
 40 
 
 M'5 
 
 45 
 
 16*0 
 
 50 
 
 I7'5 
 
 53 
 
 ig-o 
 
 56 
 
 20-5 
 
 60 
 
 22*0 
 
 &3 
 
 23-0 
 
 66 
 
 I c.c. of normal oxalic acid corresponds to 0*031 grm. of caustic soda. 
 
 Ammonia, NH 3 , is very variously prepared, and a description of the 
 principal processes would be necessarily too long for these pages. The 
 following table shows the percentage of ammonia contained in a solution of 
 the corresponding specific gravity : — 
 
 CTcentage 
 NH 8 . 
 
 Specific Gravity. 
 
 5 - 50 
 
 0-978 
 
 600 
 
 0-976 
 
 6-50 
 
 0-974 
 
 700 
 
 0-972 
 
 7 - 5° 
 
 0-970 
 
 8-oo 
 
 0-968 
 
 8-50 
 
 0-965 
 
 9/00 
 
 0-963 
 
 Q^o 
 
 0961 
 
 I0"00 
 
 o-959 
 
 10*50 
 
 ° - 957 
 
 II"00 
 
 o-955 
 
 11-50 
 
 o-953 
 
 1200 
 
 0-951 
 
 i3'46 
 
 0-947 
 
 I7'52 
 
 0932 
 
 19*54 
 
 0-925 
 
 25 "39 
 
 0-905 
 
 2600 
 
 0-900 
 
 3 X '30 
 
 0-824 
 
 3250 
 
 0-875 
 
 1 c.c. of normal oxalic acid neutralises exactly 0-017 grm. of caustic ammonia. 
 5 c.c. of the liquid ammonia to be tested should be taken in a pipette and 
 coloured blue with litmus solution. The normal oxalic acid solution is added 
 from the burette. Suppose 41 c.c. of the normal acid solution to have been 
 required to neutralise the ammonia, the 5 c.c. of liquid ammonia will have 
 contained 0-017x41=0-697 grm. of caustic ammonia. Suppose the liquid 
 
ACIDIMETRY. 131 
 
 ammonia marks upon the metrical hydrometer the degree C94, that is, 1 c.c. 
 weighs o - 94 grm., the 5 c.c. will weigh 0*94 x 5 = 4'7 grms. And as the 4^7 grms. 
 contain o'6g7 grm. of caustic ammonia, the equation 4*7 : 0^697= 100 : x 
 gives *=I4"8 percent of caustic ammonia. That is, that 100 lbs. of the liquid 
 ammonia contains i4 - 8 lbs. of caustic ammonia and 85'2 lbs. of water and 
 impurities. 
 
 Acidimetry. 
 Alkalimetry and acidimetry are characterised by precisely the same methods ; 
 a normal acid being used to estimate in the one case the percentage of 
 alkali, and a normal alkali in the other to estimate the percentage of pure acid 
 contained in an acid solution. 
 
 The litmus solution is, in the same manner as in alkalimetry, employed as 
 an indicator. 1 c.c. of normal soda solution contains 0*03 1 of caustic soda, 
 and will neutralise of — 
 
 Sulphuric acid 0^040 grm. 
 
 Hydrochloric acid 0*036 „ 
 
 Nitric acid °'°54 » 
 
 The specific gravity of an acid is determined by the hydrometer, and from 
 the specific gravity the percentage of pure acid can be obtained. 
 
(132) 
 
 
 CHAPTER XVI. 
 
 CHI.ORINK, CHLOR1DLS, AND CHLORIMETRY. 
 
 /^ HLORINE possesses the valuable property of destroying organic pigments, 
 ^^ and consequently is of use to the dyer as a bleaching agent. Under the 
 pressure of the atmosphere and at ordinary temperatures chlorine is a gas of 
 sp. gr. = i - 33. Its colour is a yellowish green. Its irritating odour is well known. 
 One volume of water absorbs 2*5 volumes of the gas, the result being known 
 as chlorine-water. The theory of its bleaching properties is based upon its 
 affinity for hydrogen, forming, with the hydrogen of the organic matter, 
 hydrochloric acid. Simultaneously, by the decomposition of the water con- 
 tained in the organic body, ozone is formed, and the latter oxidises the 
 colouring matter. Thus, in the case of bleaching flax and raw cotton, only 
 the colouring matter and not the cellulose is destroyed. 
 
 For purposes of transport it is usual to employ a combination of chlorine 
 with oxygen and a base, as a hypochlorite, and of these combinations we 
 shall speak presently. 
 
 The methods of preparing chlorine are very various. They may be divided 
 into two classes — those employing manganese and those which do not. The 
 latter it will be rn,ore convenient to describe first. At Mr. Tennant's works, 
 at Glasgow, Dunlop's process is employed, consisting in acting with sulphuric 
 acid upon a mixture of 3 molecules of common salt with 1 molecule of nitrate 
 of soda. Chlorine and hyponitric acid are evolved, the latter being absorbed 
 by passing the mixed gases through concentrated sulphuric acid. 
 
 Peligot's method consists in heating 3 parts of bichromate of potash and 
 4 parts of concentrated hydrochloric acid, to obtain a solution yielding, upon 
 cooling, crystals of bichromate of chloride of potassium, KCl,Cr0 3 ; and this 
 salt heated to no yields chlorine. 
 
 Messrs. MacDougal, Rawson, and Shanks decompose chromate of lime by 
 hydrochloric acid, with the formation of chloride of chromium, chloride of 
 calcium, and the evolution of free chlorine, according to the formula — 
 
 2CaCr0 4 +i6HCl = Cr 2 Cl6 + 2CaCl 2 +3H 2 + 6Cl. 
 The chloride of chromium may be precipitated with carbonate of lime, and 
 converted into chromate of lime by ignition. 
 
 M. Vogel decomposes chloride of copper by heat, the chloride being mixed 
 with sand, and heated in earthenware retorts to 250 . Chlorine is evolved, 
 and protochloride of copper remains, convertible into perchloride by treatment 
 with hydrochloric acid. 100 kilos, of cupric chloride yield 6 to 7 cubic metres 
 of chlorine. 
 
CHLORINE. 
 
 133 
 
 These are the principal methods without manganese. The action of sul- 
 phuric acid upon salt is supplemented by the addition of peroxide of manganese, 
 the result being the formation of sulphate of soda, sulphate of manganese, 
 and chlorine. In some cases, for the common salt is substituted hydrochloric 
 acid, to form sulphate of manganese and water, all the chlorine being 
 evolved. 
 
 Undoubtedly the most important plan yet adopted is that of Mr. Walter 
 Weldon. The process is performed in a series of vessels arranged at five 
 successive elevations, so that, after having been pumped up to the highest of 
 them, the liquor operated upon can afterwards descend to all the others by 
 its own gravity. The lowest of these vessels is a well, which is furnished 
 with a mechanical agitator. The slightly acid chloride of manganese liquor with 
 which the process commences runs from the stills in which it is produced into 
 this well, and is there treated with finely-divided carbonate of lime, the action 
 of which is facilitated by energetic agitation. When the neutralisation of the 
 free acid which is at first contained in this liquor, and the decomposition of 
 the sesquichloride of iron and sesquichloride of aluminium which are also at 
 first contained in it, are completed, the liquor is pumped up into settling tanks 
 placed nearly at the top of the apparatus, and known as " the chloride of 
 manganese settlers." It now consists of a quite neutral mixed solution of 
 chloride of manganese and chloride of calcium, containing in suspension 
 considerable quantities of sulphate of lime and small quantities of oxide of 
 iron and alumina. These solid matters deposit in the chloride of manganese 
 settlers, leaving the bulk of the liquor perfectly bright and clear, and of a faint 
 rose-colour. The next step is to run off the clear portion of the contents of 
 the chloride of manganese settlers into a vessel placed immediately below the 
 settlers, and called the " oxidiser." This is usually a cylindrical iron vessel, 
 about 12 feet in diameter and about 22 feet deep. Two pipes go down nearly 
 to the bottom of the oxidiser, — a large one for conveying a blast of air from a 
 blowing-engine, and a smaller one for the injection of steam. The latter is 
 for the purpose of raising the temperature of the contents of the oxidiser 
 when necessary to between 130° and 160 or 170 F. Immediately above the 
 oxidiser is a reservoir containing milk of lime. The oxidiser having received 
 a charge of clear liquor from the chloride of manganese settlers, and this 
 liquor having been heated up to the proper point, blowing is begun, and milk 
 of lime is then run into the oxidiser as rapidly as possible, until the filtrate 
 from a sample ceases to give a manganese reaction with solution of bleaching- 
 powder. A certain further quantity of milk of lime is then added, and the 
 blowing is continued until peroxidation ceases to advance. That point is 
 usually attained when from about 80 to 85 per cent of the manganese present 
 has become oxidised into peroxide. The contents of the oxidiser are now a 
 thin black mud, consisting of solution of chloride of calcium containing in 
 suspension about 2 lbs. of peroxide of manganese per cubic foot; these 2 lbs. 
 of peroxide of manganese being combined with varying quantities of protoxide 
 of manganese and lime. This thin mud is now run off from the oxidiser into 
 one or other of a range of settling-tanks (mud-settlers) placed below it, 
 and is there left at rest until it has settled as far as it will, usually until about 
 one-half of its volume has become clear. The clear part, consisting simply of 
 solution of chloride of calcium, is then decanted, and the remainder, containing 
 
134 
 
 DYEING AND CALICO PRINTING. 
 
 about 4 lbs. of peroxide of manganese per cubic foot, is then ready to be used 
 in the stills. There it reads upon hydrochloric acid, liberating chlorine, with 
 reprcdu&ion of exactly such a residual solution as was commenced with. 
 With that solution the round of operations is begun again ; and so on, time 
 after time, indefinitely. 
 
 The quantity of lime which has to be put into the oxidiser, before the filtrate 
 
 from a sample of its contents ceases to give a manganese reaction, varies very 
 
 considerably. Recently precipitated protoxide of manganese dissolves very 
 
 appreciably in neutral solution of chloride of calcium, its solution therein 
 
 comporting itself with reagents exactly like solutions of manganese salts. It 
 
 dissolves also in solution of oxychloride of calcium, — that is to say, in solution 
 
 of chloride of calcium containing dissolved lime ; its solution in oxychloride 
 
 of calcium nut giving the ordinary manganese reactions. Hence, even if all 
 
 portions of the lime added to the chloride of manganese in the oxidiser were 
 
 capable of acting on chloride of manganese equally readily, manganese could 
 
 not cease to be so in solution as to be detectable by ordinary reagents until 
 
 more than an equivalent of lime had been added,--until enough had been 
 
 added, that is to say, not only to decompose all the chloride of manganese, 
 
 but also to form a certain quantity of oxychloride of calcium. It is never the 
 
 case, however, that all portions of the lime used are capable of acting on 
 
 the chloride of manganese with equal readiness. The lime used always 
 
 contains a larger or smaller proportion of particles coarser than the rest, which 
 
 coarser portions cannot of course act so rapidly as the finer portions ; and as 
 
 the decomposition of the chloride of manganese requires to be completed as 
 
 quickly as possible, those portions of the lime which will not act upon it 
 
 instantly are scarcely allowed time to act upon it at all. These coarser 
 
 portions of the lime thus contribute very little to the decomposition of the 
 
 chloride of manganese, though they afterwards dissolve completely in the hot 
 
 solution of chloride of calcium, and then play their full part in the reactions 
 
 which take place during the subsequent blowing. The proportion of lime 
 
 which does not act on the chloride of manganese varies with the source of the 
 
 lime, and with the manner in which it is prepared ; so that the quantity of 
 
 lime which has to be added to a charge of chloride of manganese liquor in the 
 
 oxidiser, before the filtrate from a sample of the resulting mixture ceases to 
 
 become coloured on addition of solution of bleaching-powder, varies from 
 
 about 1*15 to 1*45 equivalents. The further quantity of lime which is added 
 
 after that point has been reached is now usually enough to raise the total 
 
 quantity to about 15 to i*6 equivalents, being from one-half to six-tenths in 
 
 excess of the quantity which actually takes part in the decomposition of the 
 
 chloride of manganese. 
 
 "The results," continues Mr. Weldon, "which we have latterly begun to 
 obtain with these proportions of lime are such as our previous experience had 
 not prepared us to expect. Until quite recently, our experience seemed to 
 show that whatever proportions of lime we might use in the oxidiser, we could 
 not obtain products containing less than an equivalent of base or bases per 
 equivalent of peroxide of manganese in them. Now, however, we are regu- 
 larly obtaining products containing only between o'o, and 0*7 equivalent of 
 base, and we have occasionally got down nearly to 0^5 equivalent of base. 
 With respect to the conditions which determine the formation of products 
 
CHLORINE. 
 
 *35 
 
 containing these low proportions of base, all that I can say at present is that 
 we have begun to make these produces, or at any rate to make them regularly, 
 only since we began to considerably increase the quantity of air blown in a 
 given time into an oxidiser of a given size. There can be scarcely any doubt 
 now that products containing at any rate something less than an equivalent of 
 base have been made occasionally, under special circumstances, from the very 
 beginning; but for a long time it was only so very rarely that we seemed to 
 get less than an equivalent of base, and the apparent proportion less than an 
 equivalent was always so small, that we put down the apparent result — a little 
 hastily, as it now appears — to errors of analysis. It is certain, however, that 
 products containing appreciably less than an equivalent of base have begun to 
 be made regularly only since manufacturers who had previously employed 
 one blowing-engine for the process began to use two engines, blowing with 
 both into the same oxidiser, and since other manufacturers began to work with 
 larger blowing-engines than had been used in the process before. 
 
 " All that I can learn with respect to the composition of the new produds 
 containing less than an equivalent of base tends to show, to my mind, that 
 there are manganites corresponding to nearly all the known carbonates. We 
 already knew of normal manganites, corresponding, say, to normal carbonate 
 of calcium, and of basic manganites, corresponding to Schindler's carbonate 
 of zinc and to Bonsdorf's carbonate of lead. I venture to believe now that 
 there are also acid manganites, corresponding to the bicarbonates, and that 
 sesquimanganites probably exist as well. 
 
 " That hydrated peroxide of manganese, or H 2 Mn0 3 , is as distinctly an 
 acid as H 2 C0 3 or H 2 S0 3 seems to me to be shown by the fact that if free 
 hydrated peroxide of manganese be boiled with an equivalent of protoxide of 
 manganese, a reaction takes place between the two bodies, the product of 
 which readion does not absorb oxygen on treatment with air. Of course, if 
 any free MnO remained after boiling the two bodies together, oxygen would be 
 absorbed on subsequent treatment with air. The product is, in fact, precisely 
 the same compound — ordinarily called ' sesquioxide of manganese,' and 
 written Mn 2 03 — as that which is produced by blowing air into a mixture of 
 protoxide of manganese and water, or in any other way exposing protoxide of 
 manganese, by itself, to the adion of the atmosphere at ordinary temperatures; 
 and its formation in the way just stated seems to me to be exactly similar to 
 that, say, of carbonate or of sulphite of calcium by the reaction of H 2 C0 3 or 
 of H 2 S0 3 upon CaO. Apart from its being thus formed by a reaction exactly 
 resembling the ordinary reaction of an acid upon a basic protoxide, that which 
 is ordinarily called sesquioxide of manganese is really manganite of hydrogen 
 in which H 2 has been replaced by Mn, and that it is thus properly manganite 
 of manganese, or MnMn0 3 , seems to me to follow from the circumstance that, 
 by whatever method this body may have been produced, on treating it with 
 solution of certain salts of other metals ordinary double decompositions occur. 
 Thus, MnMn0 3 + CuS0 4 give MnS0 4 + CuMn0 3 , and MnMn0 3 -f FeS0 4 give 
 MnS0 4 + FeMn0 3 . (This latter is a very unstable body, which soon undergoes 
 spontaneous change ; but that it is formed and exists for some time I believe 
 to be certain). Moreover, compounds in which the basic Mn of MnMn0 3 is 
 replaced by other metals can be formed, not only by the reaction of MnMn0 3 
 itself upon the salts of other metals, but also by the direct readion of nascent 
 

 J 3 6 
 
 DYEING AND CALICO PRINTING. 
 
 manganous acid upon protoxides of other metals. For example, as I stated 
 before, whereas if protoxide of manganese by itself be treated with air in 
 the wet way, only one-half of it undergoes peroxidation, the other half being 
 apparently required to furnish base to the half which becomes peroxidised, if 
 a mixture of protoxide of manganese and an equivalent of lime be treated 
 with air in the wet way, the whole of the protoxide undergoes peroxidation, 
 and the lime ceases to be capable of either reacting on chloride of manganese 
 or of dissolving in solution of chloride of calcium. Similarly, if protoxide of 
 manganese, suspended in solution of either baryta, strontia, soda, or potash, 
 be treated with air, baryta, strontia, soda, or potash goes out of solution, and 
 there is formed an insoluble compound containing one equivalent of man- 
 ganese, three equivalents of oxygen, and one equivalent of barium, strontium, 
 sodium, or potassium, as the case may be. 
 
 " With the existence and modes of formation of normal manganites of all 
 these metals we were formerly acquainted ; what is new is the apparent 
 formation, under the conditions of working on the large scale at which we 
 have arrived recently, of acid manganites, or double manganites of metal and 
 hydrogen. By far the greater number of batches containing less than an 
 equivalent of base which have been made as yet resemble in constitution one 
 or the other of the two representative batches. In one of the batches of the total 
 manganese operated upon 865 per cent had been peroxidised, and for each 
 equivalent of peroxidised manganese present there were o % 85 equivalent of 
 bases. Regarding the constituents of the batch, for convenience, as Mn0 2 , 
 MnO, and CaO, and considering the total manganese present as a thousand 
 equivalents, there were thus in this batch 865 equivalents of Mn0 2 , 135 
 equivalents of MnO, and 0-85 times 865, or 735 equivalents of total bases, 
 135 of which were MnO, the remaining 600 being CaO. Assuming that the 
 600 CaO were combined with 600 Mn0 2 , as normal manganite of calcium, 
 there remained 265 equivalents Mn0 2 and 135 equivalents of MnO, the pro- 
 portion of the former to that of the latter being very nearly two to one. 
 These figures I hold to show the existence in this batch of an acid manganite, 
 MnH 2 (Mn0 3 ) 2 , or a compound containing the elements of one of normal 
 manganite of manganese and one of manganite of hydrogen. In the other 
 batch, of the total manganese present 81*5 per cent had been peroxrdised, and 
 for each equivalent of peroxide present there were 0-885 equivalent of bases. 
 This batch, therefore, contained 815 equivalents of Mn0 2 , 185 equivalents of 
 MnO, and 536 equivalents of CaO. Assuming, as before, that all the lime 
 existed as CaMn0 3 , there were left 279 MnO a and 185 MnO. This is almost 
 exactly three of the former to two of the latter, suggesting the existence in 
 that batch of a sesquimanganite of manganese, containing the elements of 
 two of normal manganite of manganese with those of one of manganite of 
 hydrogen. In these batches it is only acid manganites of manganese that I 
 suppose to have existed ; but one or two batches have been made, containing 
 not much more than 0*5 equivalent of base, in which I believe that there 
 must also have been an acid manganite of calcium. It may be, of course, 
 that in all batches containing less than an equivalent of base a portion of the 
 manganous acid exists in the free state ; but I have not yet met with any 
 instance of a batch, the blowing of which I have known to have been con- 
 tinued until peroxidation had really ceased, and the proportion of base in 
 
CHLORttiE. 
 
 *37 
 
 which, while less" than an equivalent, was such that the batch could not have 
 consisted entirely of acid manganites, in which the peroxide remaining after 
 deduction of the quantity equivalent to the combined lime contained in the 
 batch was in any other proportion to the basic manganese contained in the 
 batch than either that of two equivalents to one or that of three equivalents 
 to two — a fact almost irresistibly suggestive of the two bodies being combined. 
 The circumstance, moreover, that under no known conditions can peroxide of 
 manganese be formed, by treating protoxide with air in the wet way, without 
 some portion either of manganese itself or of some other metal going simul- 
 taneously into combination as base, strongly indicates that only salts of 
 manganous acid can be formed in that way. 
 
 " The quantity of air which requires to be blown into the oxidiser per given 
 quantity of peroxide of manganese made varies with a considerable number of 
 conditions, but more especially with the depth of the charge operated upon, 
 and with the quantity of manganese contained in a given volume of it. 
 Within all practicable limits, increase of the depth of the column blown into is 
 equivalent to increase of the quantity of air blown ; and the more particles of 
 protoxide are contained in a given volume of the charge, the larger is the total 
 surface which they present for the air to act upon, and the greater is the pro- 
 portion of the total oxygen injected which becomes absorbed. The proportion 
 of the oxygen absorbed to the quantity blown in being of course greatest at 
 the commencement of the operation and afterwards continually diminishing, a 
 time at length arriving, if the blowing be continued long enough, at which no 
 more oxygen is absorbed at all, the proportion of the total quantity of oxygen 
 absorbed to the total quantity blown in is also considerably influenced by how 
 nearly to that point the operation be continued. As an illustration of what 
 is obtained on the large scale, it may be stated that a certain batch contained 
 1987 pounds of peroxide, reckoned as Mn0 2 , which was made in four hours, 
 by the injection of about 240,000 cubic feet of air, being at the rate of about 
 120 cubic feet of air for every pound of Mn0 2 made. 
 
 " The quantity of acid consumed per ton of bleaching-powder made by 
 means of manganite mud varies with the degree of care with which the process 
 is performed and with the general skill of the manufacturer, being in some 
 cases very considerably below the average quantity consumed in making a ton 
 of bleaching-powder by means of native manganese, while in other cases it is 
 scarcely at all below that quantity. I believe that a ton of bleaching-powder 
 is never made in this country, by means of native manganese, from less than 
 the acid from 60 cwts. of salt, and only rarely from less than the acid from 
 between 70 and 80 cwts. of salt. At least one manufacturer, however, whose 
 mud contains, as yet, by no means a minimum of base, and who at present 
 follows a method of treating the mud in the stills which is not quite the most 
 economical of acid, is consuming, per ton of bleaching-powder made by means 
 of manganite mud, only 170 cubic feet of acid at 24 Twaddell — a quantity 
 which I believe to be producible, in practice, from less than 48 cwts. of salt. 
 As what one manufacturer is doing can surely be done by all, when equally 
 familiar with the process, I venture to believe that a very considerable 
 economy of acid will eventually be realised by the process everywhere. 
 
 " The loss of manganese which occurs in the process at present varies from 
 about 4 per cent to about 10 per cent. The only unavoidable source of loss 
 
138 
 
 DYEING AND CALICO PRINTING. 
 
 is that constituted by the deposit of sulphate of lime and other matters which 
 form in chloride of manganese settlers. These deposited matters have to be 
 removed in the state of thin mud, largely mixed, that is to say, with solution 
 of chloride of manganese. Unless this mud be well washed after its removal 
 from the chloride of manganese settlers, and the washings be returned to the 
 process, the manganese lost with this mud amounts to fully 5 per cent, or even 
 more ; but by suitable washing the manganese thrown away with the mud 
 from chloride of manganese settlers can be reduced to below 2 per cent. The 
 only other sources of loss are — leakage of vessels, and the running away of 
 mud by careless workmen with the chloride of calcium solution from the mud- 
 settlers. The former of these sources of loss ought, practically, never to 
 exist, and the latter is now being eliminated at several works by the chloride 
 of calcium solution, instead of being run away diredlly from the mud-settler, 
 being run first into catch-pools, in which any mud which may be run off with 
 it from the mud-settlers is allowed to deposit. 
 
 " Beyond the sulphate of lime and other bodies which are deposited in the 
 chloride of manganese settlers, the only residual product of the process, and 
 the only other thing which has to be thrown away, is solution of chloride of 
 calcium. As this solution represents all the lime and all the limestone used 
 in the process, and two-thirds of the chlorine contained in the acid employed, 
 and as an industrial process is, of course, imperfect in proportion as anything 
 whatever which is manipulated in it has to be simply thrown away, and espe- 
 cially in proportion as its yield of the commodity, the production of which is 
 its sole object, falls below the total quantity contained in the materials used, I 
 have tried to use, in the oxidiser, magnesia instead of lime, afterwards decom- 
 posing, by heat, the resulting chloride of magnesium into magnesia, for use 
 over again, and hydrochloric acid. In that form, the process is capable of 
 yielding, undiluted with other gases, all the chlorine contained in the acid 
 employed, and, apart from mechanical loss, employs no materials which are 
 not used over and over again, excepting coal and air. This form of the process 
 has already stood the test of a certain amount of experience on the large 
 scale ; and I venture to believe that, when the time shall have arrived when it 
 will be desirable to obtain, from a given quantity of hydrochloric acid, more 
 chlorine than can be obtained therefrom by means of peroxide of manganese 
 recovered by means of lime, peroxide of manganese recovered by means of 
 magnesia will prove to be the reagent by which chlorine can be most econo- 
 mically manufactured." 
 
 The various hypochlorites nre easily prepared when the chlorine is provided. 
 The most important is that known as chloride of lime. 
 
 Chloride of lime, bleaching-powder (or more accurately, according to Fre- 
 senius, a mixture of 1 molecule of Ca(C10) 2 and 2 molecules of basic chloride 
 of calcium, CaCl 2 ,2CaH20 z + 2H 2 0), occurs in commerce as a moist white 
 powder, 1 part of which is soluble in 10 parts of water. As a bleaching agent, 
 the presence of an acid is required to develope its full properties — a matter of 
 advantage in Turkey-red dyeing in the production of white patterns by printing 
 on a thin paste of tartaric acid, the fabric being afterwards immersed 
 momentarily in a solution of bleaching-powder. For the acid, sulphate or 
 chloride of zinc may be substituted, the hypochlorous acid being set free, while 
 sulphate of lime and oxide of zinc are thrown down. 
 
CHLORINE. 139 
 
 In considering the constitution of bleaching-powder it may be useful to 
 record that, kept under pressure or in too tightly-closed cases, it is liable to 
 spontaneous decomposition and explosion, illustrated by the formula — 
 Ca(C10) 2 + CaCl 2 = 2CaCl 2 -i- 2 . 
 When chlorine is admitted to slaked lime, chloride or hypochlorite of lime 
 is almost immediately formed, but the formation is much retarded if an excess 
 of the gas be present. The theory of the formation is that some of the oxygen 
 of the lime combines with the chlorine to form hypochlorous acid, which in 
 its turn, combining with the undecomposed lime, forms hypochlorite of lime ; 
 and that another equivalent of the chlorine combines with the decomposed 
 lime or calcium to form chloride of calcium. A bleaching-powder so consti- 
 tuted should consist of — 
 
 Hypochlorite of lime 49-31 per cent. 
 
 Chloride of calcium 38-28 ,, 
 
 Water 12-41 „ 
 
 but such a verification of theory never occurs in samples of the commercial 
 product, the closest approximation being similar to the result of the following 
 percentical analysis: — 
 
 Hypochlorite of lime 26-72 
 
 Active chloride of calcium 20-72 
 
 Excess ,, ,, 4-79 
 
 Hydrate of lime 30-46 
 
 Water I 7'3 I 
 
 IOO'OO 
 
 Bleaching-liquor is similarly formed by passing chlorine gas into a solution 
 of lime. If we substitute for the lime a solution of caustic soda or potash, 
 the chlorides of these bases are obtained ; they are sometimes employed as 
 weak bleaching agents. 
 
 Solutions of hypochlorite of potash and hypochlorite of soda are known 
 in commerce as Eaux de Javclle and de Labarraque. Wilson's bleaching- 
 liquor is a solution of hypochlorite of alumina, obtained by mixing chloride 
 of lime with sulphate of alumina in solution. Ramsay's bleaching-liquor, a 
 hypochlorite of magnesia obtained by adding sulphate of magnesia to a 
 solution of bleaching-powder, is a very energetic preparation, and leaves the 
 fibre more soft and supple than the hypochlorite of lime. Varrentrap's 
 bleaching-powder is a solution of hypochlorite of zinc. 
 
 The testing of samples of bleaching-liquors or powders is necessary in order 
 to ascertain the percentage they will afford of active chlorine and hypochlorous 
 acid. The indigo-test is based upon the decolourising effect of chlorine upon 
 organic colouring matters. This test is, however, the most inaccurate, because 
 the chlorisatine resulting from the decomposition of the indigo, being in colour 
 yellow, combines with the indigo to produce a green colour, which admits of 
 little accuracy in noting the exact period of change. The indigo-test has 
 generally given way to the method invented by Gay-Lussac, which is based 
 upon the property possessed by arsenious acid in a solution of hydrochloric 
 acid of becoming oxidised to arsenic acid when in the presence of chlorine 
 and water. One equivalent of arsenious acid thus reacts with 2 equivalents 
 of chlorine and 2 equivalents of water to produce 1 equivalent of arsenic acid 
 
140 
 
 DYEING AND CALICO PRINTING. 
 
 and 2 equivalents of hydrochloric acid. Supposing, then, the equivalent of 
 arsenious acid to be represented by gg, while that of chlorine is 35*5, 99 grains 
 of arsenious acid will correspond to 71 (2 equivalents) of chlorine. It is clear, 
 then, for practical purposes there may be taken 139*44 grains of arsenious acid 
 as corresponding to 100 grains of chlorine. Therefore, if 139*44 grains of 
 pure arsenious acid be dissolved in 3 ozs. of pure hydrochloric acid, and the 
 solution diluted to 10,000 grains measure, each 1000 grains measure will 
 contain 13*944 grains of arsenious acid, equivalent to 10 grains weight of 
 chlorine. This is the arsenious acid test solution. To this solution is to be 
 added a few drops of sulphate of indigo, in order to afford an indication of the 
 point at which the bleaching effect of the chloride of lime solution predomi- 
 nates. The process of titration is proceeded with as in alkalimetry, and the 
 result obtained by a proportional equation. 
 
 With the description of another chloriinetric process wc shall bring this 
 division to a close. For this method it is necessary to prepare some iodide of 
 potassium-starch papers, by taking a clear solution of starch and dissolving 
 therein some iodide of potassium ; filter-paper may then be dipped into this 
 solution, and then cut into small strips. This paper, when prepared in this 
 manner, becomes coloured blue by contact with chlorine and hypochlorites. 
 
 The normal arsenious acid solution is prepared from finely-pulverised 
 arsenious acid dried in a desiccator. From this dried arsenious acid 4-95 grms. 
 are weighed out, and dissolved, in the presence of 10 grms. of carbonate of 
 soda, in distilled water, and diluted to 1000 c.c. A c.c. of this solution con- 
 tains therefore 0*00495 g rm - OI arsenious acid. 
 
 Iodine is very little soluble in water, and is best employed for this purpose 
 in the form of solution in iodide of potassium. There are to be weighed out 
 12*7 grms. of crystals of iodine, and these are to be rubbed down with 
 18 grms. of iodide of potassium, in a porcelain mortar, with the addition of 
 a little water. This solution should be diluted to 1000 c.c, and 10 c.c. of 
 this diluted solution should be capable of oxidising 1 c.c. of normal arsenious 
 acid into arsenic acid. 
 
 Estimation of the Chlorine in Chlorine-Water. 
 
 Two equivalents of chlorine are capable of oxidising 1 equivalent of arse- 
 nious acid to arsenic acid, so that 1 c.c. of the normal arsenious acid solution 
 corresponds to 0*00355 grm. of chlorine : 50 c.c. of the sample to be tested 
 are to be titrated with the arsenious test-solution until the iodide test-paper is 
 no longer coloured blue. The test may then be discontinued, or, for greater 
 accuracy, the solution may be titrated back with the normal iodine solution, 
 the number of divisions of the iodine solution employed being divided by 10. 
 An example will make the process clear. We have 50 c.c. of the chlorine 
 water to be tested, and we will suppose 34 c.c. of the normal arsenious acid 
 solution to have been employed in the titration, and 18*8 c.c. of the iodine 
 solution in the re-titration, this representing the excess of normal arsenious 
 solution employed. Dividing this number by 10, and deducting the result 
 1-88 from 34, we have 32*12 c.c. of normal arsenious acid solution really em- 
 ployed. This number multiplied by 0*00355 g' ves 0*114026 grm. chlorine. 
 The 50 c.c. of chlorine water contain, therefore, 0*114026 grm. of chlorine, and 
 
 from the equation — 
 
 50 : o* 1 14026 = 100 : x 
 
 we obtain a = o*22S per cent of chlorine. 
 
CHLORINE. 
 
 141 
 
 Estimation of Hypochlorites. 
 
 The hypochlorites are seldom pure, but contain, from the method of their 
 preparation, constituents which more or less directly bear upon the correctness 
 of the observation. Hypochlorite of lime contains besides, as we have 
 seen, chloride of calcium and hydrate of lime. The hypochlorites of potash 
 and soda contain carbonates and chlorides of the respective bases. 
 
 Two equivalents of chlorine correspond to 1 equivalent of hypochlorous 
 acid, or (2 equivalents of chlorine being equal to 71 parts of chlorine) to 71*5 
 parts of hypochlorite of lime, 74*5 parts of hypochlorite of soda, or 90-7 parts 
 of hypochlorite of potash. 
 
 In order to estimate the value of a hypochlorite of lime, 10 grms. of the 
 sample to be tested should be rubbed down with a small quantity of water, to 
 form a smooth milky fluid : this milk should be poured into a mixing beaker, 
 and the residue remaining in the mortar should be washed with water, and the 
 wash-water added to the contents of the beaker. The milky liquid should then 
 be diluted to 500 c.c. 50 c.c. of this solution should then be brought under the 
 burette containing the normal arsenious acid solution, which must be added 
 until the iodide test-paper is no longer tinged blue. Then the solution should 
 be titrated back with the normal iodine solution, until the blue colour is 
 re-established. The number of c.c. of iodine solution employed divided by 10, 
 subtracted from the number of c.c. of normal arsenious acid employed, will 
 give a difference which, multipled by 0*00355, produces the required weight in 
 grammes. For example, suppose 50 c.c. = 1 grm. of hypochlorite of lime, to 
 require 92 c.c. of the normal arsenious acid solution for the titration, and 
 18 c.c. of the iodine solution for the second titration; then 92—1*8 = 90*2 c.c, 
 and 90*2 x 0*00355 =0*32021 grm. of chlorine, or of hypochlorite of lime con- 
 taining 32*021 per cent of chlorine. 
 
 The applications of the salts not described in this section will be found 
 recorded during the subsequent pages of the work. 
 
(H2) 
 
 DIVISION II. 
 
 CHAPTER I. 
 
 THE GENERAL PRINCIPLES OF THE FIXATION OF COLOURING MATTER UPON 
 FIBROUS TEXTURES. CLASSIFICATION OF DYE-MATERIALS. 
 
 '"p HE substances employed industrially to impart colours to textile fabrics 
 are of very various origin and different characters. Some of them play 
 only a subsidiary part, and are removed as soon as the colouring-matter is 
 definitely fixed — such are, for instance, thickeners, acids used as discharges, 
 resists or solvents, oxidising and reducing agents, substances employed only on 
 account of their hygroscopic properties, and some others which, of great 
 utility, have their action unexplained. Other substances, again, concur either 
 wholly or partly to constitute the colour remaining upon the cloth. Indigotine 
 is integrally fixed, while acetate of alumina and chromate of potash are sub- 
 stances employed as agents for the fixing of madder-red and chrome-yellow, 
 deriving their powers from the alumina and chromic acid they contain. All 
 these substances are, therefore, dyes or tinctorial matters, because for the 
 production of madder-red alumina is as necessary as alizarine itself, 
 which is naturally of a pale yellow-red colour. It is clear, however, that 
 in a restricted sense alumina cannot be called a tinctorial or colour-giving 
 matter, considering that it does not impart to tissues, nor is itself possessed 
 of, any colour. Colours likewise exist that directly impart to cloth their own 
 tinge, such as indigotine, carthamic acid, bixine. There also belong to this 
 class the oxides of iron and chromium, and ultramarine. A rather too familiar 
 instance of the tinctorial power of oxide of iron occurs in the "iron-moulding" 
 of linen. But a large number of dyes require the intervention of a mordant. 
 When a substance is dyed red with madder the alumina is the mordant and 
 the alizarine contained in the madder the colouring matter ; whilst in the case 
 of chrome-yellow the chromic acid is the colouring matter and the oxide of 
 lead maybe called the mordant. Taking the widest limit of this view, it must 
 be admitted that the colour yielded by catechu is the result of the union of 
 catechine with oxygen, the latter acting really as a mordant. But the term 
 mordant is now limited in its application to substances in the solid state. 
 There must be no confusion between the colouring matters and mordants 
 of commerce, and the produce fixed upon the woven fabric ; madder, 
 
DYE MATERIALS. 
 
 143 
 
 for instance, is commercially a colouring material, and acetate of alumina 
 commercially a mordant, but the immediately effective colouring matter is 
 alizarine, and the active agent of the mordant alumina. The mode of action 
 of mordants is manifold as well as complex, and again differs for different 
 cases. The mordant sometimes serves to render the colouring matter 
 insoluble, and to fix it to tissues for which the colouring matter has itself 
 but little affinity. Again, the mordant may modify or entirely change the 
 shade of the colouring matter; or the mordant may simply render the dye 
 " fast," as it is termed, instanced by the peculiar action of fatty matter in 
 turkey-red dyeing. In another portion of this chapter we shall speak more 
 in detail of the nature and action of mordants. 
 
 Colouring matters may, then, be divided into two classes: — 
 
 1. Colouring matters that become fixed and exhibit their peculiar colour 
 without the application of an intermediate agent or mordant. 
 
 2. Colouring matters fixed by the agency of a mordant with which they 
 combine. 
 
 Aniline-red dyes wool and silk without the aid of a mordant, while it has not 
 the least affinity for cotton, hemp, or flax. Animal fibres combine chemically 
 with fuchsine and analogous colouring matters ; indeed, many animal sub- 
 stances themselves act as mordants. We have arrived at the conclusion, 
 therefore, that a woven tissue can be §aid to be dyed only when the dye resists 
 the action of water and of friction. The colouring matter must consequently 
 mechanically adhere to the fibre or be chemically incorporated with it. The 
 theory of the fixing of colouring matter cannot be reduced to a single principle, 
 since it varies as well with the nature of the colouring matter as with the 
 nature of the fibrous substance. An insoluble colouring matter can in no 
 case be deposited alone on the fibre, for the least friction would cause it to 
 become detached. When a very finely divided insoluble colouring matter is 
 mixed with a solution of gum or gelatine, or any other viscous material, and 
 is thus applied to a tissue, the thickener, when dry, will form upon the surface 
 of the fibre a kind of varnish, which will cause the powder to adhere tem- 
 porarily or until brought under the influence of water. Some kinds of mixed 
 gauze tissues not intended to be washed are coloured in this manner — too 
 often with poisonous compounds. Many of the finer tissues admit only of 
 this method of colouring, instanced in the case of mixed raw silk and cotton 
 fabrics. These fabrics are sometimes coloured with Scheele's green, and the 
 colouring matter becomes detached by friction. It is evident that if any sub- 
 stance can be found possessing the property of glueing, as it were, the 
 colouring matter to the woven tissue, then it is possible to fix colours other- 
 wise insoluble in neutral solvents. Such a substance we possess in albumen, 
 and from what has been said it will be readily understood that the property 
 possessed by albumen of coagulating at a high temperature greatly enhances 
 its practical value, because by its agency colours may be fixed under the action 
 of steam. 
 
 If it is found desirable to fix to cloth any insoluble substance otherwise 
 than by means of an agglutinative, it is then indispensable that it be first 
 dissolved, in order that it may thoroughly penetrate the pores of the fibre and 
 be uniformly divided. We have here to distinguish two cases which can 
 occur — 
 
i 4 4 
 
 DYEING AND CALICO PRINTING. 
 
 i. The insoluble substance may be only very weakly retained in solution by 
 its solvent, and the molecular attraction of the fibre may be stronger than 
 that of the solvent menstruum. In this case there will be precipitation of the 
 dissolved matter without any extraneous aid. This action is instanced with 
 an alkaline solution of reduced indigo in which cotton is immersed ; decom- 
 position and precipitation take place, and the dissolved (white) indigo is 
 attracted so strongly that the amount of indigo taken up increases with 
 time. According to M. Persoz, a solution of alumina with excess of base 
 cedes to cotton fibre its excess of alumina. 
 
 2. But if the affinity of the solvent for the dissolvedfmatter be greater than 
 that of the fibre it becomes necessary to employ means by which this resistance 
 may be overcome, and the colour precipitated in an insoluble condition upon 
 the fibre. 
 
 The explanations of the modes of action under these principles are very 
 many and various. According to some, the fixation of the insoluble colouring 
 matter is mechanical — the solid molecules being considered to have penetrated 
 the pores of the fibre by endosmose, and by becoming precipitated to have 
 lost their motive power. This theory, first promulgated by Hellot, le Pileur 
 D'Apligny, and Macquer, has been urged with great ingenuity and talent by 
 Mr. Walter Crum, with, however, essential modification of the erroneous views 
 of the previous theory. According to others, who have at their head M. Chevreul, 
 a true chemical combination takes place between the fibre and the colouring 
 matter. It does not appear possible to assimilate the dyeing of cotton by 
 means of indigo, oxide of iron, or oxide of chromium, &c, with a chemical 
 phenomenon of the same order as the union of oxygen and hydrogen, of 
 sulphur and iron, which takes place in definite atomic proportions, and after 
 which the constituents have entirely or partially lost their distinctive individual 
 characters. It is true there exists for the fibre a state of saturation beyond 
 which it is not capable of retaining a further quantity of colouring matter ; 
 but there does not appear to exist between the quantity of fibrous matter and 
 of colouring matter any atomic or relative proportion. On the other hand, 
 neither fibre nor colour loses after fixation any single distinctive quality that 
 it before possessed. 
 
 The colouring matter can be removed from the fibre to which it has been 
 fixed by any solvent which would act upon it in its free state, leaving the fibre 
 perfectly intact. This would show at most only a molecular attraction similar 
 to that exhibited by carbon and many other porous bodies. Should it be 
 urged that the precipitation of indigo or of basic alumina is evidence that 
 there exists in cloth fibre a chemical affinity capable of overpowering another 
 similar affinity, it may be answered that the force of diffusion alone is capable 
 of determining the dissociation of compounds, the elements of which exert 
 powerful mutual attraction. For an instance may be cited the combination 
 of sulphuric acid and sulphate of potash in the bisulphate of that base. 
 
 Summing up our evidence, it appears that the fixing of colouring matters 
 and insoluble substances upon fibre may be best considered from the point of 
 view taken by Mr. Walter Crum. It may be added that molecular attraction 
 aids permanent adhesion. The theories propounded by M. Persoz and 
 Mr. Walter Crum are not diametrically opposed, as would appear at first sight; 
 indeed, it might be urged that their views are compatible. The essential 
 
DYE MATERIALS. 
 
 145 
 
 difference may be thus shortly stated. M. Persoz holds that the colour is 
 fixed to the surface only of the fibre ; Mr. Walter Crum thinks the fibre to 
 be perfectly permeated by the colour. No other portion of our subject is so 
 difficult as the one upon which we are now engaged, and none so little re- 
 munerative, for were our knowledge precise and complete upon this point the 
 gain would not be great. 
 
 The practical view of the question leads to the following considerations : — 
 A mordant is a substance which can exert an affinity for the fibrous material 
 to which it is applied, at the same time possessing an attraction for colouring 
 matters. Mordants are not very numerous, and the class may be subdivided 
 into mordants proper and mordants of a dubious nature. The first division 
 contains those metallic salts whose oxides appear to effect an intimate 
 chemical union with the fibre and colouring matter. The second division 
 includes a number of substances, which, possessing some affinity for colouring 
 matter, do not appear to combine with the cloth in a chemical, but rather 
 to adhere to it in a mechanical manner. Under the first division may be 
 mentioned the so-called mineral mordants, salts of iron, zinc, alumina, tin, 
 and copper; to the second division belong some vegetable and animal 
 matters, as galls, oils, albumen, caseine. With wool, silk, hair, skin, horn, 
 and bone there exists naturally an affinity for colouring matters, but not 
 to an extent sufficient to yield general good results. There are only a few 
 colours that can combine with either vegetable or animal tissues without the 
 aid of a mordant, and of these the majority are much improved both in 
 brilliancy and fastness by the presence of a mordant. The colouring 
 matters of madder, logwood, fustic, and many other dyes are by themselves 
 capable of imparting a feeble colour to unmordanted calico, but with the 
 assistance of mordants they communicate fast and brilliant hues. Although 
 several colouring matters can impart their shade to woollen fabrics without 
 a mordant the hue is poor and feeble, lacking lustre, and not possessed 
 of any great stability. The colouring matters of indigo, safflower, and 
 annatto impart colour to cotton fabrics without the agency of a mordant, 
 which does not much improve the depth and colour; and for woollen tissues 
 may be added picric acid, archil, and many of the aniline colours. Silk 
 behaves very similarly to wool, and with the exception of indigo — a dye sui 
 generis — all the colours are loose and unstable. There are certain conditions 
 absolutely necessary to the constitution of a true mordant. The first is 
 solubility. Unless the metallic oxide to be used as a mordant can thoroughly 
 permeate the fibres, the colour will not resist washing, at least with soap and 
 hot water; and such complete permeation cannot take place except the 
 mordant be in the condition of a clear solution. The property of becoming 
 insoluble is the second essential of a mordant; it is apparent that if a mordant 
 be carried into the pores of the fibre simply on account of its solubility, that 
 the same reason would cause its return, unless means were taken to fix it per- 
 manently upon the spot to which it has penetrated. This insolubility is 
 obtained in various ways. The metallic oxide is combined with a volatile 
 acid, such as acetic acid, which, after volatilisation, leaves the oxide in- 
 solubly fixed in the fibre ; this method is most generally employed. Or the 
 oxide may be combined with a non-volatile acid, the acid being removed by 
 chemical means, such as an alkaline bath, exposure to vapours of ammonia, 
 
 L 
 
146 
 
 DYEING AND CALICO PRINTING. 
 
 &c. In the case of nitrate of iron, a salt is chosen which holds one part of 
 its oxide in a comparatively loose state, and, when diluted with water, allows 
 the feeble affinity of the fibre to remove it from the acid. A similar process 
 takes place with alum when a portion of the acid has been removed by 
 salts having an alkaline reaction. 
 
 The vegetable and animal mordants differ in their method of adhering to 
 the fibre. Oil, as employed in Turkey-red dyeing, undergoes a change by 
 exposure to the air, which renders it insoluble and irremovable by ordinary 
 agents. Albumen and similar substances possess a mechanical affinity for 
 the cloth ; they are applied in the soluble state, and become insoluble by heat, 
 or some other agent which coagulates them. They embrace the fabric in a 
 reticulation of fibres, and may be considered as rather holding to the surface 
 than us retained in the interior of the fibre. 
 
 There now arises the question, what is the nature of the combination 
 which takes place between the mordant and the fibre ? No direct nor positive 
 answer can be given, for the question is involved in doubt and controversy, 
 while the evidence on the various views is so inconclusive that no satisfactory 
 result can be arrived at. The insoluble particles of the mordant may be re- 
 tained simply in a mechanical manner by the fibre, which is supposed to be 
 hollow, and to act the part of a trap; or the fibres may be porous, and the acid 
 solutions penetrating the pores leave their oxides in contact with the walls of 
 the cells, from which they cannot escape, either by reason of the narrowness of 
 the cells or some supposed conformation of the metallic oxide. The mordants, 
 again, separated by more powerful chemical agents, or through destruction 
 by time, may form a chemical combination with the matter of the fibre. Or the 
 fibre may possess some active power of adhesion on its exterior walls for the 
 metallic oxides, and they may be held together by virtue of the power of contact. 
 All these theories are held, and the sum of the evidence that can be drawn 
 from chemical or microscopical observations does not bear more on one side 
 than on the other. In the absence of any satisfactory scientific account, we 
 may undertake the practical supposition that the particles of mordants are 
 held by the fibres in a state of chemical freedom, capable of exerting all their 
 affinities, and drawing to themselves those substances for which they have an 
 attraction. 
 
 The affinity which the mordants have for the colouring matter is undoubtedly 
 of a chemical nature. A given quantity or strength of mordant can combine 
 with only a certain amount of colouring matter to produce a certain shade, 
 and, as is the case in most chemical combinations, the colour of the resulting 
 compounds bears no necessary resemblance to that of the constituents. The 
 shades of colour which any dye-stuff can give differ for each mordant, and for 
 various strengths of the same mordant. The same colouring matter will yield 
 Bhades that appear quite opposite in their nature, as, for instance, madder, 
 which with weak alumina mordants gives pink, with strong red ; with weak 
 iron mordants, lilac or violet, with strong black colours ; while a mixture of 
 iron and alumina mordants yields various shades of chocolate. 
 
 A giveft mordant has not the same properties upon all kinds of fibre. Tin 
 mordant, so extensively employed in woollen dyeing, and yielding fast colours, 
 is a very feeble mordant on cotton, and never gives colours comparable for 
 
DYE MATERIALS. 
 
 147 
 
 fastness with those of alumina or iron. On the contrary, iron mordants are 
 very difficult to employ on woollen fabrics. 
 
 A mordant may be applied to a cloth in three ways with regard to the 
 colouring matter : — 
 
 1. The mordant maybe applied before the colouring matter; and this is 
 usually the case in calico printing, for dyed goods, and frequently in piece 
 dyeing. 
 
 2. The mordant may be applied after the colouring; this process is generally 
 adopted in piece dyeing, where the pieces are first passed through the extract 
 of the colouring matter, and then through the metallic mordant. 
 
 3. The mordant and colouring matter may be applied simultaneously; this 
 takes place with many colours in dyeing, and with all steam and spirit colours 
 in calico printing. 
 
 In the first case, where the mordant is applied before the colouring matter, 
 the method is necessary in printing designs upon the fabric to be dyed. It is 
 essential that the mordant should be thoroughly fixed upon the cloth before 
 passing the latter into the dye-beck, because a design requires that there 
 should be at least two shades of colour, one of which may be the white of the 
 cloth, and it is to be easily conceived that if the mordant were loose or floating 
 about in the dye-beck it would attach itself indiscriminately to all parts and 
 destroy the design. The fixing of the mordant necessitates several processes 
 unknown in piece dyeing. 
 
 In the second case, that of applying the colouring matter before the mordant, 
 the method is employed with only self-coloured fabrics, and has arisen from 
 motives of convenience and economy. It usually happens that the mordant 
 is much cheaper than the colouring matter in regard to the quantities employed, 
 and the colouring matter can be more completely utilised by having the 
 mordant in excess. 
 
 The method of using the mordant and colouring matter together is one of 
 limited application, because in the majority of cases insoluble lakes are formed, 
 not well adapted to give good and fast colours. In calico printing it is 
 possible to use the colouring matter in a concentrated state and in combination 
 with acids and other matters, which keep it and the mordant in a state of 
 solution until the affinities of the cloth come into play, assisted also by artificial 
 means, as steaming, passing through alkaline baths, &c, to cause the formation 
 of an insoluble compound and the adhesion of both mordant and colouring 
 principle to the cloth. 
 
 In practice, colouring matters are classed according to the process by which 
 they are fixed, as — dye colours, steam colours, and colours otherwise applied. 
 This classification is arbitrary and vague. The following classification, although 
 it possesses but few chances of general acceptance in practice, has the ad- 
 vantage of being rational : — 
 
 A. Mechanical fixation of insoluble colours. 
 An insoluble colouring-matter is applied in the state of a very finely 
 divided powder, and is fixed upon the fabric by means of a substance 
 which becomes solid and generally at the same time insoluble. 
 Examples are given in the dyeing of tissues with ultramarine, Guignet's 
 green, and lamp-black, fixed by means of albumen, gluten, caseine, or 
 shellac. 
 
 L 2 
 
>pl5*r- 
 
 148 
 
 DYEING AND CALICO PRINTING. 
 
 B. The colouring matter combines with the fibre ; the colour is the result of 
 
 this union. 
 This simple dyeing maybe subdivided into: — 
 
 a. The woven fabric or fibre is immersed in a bath or solution of 
 colouring matter at the ordinary, or at a higher, temperature. The 
 fabric gradually draws the colouring matter from the bath by a 
 true chemical attraction. In this manner a uniform colour is 
 imparted to the whole tissue, unless a resist had previously been 
 printed on ; or, the uniform colour is subsequently discharged in 
 certain patterns by means of acids and other reagents. Examples : 
 The dyeing of woollen and silken fabrics with aniline colours, 
 sulphindigotic acid, picric acid, orceine. Vegetable fibre cannot 
 be dyed by this method. 
 
 p. The colouring matter is printed on the cloth after mixture with a 
 thickener, and the colour is subsequently developed by exposure 
 to the heat of steam. 
 
 C. The colouring matter becomes incorporated, but not chemically combined, 
 
 with the fibre. 
 
 I. The fixation of colour by surface attraction at the moment of 
 
 separation from the solvent, as with carthamine ; or precipitation 
 due to the action of porosity and surface attraction upon a colour 
 which is only feebly united to a solvent, as with indigo, annatto, &c* 
 
 II. Fixing colouring matter properly dissolved by means of the chemical 
 
 attraction exerted by a previously mordanted fibre. The difference 
 between this method and that described under B is, that in con- 
 sequence of the absence of any affinity between the colouring matter 
 and the fibre, the latter has been prepared or provided with an 
 insoluble substance, which possesses the power of combining with 
 the colouring matter, and of fixing it firmly to the fibre. Mordants 
 do not act in this manner only, but exercise as well the function of 
 varying and regulating the shade and the depth of colour. For 
 example, when non-mordanted wool is steeped in a solution of 
 cochineal, it will assume a claret-red or a grenadine-red colour; 
 but if the wool has previously been mordanted, it will assume a 
 bright scarlet. Cotton fabrics previously mordanted with iron or 
 alumina mordants will, on immersion in a madder bath, exhibit a 
 violet, Mack, red, pink, or chocolate colour, according to the nature of 
 the mordant and its strength. 
 
 III. Fixing by oxidation. The colouring matter, or rather the matter 
 capable of development as a colour, is applied to the fibre in solution 
 (either by immersion or by printing), and is next submitted to an 
 oxidation which precipitates or fixes and as well developes the colours. 
 Examples : the fixing of catechu, logwood, aniline black. The oxi- 
 dation is induced — 
 
 a. By exposure to air, with orwithout addition of any alkaline substance. 
 
 * The development of the colour requires, in the first instance, a subsequent oxidation, 
 which does not, however, render the colour more durable, nor prevent re-solution in any 
 menstruum similar to that of the first solvent. 
 
DYE MATERIALS. 
 
 149 
 
 b. By passing the tissue through any bath or solution containing an 
 
 oxidising material, such as a chromate. 
 
 c. By the introduction into the colouring mixture which is to be 
 
 printed on the cloth of some oxidising substance, which on ex- 
 posure to an elevated temperature gives off oxygen. 
 
 IV. The colour is dissolved in a suitable solvent, which is capable of 
 being volatilised by exposure to air and heat. This method is 
 employed in the fixing of the acetates of iron and alumina, for 
 example, and is sometimes accompanied by oxidation. Steam-heat 
 is generally used to effect the volatilisation. 
 
 V. The colour is formed upon the fibre by double decomposition or 
 
 displacement effected by means of two salts, or a salt and an alkaline 
 hydrate, or an alkaline carbonate. One of these compounds is 
 applied to the fibre in solution, while the other is dissolved in a 
 suitable fluid, and the fibrous material is passed through this solution. 
 Examples : fixing the oxides of iron, chromium, copper, manganese, 
 &c. This process also serves for the fixing of certain mordants, and 
 is employed in many cases with acetate of alumina mordants in 
 conjunction with the dung-bath. Oxidation is sometimes necessary 
 at a subsequent stage for the development of the colour. 
 
 VI. The constituent elements of a colour are presented to the fibre in 
 solution by chemical means, and in such a manner that — either under 
 the subsequent influence of moisture and heat or by lapse of time — 
 they unite to form an insoluble and adhesive colour. Under this 
 head may be included the dissociation of the ferro- and ferri- 
 cyanhydric acids by the influence of heat; the result of such 
 dissociation is subsequently oxidised to obtain a deposit of Prussian 
 blue. 
 
 Notwithstanding the many subdivisions of our classification, there are some 
 cases to which it is not applicable. To these belong those instances of mul- 
 tiple reactions, or of special agency, which will need presently a more 
 detailed treatment. 
 
 The colouring materials which we shall pass in review may be divided into 
 two groups, viz. — 
 
 Mineral Products, and 
 Organic Substances. 
 
 Among the members of the latter group we shall meet with a large number 
 of substances of vegetable and animal origin which have not been reproduced 
 artificially, and the constitution of which is imperfectly known, exhibiting no 
 other relation than that of similarity in colour. Others, again, have been re- 
 produced artificially, and are chemically well defined. 
 
(15°) 
 
 CHAPTER II. 
 
 MINERAL PIGMENTS. 
 
 X X 7E shall under this head have occasion to revert to some mineral salts, 
 which we have treated elsewhere with other views ; the re-statement 
 here is necessary when we specially regard the mineral as a pigment. 
 
 Every mineral colouring matter that is insoluble in water, and reduced to 
 an impalpable powder, can be applied to woven tissues by means of plastic 
 substances, such as albumen. Every mineral colouring matter insoluble in 
 water, and capable of development upon textile fabrics by soluble substances 
 (that is to say, by precipitation), can be employed in the processes of dyeing 
 and printing. Practically, however, the number of mineral pigments is 
 limited. Various reasons can be given for the large number of exceptions. 
 Leaving out of consideration the question of cost, there are such desiderata 
 as brilliancy, resistance to the influence of light, atmospheric and chemical 
 action, difficulties in fixing certain colours, and, finally, the danger of poisoning 
 as a consequence of the use of certain pigments. As mineral colours vary- 
 largely in composition and character, it will be unsatisfactory to give a general 
 review of their properties, but will be better to treat them specifically. As to 
 classification, the pigments may be separated into as many divisions as there 
 are colours in the spectrum, and further into groups according to their chemical 
 relations. The means and methods employed in fixing these materials upon 
 woven tissue will be separately described for each particular substance. 
 
 WHITE COLOURING MATTERS. 
 To these belong, in a very limited sense, — 
 
 Chalk, or Carbonate of Lime. 
 
 Used as an oii-paint for in-door work, and as a watc-colour when mixed 
 with gelatine. Chalk is sometimes employed to dilute other pigments, — that 
 is to say, to modify the shade, as with chrome-yellow and orange, ultramarine, 
 and Brunswick green. Prepared chalk is used in manufacturing chemistry for 
 the purposes of saturating acid fluids. It is not used as a pigment in dyeing 
 or printing. 
 
 Sulphate of Lime, or Gypsum. 
 
 Perfectly white plaster-of-paris (so called because the geological formation 
 upon which Paris stands is very rich in gypsum) is of only limited use as a 
 paint in the manufacture of paper-hangings, being then mixed with gum-water. 
 It is not employed as an oil-colour, and does not find any application in 
 pigment-printing. 
 
SULPHATE OF BARYTA. 
 
 *5* 
 
 Sulphate of Baryta. 
 
 This is a widely distributed mineral, and often occurs in a perfectly 
 pure white state. It is, for all practical purposes, insoluble in water and 
 acids, and is not acted upon by sulphurous emanations. In hue it is of 
 dazzling whiteness, especially when amorphous. It is a perfectly innocuous 
 pigment. Its great defect is that it covers badly ; in order to reduce to a 
 lighter shade of blue a certain weight of ultramarine, one part of white-lead 
 has the same effect as 5 parts of powdered native sulphate of baryta. The 
 artificial sulphate, especially that prepared by M. Kuhlmann's method, covers 
 very well, being obtained in an amorphous state. Chemists know that when 
 sulphate of baryta is precipitated from hot, and not too concentrated, solu- 
 tions, it assumes a crystalline appearance, and admits more readily of filtration. 
 White-lead, neutral carbonate of lead, also covers badly, as a consequence of 
 its crystalline condition, whereas the white-lead of commerce, being a basic 
 carbonate, is purposely prepared in an amorphous stale. It is the state of 
 aggregation, not the chemical composition, which influences what is termed 
 " covering power." Sulphate of baryta is not used as a pigment, except ft r 
 reducing the shade of other colours. White native substances, as pipe-clay, 
 kaolin, and similar aluminous minerals, and magnesian minerals, are not used 
 as pigment colours. 
 
 We have already referred to the use of aluminous and magnesian 
 minerals as thickeners, and it may be stated, in passu, that French chalk — 
 chiefly a silicate of magnesia — is employed in dressing and finishing calicoer. 
 Zinc-white, anhydrous oxide of zinc, is occasionally used in pigment- 
 printing, not, however, by itself, but as a diluent to reduce the depth of 
 shade of high- or dark-coloured pigments. 
 
 Among the substances applied to woven tissues, by the same or similar 
 means as pigment colours, should be mentioned the two metals, silver and 
 tin. The former is employed as silver-leaf, but, on account of its extraordinary 
 sensitiveness to the action of sulphurous emanations, the other metal, tin, is 
 preferred. Tin prepared in a very finely divided state is known commercially 
 as argentine, and is obtained in this form by precipitation of a slightly acid 
 solution of one of its protoxide salts by means of zinc. The tin solution 
 should be very dilute, and only very slightly acid ; the quantity treated at one 
 operation should be comparatively small. The following arrangement is 
 often employed : — Into cylindrical vessels of glazed earthenware, capable of 
 holding 12 litres (2 J gals.) each, is poured 8 to 10 litres (i£ to 2 gals.) of 
 solution of chloride of zinc at 10° to 15° Baume, to which is added 4 to 
 7 grms. (62 to 108 grs.) of tin-salt, known as crystals of tin, protochloride of 
 tin. Pieces of sheet zinc are then placed in the vessels, and when the reaction 
 has ceased the fluid and the precipitated metal are poured upon a clean silken 
 sieve. To the filtrate tin-salt is again added, and the operation repeated. 
 The precipitated metal is collected upon a filter, washed with water, dried at 
 a gentle heat, and passed through a fine silken sieve, to separate the most 
 finely divided metal. The metal is applied to the woven tissue by mixing 
 about 360 grms. (5544 grs.) with a litre of an ammoniacal solution of caseine. 
 The printing is effected by blocks or rollers, and a metallic lustre is developed 
 by heavy calendering and hot-pressing machines. Argentine effects have 
 
152 
 
 DYEING AND CALICO PRINTING. 
 
 also been produced by a totally different process. Solutions of the more 
 easily reducible metals, such as silver, lead, tin, bismuth, &c. T free from excess 
 of acid, were mixed with suitable reducing agents, such as aldehyde, methylic 
 spirit, and thickened with glucose. This mixture being printed upon the 
 fabric, a pattern was brought out in reduced metal. The ease with which 
 such delicate metallic films were acted on by sulphurous fumes present in the 
 atmosphere caused the goods soon to become very unsightly, as the process 
 is, for the present, in abeyance. It so happens that with the exception of 
 gold, which is too costly for articles of common consumption, the more 
 readily reducible metals have all a strong affinity for sulphur, by which they 
 are blackened. A practicable method of depositing, e.g., aluminium upon 
 silk or worsted goods, would be of great value. 
 
 RED MINERAL PIGMENTS. 
 Of red pigments minerals yield — one iodide, that of mercury ; three sul- 
 phides, viz., cinnabar or vermillion, the sulphide of mercury, — antimonial 
 vermillion, the tersulphuret of antimony,— and realgar, or the bisulphide of 
 arsenic. Among the oxides and derivatives we have — red-lead, or minium, a 
 peculiar oxide of lead ; English red peroxide of iron, red ochre ; suboxide of 
 copper ; the red oxide of tin, a modification of oxide of tin ; purple of Cassius ; 
 chromates of mercury and silver ; and subchromate of lead. None of these 
 or any other red mineral pigments are suitable for use on the large scale, 
 owing to their high price, and in some instances to the fact that they have a 
 great tendency to subside from the fluid in which they are suspended. 
 
 Bi-iodide of mercury yields a very rich scarlet, easily formed by the union 
 of iodine and mercury, or by double decomposition between a soluble iodide 
 and a solution of corrosive sublimate. 200 grms. of mercury are triturated 
 with 254 grms. of iodine, with the addition of a little alcohol ; or a solution of 
 corrosive sublimate is precipitated with iodide of potassium, or, more 
 economically, with iodide of iron produced by the action of iron on iodine in 
 the presence of water. 
 
 The fixation of the colouring matter upon cotton tissues is a simple 
 operation, but as the colour is very fugitive it is in very little request. 
 
 Cinnabar, vermillion, or sulphide of mercury, is formed artificially by a dry 
 or wet process, but a cinnabar which occurred native was known in Pliny's 
 time by the term minium. In the former process, 540 parts of mercury and 
 75 parts of sulphur are intimately combined to form a black powder, which is 
 introduced into iron vessels, and exposed to sufficient heat to fuse the mass. 
 The fused mass, when cool, is broken up, and introduced into loosely-covered 
 earthenware vessels, heated on sand-baths ; when sublimed the mass is pul- 
 verised, the result being a powder of a cochineal-red colour. Vermillion is 
 obtained by the wet process, by precipitating a solution of corrosive sublimate 
 in ammonia with a solution of sulphur in sulphide of ammonium ; or, according 
 to Dr. Von Martius, by agitating 1 part of sulphur, 7 parts of mercury, and 2 
 to 3 parts of a concentrated solution of liver of sulphur. M. Brunner pre- 
 pares a vermillion of the highest order of brilliancy by mixing 114 parts by 
 weight of sulphur and 300 parts by weight of mercury, with the addition of a 
 small quantity of caustic potash solution. This mixture is then treated with 
 a solution of 75 parts caustic potassa in 400 parts of water, and heated on a 
 
RED MINERAL PIGMENTS. 
 
 153 
 
 water-bath to about 45 C. After some hours the mixture acquires a scarlet 
 colour, and is then collected on filters, washed, and dried. The dried powder 
 is the vermillion of commerce. 
 
 The annexed specimen of vermillion-red we owe to the kindness of Mr. 
 Walter Crum, of the Thorniebank Print Works, Glasgow. It is produced by the 
 following process: — 5 lbs. of vermillion are mixed with 1 gallon of thickening; 
 the colour is then printed on the fabric, which is dried and steamed for one 
 hour. The thickening consists of a mixture of solutions of gum-dragon and 
 egg-albumen. These may be in different proportions, according to the degree of 
 fastness required. The more albumen used the faster will be any pigment or 
 paint colour. The gum-dragon solution is used in the proportion of \ to f lb. 
 per gallon of colour, and the albumen to the amount of 4 lbs. in the gallon of 
 colour : these proportions yield the fastest colour that is prepared. 2 lbs. of 
 albumen will give a moderately fast colour. 
 
 Vermillion Red. 
 
 Oxysulphuret of antimony, antimony cinnabar, or antimony vermillion, is a 
 similar compound to vermillion. It may be prepared on the large scale by the 
 following process: — Black sulphuret of antimony is calcined in a current of 
 air and steam, with the view of forming antimonic oxide and sulphurous acid, 
 the latter being employed for the preparation of dithionite of calcium from 
 soda-waste. The antimonic oxide is dissolved in hydrochloric acid. Large 
 wooden vessels, heated by steam-pipes, are nearly filled with a solution of 
 dithionite of calcium, and the protochloride of antimony is added gradually, 
 the liquid being stirred and heated to about 60° C. After the reaction has 
 ceased and the precipitate subsided, the latter is washed and dried at a tem- 
 perature under 50 C. Mixed with water or a solution of gum, the colour 
 appears very dull ; but as an oil-colour it possesses the most intense brilliancy. 
 Recipes for its application to printing have not been given. 
 
 Of the other red pigments, of very limited application in printing, we need 
 not speak in detail. 
 
HHHBHBBMHHHI^WBBHM 
 
 154 
 
 DYEING AND CALICO PRINTING. 
 
 YELLOW MINERAL PIGMENTS. 
 
 Of these we have the following : — Two iodides ; that of lead and the yellow 
 iodide of mercury. .Sulphides: orpiment, a peculiar sulphide of arsenic; 
 sulphide of cadmium ; the yellow-orange sulphide of antimony; and bisulphide 
 of tin. Oxides : hydrated oxide of tin ; crocus martis, a yellow hydrated 
 oxide of iron; massicot, oxide of lead; and oxide of uranium. Salts: Naples' 
 yellow, an antimoniate of lead ; uranates of soda and potash ; the insoluble 
 chromates of lead, bismuth, zinc, baryta, strontia, and lime; Cassel yellow, an 
 oxychloride of lead ; antimony yellow, an intimate mixture of the oxychlorides 
 of lead and bismuth and of antimoniate of lead. Metals: gold; and so-called 
 Dutch gold, an alloy of copper and zinc and of copper and tin, manufactured 
 chiefly at Nuremberg, in Bavaria. 
 
 This list contains a large number of mineral yellows employed exclusively 
 as oil-paints ; others may be fixed to woven tissues by the aid of plastic sub- 
 stances ; and, finally, the list includes the peculiar class of colours which 
 admit of direct precipitation upon the fabric. These are the insoluble chrome 
 colours, produced by an application, first, of subacetate of lead, and subsequent 
 immersion in a bath of neutral chromate of potash. 
 
 In the year 1820 the use of chromate colours was first attempted by 
 M. Lassainger. He steeped skeins of prepared or de-gummed silk in a 
 weak solution of subacetate of lead for about two hours. The silk was then 
 washed in clean cold water, and immersed in a dilute solution of neutral 
 chromate of potash. Upon this principle is based the application of the 
 soluble chromates in dyeing and calico printing. These colours are readily 
 detected by their property of becoming tinged a deeper orange by the action 
 of ammonia and of lime water, while acetic or citric acids restore the yellow 
 colour. Alkalies and strong hydrochloric acid permanently destroy these 
 colours. 
 
 The subjoined specimen of chrome-yellow or canary-yellow, printed upon 
 cotton by Messrs. Walter Crum and Co., is an illustration of the use of 
 chromate of lead. The colour is produced upon the cloth by the following 
 process: — 24 ozs. of white sugar of lead are dissolved in each gallon of water, 
 and thickened with 4 lbs. of British gum. This solution is printed on to the 
 cloth, which is then dried and passed for two minutes through a cold bath of 
 bichromate of potash and common salt containing 6 ozs. of bichrome 
 and 24 ozs. of salt to the gallon. The cloth is finally well washed and dried. 
 
 Another shade of yellow may be obtained on yarn by a treatment which is 
 chemically the same. 25 lbs. of cotton yarn are run through a bath of 2 lbs. 
 of sugar of lead for twenty minutes ; then through a weak lime water bath. 
 The yarn is removed from the lime bath at the end of five minutes, wrung out, 
 and passed through a cold bath of 1 lb. of bichromate of potash and 1 lb. of 
 hydrochloric acid. 
 
 If buff may be considered a shade of yellow, we may here detail how the 
 colour known commercially as iron-buff is produced. This colour is illustrated 
 in the subjoined specimen of printed cloth, likewise obtained from the same 
 distinguished firm. 
 
 There is first prepared a " standard liquor," from which in several pro- 
 portions with the thickening almost as many shades can be obtained. 4 lbs. 
 of copperas or sulphate of iron are dissolved in each gallon of water, to which 
 

 YELLOW MINERAL PIGMENTS. 
 
 155 
 
 Chrome- or Canary-Yellow. 
 
 are added 2 lbs. of acetate of lead, the mixture being stirred until solution is 
 complete. The deposit is allowed to subside, and the clear liquor, which 
 should stand at 27 Tw., strained off. This standard liquor is, in the shade 
 given in the specimen, mixed in the proportion of 1 measure (at 27° Tw.), to 
 3 measures of a solution of gum substitute at 5 lbs. to a gallon. The mixture 
 is printed on the cloth, which is dried, and the colour is raised (or developed) 
 by passing the fabric through a cold solution of soda-ash at 12° Tw. for two 
 minutes, when it is rinsed in water, washed, dried, and passed through a weak 
 solution of chloride of lime by the mangle, and again dried. 
 
 This colour is also known under the term of "rust" yellow. A darker shade 
 of rust-yellow generally used for warps for goods which are to be coloured 
 Prussian blue, may be coloured in the yarn by the following method : — 
 25 lbs. of clean cotton yarn are run through a bath of 3 lbs. of copperas 
 
 Iron-Bufp. 
 
156 DYEING AND CALICO PRINTING. 
 
 and 2 lbs. of nitrate of iron for about five turns, and are wrung out. The 
 yarn is next taken through a strained cold bath of 4 lbs. of lime for five 
 turns, and the colour is submitted to oxidation in the air. When even, the 
 yarn is again dipped in the iron bath and again in the lime, and oxidised 
 until the desired shade is obtained. The colour is fast. 
 
 Gold leaf, pure or alloyed, or imitation, is applied to woven tissue by means 
 of albumen or a fatty and resinous mordant. 
 
 GREEN MINERAL PIGMENTS. 
 
 Mineral greens may be divided into two groups. To the first belong those 
 mineral compounds possessing a green colour and well-defined chemical 
 constitution, as chrome-green or hydrated oxide of chromium ; Scheele's green 
 or arsenite of copper; Schweinfiirt green or aceto-arsenite of copper; and the 
 emerald greens. The second group includes all those various shades of green 
 which are composed of mixtures of blue and yellow pigments, and constitute 
 simply mechanical mixtures. 
 
 The larger proportion of green pigments belonging to the first group are 
 preparations derived from chromium and copper, to which may be added 
 Rinmann's green, a compound of cobalt and zinc, Rosenstiehl green or 
 manganate of baryta, green ultramarine, and some green prussiates. As 
 Guignet's green, a chrome-green, is extensively used, it may be interesting to 
 know how it is produced. Three parts of boracic acid are intimately mixed 
 with one part of bichromate of potash and a sufficient quantity of water to 
 form a thick paste. The paste is introduced into a furnace and heated to a 
 dull red heat, when a borate of potash and a borate of oxide of chromium are 
 produced. The mass is allowed to cool, and is then thrown into cold water ; 
 the borate of potash is dissolved, and the borate of chromium is decomposed ; 
 the hydrate of the oxide of the metal C2O3 + 3HO subsiding as a magnificent 
 green powder, which only requires to be well washed and drained to be ready 
 for use. This green and that prepared from phosphate of ammonia and 
 bichromate of potash possess the property of maintaining their colour by 
 artificial light. 
 
 Chrome-green, like other pigment colours, is fixed either with ladarine, or 
 with albumen thickened with gum or starch. In either case the cloth is 
 subsequently steamed. 
 
 Among the preparations of copper that possess a green colour only a 
 few are employed in dyeing and printing. The principal are — Arsenite of 
 copper, termed Scheele's green, and designated by as various names as 
 their places of manufacture, is a compound the constitution of which is 
 expressed by the formula As 2 4 Cu"n. This pigment may readily be fixed to 
 tissues by first passing them through a solution of a salt of copper, then 
 through a soda bath to fix the blue hydrate of oxide of copper, and finally 
 through a solution of arsenious acid. A more expeditious method consists in 
 passing the fabric through a bath of arsenite of soda, and then through a 
 solution of a salt of copper, generally the sulphate. The accompanying 
 specimen of printed cloth, from the firm of Messrs. Wood and Wright, 
 coloured with Wilner green, by an arsenical process, illustrates the application 
 of this class of pigment colours. The process is "as follows: — 4 lbs. of sul- 
 phate of copper are dissolved in 1 gallon of hot water, and the solution is 
 
GREEN MINERAL PIGMENTS. 
 
 157 
 
 I Ill II IIMIHBMBI 
 
 Chrome-Green. 
 
 thickened with 1 gallon of gum tragacanth water. The solution when strained 
 and well mixed is ready for printing. When printed, the cloth is passed on 
 rollers through a solution of arsenite of soda at 6° Tw., each length of cloth 
 being about 15 seconds in the bath. The fabric is then rinsed in cold watery 
 dried, and finished. 
 
 The arsenite of soda bath is prepared by dissolving two drams of white 
 arsenious acid in 1 gallon of caustic soda at 5 Tw. If a deeper yellow shade 
 should be desired, more arsenic must be employed ; if a deeper shade of 
 blue, more soda. By varying these constituents several shades of green may 
 be obtained. 
 
 Aceto-arsenite of copper, — 
 
 C 2 H 3 4 , 
 Cu"„ 
 
 Wilner, an Arsenical, Green. 
 

 m 
 
 i 5 8 
 
 DYEING AND CALICO PRINTING. 
 
 is, when used, fixed by means of albumen, but may be fixed chemically by 
 printing on a mixture of acetate of copper and arsenious acid, and steaming; 
 or by rinsing the fabric previously treated with arsenite of copper through a 
 bath of acetic acid. 
 
 The colours derived rom insoluble salts of chromium are numerous, and 
 although with the preseit valuable innovation of aniline dyes it is improbable 
 that chrome or mineral pigments will meet with greatly extended application, 
 we may shortly review ihe characteristics of the principal green pigments. 
 
 Arnaudon green, or netaphosphate of chromium, is a very similar colour to 
 Schweinfurt green, but ess vivid. According to M. Arnaudon it is best pre- 
 pared by mixing equivilent parts of neutral phosphate of ammonia and of 
 bichromate of potassium (128 parts of phosphate and 149 parts of bichromate). 
 The salts are pulvcristd together or dissolved simultaneously in a very little 
 water, and the liquid is evaporated until it can be removed in the mass on 
 cooling. The product is placed in a vessel, and heated upon an oil-bath to 
 180 . Should the temperature rise beyond 200° the green colour will have 
 disappeared. The resilt of this process is washed in water, leaving a fine 
 powder of a colour aprroaching that of budding leaves. The loss of colour 
 at too high a temperatire is probably due to the reduction of the bichromate 
 in excess by the ammojia of the phosphate. 
 
 Plessy green is obtaned, according to the inventor, by dissolving 1 part of 
 bichromate of potassiun in 10 parts of boiling water, and throwing in 3 litres 
 of biphosphate of lime tnd 1/25 kilos, of powdered sugar. A large quantity of 
 gas is quickly disengaged, and when the action is no longer apparent the 
 liquid is decanted, and the precipitate washed in water. 
 
 This green does not suffer alteration by exposure to the action of the air, 
 or of sulphuretted hyd-ogen. For printing this colour is too pale, but it has 
 met with several applications. 
 
 BLUE AND VIOLET PIGMENTS. 
 Blue and violet pignents include ultramarine, the blue colours derived from 
 cyanogen and ferro-c)anogen compounds, cobalt blue, Thenard blue, smalt, 
 phosphate of cobalt, ceruleum, the blue oxides of some of the rarer metals, 
 as for instance, molybcenum blue, tungsten blue, and a few others. 
 
 Ultramarine. 
 The artificial production of this magnificent pigment is one of the greatest 
 conquests of modern chemistry, and is due entirely to the labours of Messrs, 
 Guimet and Gmelin, working, however, independently of each other. The 
 mineral known by sev;ral names, but generally called lapis lazuli, or simply 
 lapis, is one of the lather rare substances found disseminated through a 
 peculiar kind of grani.e, especially in Central Asia. Although it was known 
 in Europe as far back is the times of Raphael and Michel-Angelo (both these 
 artists employed it), hi true composition remained a secret until the begin- 
 ning of this century; but it is from the results of the quantitative analysis 
 of this mineral that be manufacture of artificial ultramarine has taken its 
 origin. The characteristic difference between native and artificial ultramarine 
 is that the native pignent, as obtained by lixiviation of the pulverised mineral, 
 is not acted upon by s rong or distilled vinegar, nor by a concentrated solution 
 
ULTRAMARINE. 
 
 159 
 
 of allum in water, both of which discolour and dcompose artificial ultra- 
 mariine. 
 
 In the year 1814 M. Tassant accidentally observed he formation of a blue- 
 colomred substance in the soda furnace at St. Gobain. The substance having 
 been submitted for analysis to Vauquelin, he found it to be identical in com- 
 position with lapis lazuli, and thence argued the possibility of its synthesis. 
 In tlhe year 1824 the Societe d'Encouragement poir l'lndustrie Nationale 
 offered a prize of 6000 francs (^240) for the discover/ of a practical method 
 for tme preparation of ultramarine by artificial means, it a price not exceeding 
 600 firancs the kilo. In the year 1827 M. Guimet annmnced to the Academie 
 des Sciences that he had succeeded in solving the proilem of the manufacture 
 of thiis substance. The discoverer established a minufactory near Lyons, 
 and lhad for many years the monopoly of the trade, tiough the price of 600 
 francss (£24) per kilo, sank to 30 francs. The then Pnfessor of Chemistry at 
 Tubiingen, M. C. Gmelin, claimed priority of discover/; but after a lengthy, 
 impairtial, and painstaking inquiry, there remained no loubt whatever that M. 
 Guimiet had claim to the premiums offered. 
 
 Thee manufacture of ultramarine is carried on in Fraice and some parts of 
 Gerrmany along the Rhine, and in Bavaria. The pro:ess there in use was, 
 howewer, imported from France. 
 
 Thte trade distinguishes four kinds of ultramarine, vz. — (1). The deep and 
 pure blue, as to its colour quite identical with the average of native ultra- 
 marime. (2). Pale blue ultramarine, sometimes with a;reen tinge, but always 
 a very brilliant pigment. (3). Ultramarines of a violet ir rose hue. (4). Green 
 ultrarmarine, of a dull appearance. As many as thirty-:ix different varieties of 
 ultramarine, gradually verging from perfectly pure blue to pure green, may be 
 met with. 
 
 Ultramarine, artificial as well as native, is decomposid by excess of hydro- 
 chloric acid ; sulphuretted hydrogen is given off, leavng a milky and gelati- 
 nous liiquid, which runs turbid through filtering-paper, oving to the very finely 
 divided state of the sulphur, the quantity of which is far larger in artificial 
 ukraimarine than in the native product. Ultramarine isnot affected by air and 
 sun-ligjht, withstands washing with soap and alkaliis, and is fixed upon 
 tissues; by means of albumen. There exists no procf whatever as to the 
 origin of the blue colour of this pigment. Notwithstmding the number of 
 analysies made of the native as well as of the artificial product, no rationale 
 can be: given of the blue colouration from the compo;ition of the material, 
 while the question arises whether or not the component sibstances are modified 
 as soon as acids are caused to act upon them. 
 
 The manufacture of ultramarine on the large scale rehires a great deal of 
 skilful management, and more than ordinary tact, in reguating the heat, which 
 is always higher than full red-heat. The material callet green ultramarine is 
 the resiult of incomplete ignition. 
 
 Ultraimarine is a substance not subject to wilful adilteration to any great 
 extent; it is sometimes customary to dilute the pigment with whites, such as 
 sulphate of baryta and lime. Ultramarine of good quality exhibits an 
 extremely deep blue powder, which imparts its beautifil colour very readily 
 to otherr substances with which it is mixed. It is used inprinting, and is fixed 
 by means of albumen and steam. 
 
i6o 
 
 DYEING AND CALICO PRINTING. 
 
 We append a sample of cloth dyed with this colour by the firm of Messrs. 
 Walter Crum and Co. 
 
 To fix this colour, the goods, after printing, are steamed for half to one 
 hour. 
 
 The raw materials for the manufacture of artificial ultramarine are — 
 (i). Silicate of alumina, as free as possible from iron, the kaolin of Cornwall 
 being preferred. (2). Calcined sulphate of soda. (3). Calcined soda. 
 (4). Sulphuret of sodium, a by-produft of the manufacture. (5). Sulphur. 
 (6). Pulverised coal or charcoal. The clay is washed with water, dried, 
 ignited, and ground to a very fine powder. The sulphate of soda must be free 
 from lead or iron. Potassium salts will not form ultramarine ; barium salts 
 have the property (see " Chemical News," vol. xxiii., pp. 119, 142, 204). 
 Alkali works supply the calcined soda, which should contain at least 85 per 
 
 Ultramarine. 
 
 cent of carbonate of soda. Caustic soda may be substituted. The sulphur 
 and the carbon are both very finely pulverised. 
 
 There are three methods of preparing ultramarine generally followed : they 
 result in — 
 
 a. Sulphate-ultramarine ; 
 
 (3. Soda-ultramarine ; 
 
 y. Silica-ultramarine. 
 
 a. The preparation of sulphate ultramarine is included in two stages :■— 
 
 1. Preparation of green ultramarine. 
 
 2. Conversion into blue ultramarine. 
 
 (1). The kaolin, sulphate of soda, and charcoal are all finely pulverised ; or 
 if solutions of sulphate of soda, soda, and sulphide of sodium are used instead 
 of powders, the kaolin is stirred with the solution, and the mixture evaporated 
 to dryness and ignited. The materials are employed in such quantity that 
 the soda shall saturate half the silica of the kaolin, and shall be present in 
 
ULTRAMARINE. 161 
 
 sufficient quantity to form with the sulphur polysulphuret of sodium. This 
 and the formation of another sulphuret (Na 2 S) are obtained by observing the 
 following proportions : — 
 
 Dry kaolin ioo ioo 
 
 Calcined Glauber's salt . . . . . . 41 83 — 100 
 
 Calcined soda 41 — 
 
 Charcoal or pit-coal 17 17 
 
 Sulphur 13 — 
 
 This mixture is ignited without access of air, and a white mass is obtained, 
 which becomes green by exposure to air, and blue by being calcined in contact 
 with air. The mixture is placed in fire-clay crucibles, and well rammed down, 
 the crucibles being maintained at a high temperature, with a limited supply of 
 air for eight to ten hours, the ignition being completed at a white heat. The 
 crucibles when cooled are found to contain a semi-fused grey- or yellow-green 
 mass, which is repeatedly lixiviated with water. The green ultramarine con- 
 tains, according to StolzelPs analysis (1855), in 100 parts — 
 
 Alumina 3o - n 
 
 Iron o - 49 
 
 Calcium 0*45 
 
 Sodium x 9*°9 
 
 Silica 37'4-6 
 
 Sulphuric acid 0^76 
 
 Sulphur 6 - o8 
 
 Chlorine 0-37 
 
 Magnesia, potash, phosphoric acid traces 
 
 94-81 
 Oxygen 5-19 
 
 ioo - oo 
 2. The conversion of green into blue ultramarine is effected by roasting 
 t the green ultramarine and sulphur at a low temperature, with access of air. 
 I Sulphurous acid is formed, a portion of the sodium oxidised into soluble sul- 
 f phate being washed out ; the sulphur originally present in the green ultra- 
 r marine remains combined with a smaller quantity of sodium. The roasting 
 i; is generally effected in an iron cylinder, somewhat similar to a gas-retort, 
 3 sulphur being added until the required depth of blue is obtained. The ultra- 
 n marine is then pulverised, lixiviated, dried, and assorted as to quality. 
 
 /8. Soda-ultramarine is prepared from the following proportions of ma- 
 il terials: — 
 
 Kaolin 100 100 
 
 Sulphate of soda — — 
 
 Soda 90 100 
 
 Carbon 6 12 
 
 Sulphur 100 60 
 
 Resin 6 — 
 
 r The ignition is effected in the manner previouslydescribed. By increasing the pro- 
 s' portion of soda and of sulphur, blue ultramarine may be formed at one operation. 
 7. Silica-ultramarine is prepared in a similar manner, silica being added to 
 i. the former materials to the amount of 5 to 10 per cent of the kaolin. Blue 
 
 M 
 
152 
 
 DYEING AND CALICO PRINTING. 
 
 ultramarine is the immediate product of the calcination. The process, how- 
 ever, is difficult to manage, on account of the tendency to fusion amongst the 
 materials employed. 
 
 CYANOGEN COLOURS. 
 The colouring materials of this group are — 
 
 Prussian blue ; 
 
 Soluble Prussian blue; 
 
 Turnbull's blue (two varieties) ; 
 
 Tin blue (two varieties) ; and 
 
 Havraneck's green, or prussiate of chromium. 
 All these preparations are obtained by means of the yellow and red 
 prussiates, or, as they are scientifically called, ferro- and ferri-cyanide of 
 potassium. Prussian blue or Berlin blue was quite accidentally discovered 
 in the year 1710, by Diesbach, at Berlin, whence its name. It was only 
 towards the end of last century that Schecle discovered the relation existing 
 between Berlin blue (ferrocyanide of cyanide of iron) and the yellow prussiate. 
 This salt is technically a very important substance. It contains in 100 parts — 
 Potassium, 37*03 ; cyanogen (carbon, 17*04 ; nitrogen, 19-89) ; iron, 13*25 ; water, 
 12*79. It is considered either as a combination of ferro-cyanogen with potassium 
 and water (Fe3Cy = Cfy)2K + 3HO ; or as a combination of protocyanide of iron 
 (FeC 2 N = FeCy) with cyanide of potassium and water, FeCy+2KCy + 3HO. 
 The salt crystallises in large, deep, iemon-coloured crystals. It loses its water 
 of crystallisation at ioo° ; dissolves in four times its weight of cold, and 
 in a little more than its own weight of boiling water ; insoluble in strong 
 alcohol, which precipitates its aqueous solution. The specific gravity of its 
 concentrated solution at 8° C. is ri3o; the specific gravity of the salt is 
 1*833. Heated to a dull red heat, with exclusion of air, and having been 
 deprived of its water, the salt fuses, is decomposed, gives off nitrogen, and 
 leaves a residue of cyanide of potassium and carbide of iron ; but if 
 any water has been left, and oxygen has access during this ignition, carbonic 
 acid and ammonia are simultaneously given off. A mixture of 8 parts of dried 
 ferrocyanide and 3 parts of carbonate of potash yields, on fusion, cyanide of 
 potassium, carbonic acid and carbonic oxide, and peroxide of iron. The yellow 
 prussiate and its aqueous solution are slowly decomposed by the action of day- 
 light, hydrocyanic acid is given off, and there is formed either Prussian blue 
 or oxide of iron ; the solution assumes an alkaline reaction. The yellow 
 prussiate is manufactured on the large scale : the rationale of the process is 
 that as soon as nitrogenous substances, preferably of animal origin, — horn, 
 blood, refuse wool, leather, and similar materials, — are ignited with potash 
 (carbonate or any other salt of potash decomposable by heat and carbon), and 
 some iron*filings or borings, there are produced, by a complicate reaction, 
 potassium and sulphide of potassium ; the sulphur of the latter is transferred 
 to the iron, and, by the intervention of the potassium and carbon, cyanogen is 
 formed, which in its turn combines with the potassium. It should be borne in 
 mind that cyanide of potassium resists, i. e. is not decomposed by, very intense 
 heat. After cooling there does not exist in the fused mass ferrocyanide ready 
 formed, but only cyanide of potassium and iron, and of course carbonaceous 
 matter; the ferrocyanide of potassium is obtained by lixiviating the fused 
 mass with water. The so-called red prussiate consists, in 100 parts, of 
 
CYANOGEN COLOURS. 
 
 163 
 
 potassium, 35*58; cyanogen (carbon, 2r63; nitrogen, 25 - 54) ; iron, 17*29. 
 This substance is considered to be either a combination of ferricyanogen 
 (2Fc + 6C 2 N=2Cfy) and potassium, 2Cfy,3K, or as a combination of cyanide 
 of iron (2Fe,3C 2 N = Fe 2 Cy 3 ) with cyanide of potassium, Fe 2 Cy 3 +KCy. It is 
 prepared by submitting the yellow piussiate, either in the state of dry powder 
 or in solution in water (the former is preferred), to the a&ion of chlorine gas. 
 As s;oon as the latter ceases to be absorbed the operation is finished. The 
 saline mass is then dissolved in the smallest possible quantity of water, and 
 the red prussiate crystallises out, chloride of potassium being left: — 
 2(2KCy + FeCy) + CI = C1K + (Fe 2 Cy 3 +3KCy). 
 
 Yellow Prussiate. Chlorine. Chloride of 
 Potassium. 
 
 Red Prussiate. 
 
 This salt, which forms beautifully ruby-coloured crystals, its powder being 
 orange-coloured, is soluble in twice its weight of cold, and about its own 
 weight of warm water ; it is insoluble in absolute alcohol, and only very 
 slightly soluble in weaker spirits. The crystals decrepitate on being heated, 
 and yield, on being ignited in closed vessels, cyanogen and a little nitrogen ; 
 while the residue consists of cyanide of potassium, ferrocyanide of potassium, 
 paracyanogen, and carbide of iron. This salt is an energetic oxidising agent, 
 especially in the presence of alkalies ; it converts, for instance, the protoxides 
 of lead and manganese into peroxides; destroys indigo, converting it into 
 isatine, on which account it is sometimes used as a discharge (Mercer's 
 process).* Red prussiate is used by dyers for obtaining peculiar shades of 
 blue. If cotton cloth be passed in the usual way through nitrate of iron, and 
 rinsed, it will make no blue when put into red prussiate ; but if it is afterwards 
 passed into muriate of tin liquor, it strikes a blue direcTly, which has a good 
 shade. Red prussiate is not much used in printing. It is found in some 
 recipes for dark steam blues, and for a few other colours, such as myrtle and 
 chocolates. 
 
 As regards the colours known as Prussian blue we have to distinguish — 
 (r). Neutral Berlin, or Prussian blue, which is obtained when a solution of the 
 ferrocyanide of potassium is poured into any solution of a salt of peroxide of 
 iron, preferably the perchloride ; a very bulky deep blue precipitate is formed, 
 which it is very difficult to free from the ferrocyanide by washing, and tena- 
 ciously retains a portion of that salt. (2). The basic Berlin blue is obtained 
 when a solution of a proto-salt of iron is precipitated by means of a solution 
 of the ferrocyanide ; the precipitate is at first white, but gradually oxidation 
 takes place, which may also be induced by oxidising agents, and the result is 
 the formation of a blue substance, stated to be soluble in water ; this solubility, 
 however, is due to the presence of ferrocyanide of potassium. The Berlin 
 blue of commerce is always a mixture of basic and neutral blue, or, in chemical 
 terms, a ferrocyanide of iron ; but the material as met with in the trade con- 
 tains variable quantities of inert mineral matter, added for the purpose of 
 diluting the colour, or for giving weight, and also as dryers. The substances 
 so employed are chalk, pipe-clay, and the sulphates of lime and baryta. Ac- 
 cording to M. Pohl, there is met with in the trade a kind of Berlin blue that is 
 adulterated with starch coloured blue by means of iodine. 
 
 * Although theoretically an excellent plan, it is not much used in practice, for two reasons, 
 —one of these being its too quick action and the difficulty of properly thickening, and the 
 other its expense. 
 
 M 2 
 
mm VBBHHiHHHHHHHIi^^^HI^HI 
 
 164 
 
 DYEING AND CALICO PRINTING. 
 
 Dark Blue. 
 
 We subjoin specimens of printed cloth, light and dark blue styles, prepared 
 by Messrs. Wood and Wright, Clayton Vale Print Works, Manchester. The 
 dark blue is obtained by printing on the following compound : — 
 4 gallons of water ; 
 
 8 lbs. starch ; 
 
 3 lbs. sal-ammoniac ; 
 
 9 lbs. yellow prussiate of potash ; 
 
 1 lb. red ,, ,, 
 6 lbs. tartaric acid ; 
 
 3 lbs. persulphate potash ; 
 } lb. oxalic acid ; 
 
 2 gallons prussiate tin pulp. 
 
 Light Blue. 
 
CYANOGEN COLOURS. 
 
 165 
 
 The tin pulp is prepared from a mixture of the two following solutions, well 
 stirred, and filtered to a pulp : — 
 
 a. 1 gallon of hot water ; 
 
 1 lb. of yellow prussiate of potash. 
 
 b. 1 gallon of water; 
 
 1 lb. muriate of tin crystals. 
 The cloth when printed is steamed for 40 minutes, aged during one night, and 
 rinsed in a weak solution of bichrome and alum at 120° F. It is then washed, 
 dried, and finished, when it presents the appearance of the specimen. 
 
 The light steam blue is printed from the following standard mixture : — 
 45 lbs. prussiate of potash ; 
 30 lbs. alum ; 
 
 20 gallons of boiling water ; 
 10 gallons of cold water ; 
 3 pints of vitriol. 
 1 quart of this standard is added to 3 quarts of water; there is then added — 
 1 i lbs. of starch ; the bath is boiled, cooled, strained, and then is ready. 
 
 When printed the cloth is steamed for 40 minutes, then aged during one 
 night, and rinsed in a weak solution of bichromate of potash and alum on the 
 mangle. It is then passed through water, dried, and finished. 
 
 A beautiful Berlin or royal blue, almost approaching the aniline blues in 
 lustre, is produced upon wool by the following process : — For 36 lbs. of wool, 
 take yellow prussiate, 4 lbs., and oxalic acid, 6 lbs. Dissolve in water, and 
 enter the wool at ioo° F. ; work well for 2 hours, raising the temperature gra- 
 dually to 180 F. Take out and cool. Cool the liquor with 2 pailfuls of cold 
 water; add 21 lbs. alum ; re-enter the wool, and work for % an hour. Then 
 add I pint of yellow spirit, and work for 1 hour, raising the temperature slowly 
 to 180 F., at which heat work for ij hours longer. Take out and add 1 to 2 
 pints of nitrate of iron, according to shade required. Re-enter the wool, and 
 give five or six turns. Take out, cool, and wash very well. 
 
 The yellow spirit referred to may be made as follows : — Take 18 ozs. tin 
 crystals, 4J lbs. hydrochloric acid, 2 lbs. strongest sulphuric acid, and 2 lbs. 
 water. Dissolve the tin salt in the hydrochloric acid ; mix in a separate vessel 
 the sulphuric acid and water, and when cool mix altogether. Let down with 
 water to 6o° Tw. 
 
 Turnbull's blue is obtained by the action of ferricyanide of potassium (red 
 prussiate) upon solutions of proto-salts of iron. These colours, as such, are 
 not used in printing and dyeing. Alkalies destroy them. They are insoluble 
 in water; and their so-called solution, used as blue ink, is merely the finely- 
 divided solid matter in a state of suspension. These colours are fixed upon 
 textile materials chiefly by two reactions. The goods are mordanted with a 
 solution of iron, — in other words, the hydrated oxide of iron is deposited in 
 the pores of the fibre, — and are then passed through a bath consisting of 
 acidulated prussiate of potash. Or ferro- or ferri-cyanhydric acid, or a mixture 
 of both, is applied to the tissues by passing them through an aqueous solution 
 of the potassium salts mixed with an acid, and the blue colour is brought out 
 by the simultaneous action of steam and the oxygen of the air. The addition 
 of preparations of tin in these processes is not required for developing the 
 colour, but only for modifying its shade. For dyeing wool a so-called royal 
 
- ^^m-^M^^mm^ 
 
 SEEES wbh 
 
 166 
 
 DYEING AND CALICO PRINTING. 
 
 blue, the second method is exclusively employed. It appears that wool ha.s 
 a great affinity for Prussian blue when that compound is set free by heat from 
 a solution of ferro-cyanhydric acid. The wool is therefore placed in a bath of 
 a solution of prussiate mixed with a suitable quantity of royal blue spirits — a 
 mixture of sulphuric, hydrjchloric, and nitric acids. If the red prussiate be 
 used the nitric acid is omitted as needless. The so-called prussiate of tin, or 
 tin-pulp, is chiefly used as an ingredient in printing steam-blues on cotton. 
 It is formed by mixing protochloride of tin and yellow prussiate. The latter 
 should be separately dissolved in one half the water, the tin salt mixed with 
 the other half, when both are poured together and allowed to settle. The 
 following formulae for preparing tin-pulp for steam-blues are in actual use, and 
 will give an insight into its composition: — 
 
 No. 2. 
 
 No. 3. 
 
 8 lbs. 
 
 g lbs. 
 
 5 qts. 
 
 6 qts. 
 
 io gals. 
 
 io gals. 
 
 4 gals. 
 
 6 gals. 
 
 Ordinary White Tin-Pulp. 
 
 No. i. 
 Yellow prussiate of potash* . . . . . . 4 lbs. 
 
 Muriate (protochloride) of tin at 120° Baume 2 qts. 
 
 Water 6 gals. 
 
 Yield of pulp 2 gals. 
 
 The prussiate is first dissolved in one half of the water, the muriate of tin 
 then mixed with the remainder of the water; the two solutions are then mixed 
 together and well stirred, to break up the precipitate into a fine pulp, they 
 are thrown upon a filter, or washed by decantation, and then drained down to 
 the given bulk. 
 
 Blue Tin-Pulp. 
 
 Nine lbs. of prussiate cf potash, 5 gallons hot water, 3 quarts of solution of 
 bichloride of tin at 100° B., 5 gallons of cold water. The two solutions are 
 mixed, well stirred up with about 12 gallons of water, and then drained down 
 to 6 gallons. In mixing dark steam-blues it frequently happens that large 
 quantities of hydrocyanic acid are developed from the hot colours, and some- 
 times men working over the pans or mugs are stupefied or sickened by the 
 smell. There should therefore always be good and efficient ventilation ; but 
 in any serious case the sprinkling of liquid ammonia, and the inspiring of 
 ammonia and alcohol mixed, as well as the immediate removal of the men 
 affected into the open air, should be resorted to. 
 
 Among the methods in use for the production of Prussian blue by printing is 
 the following: — The tissue is first passed through a bath of stannate of soda, 
 next into a bath of very dilute sulphuric acid rinsed well in water and dried, 
 and there is then printed on it a mixture of yellow and red prussiate of potash, 
 prussiate of tin, tartaric and oxalic acids, and sal-ammoniac. The tissue is 
 steamed and afterwards washed. Silk is dyed with Prussian blue by mor- 
 danting with a warm mixture of nitrosulphate of iron and bitartrate of potash, 
 or, instead of the latter, protochloride of tin. The tissue or yarn is rinsed in 
 water, and dyed by means of being passed through a solution of yellow 
 prussiate slightly acidified with hydrochloric or sulphuric acid. Cotton is dyed 
 blue also by this last method. 
 
 * We retain here the names by which in actual practice these chemicals are known, 
 although these names are not the most scientific. 
 
COBALT BLUES. 
 
 167 
 
 French blue is obtained by the following process : — The tissue is treated 
 twice with a solution of stannate of soda at 3 B. ; then passed twice through 
 a bath, composed of 12 parts of a solution of nitrate of peroxide of iron at 
 455° B., 1 part of tin-salt (crystallised protochloride), and i£ parts of sulphuric 
 ac:id. After rinsing through water the tissue is immersed in a bath, composed 
 of 2 parts of yellow prussiate and 1 part of sulphuric acid and sufficient 
 wrater. 
 
 Havraneck green is composed as follows : — 1 part of red prussiate, 4 parts 
 of yellow prussiate, 2 parts of chrome alum, g parts of prussiate of tin in pulp, 
 1 jpart of tartaric acid, 24 parts of water thickened with starch. The colour 
 is developed by steaming. 
 
 Cobalt Blues. 
 
 The substance known as caruleum is a stannate of cobalt mixed with some 
 suilphate of lime, the latter being unessential. The formula of this compound 
 is 3(Sn0 2 ,CoO) + Sn0 2 . The pigment is not affedted by atmospheric influence, 
 lig^ht, or heat; it is neither affected by caustic alkalies or acetic acid, but 
 is dissolved by mineral acids. It is blue also in artificial light. A factitious 
 cai3iuleum is obtained by mixing ultramarine with Naples yellow and white- 
 le^ad. Neither this caeruleum nor smalt (a cobalto-silicate), now only used for 
 poircelain staining, nor Thenard blue (oxide of cobalt and alumina, or phos- 
 phiate of alumina with oxide of cobalt), a very beautiful blue, are now used as 
 pigment colours for calico-printing. 
 
 None of the blue-coloured compounds of molybdenum and tungsten are at 
 prcesent used, either as dyes or as pigment colours, but the introduction of 
 thtese colours may be expected within a few years. 
 
(i68) 
 
 CHAPTER III. 
 
 COLOURING MATTERS OF ORGANIC ORIGIN ARTIFICIALLY OBTAINED. 
 
 ' I A HE discoveries of scientific chemists made during the last thirty years 
 have brought about the use, on a large scale, of substances suitable for 
 dyes obtained by purely chemical reactions ; in practice on the large scale 
 there have been, however, a few instances of a somewhat similar nature, 
 in so far as regards the obtaining of dyes and pigments from perfectly colourless 
 materials. We may mention, as an example, the conversion of lichens under the 
 joint action of air and putrid urine into a beautiful reddish violet matter long 
 before scientific chemists proved that the colourable acids of these plants are 
 changed first into orcine and then into coloured orceine under the influence 
 of oxygen and ammonia. Among the colouring matters of organic origin 
 artificially obtained, we distinguish the following groups: — (i). Colours derived 
 from uric acid ; (2). Colours derived from aniline and the oily non-oxygenated 
 alkalies homologous, isologous, and analogous to aniline ; (3). Colours obtained 
 from phenol and substances analogous therewith; (4). Naphthaline colours; 
 (5). Colours derived from vegetable alkaloids ; (6). Some colouring matters of 
 various origin. All these substances agree in this point, that carbon is an 
 essential element of their constitution. Some of them contain beside, 
 hydrogen and oxygen; others, again, nitrogen, in addition to the hydrogen, 
 while the oxygen may or may not be present. As a consequence of their 
 constitution these substances are unstable under the influence of high tem- 
 peratures, and combustible, i.e., converted into water, carbonic acid, and 
 nitrogen at a red heat with access of air ; some of these substances are weak 
 acids, others, again, strong alkalies comparable with ammonia, and not a few 
 are quite neutral. 
 
 Colours Derived from Uric Acid — Purpurates, Murexide. 
 Purpuric acid, the ammoniacal salt of which is termed murexide, is one of 
 the most interesting groups of a series of products of decomposition.* 
 Murexide was discovered by Scheele in the year 1776, as a product of the 
 splitting up of uric acid, Ci H 4 N 4 06, a substance which has not been 
 hitherto artificially prepared. This material, when acted upon by nitric acid 
 or other oxidising agents, is converted into urea, C 2 H 4 N 2 2 , a neutral sub- 
 stance, and into alloxan — 
 
 (C I0 H 4 N 4 O 6 ) + (N0 5 .HO) . C 2 H 4 N 2 2 + C 8 H 4 N 2 IO + N0 3 . 
 Uric acid. Urea. Alloxan. 
 
 * It is better to apply here the term splitting up (Spaltung), as the Germans call it. 
 
COLOURS FROM URIC ACID. 
 
 169 
 
 Since nitrous acid is simultaneously set free, the urea is immediately destroyed 
 and converted into carbonic acid, water, and nitrogen — 
 
 C 2 H 4 N 2 2 + 2N0 3 = 2C0 2 +4H0+4N, 
 
 Urea, 
 so that the result of the reaction of nitric acid is the formation of alloxan, a 
 substance capable of crystallisation, soluble in water, of an unpleasant odour, 
 and staining the skin red. Alloxan is one of those substances the molecules of 
 which are en mouvement perpetuel, and, hence, prone to ready conversion into 
 another substr.uce called alloxantin, containing 1 atom less of oxygen — 
 C 8 H 4 N 2 IO ; C 8 H 2 N 2 7 +3HO, 
 
 Alloxan. Alloxantin. 
 
 This conversion of the former into the latter substance is effected by the action 
 of reducing agents ; for instance, nascent hydrogen, and also when alloxan is 
 simply boiled with water. In the latter case parabanic acid is also formed, 
 and carbonic acid given off; when a small quantity of an acid is added to the 
 water wherein the alloxan is boiled alloxantin is also generated, but urea, 
 oxalic, and carbonic acids are simultaneously formed. Alloxantin, accompanied 
 by some alloxan, is directly* formed when uric acid is treated with dilute 
 nitric acid ; from alloxantin, when treated with chloride of ammonium, is 
 formed dialuramide, and from that substance murexide, or purpurate of 
 ammonium (NH 4 0,C 1 6H 4 N 5 On + 2HO) is generated under the following 
 circumstances: — (a) By the oxidation of dialuramide by means of the oxides 
 of mercury or silver ; (b) By the action of ammonia upon alloxantin ; 
 (c) By the action of ammonia or of carbonate of ammonia upon alloxan, or 
 better, a mixture of alloxan and alloxantin ; (d) By destructive distillation of 
 alloxan by itself, or of that substance mixed with an organic body. For the 
 manufacture of murexide on the large scale guano is chiefly employed as the 
 source of uric acid, and the process adopted may be described in the following 
 terms : — Peruvian guano* of best quality is placed in a suitable leaden vessel, 
 and mixed with hydrochloric acid at 18 Tw., boiled therewith for one hour, 
 while the mixture is kept well stirred up. The mass is next filtered through 
 coarse linen and washed with water; the acid removes from the guano a 
 quantity of inert salts, decomposing the combination of the uric acid and 
 ammonia, setting the former free, since that substance in its free state is very 
 sparingly soluble in water, and especially so when it contains an acid. The 
 uric acid remains on the filter among the sand and other nondescript 
 substances insoluble in hydrochloric acid of the above strength ; the pasty 
 mass left upon the filter is placed in a large porcelain dish, and mixed with its 
 own weight of HC1 at 40 Tw., and heated to 40 ; when the action of the acid 
 has been continued for a short time there is added to the mass the T 'jth part 
 of the weight of the substance as when taken from the filter, of nitric acid, 
 and the temperature kept steadily between 44 and 62 . This proceeding has 
 the effect of converting the uric acid contained in the guano into alloxantine 
 and alloxan ; after a while an equal bulk of water is added to the fluid in the 
 basin, and the whole left quietly standing to deposit insoluble matters, the 
 
 * This guano contains a pretty large quantity of urate of ammonia, in addition to a host of 
 other substances. 
 

 170 
 
 DYEING AND CALICO PRINTING. 
 
 clear liquid is decanted, and the insoluble residue frequently washed with 
 water ; the clear solution thus obtained contains as its main constituent 
 alloxan and alloxantin ; the former of these substances is entirely converted 
 into alloxantin by means of the reducing action of protochloride of tin, and 
 precipitated in the shape of alloxantin ; this precipitate having settled down 
 the clear supernatant liquid is withdrawn, and the pasty mass thrown on a 
 linen filter and washed with acidulated water. After having been carefully 
 dried and reduced to powder, it is placed in a porcelain basin, set in another 
 basin containing liquid ammonia, and put aside in a warm place until the 
 powder has been entirely converted into a brilliant purple mass. In other 
 words, it has been converted into murexide ; since alloxantin forms, when it 
 is in an atmosphere containing ammonia and water, murexide (purpurate of 
 ammonia*). 
 
 Pure murexide when dry is a brilliant crystalline powder of metallic lustre and 
 a golden greenish hue akin to that of the wings of Spanish flies. Placed between 
 the eye and the light these crystals appear red, and when pulverised the 
 powder is red. At ioo° the crystals lose 1 molecule of water. Murexide is 
 insoluble in alcohol and ether; sparingly soluble in cold water, to which it 
 imparts a reddish hue ; in hot water the solubility is greater. Murexide is 
 far more soluble in solution of nitrate of lead, wherewith it does not undergo 
 double decomposition. The purpurates of baryta, silver, mercury, and lead 
 (if acetate be used) are insoluble in water. Murexide dissolves in an aqueous 
 solution of caustic potassa, yielding a most magnificently blue solution, 
 which becomes colourless on the application of heat. Murexide is now no 
 longer used for dyeing or calico printing, having been superseded by the 
 aniline colours. It was met with in trade in three different conditions, 
 viz., as paste, as powder, and in crystals. The manufacture of this article 
 required great skill and nicety of management, and, consequently, the sub- 
 stance was always expensive. Murexide was applied as a dye to silk and 
 wool by mixing with corrosive sublimate, acetate of soda, and acetic acid. 
 For printing, a mixture of murexide with nitrate of lead or acetate of zinc 
 properly thickened is applied on cotton fabrics, which are then allowed to dry 
 for a day or two, when the colour is fixed by passing them through a mixture 
 of corrosive sublimate, acetate of soda, and acetic acid. A modification of 
 this process was used very successfully some years ago by mixing a thickened 
 solution of murexide in nitrate of lead, with a thickened solution of bichloride 
 of mercury (these solutions do not precipitate each other for some twenty- 
 four hours, and then only imperfe<5Uy)- This colour was then printed on the 
 cloth and aged two or three days, and fixed by simply running through a 
 solution of acetate of soda. This allowed murexide colours to be printed along 
 with, and after, other colours which would have been spoiled by running 
 through a solution of bichloride or pernitrate of mercury, which latter salt 
 was chiefly employed. Murexide on woven tissues can be detected — 
 
 1. By its beautiful and brilliant rose or purplish rose amaranth, which 
 behaves with reagents in the following manner: — (a). The colour is destroyed 
 by dilute mineral acids (hydrochloric, nitric, and sulphuric); (b). Caustic 
 alkalies also destroy the colour, which, however, turns first blue ; washing 
 
 Purpuric acid is not known in isolated state. 
 
COLOURS FROM ANILINE. 
 
 171 
 
 with soap gradually destroys the colour; (c). Reducing agents, as sulphurous 
 acid, protochloride of tin, hydrosulphuret of ammonium, and protosulphate 
 of iron, also rapidly destroy this colour. 
 
 Purple of the Ancients. 
 
 The use of a purple colour extracted from certain univalve molluscs dates 
 back to a very remote period of antiquity. The tissues, chiefly linen and 
 wool thus dyed, were always held in high esteem, and were extremely 
 costly. The real art of applying this dye, and the precise kind of mollusc, 
 are to a great extent matters of conjecture. Dr. Sacc has published a 
 lengthy, yet very interesting, paper on this subject.* It is a positive fad 
 that in different parts of the seas of our globe in hot, temperate, and even 
 cold climates molluscs are found which contain in a peculiar organ a very 
 thick yellowish green liquid, which gradually imparts to tissues a purplish 
 colour. A Mr. William Cole, of Bristol, obtained a high reputation by the 
 fact that he discovered, in the year 1663, the mollusc which had been for some 
 time used by a dyer of that city to impart to tissues a brilliant and fast purple 
 colour. Messrs. B. de Jussieu, Reaumur, Duhamel, and Bancroft experimented 
 in the course of the last and beginning of this century with various molluscs 
 for the purpose of dyeing tissues. 
 
 M. Gonfreville records that in some parts of India a mollusc, known as a 
 murex, is kept alive in sea-water until a sufficient number is obtained; 
 from 4000 to 5000 of these shell fish are required to dye 1 kilo, of wool, for 
 which purpose the shells and contents are broken up while placed in sea- 
 water, and left standing for several days afterwards in leaden vessels. The 
 wool to be dyed is immersed in the liquid, or sometimes the liquid is applied 
 to the tissue by means of a brush. According to M. de Saulcy, the ancients 
 derived their purple from the Purpura hemastoiua, known to Pliny as Buccinum, 
 and also from the Murex brandaris, which Pliny called Purpura. At Athens 
 and Pompeii large quantities of these shells have been discovered lying in 
 heaps close to ancient dye-works. The ancients distinguished Tyrian and 
 Byzantium purple; the former had the colour of coagulated blood ; the latter 
 exhibited a more violet hue. Both were in every respect fast colours. 
 
 Colours Derived from Aniline and Kindred Bodies. 
 Aniline was first discovered in 1826 by Unverdorben among the products of 
 the destructive distillation of indigo. Runge extracted from coal-tar a sub- 
 stance which he named Kyanol, which, when treated with hypochlorite of 
 lime, yielded a brilliant blue colour, and which was afterwards proved to be 
 identical with aniline. Up to 1856 this substance remained a mere laboratory 
 curiosity, devoid of industrial application. To Runge the honour is, therefore, 
 due of having first drawn attention to the possibility of obtaining aniline from 
 coal-tar, and of applying it to the production of tinctorial substances. 
 Fritzsche found that aniline yields with aqueous solution of chromic acid a 
 bluish-black precipitate. In 1853, Beissenhirtz described the blue colour 
 resulting from a mixture of aniline, bichromate of potassa, and sulphuric acid. 
 Stenhouse, when experimenting on furfurol, found that aniline and its acetate 
 
 * Bulletin de la Societe de Mulhouse, vol. xxvi., p. 305. 
 
l^m^asSss^S^msS^^^S^&^m^W^J^^ii 
 
 
 172 
 
 DYEING AND CALICO PRINTING. 
 
 yield with the former substance a magnificent carmine-red colour. Natanson, 
 in 1856, showed that when aniline and chloride of ethyl (Dutch liquid) are heated 
 together in sealed tubes to 200°, the mixture assumes a beautiful blood-red 
 colour. Professor Hofmann discovered a product resulting from the action of 
 tetrachloride of carbon upon aniline, which yields a brilliant carmine colour 
 soluble in alcohol. It is, however, quite impossible to give, in our allotted 
 space, a historical review of the numerous discoveries made in this immense 
 field. The most distinguished investigators in this department are Messrs. 
 Perkin, Verguins, Mansfield, Collas, Zinin, Gerber-Keller, Heilmann, Medlock, 
 Nicholson, Girard and De Laire, Hofmann, Lightfoot, &c. 
 
 We will now proceed to examine, first, the primitive material aniline, and 
 the sources whence it is obtained, and, secondly, the coloured derivatives 
 which it is capable of yielding. 
 
 Aniline (kyanol, of Runge ; crystalline, of Unverdorben; nitride of phenyl 
 and hydrogen ; phenylamine ; benzidam) has the composition C 12 H 7 N. It 
 contains, in 100 parts — C, 77*41 ; H, 7*54; N, i5 - o5. When pure it is a 
 colourless, highly-refractive liquid, of the sp. gr. 1-028 at 15 C. Its vapour- 
 density is 3"22o. It boils at 182 C, and does not congeal at — 20 C. It is 
 volatile at the ordinary temperature of the atmosphere. It has a faintly aromatic 
 unpleasant odour, and an acrid, burning taste. It is slightly soluble in water, 
 from which it may precipitated by common salt. With alcohol, ether, aldehyd, 
 and the fixed and volatile oils it can be mixed in every proportion. 
 
 Aniline combines directly with the hydracids and the hydrated oxacids, forming 
 salts similar to those of ammonia. These compounds are nearly all soluble 
 in water and alcohol, and are capable of assuming the crystalline form. The 
 alkalies and alkaline earths displace aniline from its combinations with acids, 
 but aniline decomposes the salts of iron, zinc, and aluminium, precipitating 
 the hydrated oxides of those metals. In contact with air aniline rapidly 
 alters its colour, becoming brown, and is finally converted into a resinous 
 mass. Its salts, when pure, are colourless, but in contact with the air they 
 gradually assume a reddish colour. Solutions of the aniline salts colour fir- 
 wood and elder-pith a deep yellow, which is not discharged by chlorine. 
 This colour is apparent when only 1-500, oooths of aniline is present. 
 
 Aniline and its salts may be detected by the following reactions : — When a 
 small quantity of any aniline salt is placed upon a plate of white porcelain, and 
 mixed with a few drops of concentrated sulphuric acid, and a few drops of a 
 solution of chromate of potassa are next added, a beautiful blue colour is formed, 
 which very soon disappears. A solution of an alkaline hypochlorite, when 
 mixed with aniline or any of its sails, gives rise to a violet-blue colour, also 
 fugitive. If a single drop of a solution of 1 part aniline in 1000 parts dilute 
 sulphuric acid (1 part monohydrated acid in 7 of water) is placed on a piece 
 of platinum-foil, and brought into contact with the positive pole of a single 
 Bunsen galvanic cell, an intense blue colouration is instantly produced, 
 which passes successively to violet and rose-red when the drop is touched with 
 the negative pole. 
 
 Perfectly pure aniline may be obtained by distilling indigo and isatine with 
 the hydrates of potash and soda. Anthranilic acid, a product of a hot, con- 
 centrated solution of potassa upon indigo, is decomposed into aniline and 
 carbonic acid by distillation with caustic lime. It is scarcely needful to 
 
COLOURS FROM ANILINE. 
 
 173 
 
 remark that the aniline of commerce is not prepared in this manner. Its 
 source is coal-tar, which contains, according to the most recent investigations, 
 upwards of fifty distinct bodies. These are classified in three groups, according 
 as they are acid, neutral, or basic. Others divide them into hydrocarbons, 
 consisting of hydrogen and carbon only ; oxygenated or sulphuretted com- 
 pounds free from nitrogen ; and, lastly, nitrogenised compounds, analogous to 
 ammonia. Amongst these aniline also occurs, but in so small a proportion, 
 scarcely amounting to 0-5 per cent, that it is of no practical value. It may, 
 if desired, be extracted by treating the products coming over between 150 and 
 200 C. with dilute sulphuric acid, and subsequent decomposition of the sulphate 
 of aniline thus obtained with hydrate of soda or milk of lime. Hofmann's 
 process, described in the Annalen dcr Chemie und Pharmacie, vol. xlvii., p. 30, 
 maybe also applied. Aniline is therefore manufactured in an indirect manner 
 from benzine or benzol, — another of the coal-tar products, which thus 
 becomes the starting-point of the aniline colours. 
 
 Benzol was discovered by Faraday, early in the present century, among 
 the products of the oil gas manufacture. It is obtained pure by distilling 
 benzoic acid with three times its weight of hydrate of lime. By this process 
 benzol is obtained as a colourless, highly mobile fluid, of sp. gr. o - 85, and 
 boiling at 85 C. When cooled down to o° C, it forms a crystalline mass, 
 which liquefies at 7 C. Benzol is insoluble in water, but dissolves readily 
 in alcohol and ether. It is a true hydrocarbon, consisting only of carbon 
 and hydrogen. Its formula is Ci 2 H6. This substance is present in the state 
 of vapour in common coal-gas, from which it may be extracted by treating 
 the gas at a low temperature with alcohol, or, better, petroleum oil, from 
 which solvents the benzol is separated by rectification at a very gentle heat. 
 As yet benzol is chiefly, if not solely, obtained from coal-tar. This liquid 
 is distilled in suitable apparatus.* The benzols (mixtures of hydrocarbons 
 homologous with true benzol), which pass over between 8o° and ioo° C. are 
 called light benzols. Those collected from ioo° C. to 130 9 C. are known as 
 heavy benzols. The products thus obtained are converted separately into 
 nitro-benzols. The benzols of commerce consist chiefly of the hydro- 
 carbons, benzol, and toluol, cymol and cumol being present in small quantities 
 only. 
 
 To give an idea of the contents of several species of coal-tar, we add here 
 the results of investigations made on this subject by Dr. Grace Calvert. 
 
 m. > u c .c i- 
 
 2 3 2 £ ^ 2 - 
 
 a J3 "^ >< 3 « 1- 
 
 no, ffi 0- z Q 
 
 The tar of Boghead coal contains ..12 3 30 41 o 14 p.c. 
 
 „ Cannel 9 14 4° ° *5 22 ■■ 
 
 „ Newcastle 2 5 12 o 58 23 ,, 
 
 ,, Staffordshire 5 9 35 ° 22 2 9 » 
 
 The benzol is treated with a mixture of strong nitric and sulphuric acids, 
 and is thus converted into nitro-benzol, Ci 2 H 5 N0 4 . This latter substance 
 is converted into aniline by means of a process invented by Bechamps. 100 
 
 * See Reimann's Handbook of Aniline, p. 3. 
 

 
 MMMMMWMILM 
 
 174 
 
 DYEING AND CALICO PRINTING. 
 
 e a 
 
 55 £ 
 
 2 fr 
 
 Q K « 
 
 Ot) . 
 
 o o iu 4> i> u ' ■ o -' 
 K PS X K «Ph pi « 
 
 Colour obtained as com- 
 pared with "^ £ 
 crystal magenta = iooo. 
 
 N P) N w 1-1 
 
 Sp. 
 
 gr. of the anilines at o cri 00 
 16- C. 2 S n 
 
 in en m 01 cti 
 
 Oi ui n lO 
 
 Boiling-points of 
 anilines. 
 
 00 00 01 o 01 O 
 
 the 
 
 M N <N N N N 
 
 u"> lO O 
 
 Amount of aniline yielded 
 
 by 100 parts a in vo JT> <o 
 
 of the nitro-benzin. 
 
 m r-» r^ in 10 ,r > CTi >n r~- N 
 Sp.gr. of the nitro benzols £ « k^S-^^NM" 
 
 at l6° C. MH.MMMMMMMM 
 
 Boiling-points of the nitro- ^ ^ 
 benzols. 
 
 10 o 10 
 
 n n m «■> 
 
 MMNNNNCOfO 
 
 00 oo 
 
 Sp. gr. of the benzols at m ^ 
 15" C. c* en 
 
 0101O1010101010 
 
 ■*■ in O 
 
 Benzols classed by their °? °° ?* , VTTTVTT 
 
 boiling-points. () l I I I I J 
 
 fo o ino»nOinOinOin 
 
 CO 00 00 CHOlOOWwNN 
 
 S^ fcfl -=: •» 
 
COLOURS FROM ANILINE. i 75 
 
 parts of nitro-benzol are mixed with an equal quantity of acetic acid and 
 200 parts of iron filings, when the following reaction ensues: — 
 
 8Fe + C I2 H 5 N0 4 +8HO + i2C 4 H303 = 4(Fe 2 03.3C 4 H 3 3 ) + C ia H 7 N + 6H. 
 The mixture, after the addition of a quantity of lime sufficient to decompose 
 any acetate of aniline which may have been formed, receives a current of 
 steam, preferably superheated, which carries over the aniline, partly dissolved 
 and partly in a state of mechanical suspension, into a condenser. When cold 
 the. aniline settles out of the water and is readily collected. 
 
 The products met with in the market under the name of aniline vary ex- 
 ceedingly. It may, indeed, almost be said that we meet with as many 
 qualities as makers. The boiling-points vary from 180° or i82°to 195° C, and 
 again from 200 to 210 C. The chemical characters vary according to the 
 nature of the benzol employed. The following table illustrates these 
 variations. Eleven kinds of benzol were taken, and their boiling-points and 
 specific gravities having been noted, they were converted into nitro-benzols. 
 Here, again, the boiling-points and specific gravities were observed, and they 
 were transformed into anilines. The amount obtained, the specific gravity, 
 and boiling-point of each was registered, and the anilines having been finally 
 converted into magentas, the yield and quality was tabulated in each case. 
 
 Table B shows the nature and composition of some mixtures made with 
 the above anilines, as well as the yield of these mixtures in colouring matter. 
 These mixtures consist of equal parts of two or more of the anilines shown 
 in Table A. 
 
 TABLE B. 
 
 Boiling-points R f e ' at , ive A ™? nt * 
 Mixtures of the of the of Colour obtained 
 
 Different Anilines. corresponding compared with Shades on Stuffs. 
 
 Hydrocarbons. SfflV,™ 
 
 Kosamline. 
 
 b + c 8o°— qo° 16 I Very violet red Rosaniline 
 
 I and mauvaniline. 
 
 d+e go — ioo° 17 Red. 
 
 f+g ioo°— no c 32 Red. 
 
 h+i no»-i2o» 24 f Reddish-yellow Rosaniline 
 
 T ( and chrysotoluidine. 
 
 j + k 120 — 130* 18 Red. 
 
 b + c-\-d + e . . .. 8o° — ioo° 24 Red violet. 
 
 d + e + f+g.. . . 90°— 110° 37 Red. 
 
 f+g+h + i.. . . 100° — 120° 31 Red. 
 
 h + i+j + k . . .. no° — 130 19 Red. 
 
 b+c+d+e+f+g) 000 o j 
 
 it , •, •; a r 8o° — 130 25 Red. 
 
 To ascertain the commercial value of samples of aniline a careful deter- 
 mination of the boiling-point is always sufficient for the purposes of the 
 manufacturer. The absence of water, benzol, and nitro-benzol, must first be 
 proved. The presence of water and benzol is directly seen, upon submitting 
 a portion to distillation, both by the thermometer and by examination of the 
 first few drops which come over. Nitro-benzol is easily detected by saturating 
 the suspected aniline with pure hydrochloric acid. If free from nitro-benzol 
 the mixture will remain perfectly clear. Even a slight trace of nitro-benzol is 
 sufficient to render the mixture milky. 
 

 176 
 
 DYEING AND CALICO PRINTING. 
 
 Luxer ascertains the value of commercial anilines by estimating the amount 
 of red colour which they respectively yield. Five grammes of the aniline in 
 question and 5 grammes of syrupy arsenic acid, of sp. gr. 2"059, are heated to 
 150 for several hours, in the oil-bath, until the formation of a reddish-brown 
 substance, with a greenish reflection, which on cooling becomes a hard, brittle 
 mass. This is exhausted with boiling water, and made up to the bulk of 
 1 litre : 50 c.c. of this solution are taken and diluted with water to \ litre, and 
 in this fluid 6 grms. of woollen yarn are dyed, and the resulting samples com- 
 pared as to intensity and tone. This test is considered fallacious by many 
 practical men, as with such small quantities the regulation of the temperature 
 is very difficult. Thus a variable quantity of aniline may remain unacted upon. 
 It is necessary that the manufacturer should previously satisfy himself what 
 boiiing-points of aniline, or of a mixture of aniline and toluidine, are best 
 adapted for his purpose. This having been done he will find the boiling-point 
 a valuable guide. 
 
 Reimann, to distinguish the so-called light from the heavy anilines, — or, as 
 he names them, kuphaniline and baraniline, — heats slowly a certain quantity 
 of any sort of aniline oil, and notes the quantity which distils over at various 
 temperatures, degree by degree. More simply, the quantities are noted which 
 distil over during a rise of 5 degrees. The quantities of distilled oil may be 
 measured by receiving them in a graduated cylinder. 
 
 He puts 100 c.c. of kuphaniline in a glass retort, placed in an oil-bath heated 
 by a lamp. The tube of the retort is joined to a Liebig's condenser, at the 
 extremity of which a graduated cylinder is placed to receive and measure what 
 distils over. The condenser is supplied with water in the usual manner ; a 
 thermometer is placed in the neck of the retort, and heat applied. Up to 
 180° C, 8J c.c. passed over; from 180° to 185 , 54 c.c. ; and from 185 to 190 , 
 34 c.c. ; so that, say, 3 J remained in the retort. Other samples of light aniline 
 yield numbers, not indeed identical, but similar. 
 
 Heavy anilines treated in the same manner allow only 3^ c.c. to pass over 
 up to 190° C. From igo c to 195 , 8 c.c. distil over ; up to 200° C, 18 ; to 
 205 C, 39; from 205 to 210°, 19 ; and from 210° to 215 , 7 c.c. ; 5 J remaining 
 in the retort. All the anilines of commerce are mixtures of light and heavy 
 aniline in various proportions, and they distil over at intermediate tempera- 
 tures, according to their composition. By distilling the following mixtures — 
 
 90 per cent kuphaniline with 10 per cent baraniline 
 
 85 „ 15 
 
 80 ,, 20 „ 
 
 75 .- 2 5 
 
 ■ 62i „ 37* 
 
 60 ,, 40 ,, 
 
 50 „ 50 
 
 37i .. 62 * » 
 
 25 .. 75 
 
 — and adding to the result the numbers given above, found by distilling pure 
 kuphaniline and baraniline, he has constructed the following table, where K 
 denotes light and B heavy aniline : — 
 

COLOURS FROM ANILINE. 
 
 177 
 
 Deg. c. 
 180 
 
 185 
 
 100 K 
 oB 
 
 2i 
 6 
 
 54 
 
 go K 
 10 B 
 
 85 K 
 15 B 
 
 2i 
 
 8j K 
 20 B 
 
 50 29I 22 
 
 75 K 
 25 B 
 
 3 4 
 3i 
 51 
 
 60 K 
 40 B 
 
 4 
 3 
 
 2i 
 
 50 K 
 50 B 
 
 4 
 3 
 4i 
 
 374 K 
 62I B 
 
 25 K 
 75 B 
 
 3 
 
 21 
 
 24 
 
 i go 
 
 195° 
 200° 
 205" 
 
 210° 
 215" 
 
 Residue 
 
 34 
 
 34 561 55l 55* 
 
 ■I 1 
 
 37 
 
 71 81 
 
 1 5 
 9 
 44 
 
 25 33 
 
 84 - 
 
 5 16 
 
 44 - 
 
 74 54 44 
 40 17 
 284 36 
 
 42 
 19 
 
 34 
 
 34 34 
 
 64 
 
 34 
 61 
 
 7'. 
 31 
 
 16 
 
 8 
 
 44 
 
 5 
 
 100 K 
 zoo B 
 
 2 
 14 
 
 39 
 J 9 
 
 7 
 54 
 
 All that is required is to distil over a sample in the manner described above, 
 note the quantities coming over at different temperatures, and compare the 
 figures thus obtained with the table. In this manner the composition of a 
 sample may be ascertained accurately enough for all practical purposes. 
 
 The aniline of commerce is a mixture of pure aniline and toluidiue in 
 variable proportions, the former preponderating in the light, and the latter in 
 the heavy samples. Odorine and other substances are also present in small 
 amount. Its colour is darker than that of pure aniline, and its smell more 
 offensive. 
 
 Toluidine, C 7 H 9 N, was discovered by Muspratt and Hofmann (" Annalen 
 der Chemie unci Pharmacie," vol. liv., p. 1). It is a solid, crystalline body, 
 which liquefies at 40° C. and boils at 198 C. It has an odour like that of 
 aniline, and a burning taste. It is soluble in wood-spirit, alcohol, ether, 
 aceton, and in the volatile and fatty oils. It forms with the acids a series of 
 crystalline salts, most of which are soluble in water. Its acid solutions stain 
 fir wood and elder pith a deep yellow, just like aniline. With hypochlorite 
 of soda it yields, not a violet, but a reddish tinge. With nitric acid it becomes 
 a deep red, whilst aniline gives an indigo-colour, and with chromic acid it 
 furnishes a brown precipitate. The toluidine of commerce is obtained from 
 nitro-toluol, in the same manner as aniline is obtained from nitro-benzol. 
 
 The methodical classification of the coloured reactions of aniline is not free 
 from difficulty, as some of the results have not been scientifically investigated. 
 The fact is that many manufacturers used in their experiments commercial 
 anilines of unknown composition, and did not care to examine either the exact 
 nature or origin of the tinctorial substances obtained. Under the common 
 name of " aniline colours " we find included bodies which result from the 
 simultaneous action of other bases. It should further be observed, that one 
 and the same chemical reagent is capable of giving rise to several coloured 
 derivatives, according to the time of action, temperature, degree of concen- 
 tration, &c. Still we generally find a primary result of the reaction, the others 
 being merely by-products, or, indeed, impurities which it is difficult to remove. 
 We shall give such facts only as are of practical value, or which serve to 
 elucidate the history of the aniline manufacture. The following colours are 
 derived from aniline : — 
 
1 - ■$$$ 99 HWBff 
 
 i 7 s 
 
 DYEING AND CALICO PRINTING. 
 
 ANILINE REDS. 
 
 Magenta, Fuchsine, Azaleine, Roseine, Rosanilinc, Aniline Crimson, Rubine, 
 and a variety of other trade names. 
 
 Aniline red, though not historically the first of its class, is scientifically and 
 commercially the most important. In addition to its direct applications in 
 dyeing and printing, it serves as the raw material for the manufacture of most 
 other aniline colours. The production of this colour was first observed in 
 1856, by Natanson. Subsequently it was obtained by Hofmann, as a result of 
 the reaction of tetrachloride of carbon upon aniline, and by Verguin, who 
 substituted the anhydrous bichloride of tin for the carbon compound. 
 
 Hofmann's process is still in practical operation on the large scale at the 
 establishment of Gerber-Keiler, at Mulhouse. Three parts of aniline are 
 treated together with one of chloride of carbon to the temperature of 170 to 
 180° C. (347 F.), of course under pressure. After several hours a brown- 
 red mass is formed, which is treated with water, the extract evaporated to 
 dryness, and the residue again extracted with alcohol, to take up the colour. 
 (•' Comptes Rendus de l'Academie des Sciences," vol. lxvii., p. 492). The red 
 colour thus obtained is said by some to be quite distinct from common 
 magenta, and is known in commerce as Hofmann's red. Reimann, however, 
 is of opinion that the difference between this colour and magenta depends 
 merely upon an unimportant admixture. 
 
 Renard Bros, and Verguin, of Lyons, patented the following process in 1859. 
 They make use of small melting-pots of enamelled cast-iron, containing about 
 20 kilos. Into each of these they introduce 10 kilos, of aniline, and afterwards 
 add by degrees 7 kilos, of anhydrous bichloride of tin, constantly stirring. 
 The mixture is made under a hood communicating with a chimney, in order 
 that the dense irritating vapours disengaged may be carried off as they are 
 produced. As soon as the ingredients are incorporated, the pots are exposed 
 to a naked fire in a small furnace, and raised to the boiling-point for 20 or 30 
 minutes. The mass remains fluid, and passes gradually from yellow to red, 
 growing darker till it appears black. The product is tried from time to time, 
 and as soon as it appears of an intense, bright, pure red, when spread in a thin 
 layer upon a piece of white porcelain, the operation is stopped. The hot 
 liquid matter is poured into stoneware jugs, and sold in this state without any 
 purification. 
 
 This process of Gerber-Keiler, Durand, and Schlumberger consists in 
 heating in an oil-bath, in a suitable apparatus, up to the boiling-point, 10 parts 
 of aniline with 7 to 8 parts of nitrate of mercury, very dry and finely powdered. 
 By degrees the mass becomes brown, and is transformed into a fine red 
 liquid. The operation is then concluded, and the liquid is withdrawn from 
 the fire, when it begins to thicken, puff up, and give off yellow vapours. It is 
 then poured, in a thin stream, into two or three times its weight of boiling 
 water, with constant stirring. The unconverted aniline floats on the surface, 
 and the residue is taken up and treated again with boiling water as long as 
 anything is dissolved. These liquids are precipitated with common salt, and 
 the deposit collected on a filter. The following conditions must be observed: 
 — The operation lasts 8 to g hours, and the nitrate of mercury is added in 
 very small portions at once, with constant stirring. The colour prepared in 
 
ANILINE REDS. 
 
 179 
 
 llhis manner is sent into market without any purification, under the name 
 " azaleine." 
 
 During the operation the mercuric nitrate is reduced to the metallic state. 
 Almost the whole of the mercury can be recovered, re-converted into nitrate 
 off mercury, and used afresh in the preparation of azaleine. The bulk of the 
 niitric acid can be recovered as an alkaline nitrate. Next to the arsenical 
 mtethod, this is the most economical procedure. 
 
 Lauth and Depouilly heat 6 to 8 parts of aniline to 150 — 160 C, with 
 1 part nitrate of aniline. The fire must be removed as soon as the rea&ion 
 be:comes lively, or the mass will ignite. After the expiration of several hours 
 a mass is obtained of a fine violet-red colour, which may be purified by 
 bonling with 20 parts of water, when the unconverted aniline rises to the 
 suirface of the liquid as a scum, and is removed. The solution is then filtered 
 thirough sand, and on cooling deposits a green paste with a metallic refledtion. 
 Thiis process yields only 7 to 8 per cent of colouring matters, and the purifi- 
 cattion is difficult. 
 
 jA. variety of other oxidising agents have been proposed, such as phosphate 
 ancd acetate of mercury, nitrate of lead, free nitric acid, aqua-regia, nitrate of 
 anttimony, iodine, iodide of mercury,— in facl almost every metallic salt. The 
 expanse and inconvenience of most of these processes has caused them to be 
 quiietly abandoned, and prevented an immense amount of litigation. A recent 
 proposal deserves serious attention. Aniline is heated with nitro-benzol. 
 Thie yield is asserted to be very large, the process simple, and the subsequent 
 purrification easy. 
 
 By far the largest part of the magenta of commerce is prepared by the 
 arstenic acid process, which we shall therefore describe in some detail. 
 
 A\. commercial aniline is selected, containing as nearly as possible 3 parts of 
 anilline with 1 of toluidine, which is obtained by mixing 75 per cent of 
 kup>haniline and 25 per cent of baraniline : 800 kilos, of this aniline and 1370 
 kilos, of a solution containing 72 per cent of anhydrous arsenic acid are 
 introduced into the apparatus (Fig. 15). The still, capable of holding 
 250CO litres, is fitted with a stirrer, worked by steam-power. A wide tube 
 descends, parallel with the axis of the agitator, to the bottom of the 
 apparatus, and serves to introduce steam. In the upper part are a man-hole, 
 a saifety-valve, and a tap in communication with a tank of hot water. Below 
 are (two large holes for emptying. The neck of the still communicates with a 
 largee worm, which serves to condense the aniline volatilised in the course of 
 the process. The temperature should not exceed 190 to 200 C. The 
 operation lasts 8 to 10 hours. When the transformation is complete, about 850 
 litress of a mixture of aniline and water will have been condensed and col- 
 lectetd, which, if separated by the addition of common salt, yield 440 kilos, of 
 anilime and 420 of water. When 800 litres of the mixture have passed over, 
 the ffire is withdrawn, as the apparatus will still retain heat enough for the 
 termiination of the process and for completing the volatilisation of the free 
 anilime. During this time the agitator must be kept in constant motion. 
 Stearm is now allowed to enter by the descending tube, and sweeps away 
 mechianically the raw aniline yet remaining in the still. By degrees boiling 
 waterr is now introduced, whilst heat is again applied to the apparatus. When 
 the imass has become a homogeneous liquid, which is effected in about an 
 
 N 2 
 
I I Hi 
 
 180 
 
 DYEING AND CALICO PRINTING. 
 Fig. 15. 
 
 1. Elevation of complete apparatus. 2. Section. 
 Body of retort. b b. Head of retort. C. Axle of agitator, made hollow so as to 
 conduct steam to the bottom of the apparatus. c. Entrance for steam. J. Man- 
 hole, g g. Openings for taking out the colour. h h. Cavities in which hot air 
 circulates, and which can be opened if it is required to cool the apparatus. 
 
 Fig. 16. 
 
 ~W 
 
 hour, the vent-holes are opened, and the contents run into cisterns fitted with 
 agitators through sheet-iron pipes (Fig. 16). Here the mass is treated with 
 boiling water, in the proportion of 300 kilos, of crude magenta to 1500 litres 
 of water, acidulated with 3 kilos, of hydrochloric acid. Ebullition is kept up 
 bv means of steam-pipes. In four or five hours the solution is complete. 
 
ANILINE REDS. 
 
 1S1 
 
 TThe liquid is run, through large filters of woollen cloth, into large sheet-iron 
 rareservoirs, holding 8 to 10 cubic metres each, and so arranged that their con- 
 teents can be heated by currents of steam. The filtrate, which no longer 
 ccontains any matters insoluble in water, consists of solution of hydrochlorate, 
 anrsenite, and arseniate of rosaniline, along with free arsenious and arsenic 
 acicids. It is now necessary to eliminate the arsenic. For this purpose, and 
 fo'or every 200 kilos, of raw colour, 240 kilos, of common salt are added to the 
 liiiquid in small quantities at a time. The decomposition is accelerated by 
 bblowing in steam, the final result being hydrochlorate of rosaniline, and, on 
 thhe other hand, arsenite and arseniate of soda. The rosaniline compound, 
 hoeing insoluble in strong saline solutions, separates out and rises to the 
 suurface. The liquid is cooled, the colour collected, and, after a few days, the 
 mnother-liquor is run into large tanks, where it deposits the small amount of 
 ccolouring matter still held in suspension. 
 
 The colour thus obtained is washed with boiling water, in small quantities, 
 too remove the chloride of sodium and the bulk of the arsenical salts which 
 it t still retains. 
 
 If a higher degree of purity is required, it is re-dissolved in boiling water, 
 fililtered, and allowed to crystallise. 
 
 There is a method of effecting the solution of the crude aniline red uncle, 
 pruessure. This procedure saves time and labour, lessens the quantity of watei 
 enmployed, giving consequently a more saturated solution, and abridging the 
 fihltrations. The apparatus is represented in Fig. 17. 
 
 The colour thus obtained is the hydrochlorate of rosaniline, a base having 
 thne composition C 2 oH I gN 3 ,H 2 0. This base, when uncombined, pure and 
 cryystalline, appears in the form of small tables or needles, which if preserved 
 froom the action of the air are colourless, but redden rapidly on exposure. It 
 paasses from a colourless state to a rose, or even red condition, on fusion, 
 wi'ithout any change of composition. It is inodorous in the cold, but when 
 heaated gives off a scent of diphenylamine. Its taste is rather bitter. Its 
 spoecific gravity is r8. It melts in boiling water, and is decomposed at 220° C. 
 If ' kept for ten hours, or upwards, at the temperature of 210 to 220 C, it is 
 graradually transformed into a violet colouring matter, insoluble in water, and 
 bunt sparingly soluble in acetic acid and boiling alcohol. Rosaniline dissolves 
 in i boiling water to the extent of 2 or 3 grammes per litre, and is chiefly re- 
 depposited as the liquid cools. A litre of ammonia dissolves 4 grammes. In 
 sodda and potash lyes it is soluble to about the same extent. Lime-water 
 disssolves 3 grammes, and baryta-water rather more. In alcohol it dissolves 
 to the extent of 10 grammes per litre. Wood-spirit, acetone, carbolic acid, 
 andd aniline dissolve it freely ; the latter in all proportions. On the other 
 hannd, it is insoluble in ether, benzol and its homologues, and bisulphide of 
 carbbon. It is soluble in almost all acids, mineral and organic, forming well- 
 definned salts, which crystallise with great facility. 
 
 RRosaniline is a powerful base, displacing ammonia from its combinations 
 witlth acids at ioo° C. The coloured solutions of rosaniline and of its salts 
 are : completely decolourised by caustic and carbonated alkalies, but the colour 
 is reestored by the addition of a sufficient quantity of an organic acid. Proto- 
 chlooride of tin decolourises them at ordinary temperatures. Free chlorine 
 first t changes the colour to blue, and then destroys it. Chloride of lime rapidly 
 
-^■^BBB^BBBBBI 
 
 i, 2,3. Elevation, profile, and ground plan of the entire apparatus. 4. Section of a filter. 
 5, 6. Elevation and section profile of one end of the extraftion-boiler. 
 
 Boiler containing crude magenta melt and water, which are heated to about 130 C. 
 (pressure about 2 atmospheres). b. Spiral agitator. c. Filter working upwards, under 
 pressure from the boiler. d. Valve for opening or shutting communication between the 
 boiler and the filter, e. Tube conducting the liquid at will into the vats, f,g, h. These are 
 placed at different heights. In / a part of the colour is deposited ; a further portion settles 
 in g, and almost the whole remainder in the crystalliser, h, whence the liquid flows into the 
 well, i, from which it is drawn up by the pump,.;', for a new operation. 
 
ANILINE REDS. 
 
 183 
 
 decolourises the salts of rosaniline. Permanganate of potash transforms the 
 solutions of rosaniline and its salts into liquids which give merely a yellow 
 dye. Rosaniline, whether free or in combination with acids, if dissolved and 
 submitted to prolonged ebullition along with oxidising agents, — such as per- 
 oxide of lead, bichromate of potash, alkaline and alkaline earthy nitrites, and 
 peroxide of barium, — is transformed into other colouring matters, brown or 
 orange-red, according to circumstances. 
 
 The hydrochlorate of rosaniline, known as fuchsine, as obtained by the 
 above process, although sufficiently pure for many operations in dyeing and 
 printing, requires for certain purposes further purification. 
 
 The simplest manner of preparing free rosaniline is to dissolve the hydro- 
 chlorate in boiling water, and to decompose it by means of a slight excess of 
 an alkaline solution, also boiling. Ebullition is kept up for some hours ; the 
 liquid is filtered, and on cooling deposits magnificent crystals of rosaniline, 
 almost colourless. 
 
 The acetate of rosaniline, known commercially as roseine, is the most im- 
 portant salt of this base. The rosaniline employed in its preparation should 
 be pure and crystalline. It must be completely freed from the excess of alkali 
 used in its preparation, dried, and pulverised. The acid should be entirely 
 crystallisable, perfectly pure, and free especially from sulphuric and sulphurous 
 acids. Calcareous waters should also be avoided. The rosaniline, fresh from 
 the drying-stove, is placed in vessels of enamelled cast-iron, heated in the 
 water-bath or by steam. Acetic acid is very gradually added, the mixture 
 being carefully stirred till it becomes quite homogeneous. To promote com- 
 bination the whole is heated to 6o° or 70 C. Boiling water is then rapidly 
 poured upon the semi-fluid mass, and it is kept in ebullition for some minutes. 
 The liquid is run into crystallising vessels, set in a cool place not subject to 
 variations of temperature, and after standing a few days deposits fine crystals 
 of roseine. The best proportions are 20 parts of crystalline acetic acid to 
 100 parts of rosaniline. To dissolve these 120 parts of acetate of rosaniline, 
 240 to 250 parts of water are needed. The heat must be carefully managed, 
 to avoid loss of acetic acid by volatilisation. Too prolonged boiling wastes 
 the acid, and determines the formation of sub-salts which cannot be made to 
 crystallise. 
 
 Roseine can also be formed by double decomposition, adding the solution 
 of the crude arseniate, sulphate, &c, of rosaniline to a solution of acetate of 
 lead. The method is unprofitable, as the precipitated lead forms a lake with 
 a part of the colouring matter, which is thus practically lost. 
 
 Violaniline, mauvaniline, and chrysotoluidine are invariably present in small 
 quantity in crude rosaniline as prepared by the arsenical method. These 
 bases form collectively about one-half of the colouring matter contained in 
 the crude product. When separated they furnish useful dyes. For the 
 process of their isolation we must refer the reader to the work of Girard and 
 De Laire, " Traite" des Derives de la Houille," p. 575. 
 
 We must now turn to the practical application of magenta in dyeing and 
 printing. It is abundantly used, not merely in rose, pink, and red shades, but 
 in a variety of compound colours. Like most of the coal-tar colours, it has 
 a strong affinity for animal tissues, upon which it produces solid shades with- 
 out the aid of a mordant. Vegetable fibre, on the other hand, acquires merely 
 
sssssss? 
 
 
 W&$&W$ w& mi—I— — b 
 
 184 DYEING AND CALICO PRINTING. 
 
 a fugitive stain, and requires, therefore, the intervention of a mordant. The 
 first step is the solution of the colour. One of the best methods for woollens 
 is to arrange a small flannel filter at one corner of the dye-beck, with its bag 
 dipping below the surface of the liquid, but with its edges above. The re- 
 quisite quantity of magenta crystals is weighed out, wrapped carefully up in 
 a piece of clear flannel or close-grained calico, and allowed to dissolve in the 
 hot water. 
 
 It is very important that no particles of undissolved magenta should be 
 allowed to escape into the dye-bath, as they will attach themselves to the 
 goods and form intense red or even bronzed spots. This precaution is par- 
 ticularly necessary in piece dyeing. As the affinity of magenta for woollen 
 tissues is very great, without care the shades produced will be uneven. It is, 
 therefore, well to dissolve only part of the requisite amount of magenta at 
 once, wincing the pieces very rapidly in the weak-coloured liquid. The 
 pieces or yarns are then lifted out of the dye-beck, the rest of the colour 
 dissolved, the goods re-entered, and worked till the required shade is obtained. 
 
 For silk and cotton dyeing, where the dye-beck is not at so high a tem- 
 perature, and where, consequently, the magenta cannot be readily dissolved 
 in the manner above mentioned, the colour is previously dissolved and added 
 to the dye-bath. When the aniline colours were first introduced the magenta 
 crystals were dissolved in hot alcohol or methylated spirit, boiled for about a 
 quarter of an hour, very carefully filtered through flannel, and preserved till 
 wanted in stoppered bottles. In dyeing, the necessary amount of this 
 solution was added to the dye-beck. This method was open to several dis- 
 advantages, as the cost of the alcohol, and its gradual evaporation during the 
 process of dyeing, when the magenta was apt to separate out as a bronze 
 scum, and to soil the tissues. Worst of all, the employment of a large 
 quantity of alcohol was found to render the colours flat and dull. Great care 
 is needed in the selection of a commercial alcohol for use along with magenta. 
 It must be free from shellac — a common impurity. If this is present the 
 colour works flatter and has a bluish tone, which is not desirable. Shellac 
 may be easily detected by adding a little of the suspected spirit to an excess 
 of water when the shellac is deposited. Pure alcohol when heated with 1 per 
 cent of pure caustic potash should turn a bright yellow. If it becomes brown 
 it should be rejected as contaminated with fusel and empyreumatic oils, which 
 have an injurious effect in dyeing. 
 
 Some dyers dissolve magenta in acetic acid, which takes it up very readily, 
 but gives it a biue shade. A good method is to reduce the magenta crystals 
 to fine powder, rub them well up with their own weight of alcohol, and allow 
 the mixture to stand overnight in a closed vessel. In the morning the paste 
 thus obtained is mixed with the smallest needful quantity of boiling water, 
 boiled up for a few minutes and filtered into the dye pan through flannel. 
 
 Another method is to rub up the magenta in glycerine, and then boil in 
 the smallest quantity of water needful to dissolve it, and filter for use. 
 Glycerine is preferable to alcohol, because it does not evaporate, prevents 
 " bronzing " on the surface of the tissues to be dyed, and has no " flattening " 
 effect upon the colour. Indeed, were it not for its high price it would be 
 largely added to the dye-bath in almost every case where aniline colours 
 are employed. 
 
ANILINE REDS. 
 
 i «5 
 
 Magenta can also be dissolved in certain saline liquids, such as solutions 
 of bicarbonate of soda, carbonate and bicarbonate of ammonia, and borax. 
 These solutions dye redder shades than magenta dissolved in alcohol, glycerine, 
 or water — an effect which can be, to some extent, also produced by adding a 
 little white soap to the dye-bath. On the other hand, if it be desired to pro- 
 duce a more blue tone, a little tartaric or sulphuric acid is added. 
 
 In cotton dyeing a mordant is needed to cause the magenta to be firmly 
 fixed upon the fibre. The selection is governed by the circumstances of the case. 
 
 If the article to be dyed consists entirely of cotton, whether in the state of 
 yarn, or of a woven tissue, it may be prepared as for Turkey-red, or worked 
 for a couple of hours in a decoction of commercial tannin, of good nut-galls, 
 or of pale myrobalans,* or any other substance rich in tannin, but free from 
 colouring matters. The cotton goods are then taken out of the tannin liquor, 
 allowed to drain for a short time, and then worked in a weak solution of 
 stannate of soda for about an hour. Next they are passed through water 
 slightly acidulated with sulphuric acid, or with alum. They are then rinsed 
 in pure water and worked in the magenta solution at ordinary temperatures 
 to the shade required. Some dyers vary the order and apply the stannate 
 of soda first and the solution of tannin afterwards. 
 
 Another process is to work the cotton yarn in a solution of the subacetate 
 of lead, and afterwards in a solution of soap. 
 
 In piece-dyeing, where the weft is wool or worsted, and the warp cotton, a 
 different procedure is necessary. The pieces are winced first in an infusion 
 of gall-nuts or other similar material, and then in a solution of tin-crystals. 
 The pieces are then rinsed in water and transferred to the colour-bath. Some 
 dyers omit the tannin-bath lest it soil the wool, and others use instead of the 
 tin-crystals a peculiar nitro-muriate of tin, which will be subsequently 
 described as " Aniline Mordants." 
 
 In printing, magenta is applied to calico with albumen, and thickened with 
 starch or gum. " Lactarine " (caseine) may also be used instead of albumen 
 when no additional thickening is needed. In either case the goods after 
 printing are steamed from thirty to sixty minutes. 
 
 Another method, invented by Schultz, is to mix \ litre of acetate of alumina 
 at io° of Baume's hydrometer with 20 grms. arsenite of soda to every 4 grms. 
 of magenta. This mixture is thickened with starch which has been boiled 
 separately. The quantity of starch is increased the lighter the shade 
 required. In printing this composition is mixed with the amount of colour 
 required, and the goods are afterwards steamed. 
 
 The red in the accompanying pattern is magenta, fixed as above mentioned. 
 The violet is Hofmann's (see below) ; the green, chrome-green, both fixed in 
 the same manner as the magenta. The black is a so-called chrome-black, a 
 mixture of logwood and bark-liquor, with chlorate of potash and acetate of 
 chromium for mordant, thickened with starch and gum, and steamed. 
 
 Examination of Magentas. 
 The simplest method of testing a commercial sample of magenta, both for 
 intensity and for purity of tone, is tfo dissolve a known weight in boiling 
 
 * Contrary to an old prejudice, myrobalans are preferable to the best sumac, as they contain 
 an oil which assists in the fixation of aniline colours. 
 
DYEING AND CALICO PRINTING. 
 
 
 f 
 
 
 h 
 
 £3* 
 
 
 11 
 
 
 Magenta. 
 
 water and to dye with the strained decoction a known weight of fine white 
 woollen yarn or cloth. By thus comparing different samples, their respective 
 tinctorial power can be readily ascertained, and the presence of tarry matters, 
 unconverted aniline, &c, may be detected by the flatness and brownish cast 
 of the colour. Sugar is sometimes used as an adulterant. This may be 
 detected by treating the sample with concentrated alcohol. The magenta 
 dissolves and is filtered off, whilst the sugar remains behind undissolved. 
 
 The following method is used to ascertain whether a magenta is a pure salt 
 of rosaniline or is contaminated with mauvaniline, violaniline, chrysotoluidine, 
 &c. The colour is dissolved in as little alcohol as possible, the solution 
 diluted with its own bulk of water or rather more, and a drop is taken up by 
 
 Ponceau. 
 
PERKIN'S VIOLET, OR MAUVE. 
 
 187 
 
 means of a glass rod and applied to a piece of white blotting-paper. If 
 more than one colouring matter is present the different shades will diffuse 
 themselves in concentric circles and may be distinctly seen. This method is 
 still more applicable to the aniline violets and blues, which are frequently 
 heterogeneous. 
 
 Aniline Crimson. 
 
 The crude magenta-cake without any purification is sold under this name, 
 and is used in dyeing certain maroons, browns, clarets, and other compound 
 colours. 
 
 The colour, well bruised or broken up into powder, is placed in a suitable 
 stoneware vessel and well stirred up with its own weight of hydrochloric acid. 
 During this process the fumes given off should be carefully avoided. After the 
 colour has steeped for a short time in the acid, boiling water is added sufficient 
 to dissolve the whole. The solution thus obtained is carefully strained, and is 
 then ready for use. To correct the acidity of the colour a small quantity of 
 ammonia is added to the dye-bath. This preparation will in many cases 
 supersede peachwood, producing brighter shades, with less trouble, and at a 
 lower price. They are, however, more fugitive. Upon wool and silk aniline 
 crimson, like magenta, is a substantive colour. Upon vegetable fibres it requires 
 to be fixed with a mordant — generally a per-salt of tin — and an astringent. 
 
 Ponceau. 
 
 This is the trade name of an aniline colour manufactured by the eminent 
 firm of Brooke, Simpson, and Spiller (late Simpson, Maule, and Nicholson). 
 The process by which it is obtained is secret. The colour is redder than the 
 reddest shade of roseine, appears exceedingly bright by artificial light, and is 
 considered faster than the magentas. It is a substantive colour on wool and 
 silk, the only precaution required in dyeing being to add the colour very 
 gradually to the neutral bath, and work slowly up to the required shade. No 
 previous mordanting or other preparation is necessary. The tone can, if 
 needed, be varied by the addition of a little ammonia. 
 
 The aniline violets include a formidable list of colours, unlike in their 
 preparation, constitution, and properties, and sold under such names as 
 mauve, harmaline, parma, dahlia, primula, indisine, rosolane, violine, phe- 
 nameine, &c. 
 
 Perkin's Violet, or Mauve. 
 
 The earliest aniline colour introduced into commerce has lost much 
 of its importance. Runge had previously called attention to the violet 
 colouration produced on treating aniline with chromic acid or the hypochlorites. 
 In August, 1856, Mr. Perkin patented his process for the production of a violet 
 colouring matter from aniline. 
 
 The production of this violet or mauve colour depends upon the action of 
 oxidising agents upon aqueous solutions of salts of commercial aniline. The 
 violet or mauve of commerce contains a powerful organic base now called 
 Mauveitie, soluble in alcohol, with a dingy violet colour. The development of 
 the mauve is the result of the union of this base with an acid. The colouring 
 matter generally used is the acetate of mauveine, a salt which may be obtained 
 in fine crystals of a green metallic lustre. Mauveine has so great an affinity 
 
MUbUHH 
 
 sffitf&mmffi^&s^&si 
 
 
 WWlHBl hmmwpb 
 
 i 88 DYEING AND CALICO PRINTING. 
 
 for even the most feeble acids, that the dull colour of its alcoholic solution 
 rapidly changes to purple under the influence of the carbonic acid of the 
 breath. Mauveine is decolourised by nascent hydrogen, but its original colour 
 is instantaneously restored by the oxygen of the air. The mauve of commerce 
 is usually a brownish violet-coloured paste, very sparingly soluble in cold 
 water, somewhat more so in hot water, but readily soluble in alcohol, wood- 
 spirit, aceton, in the acetic, sulphuric, hydrochloric, and tartaric acids, in 
 glycerine and aniline. This substance may be obtained in crystalline form 
 when its solutions are evaporated to dryness. The crystals exhibit, especially 
 after having been washed with some ammoniacal water, a brilliant green 
 colour. Mauve is precipitated from all its solutions by water, especially 
 if the latter contains neutral alkaline salts, caustic alkalies, or metallic salts. 
 If the paste or solid mass is placed upon a strongly-heated metallic plate red 
 vapours are given off, and volatilisation appears to take place ; but even 
 in vacuo no sublimate is obtainable. When mauve is treated with rather con- 
 centrated hydrochloric or sulphuric acid it is converted into a blue-coloured 
 mass, which a larger addition of acid renders green. On the addition of water 
 the blue colour is first brought out again, and after a while the violet is 
 restored. When mauve is boiled with dilute nitric acid there is formed 
 a yellow-coloured liquid, and a reddish pulverulent mass scarcely soluble in 
 water is precipitated. Chlorine water discolours the alcoholic solution, but 
 its colour is restored by the action of sulphuric acid. According to M. Scheurer- 
 Kestner, the composition of mauve is represented by the formula C20H14N3, 
 and it therefore only differs from rosaniline (C 2 oHi g N 3 ) by containing less H. 
 This view is not that of the celebrated discoverer of mauve, Mr. Perkin, 
 who says that the material obtained by the action of bichromate of potassa 
 upon sulphate of aniline is the sulphate of an entirely new base, mauveine, 
 C 2 7H 24 N 4 . This base is prepared from the crystalline mauve of commerce by 
 adding to its boiling solution a solution of caustic soda. By this proceeding 
 the purple colour of the solution of the mauve changes directly to a violet 
 blue, and when the solution is left standing a crystalline substance is deposited, 
 which after having been first washed with alcohol, and next with water, 
 exhibits after drying a brilliant blackish powder not unlike oligistic iron ore. 
 Mauveine is soluble in alcohol, yielding a violet-coloured solution, which on 
 the addition of an acid is converted into a purple colour. Mauveine is almost 
 insoluble in ether and benzol, and is a strong base which even decomposes 
 ammoniacal salts. When subjected to a high temperature decomposition takes 
 place, and an oily basic substance ; s obtained distinct from aniline. Mauveine 
 forms a series of salts, all of which have been carefully studied and described 
 by Mr. Perkin, and which are nearly all rather hygroscopic. The salts of the 
 mauveine, or indisine of commerce, are usually prepared by means of the 
 oxidising action of suitable materials upon the salts of aniline of commerce 
 (mixtures of aniline and toluidine) in aqueous solution. The method adopted 
 for the preparation of mauve is as follows : — ioo kilos, of heavy aniline are mixed 
 with 54 kilos, of concentrated sulphuric acid and 2 kilos, of water. The 
 acid thus diluted is added to the aniline little by little with constant stirring. 
 When the whole has been poured in, the mixture is heated and stirred so as 
 to obtain a homogeneous liquid, and is then allowed to cool. When cold 
 add 140 kilos, of bichromate of potash dissolved in the smallest possible 
 
PERKIN'S VIOLET, OR MAUVE. r 8 9 
 
 quantity of water, and allow the reaction to proceed for twenty-four hours. 
 T'he mixture becomes turbid, blackens, and at the end of the period has 
 reesolved itself into a clear liquid, and a black precipitate containing mauveine 
 (iindisine), chromic oxide, and certain resinous impurities. The large wooden 
 vessels in which this process takes place are then filled up with boiling water. 
 T'he whole is well stirred up and allowed to settle. The water, which contains 
 thie excess of bichromate of potash and certain soluble impurities, is then 
 caarefully decanted off. The washing is thus repeated four times, and the 
 bllack precipitate containing the colouring matter is then collected upon filters. 
 It is washed twice or thrice with water slightly acidulated with sulphuric acid 
 amd then with cold water. The precipitate is then boiled with water in large 
 vaats for three hours and often stirred. The liquid, which holds the colouring 
 miatter in solution, is drawn off by decantation and filtration. This treatment 
 is repeated until nothing more can be dissolved. These aqueous solutions, 
 miixed and filtered, are precipitated by an alkali or an alkaline salt. The 
 prrecipitate, collected on a filter, is washed with luke-warm water to remove 
 exxcess of the precipitating salt and a certain reddish colouring matter. It is 
 fimally converted into acetate of mauveine by the addition of the necessary 
 qiuantity of acetic acid. To obtain the acetate pure, this process of solution 
 prrecipitation, and washing must be several times repeated. By this pro- 
 cedure ioo kilos, of baraniline yield 75 to 90 kilos, of mauve in the state of 
 thiick paste. 
 
 The selection of aniline is a very essential matter for the preparation of 
 miauve. The anilines suitable for it are not the same as those which give the 
 bc-jst results for magenta. The mauve prepared according to the process just 
 described, though fit for practical purposes, is not chemically pure. If required 
 ini this state it must be boiled in a large quantity of water, and then filtered. 
 Firom the solution the colouring matter is thrown down by means of an alkali. 
 Tlhe precipitate thus obtained should be collected upon a filter, washed with 
 wrater until free from alkali, and dried. When dry it is to be dissolved in 
 absolute alcohol, the solution filtered, and then evaporated to dryness on a 
 waater-bath. The mauve thus obtained is a brittle substance, with a beautiful 
 brmnzed surface ; but if some of its alcoholic solution be evaporated on a 
 gkass plate, and viewed by transmitted light, it is of a fine bluish-violet. 
 Miauve forms a remarkable compound with tannin. If an aqueous solution 
 is mixed with a solution of tannin, precipitation takes place ; the pre- 
 cipitate, after having been well washed, no longer possesses the properties of 
 thee pure colouring matter, but is insoluble in water, and dissolves in concen- 
 traated sulphuric acid, forming a dirty green liquid; but on adding an excess of 
 waater to this solution the new compound is precipitated unchanged. With 
 thtese tannates dissolved in acetic acid, Messrs. Clift, Lowe, and Calvert dyed 
 spcecimens of silk, wool, and cotton, which the latter gentleman exhibited 
 eairly in the year 1858 before the Society of Arts. 
 
 Among the very large number of new methods proposed for the manufacture 
 of this dye, especially after the spring of the year 1859, we may notice the 
 folllowing : — Messrs. Depouilly and Lauth's method (patented in June, i860) con- 
 sisted in adding to a salt of aniline a solution of chloride of lime, which yielded 
 a purple insoluble precipitate. This was repeatedly washed in slightly acidulated 
 ivaater, dissolved in concentrated sulphuric acid, and re-precipitated by the 
 
— — — mHBB 
 
 igo 
 
 DYEING AND CALICO PRINTING. 
 
 addition of an excess of water. It was then simply necessary to wash the precipi- 
 tate thoroughly, in order to render it fit for use if dissolved in alcohol or methyl- 
 ated spirit. The chloride of lime process gives a more abundant yield than the 
 bichromate method, but the tone of the violets obtained is redder and less 
 pure. We may here mention that Mr. W. H. Perkin has lately succeeded in 
 obtaining the product of Runge's experiment in the solid condition. He finds 
 that it dissolves in alcohol, forming a solution of a nearly pure blue colour, 
 which is changed to a brownish-red by the action of caustic alkali ; it there- 
 fore differs essentially from the mauve, an alcoholic solution of which, if 
 treated with caustic alkali, passes from purple to violet, The blue producl, 
 which the author proposes to call " Runge's blue," undergoes a very remark- 
 able change when subjected to the action of heat. It is rapidly converted into 
 a purple cclcuring matter, which is found to be the true mauve. Indeed 
 Runge's blue is so prone to change into the more stable mauve that its compo- 
 sition cannot be satisfactorily determined. Mr. Kay, in January, i860, took out 
 a patent for producing purple-aniline, — most absurdly called " harmaline," — 
 by adding to sulphate of aniline peroxide of manganese, and heating this 
 mixture to ioo°, when the " harmaline " so produced remained in solution, 
 and was separated from an insoluble deposit. The dissolved colour was pre- 
 cipitated by adding to the solution ammonia in sufficient quantity to neutralise 
 the acid, after which the insoluble colour was washed, dried, and dissolved in 
 methylated alcohol. In January, i860, Mr. Greville Williams patented the use 
 of permanganate of potassa as a means of oxidising aniline and producing 
 purples and other colours ; at about the same time Mr. D. Price took out a 
 patent for acting on sulphate of aniline by means of the peroxide of lead. 
 In i860 Dale and Caro patented the use of chloride of copper, in the propor- 
 tion of 6 equivalents to 1 of a neutral salt of aniline. In place of chloride of 
 copper, a mixture of sulphate of copper and common salt may be used in 
 equivalent proportions. The quantity of water necessary to dissolve the 
 mixture is added, and the whole is then boiled till a precipitate appears, which 
 contains the colouring matter. At the expiration of three or four hours the 
 process is completed. The precipitate is collected on a filter, and washed 
 with a solution of soda or carbonate of soda so long as the washings contain 
 chlorides. The residue is then extracted with boiling water so long as any- 
 thing dissolves. The solutions thus obtained are filtered, and precipitated 
 with a small quantity of soda or carbonate of soda. The colour thus 
 obtained is ready for use. The matter insoluble in boiling water still contains 
 a violet, which may be extrafted hy treatment with boiling dilute alcohol in a 
 displacement apparatus. 
 
 On the 12th of January, 1861, another interesting process to obtain aniline 
 purple was patented by M. A. Girard : pure aniline red (known as magenta) 
 is mixed with an equal weight of aniline, and the mixture heated for several 
 hours to 329 F., when the mass is changed to a fine purple colour, requiring 
 only to be mixed with water and hydrochloric acid to remove any aniline or 
 red dye in excess, leaving the purple insoluble ; but on being well washed 
 with water this becomes soluble in alcohol, acetic acid, wood naphtha, and boiling 
 water, slightly acidulated with acetic acid. The French call this Violet 
 Imperial. 
 
 In 1862 Mr. G. C. Nicholson secured a patent for producing a very beautiful 
 
PERKIN'S VIOLET, OR MAUVE. 
 
 191 
 
 colour, named Regina purple. The following is a full description of his 
 process : — " I take red dye, such as is made from aniline or its homologues, 
 amd, without the admixture of either aniline or its homologue, I heat it carefully, 
 in a suitable apparatus, to a temperature by preference between 3go° and 420 F. 
 Tlhe substance quickly assumes the appearance of a dark semi-solid mass, the 
 reed dye being transformed into a dark substance with evolution of ammonia. 
 Tlhe mass I prefer afterwards to extract with acetic acid, using a quantity of 
 ac:id about equal in weight to the amount of the red dye treated, and this acid 
 I dilute with enough alcohol to make a dye of convenient commercial 
 strrength : the solution obtained is of a deep violet or purple colour, and may 
 be used directly for dyeing purposes. What I claim is the producing a violet 
 or purple colour from red dye, such as is made from aniline or its homologues, 
 by carefully treating it as described, without admixture either of aniline or its 
 homologue." M. Stark patented a method of producing this colour, by boiling 
 for - two or three hours a mixture of a salt of aniline with red prussiate of 
 pottassa, leaving the whole to cool, when a greyish-blue precipitate settles at 
 thes bottom. It is, however, not certain whether the colour thus obtained can 
 cormpete with those already used. The use of the red prussiate of potassa for 
 producing aniline purple had been mentioned by M. Emile Kopp before the 
 datce of M. Stark's patent. 
 
 TThe paste violet (mauve) is tested for its tinctorial value in the following 
 mamner : — 3 grms. are exactly weighed, and dissolved in 50 c.c. of acetic acid. 
 To this solution is" added a quantity of 100 grms. of gum-water (containing 
 500J grms. of gum to the litre), and next a quantity of 100 grms. of albumen- 
 watter (containing 500 grms. of albumen to the litre). This mixture is used 
 to [print, by means of the roller, stripes on muslin. After the printing the stuff 
 is dlried, steamed, washed, and compared with a standard sample. This assay 
 cam also be executed by a dyeing process in the following manner: — 2 grms. 
 of tthe paste are dissolved in 10 c.c. of alcohol (or methylated spirits), and 
 diliuted with water so as to yield a quantity of 1 litre ; 50 c.c. of this liquid 
 are taken, and diluted to a 4 litre. This fluid is brought to ebullition, and in 
 it 5; grms. of wool are dyed, so as to exhaust the bath. The purples above 
 memtioned, when fixed on woven tissues, are recognised by the following 
 reaidtions, it being remembered that these colours can only be perhaps confused 
 witlh the rosaniline violet and French purple (a peculiar orchil colour — to the 
 forrmer the Regina violet, just spoken of, belongs) : — (1). When, acted upon with 
 strong mineral acids (sulphuric or hydrochloric) the dye in question turns blue. 
 (2). Caustic alkalies do not act upon it in the cold. (3). A solution of sul- 
 phuirous acid in water into which a piece of sheet zinc is placed causes the 
 imrmediate decolouration of any tissue thus dyed. 
 
 A series of aniline violets, sold under a number of fanciful names, are ob- 
 tainied from rosaniline by the process of phenylation, — that is, one or two atoms 
 of tlhe hydrogen present in the rosaniline are replaced by the same number 
 of eiquivalents of phenyl or of tolyl. The conversion of the red into a violet 
 is ejected in an enamelled iron retort, holding about 20 litres, heated in a 
 paraiffin bath. The head is joined to the body by means of pressure-screws. 
 The head is made high to promote the re-condensation of the aniline, which 
 is vrolatilised. The retort is fitted with a mechanical stirrer, in the axis of 
 whicch lies a tube through which steam can pass. The mixtures used vary in 
 

 192 DYKING AND CALICO PRINTING. 
 
 proportion, according to the shade required. The more aniline is added the 
 more hydrogen is replaced, and the more the violet produced inclines to a 
 blue. The aniline employed should be as pure as possible. About equal 
 weights of magenta and aniline are employed, according to the original speci- 
 fication of Girard and De Laire. The retort is raised to a temperature of 
 165° to 190 C, and maintained there till the process is complete, which may 
 be in 60 to 90 minutes. The progress of the operation is observed by means 
 of a rod inserted at an aperture arranged for the purpose. A drop of the con- 
 tents being thus withdrawn is placed upon a white porcelain plate, mixed with 
 a little alcohol and acetic acid, and its colour examined. The redder 
 shade of violet is a mono-phenyl rosaniline, whilst the blue shade is diphenyl- 
 rosaniline. 
 
 The process is varied slightly by different manufacturers. Levinstein mixes 
 3 parts of aniline with 1 of magenta, and maintains the whole for three or 
 four hours at 180 C. A reddish shade is yielded by 100 parts magenta, 100 
 parts aniline, and 25 parts acetate of soda. As soon as the desired shade is 
 obtained the contents of the retort are run out and heated with very dilute 
 hydrochloric acid, which dissolves out any unconverted aniline that remains 
 in the mixture. The violet colour is left floating on the surface of the 
 liquid. It is strained off, freed from traces of acid by washing with water, 
 dried, and powdered. The red-violet very much resembles solid magenta in 
 appearance, but is less green. The bluer the violet the more of a coppery-red 
 is its reflection. In the production of the very bluest violets soap is often 
 employed. A favourite mixture is 100 parts aniline, 300 magenta, 
 75 acetate of soda, and 66 of a good curd soap. Prolonged heating, even 
 with one and the same mixture, gives the result a bluer tone. The yield is 
 greater than the weight of the magenta employed. 
 
 These violets are insoluble in water, either hot or cold. They dissolve in 
 alcohol, wood-spirit, aceton, acetic acid, and concentrated glycerine. The 
 use of these violets has very much diminished since the methylated and 
 ethylated substitution-products of rosaniline — -the so-called Hofmann and 
 Paris violets — were discovered. 
 
 Of the Hofmann violets, chiefly manufactured by Messrs. Brooke, Simpson, 
 and Spiller, there are a variety of shades, ranging from the reddest (R.R.R.) to 
 the bluest (B.B.B.). These marks correspond to certain different grades 
 of substitution, ethyl or methyl here taking the place of hydrogen, in the 
 rosaniline atom for atom. The shade R.R.R. consists chiefly of mono- 
 methylated rosaniline, whilst B B B, is almost exclusively composed of tri- 
 methylated. The apparatus employed on the Continent in the manufacture 
 of these colours is represented in Fig. 18. It is a boiler of enamelled iron, 
 made strong enough to bear a pressure of 20 to 25 atmospheres, and varying 
 in capacity from 80 to 100 litres. It may be heated either on the water-bath 
 principle or by means of a steam-jacket. It is fitted up with a thermometer 
 and a pressure-gauge. 
 
 For a red violet, " R.R.R.," the materials are — 
 
 Rosaniline 10 kilos. 
 
 Alcohol 100 litres. 
 
 Iodide of methyl or ethyl 8 kilos. 
 
 Hydrate of potassa or soda 10 ,, 
 

 
HOFMANN'S VIOLET. 
 Fig. 18. 
 
 193 
 
 Elevation and Section of the Apparatus. 
 a, b. Boiler and its cover. c. Steam-jacket, fed and emptied by the pipes d d. 
 f. Pressure-gauge. g. Cylinder, with two taps for introducing matters into the 
 apparatus without diminishing pressure. h. Screw- or valve-tap, to permit the 
 vapours to enter a warm condenser. i. Pipe to run off the steam-jacket. 
 
 The mixture is heated to 115° to 130 C, for about two hours. 
 For a blue violet, " B " shade, the mixture is — 
 
 Rosaniline 10 kilos. 
 
 Alcohol 100 litres. 
 
 Iodide of methyl .. 5 kilos. 
 
 Iodide of ethyl 5 ,, 
 
 Potassa 10 ,, 
 
 For a bluer shade, " B.B. " — 
 
 Rosaniline 10 kilos. 
 
 Iodide of methyl 20 ,, 
 
 Alcohol 100 litres. 
 
 Potassa 10 kilos. 
 
 The alcoholic solutions of the iodides and of potassa are introduced in suc- 
 cessive portions during the operation. When the requited shade has been 
 obtained the contents of the still are drawn off and purified. For this 
 purpose the excess of alcohol is distilled off. The residue is then treated 
 with an alcoholic solution of soda, in an apparatus fitted up with an agitator 
 and a cohobator. It is then washed with boiling water in the same apparatus, 
 with constant agitation, in order to remove both the alkaline iodide formed and 
 the excess of soda. When thoroughly washed it is taken up in sulphuric, 
 
 o 
 
194 
 
 DYEING AND CALICO PRINTING. 
 
 hydrochloric, or acetic acid. The salt formed is dissolved in boiling water. 
 The solution is then filtered, and precipitated by the addition of common salt. 
 The pure colour is thus precipitated, and is collected on filters and dried. It 
 is perfectly soluble in pure water, even at common temperatures. 
 
 There are a variety of other analogous violets, as the mono-, di-, and tri- 
 methyl, and ethyl mauvanilines. They are prepared in a manner corresponding 
 to Hofmann's violets, and have a bluer shade. 
 
 The mono- and tri-methyl iodhydrates of trimethylated rosaniline are still 
 more nearly blue. 
 
 Lauth and Grimaux have formed a violet by causing benzyl to replace the 
 substitutionable hydrogen in rosaniline. There is also a methylic benzylic 
 and a phenylic methylic violet. 
 
 Perkin's "Britannia violet" is prepared in a very similar manner, by 
 treating 6 parts of rosaniline with 30 parts of methylic alcohol and 4 parts 
 bromide of terebene. 
 
 Hofmann's Violet (B). 
 
 The comparative strength, shade, and brightness of a violet are best ascer- 
 tained by dyeing patterns of known weight. Their pure or mixed nature may 
 be tested by placing a drop of the solution upon blotting-paper, as directed for 
 magenta. Instances occur where a violet consists of two portions, — the one 
 soluble in water and of a red colour, and the other dissolving only in spirit, 
 with a blue. Sometimes a considerable portion yields to no solvent employed 
 in dyeing, and on examination proves to be quite valueless. 
 
 Aniline violets maybe divided, as regards their application, into two classes 
 — the insoluble (in water) and the soluble. The former are dissolved in 
 methylated spirit, with the aid of heat, making the solution as strong as 
 possible. The substitution of glycerine for a part of the spirit will be found 
 to give very satisfactory results. Wood-spirit may be used in place of alcohol 
 where very blue tones are desired. Great care must be taken in filtering the 
 solutions. The soluble violets — those of Hofmann, Perkin's " Britannia," 
 and the " Paris violet " — are readily soluble in water, and have a greater 
 
ANILINE BLUES. 
 
 *95 
 
 affinity for cotton than most aniline colours. In some cases, where conve- 
 nience requires highly concentrated solutions, these colours also are dissolved 
 in alcohol, wood-spirit, or glycerine. 
 
 In dyeing the same general principles are observed as in case of magenta. 
 In Hofmann's violets for wool and worsted the goods should be entered at 
 i2o° F., and the temperature be very gradually raised up to 212° F. Great 
 care should be taken not to add an excess of colour, which is certain to 
 produce flushing or bronzing. The annexed specimen is dyed with Hofmann's 
 B., as prepared by Messrs. Brooke, Simpson, and Spiller. Cotton and 
 mixed goods may be dyed as directed for magentas. 
 
 The following method of fixing the aniline colours upon cotton is due to 
 Lloyd and Dale : — To 4J litres of gum-water we add 240 to 300 grms. of pure 
 dry tannin, and the colouring matter more or less according to the shade 
 required. After printing and steaming at a pressure of about 50 to 75 grms. 
 to the square centimetre, the pieces are then passed through a bath of 
 tartrate of antimony or bitartrate of potash and antimony (tartar-emetic), 
 containing 13* grins, of this salt to the litre, and heated to 45 to 85 C. The 
 goods are then rinsed and dried. A variation of the method is to print on the 
 calico a thickened solution of tannin (133 grms. of tannin to a litre of gum- 
 water for full, and 20 to 27 grms. for light shades). After printing, the pieces 
 are steamed for an hour, and passed into the antimonial bath. They are next 
 well washed and dyed in the colour-bath, which is slightly acidulated, and 
 heated slowly to the boiling-point, at which it is maintained for twenty 
 minutes. If after washing the white grounds are still faintly stained, they are 
 bleached by being passed through a weak solution of chloride of lime, and 
 afterwards through soap-lyes. 
 
 The addition of acids renders the tone more blue, but at the same time it 
 deadens the colour and impairs its affinity for the fibre, especially in case of 
 cotton. 
 
 ANILINE BLUES. 
 Paris Blue (Persor, De Luynes, and Co.), Lyons Blue (Girard and De Laiie), 
 Mulhouse Blue (Gros-Renaud), Azurine (Calvert and Lowe), Azulinc, 
 Rosaniline Blue, Bleuine, O xy phcnylanilide , Dioxyphenylanilide, Night 
 Blue, Methylaniline Blue, Triphenylic Rosaniline, Toluidine Blue, Roso- 
 toluidine Blue, Opal Blue, Regina Blue, Nicholson Blue, Guernsey Blue. 
 
 Lauth observed on December 24th. i860,* that when magenta, especially 
 azaleine, is heated with a reducing agent, such as protochloride of tin, a 
 purple and even a blue were obtained. In continuing these researches he 
 observed that a blue matter could be easily obtained by heating azaleine with 
 various organic compounds, such as aldehyde, several of the hydrurets of 
 benzyl, acetyl, and many natural essences. This blue colour cannot resist 
 the action of acids and of light, and is therefore practically useless. The 
 action of aldehyde and the composition of the blue itself have been investi- 
 gated by M. Willm, and are exhibited by the following formula : — 
 
 2 (C 3 r,I I,oN 4 Q 4 ) + 5C 4 H 4 02 + 8 H O = 3 , (C^H „NOa) + 5 C 4 H 3 (NH 4 )Q 4 . 
 
 Azaleine. Aldehyde. Blue, or Acetate of Ammonia. 
 
 Oxyphenylanilide. 
 
 See vol. xxxi. of the " Bulletin de la Sociele Industrielle de Mulhouse." 
 
 O 2 
 
ig6 
 
 DYEING AND CALICO PRINTING. 
 
 Therefore the triamine azaleine has been transformed into a monamine blue, 
 by a new chemical reaction ; for aldehyde not only ads as a reducing agent, 
 but converts a part of the nitrogen into ammonia. M. Lauth has also 
 obtained a blue colour similar to the above by acting on methylaniline with 
 bichromate of potassa. A blue also produced by the reduction of magenta, 
 but resisting the action of acids and also of light, was patented by Girard in 
 January, 1861, and is made by heating for several hours, at a temperature of 
 329'-' F., equal weights of magenta and aniline, and allowing the whole to 
 cool ; the substance produced is mixed with weak hydrochloric acid, which 
 removes excess of aniline and red dye, and leaves a purple colour, which is 
 further reduced into a blue colour by boiling it several times with a mixture 
 of hydrochloric acid and alcohol. It is then washed with boiling water. The 
 substance thus obtained is of a fine blue, with a coppery lustre. Bleu de Paris 
 is another instance of the reduction of magenta into a purple and blue. It is 
 prepared by heating for thirty hours, in a closed vessel, at a temperature of 
 356 F., 1 part of anhydrous bichloride of mercury with 2 parts of aniline. 
 The mass is then treated with boiling water, and precipitated by the addition 
 of common salt, this treatment being repeated several times until all traces of 
 a green colour are removed. The blue thus produced resists the action of 
 weak acids and alkalies, but assumes a red hue when acted on by these agents 
 in a concentrated state. Sulphurous acid has no action, and it dyes animal 
 fibres with facility. The formation of Bleu de Mulhoase is one of the most 
 interesting reductions of aniline red, in a commercial point of view. It was 
 invented by Messrs. Gros-Renaud and Schaiffer: in 1 litre of boiling water 
 they dissolve — 50 grms. bleached shellac ; 18 grms. carbonate of soda ; 50 
 grms. of a solution of azaleine, made up of 125 grms. of azaleine dissolved in 
 £ litre of water and \ litre of alcohol. The whole is kept at a boil for an hour, 
 care being taken to maintain the fluid at its original bulk by the addition of 
 water. 
 
 The most valuable and most scientific method of manufacturing aniline blue 
 is that discovered by M. Marnas, of the firm Guinon, Marnas, and Bonnet, of 
 Lyons, not only because it is based upon a novel chemical reaction, but also 
 because the blue is produced directly from aniline, which is gradually oxidised 
 into a blue by means of peunine. 5 parts of peonine are mixed with 8 parts of 
 aniline, and the whole heated to the boiling-point for some hours, until nearly 
 all the material is transformed into a blue colour, which is purified by suc- 
 cessive warnings ; the first with boiling water, acidulated with sulphuric or 
 hydrochloric acid ; the second, with hot oils of tar ; the third, with a diluted 
 solution of caustic alkali ; and the last with slightly acidulated water. The 
 azuline, or Bleu de Lyons, so prepared presents itself as a reddish powder 
 with a golden lustre, soluble in alcohol or methylated spirits. The solutions 
 can be used for dyeing or printing. According to M. Willm, azuline is com- 
 posed of C 24 H I2 N0 4 , which, in his opinion, may be considered as dioxy- 
 
 phenylamide, or — 
 
 (C I2 H 5 2 
 
 N C I2 H 5 2 
 
 I H 2 
 
 As regards the dark blue aniline colours resembling indigo, M. Fritzsche 
 
 observed, during some of his researches on aniline, the production of a dark 
 
 blue substance, which he prepared by mixing together equal volumes of a 
 
ANILINE BLUES. 
 
 197 
 
 solution of a salt of aniline and alcohol, and adding to this another solution 
 containing chlorate of potassa and hydrochloric acid : after a short time a 
 dark indigo-blue precipitate is produced, which, when washed with water, may- 
 be dried and preserved. This colour is not practically available for dyeing, 
 owing to its insolubility. Dr. Hofmann also produced this colour by acting 
 on a solution of hydrochlorate of aniline with a solution of hypochloric acid. 
 Messrs. Clift, Lowe, and Calvert, of Manchester, also produced it by acting 
 on hydrochlorate of aniline with chlorate of potassa. M. Willm has also 
 obtained this peculiar blue by mixing the sesquichloride of iron with nitrate 
 of aniline : after a short time a chemical action sets in, when the liquor 
 becomes purple, from which is gradually deposited the blue colouring matter. 
 The same reaction is obtained by substituting bichromate of potassa for the 
 chloride of iron. According to this same author, this blue is also procured 
 when a salt of aniline is mixed with red prussiate of potassa, but the blue 
 produced in this instance is soluble in alcohol, which is not the case with the 
 other varieties. These blues resist all chemical agents excepting acids, which 
 turn them green. This is the only drawback to their employment as substi- 
 tutes for indigo, but notwithstanding this defect they are applied in calico- 
 printing for producing greens, blues similar to indigo, and blues and greens so 
 dark as to appear black. 
 
 Some of the most important aniline blues are made by phenylation, in a 
 manner similar to what has been already described under aniline violets. 
 The apparatus employed is a retort of enamelled cast-iron, of the capacity of 
 about 20 litres, and heated by means of a paraffin-bath. It is composed of 
 two pieces, the neck and the cylinder, united by means of pressure-screws. 
 To the neck of the retort are adapted a receiver and a cohobator, the latter 
 serving to maintain the same excess of aniline to the conclusion of the 
 process. The retort is fitted with a mechanical agitator, whose axis moves in 
 a tube serving as a passage for a current of steam. (See Fig. 19.) Into 
 this apparatus are introduced — 
 
 Acetate of rosaniline 5 kilos. 
 
 Aniline 13 ,, 
 
 Heat is then applied, and the temperature is kept close upon 170 C, by means 
 of a thermometer plunged in the retort. The operation lasts about two hours, 
 its progress being judged by withdrawing successively small portions with a 
 rod, and dissolving them in alcohol and acetic acid upon a piece of white 
 porcelain. The spot ought to be entirely and purely blue. If there is a too 
 decided red halo round the streak the operation is not complete. If the halo 
 is of a sallow, brown, or greyish-green tint, the process has been carried too 
 far. In a well-managed operation the blue should remain dissolved in the 
 excess of aniline, and when the reaction is over the mass should appear semi- 
 fluid, but perfectly homogeneous. The retort is then raised up by means of 
 pulleys, and the screws which secure its head to the boiler are undone, so that 
 the contents may be poured out. 
 
 The crude mass is treated differently, according to the kind of colour 
 desired. For the common blues, all that is required is the separation of the 
 blue from the excess of aniline. One method for attaining this object consists 
 in sweeping the aniline mechanically away by a current of steam. In the 
 other method it is removed by washing with dilute acids. The residue is then 
 fit for sale. 
 

 ig8 
 
 DYEING AND CALICO PRINTING. 
 
 Refined Blues are obtained by various methods. The crude product is mixed 
 with alcohol, and poured in thin streams into water acidulated with hydro- 
 chloric acid. There is formed a salt of aniline, which remains in solution 
 along with any excess of unconverted rosaniline, and the blue is precipitated. 
 It is then collected on a filter, and repeatedly washed with boiling acidulated 
 water. 
 
 Night blue, so called because it preserves its tone by artificial light, is 
 simply a salt of triphenylic rosaniline, perfectly pure. To prepare it, the 
 refined blue resulting from the last operation is repeatedly washed with cold 
 alcohol, and then dissolved in boiling alcohol, after having been finely 
 
 Fig 
 
 Apparatus for the Preparation of Aniline Blue. 
 a. Retort of enamelled cast-iron, immersed in the oil-bath, b. c. Vertical shaft, 
 carrying two agitators, the one d, a spiral, and the other fitted with wings parallel 
 to the sides of the retort, and with teeth extending very nearly to the bottom. 
 /. Cover fitted on to the retort by the pressure-screws, g, and carrying h, a stuffing- 
 box for the shaft c; another, t, for the thermometer and a tubulure,;', communicating 
 at will by means of cocks with a worm, A, or a verm cohobator, k', and /. a tube for 
 introducing steam into the apparatus. The steam may be otherwise introduceJ by 
 having a hollow shaft for the agitator in place of a solid one. Movement is given 
 by the pullies, m m, and the cog-wheels, n n. 
 powdered. The mixture is then filtered, and mixed with an alcoholic solution 
 of caustic soda, when the blue is entirely thrown down as a base. When the 
 whole is cold the colour is collected on a filter, washed repeatedly with boiling 
 water, and then treated with a sufficient quantity of the acid intended to form 
 
 a salt. 
 
 Another method is to dissolve the refined blue, in a mixture of alcohol and 
 hydrochloric acid, in double-bottomed retorts enamelled within. The mixture 
 is boiled, when a part of the alcohol distils off, and it is then allowed to cool. 
 
ANILINE BLUES. 
 
 199 
 
 As the pure hydrochlorate of triphenylic rosaniline is less soluble than the 
 accompanying impurities, it is dissolved last and re-deposited first, and is 
 separated from the liquid. By repeating this treatment several times the blue 
 can be obtained pure. 
 
 The mother-liquors are carefully collected, and distilled over lime. Alcohol 
 passes over first, then aniline, whilst the colouring matters remain along with 
 the lime. We shall still briefly describe some of the procedures used to obtain 
 the shades of blue known in commerce as B., B.B., B.B.B., &c. 
 
 The first of these shades is produced by heating, in the apparatus Fig. ig, 
 the subjoined mixture, to the temperature of 180 C, for about two hours : — 
 
 2 kilos, pure rosaniline ; 
 
 3 kilos, pure aniline, distilling at 182* to 185°, and free from hydrocarbons. 
 270 grs. crystallisable acetic or benzoic acid. 
 
 The choice of these two acids is not indifferent. Acetic acid furnishes colours 
 better adapted for wool, and benzoic for silk. 
 
 When the colour is found, by the trial method above described, to have 
 reached the proper shade, the retorts are emptied into a wooden vessel con- 
 taining 10 kilos, of concentrated hydrochloric acid, constantly stirring. The 
 whole is then filtered, and the residue pressed, washed in a large amount of 
 water acidulated with hydrochloric acid, and kept at the boiling-point by 
 blowing in steam. This treatment is continued until the blue is quite reduced 
 to a powder. It is then filtered and pressed again. The yield is 3$ kilos, of 
 dry blue. 
 
 The preparation of the shade B.B. is quite similar, but the amount of 
 aniline used is increased from 3 kilos, to 5. To purify the result, the contents 
 of the retort are poured into a vessel of enamelled cast-iron, surrounded by 
 cold water, to stop further reaction. When the product is cooled down to 150 
 add 7 or 8 kilos, of concentrated alcohol, and stir till the whole is perfectly 
 homogeneous. The apparatus is then placed in a water-bath, and heated till 
 the alcohol begins to boil. It is then taken from the water-bath, allowed to 
 cool, and the colour precipitated by adding — with constant stirring — 10 to 12 
 kilos, of hydrochloric acid. The whole is then filtered, always at the same 
 temperature of 45 if constant results are aimed at ; the product is pressed, 
 washed in abundance of water, and dried. The yield is 1 kilo. 325 grms. 
 of B.B. 
 
 To obtain B.B.B., take 1 kilo, of B.B., finely ground and quite dry, 
 
 1 kilo, of alcohol, and 2 kilos, of aniline, and heat the mixture in the water- 
 bath, with continued agitation till the mixture is uniform. The viscid liquid 
 resulting is then poured into 25 kilos, of alcohol, and heated to boiling, when 
 
 2 kilos, of an alcoholic solution of soda are added, containing 20 per cent of 
 alkali. The solution is filtered, precipitated with a slight excess of hydro- 
 chloric acid, allowed to settle for forty-eight hours, filtered, drained, and the 
 residue pressed. The blue obtained is washed with boiling water slightly 
 acidulated, collected, and dried. One kilo, of B.B. yields thus about 800 grms. 
 of B.B.B. 
 
 Soluble Blues. — The aniline blues hitherto described have the inconve- 
 nience of being soluble only in alcohol. The analogy existing between 
 triphenylic rosaniline and indigo sus:f; r:f: ted the use of sulphuric acid. In 1862 
 Nicholson succeeded in obtaining a true sulpho-conjngate acid of triphenylic 
 
SBBBBHRi 
 
 200 DYEING AND CALICO PRINTING. 
 
 rosaniline, analogous to the sulphindigotic. In the preparation of the earlier 
 soluble blues a very large proportion of sulphuric acid was employed. The 
 mixture was — 
 
 Sulphate of triphenylic rosaniline 10 parts. 
 
 Sulphuric acid 40 ,, 
 
 The ingredients are mixed at once, and the reaction accelerated by means of 
 heat. The temperature is raised, by means of a steam-jacket, to 130 or 140* 
 C, but must never pass 150 . When the mass is homogeneous, and when a 
 drop of the acid blue gives a complete and clear solution in ammonia, the 
 rea&ion is over. The mass is allowed to cool, and poured by slow degrees 
 into 8 to 10 times its weight of water, with constant stirring. The blue 
 is thrown down in a state of fine division, which is filtered and washed till the 
 water begins to take a blue colour, showing that the mass is no longer acid, 
 the coupled blue sulpho-acid being insoluble in dilute acids, though soluble in 
 pure water. It is then dried in any convenient manner. When dry it is put 
 in a cast-iron vessel enamelled within, mixed with a slight excess of ammonia, 
 and heated. The coloured salt floats on the surface as a golden-bronzy layer. 
 It is collected, broken up, dried, and powdered, and is now ready for use. 
 The more recent method of preparing soluble blues differs in employing a 
 smaller proportion of sulphuric acid, and in keeping the temperature below 
 ioo° C. One kilo, of B.B. blue is finely powdered, and added by degrees to 
 3 litres of concentrated sulphuric acid, and the mixture is kept at the tem- 
 perature of the water-bath till a drop thrown into water gives a blue precipitate, 
 which is washed by decantation. The precipitate thus purified and freed from 
 acid should not colour water, and should dissolve without residue in aqueous 
 solutions of soda or ammonia. The whole mass is then poured into 30 litres 
 of water, constantly stirring, — an operation performed in wooden vats hooped 
 with wood. The whole is allowed to settle for twenty-four hours, and is filtered 
 through stout flannel. The precipitate, when it ceases to drop, is pressed. 
 The pressed residue is heated in the water-bath with hydrate of soda till all 
 the mass is dissolved. The neutralisation of the soda should be as exadl as 
 possible. The blue is then allowed to dry on enamelled plates, in a hot 
 chamber, powdered, and mixed with 20 per cent of crystalline carbonate of 
 soda. 
 
 Nicholson blue and Guernsey blue are manufactured by Messrs. Brooke, 
 Simpson, and Spiller, and have the advantage of ready solubility in water, 
 combined with a greater degree of fastness than most aniline colours can 
 offer. The exacT: method of their preparation has not been made public. 
 
 In dissolving and dyeing with aniline blues, a variety of processes are 
 employed. The ordinary blues, as we have already intimated, are insoluble in 
 water, and can be brought into solution by the use of alcohol or wood-spirit.* 
 The purer a blue, the more alcohol is required for its solution, and the greater 
 difficulty is experienced in fixing it upon cotton. The common blues are 
 prepared for use by boiling in alcohol sufficient to take them up, and then very 
 carefully straining. They dye wool and silk without mordants, the former at 
 
 * It may be useful to point out a distinction often overlooked. Methylated spirit is common 
 alcohol mixed with a small percentage of wood-spirit, which latter is otherwise known as 
 jnethylic alcohol or wood-naphtha. 
 
ANILINE BLUES. 
 
 high and the latter at a low temperature. Sulphuric acid, or in case of silk 
 tartaric acid, may be added to the dye-bath with advantage. 
 
 The opal blues are still less soluble. They should be ground to a very fine 
 powder, and well rubbed together with sulphuric acid sufficient to moisten the 
 colour. The acid employed should be perfectly free from lead and from nitro- 
 gen compounds. Alcohol is then added, sufficient to dissolve the whole. The 
 mixture is raised to the boiling-point, and maintained at that temperature till 
 all is dissolved. The liquid is then very carefully filtered. 
 
 For cotton these blues have no affinity, and the attempts to fix them upon 
 that fibre in dyeing have not been very successful. In printing they may be 
 fixed by means of albumen or ladtarine, as described under Magenta. The 
 following modification of Perkin's process may be successfully used for blues, 
 as well as for all aniline colours whose colouring principle is a base. Arsenious 
 acid is dissolved in pure glycerine to saturation. To each gallon of the 
 thickened aniline colour from one-eighth to one-fourth part of this solution is 
 added, together with an equivalent amount of acetate of alumina. The colour 
 is then printed upon calico, bleached as for madder, and steamed at a pressure of 
 about i lb. per square inch for some three-quarters of an hour. The glycerine 
 is thus dissipated, and an insoluble compound of arsenite of alumina and of 
 the coloured base is produced in the fibre of the cloth. After steaming, the 
 colours are not, as a rule, very bright, but may be rendered so by treatment 
 with boiling soap-lye for half an hour. It seems probable that in this soaping 
 a portion of the arsenite of alumina is decomposed, with the production of a 
 corresponding amount of stearate or oleate — the stearates and oleates of the 
 aniline bases, and their double salts ; but no direct use seems as yet to have 
 been made of them in dyeing cotton, if we may except the following process, 
 which finds a limited application in skein-dyeing. The cotton skeins are first 
 dipped or worked in a solution of alum, and after being well squeezed out or 
 dried they are worked in a bath of soap-lyes. They then take up aniline 
 colours with great facility, but the combination between the fibre and colouring 
 matter is not very stable so far as washing in soap is concerned, though the 
 colours resist light fairly. 
 
 In dyeing piece-goods made of a mixture of animal and vegetable fibre, — 
 such as delaines, coburgs, &c, — the worsted is first made to take an aniline 
 blue in the ordinary manner. The cotton-warp is then dyed a very bright 
 Prussian blue, with " blue-iron " (see chapter on Mordants) and ferrocyanide 
 of potassium. Several mordants have been tried for fixing the aniline blue 
 upon the cotton. Amongst others, the nitrate of sesquioxide of chrome 
 enables the aniline blues to lay a firm hold upon the cotton, but unfortunately 
 at the same time it injures the brightness and purity of the colour already 
 deposited upon the wool or worsted, turning it do a dull purple or slate. 
 
 The Nicholson and Guernsey blues are dyed as follows : — For woollen 
 piece-goods the bath is made alkaline with soda, borax, or silicate of potash. 
 The colour is then added very gradually. The goods are entered at about 
 i2o° F., and worked up slowly to just below the boiling-point, at which the 
 bath is kept for twenty minutes or half an hour, according to the shade 
 required. The cloth is then taken out, washed well in cold water, and worked 
 in a bath slightly acidulated with sulphuric acid, in order to develope the 
 colour. The pieces are finally washed in cold water. In order to ascertain 
 

 202 DYEING AND CALICO PRINTING. 
 
 whether the required shade has been reached, several bits of waste material 
 of a similar kind are tacked on to the goods being dyed. From time to time 
 one of these is taken off, rinsed in water, steeped for a moment in dilute acid 
 in order to try the shade. The accompanying specimen of Nicholson's 
 blue (4 B) we owe to the courtesy of the firm of Brooke, Simpson, and 
 Spiller. 
 
 Guernsey blue is a very permanent colour, and is frequently applied upon a 
 ground of cam-wood or santal-wood, in order to produce a cheap and perma- 
 nent shade resembling a vat-blue. 
 
 ANILINE GREENS. 
 Usebe Green, Cherpin Green, Emeraldine, Night Green, Rosaline Green, 
 Emerald-Green, Aldehyde Green, Iodine Green, Ethyl-rosanilinc Green, 
 Picrate of Ethyl-rosanilinc, Sexcthyl-rosaniline, Iodide of Ethyl Green, 
 Pomona Green, &c. 
 The earliest aniline green introduced was the emeraldine of Messrs. Lowe, 
 Clift, and Calvert, which was not prepared as a separate dye, but produced on 
 the fibre. To print with this colour, 500 grms. of chlorate of potash were 
 dissolved, with the aid of heat, in 25 to 30 grms. of starch liquor. When the 
 mixture was cool, 1$ kilos, of the acid chloride of aniline (or of one of its 
 homologues), containing 500 grms. of aniline, was carefully incorporated. The 
 colour was developed by exposing the printed goods to the air for twelve to 
 eighteen hours. The process has now merely a historical interest. 
 
 Iodine Green, or Bimethyl-Iodhydrate of Trimethylic Rosaniline. 
 This is obtained, in greater or less quantity, in the preparation of Hofmann's 
 violet. Tillmanns, Meister Lucius, and Bruning, all made more or less suc- 
 cessful attempts at its manufacture in 1865. In the same year Wanklyn 
 patented a process for its production, which became the starting-point for the 
 present successful methods. 
 
 It is now manufactured in air-tight vessels of enamelled iron, of the capacity 
 of 80 to 100 litres, and capable of bearing a pressure of 25 atmospheres. 
 They are heated by means of a steam-jacket (Fig. 20). As the green 
 begins to decompose at no C, it is necessary to know exactly the tempera- 
 ture of the steam circulating in the steam-jacket, which is therefore fitted 
 with a pressure-gauge. In the head of the vessel is adapted another, to indi- 
 cate the pressure existing in the interior of the apparatus. There is also a 
 screw-tap, by which, at any given moment, the excess of the reagents 
 employed, or of the liquid products of the reaction, may be distilied off. The 
 ingredients used are — 
 
 10 kilos, of pure acetate of rosaniline; 
 
 20 ,, pure iodide of methyl; 
 
 20 ,, methylic alcohol, boiling at 64 to 70° C. 
 
 Steam is now turned on, taking care that during the whole operation the 
 pressure in the steam-jacket may not exceed 1 atmosphere. In the interior of 
 the boiler the pressure rises rapidly to 8 atmospheres, and then more gradually 
 to 10 or 11, which it must not be allowed to exceed. The process lasts four 
 to five hours. At the expiration of that time the steam is turned off, and the 
 apparatus allowed to cool. The pressure falls by degrees, and after twelve 
 
ANILINE GREENS. 
 
 203 
 
 Nicholson's Blue (4 B.) 
 
 hours it still amounts to 4 atmospheres. A tube is then fixed to the screw- 
 tap, which leads to a worm, communicating with a series of large globes, and 
 the distillation is begun. 
 
 When the distillation is at an end the boiler is opened, and the semi-fluid 
 contents are drawn out, and put to dissolve in a boiler containing 600 litres of 
 distilled water and fitted with a steam-jacket. The green dissolves entirely, 
 whilst the violet matters remain insoluble, with the exception of a small 
 quantity which is kept in solution by the acid set free during the readtion. 
 This residue is removed by a first filtration. To the filtrate about 35 kilos, of 
 common salt are added ; the boiling is continued, and the free acid is 
 neutralised by crystalline carbonate of soda. To regulate the quantity, a 
 
 Saffranine Pink. 
 
204 
 
 DYEING AND CALICO PRINTING. 
 
 small portion of the liquid is taken and filtered over sand. When the filtrate 
 runs through a fine green, without any mixture of hlue or violet, the addition 
 of carbonate of soda ceases, ij to if kilos, of crystals being generally suffi- 
 cient. The whole liquid, when cold, is now filtered over sand, to remove blue 
 and violet matters. The filtrate is precipitated by a cold saturated solution of 
 perfectly pure picric acid. For the proportions taken, 3'46 kilos, of picric acid 
 will be required. The picrate formed is but sparingly soluble in water, and is 
 consequently thrown upon a common filter and slightly washed. The preci- 
 pitate is a very fine paste. It is allowed to drain till sufficiently concentrated. 
 The dyer is obliged to make use of a small proportion of alcohol in dissolving 
 this green. 
 
 Soluble Green. 
 In preparing this colour we substitute for the picric acid the sulphate, chloride, 
 or acetate of zinc ; there are thus obtained double salts of zinc, and of the 
 
 Fig. 20. 
 
 a ft. Boiler and lid. c. Bath, containing water heated by steam circulating in the 
 worm, d. An oscillatory movement on the trunnions, e, is given to the boiler by 
 the excentiic,/, the crank, g, and the handle, h. This oscillatory movement may be 
 replaced by an internal agitation of the contents by means of the pulley, /, the 
 shaft, k, and the paddles, m. 
 
 dimethyl-hydriodate of trimethyl-rosaniline. These compounds are soluble in 
 water, and of a less yellow tone than the picrate. They are sold in the dry 
 state. 
 
 The yield of the process should be about 60 per cent of green and 40 of 
 violet, which can be transformed into green as follows : — The violet is well 
 washed with water, dried, and powdered. It is then dissolved in pure alcohol 
 (free from methylic spirit), and its base is liberated by the addition of 
 caustic soda. It is then put in a suitable apparatus, provided with an agitator 
 and a cohobator. An equivalent weight of methylic iodide is added, and the 
 apparatus is carefully heated in the water-bath, so as not to exceed 48° C. As 
 soon as the conversion is over, which is very rapid, the whole is quickly cooled, 
 acetic acid is added, and the contents are poured into a large wooden vat 
 containing hot water. The green is separated from residual traces of violet 
 
ANILINE GREENS. 
 
 205 
 
 by means of common salt and soda crystals ; the filtrate is precipitated with 
 common salt, and the precipitate collected and dried. The green prepared in 
 this manner is generally finer than that made direclly from rosaniline. 
 
 Crystalline Green. 
 To obtain the green in a pure crystalline state the crude product is poured 
 into a very small quantity of boiling water, — about 60 litres for an operation 
 made with 5 kilos, of acetate of rosaniline. In separating the green from the 
 violet, soda crystals are used more freely, even at the risk of destroying a part 
 of the green. The boiling filtrate, on cooling, deposits fine green needles on 
 the copper rods suspended in the crystallising vat, whilst a crust of less pure 
 crystals settles at the bottom. These crystals are washed slightly with water 
 and dried. 
 
 Aldehyde Green. 
 
 This colour was discovered by Cherpin in 1862. Its chemical constitution 
 is still unknown. Hofmann's analysis shows it to consist of C 2 aH 27 N3S 2 0. 
 For its preparation 1 kilo, of rosaniline is dissolved in 2 kilos, of sulphuric 
 acid, of sp. gr. 1-63, previously mixed with 500 grms. of water. When the 
 solution is homogeneous, it is mixed with 4 kilos, of a concentrated alcoholic 
 solution of aldehyde, added in successive portions. The reaction is complete 
 in about twenty minutes. The mixture is poured into 25 litres of water, in 
 which 4 kilos, of hyposulphite of soda have been previously dissolved. The 
 liquid is boiled seven or eight minutes, and filtered. The green is found in 
 solution, and is thrown down by means of tannin, acetate of soda, or a salt of 
 zinc along with an alkali. The green is washed with water to remove organic 
 salts, re-dissolved in alcohol, and precipitated with ether. This green yields 
 beautiful shades in dyeing and printing, but is always prepared by the con- 
 sumer when wanted, as it spoils on keeping. 
 
 In dyeing with greens sold as insoluble tannates, it is necessary to dissolve 
 in water acidulated with sulphuric acid. In this solution wool and silk are 
 dyed, the former at a higher temperature than the latter. 
 
 On wool very full shades may be obtained with iodine green by the following 
 process recommended by Dale. The wool is simply worked in very dilute 
 hypochlorite of lime (bleaching-lime), and is then found to take up the colour 
 very readily. 
 
 The so-called pomona paste of commerce dissolves freely in water without 
 alcohol. It is worked upon wool as follows : — A bath of warm water is pre- 
 pared at 158 F., to which silicate of potash is added sufficient to give the 
 water a greasy feel. In this the wool or woollen yarn is worked to saturation. 
 The colour, which has been in the meantime separately dissolved in some cold 
 water, is now very gradually added to the above bath, the wool being still 
 worked till a bit taken out — and passed through some water acidulated with 
 acetic acid — shows the right shade. The whole is then taken out and put in 
 a separate bath of water, at 158 F., soured with acetic acid. A little com- 
 mercial tannin or extract of galls may be added to fasten the colour. If the 
 shade is not sufficiently yellow, picric acid is added to the last bath. 
 
 Cotton is first well worked in sumach, galls, or myrobalans ; then in double 
 muriate of tin. It is next rinsed in water, and worked in the colour dissolved 
 in cold water. 
 
mmwfcmfM&mssm ^SHI 
 
 
 206 DYEING AND CALICO PRINTING. 
 
 In printing, Sevez recommends the following process: — 
 
 Solution of gum . . .. .. 1 litre. 
 
 Paste green 250 grms. 
 
 Bisulphite of soda 150 „ 
 
 The mixture is heated in the water-bath to dissolve the salt, and then allowed 
 
 to stand for three or four days. At the end of this time it is used for printing. 
 
 The colour will bear steaming, but the ^result is less satisfactory upon calico 
 
 than upon silk and worsted. 
 
 Rosanaphthylamine, or Naphthylamine Red. 
 
 To prepare this beautiful colour, introduce into a glass flask, capable of 
 holding 10 litres, — 
 
 3 kilos, of azonaphthyldiamine, in powder ; 
 3 ,, naphthylamine, in powder ; 
 
 2J ,, crystalline acetic acid. 
 
 The flask is now heated in the sand-bath until the mixture is completely dis- 
 solved, but care is taken to keep the temperature between 160 and 180° C. 
 The red colouring matter is developed by degrees, and at the same time 
 ammonia is given off. The operator must watch lest the colour should pass 
 on into a violet, and stop the operation as soon as the slightest violet colouration 
 appears. At this instant 150 or 200 grms. of crystaliisable scetic acid are 
 added ; the flask is removed from the sand-bath, and the contents are poured 
 out upon plates of sheet- or cast-iron. The crude matter thus obtained con- 
 tains, besides rosanaphthylamine, acetate of naphthylamine, violet colours, and 
 other secondary products. To purify the rosanaphthylamine, 10 kilos, of the 
 crude matter are treated with 500 litres of water, acidulated with hydrochloric 
 acid. When the solution is complete, and the liquid saturated, it is carefully 
 filtered through woollen cloth. The filtrate is exactly neutralised with carbonate 
 of soda, and mixed with common salt in excess. Hydrochlorate of rosa- 
 naphthylamine is thrown down in a crystallised state. The crystals are 
 purified by two or three successive solutions in rcidulated water and precipi- 
 tations with common salt, and are then sufficiently pure for dyeing. 
 
 The colour produces bright rose shades, with a peculiar reflection which 
 renders it valuable for dyeing silks and velvets. 
 
 Geranosine. 
 
 This beautiful ponceau red, first prepared by Luthringer, is a product of the 
 oxidation of rosaniline, and is possibly one of the stages of transition from 
 rosaniline to rosolic acid. 
 
 For its preparation 1 kilo, of any salt of rosaniline is dissolved in 1000 litres 
 of boiling water, and the solution is allowed to cool down to 45 C. 
 
 On the other hand, 4$ kilos, of the nitrite of barium or calcium, or of per- 
 oxide of barium or calcium, are dissolved in 35 litres of cold water. The 
 two liquids are then mixed, and 10 kilos, of the strongest sulphuric aiid are 
 added. The solution becomes at once a lemon-yellow, and after a few 
 moments it is quite colourless. The sulphate of baryta precipitated is filtered 
 off, and the temperature of the mixture is progressively raised to 100°. By 
 degrees the liquid begins to assume an intense red, and after boiling for two 
 
ANILINE BROWNS. 
 
 207 
 
 minutes the reaction is complete. The liquid, when cold, is mixed with 
 chloride of sodium, and the geranosine precipitated is collected on filters. 
 The colour is soluble in water, and especially in alcohol. It is not decolourised 
 by ammonia. Acids make the shades brighter. 
 
 Saffranine. 
 
 This is a colouring matter of a bright red rose, resembling carthamine. It 
 is produced by the action of nitrites upon heavy anilines : 2 parts of baraniline 
 are heated for five or six minutes to 8o° to ioo° C, with 1 part of arsenic acid 
 and 1 part of a metallic nitrite, when a coloured mass is obtained which is 
 treated with boiling water. The solution is neutralised with an alkali. The 
 intensely red liquid is filtered, and precipitated with common salt. The pre- 
 cipitate, filtered and drained, is sold as a paste. Saffranine is also producible 
 by the action of chromic acid. 
 
 The shade of specimen is produced by mixing 1 gill of saffranine paste with 
 20 gills of the subjoined thickening: — 1 gallon of acetate of alumina standard, 
 1 gallon of water, 2 lbs. of starch. Boil, cool, and add 1 pint of arsenic and 
 glycerine standard. 
 
 The " Acetate of Alumina Standard " is made with : — 1 gallon of boiling 
 water, 2J lbs. of alum. Dissolve, and add 3 lbs. of white acetate of lead. 
 Dissolve, let settle, and use the clear liquid. 
 
 The "Arsenic and Glycerine Standard": — 1 gallon glycerine, 4 lbs. 
 arsenious acid. Boil till dissolved, and filter. 
 
 After the saffranine colour has been printed on the goods are steamed for 
 thirty minutes. 
 
 Phcenicine. 
 
 This is another fine red colouring matter, discovered by Willm in 1861, and 
 prepared by boiling an acetic solution of mauveine with binoxide of barium. 
 The ponceau shade is quickly developed. The boiling is then stopped, and 
 the excess of acetic acid is exactly neutralised with a standard solution of 
 carbonate of soda. Carbonate of baryta is added, the mixture is filtered, and 
 phcenicine remains in the filtrate. It may be thrown down by the addition of 
 common salt. 
 
 Phcenicine may be analogous to the geranosine of Luthringer. It may 
 possibly be identical with the ponceau colour described by Delvaux. He 
 dissolves 1 part of chromic acid in 18 to 20 parts of water, and adds 1 part of 
 aniline. After standing for some hours a blackish precipitate is formed, which 
 is filtered off, while the liquid retains a yellowish-brown colour. The preci- 
 pitate on treatment with boiling water yields a liquid which dyes silk or wool 
 of a reddish-violet. If rendered alkaline with ammonia the violet colour is 
 thrown down, and the red or ponceau remains in solution. 
 
 ANILINE BROWNS. 
 A maroon-brown was patented by Girard and De Laire in 1863 : they take 
 4 parts by weight of anhydrous hydrochlorate of aniline, and 1 part of dry 
 magenta (not an acetate), which is put in as soon as the hydrochlorate melts. 
 When the magenta is perfectly dissolved the heat is raised to 240 C, and 
 maintained until the colour — which was at first of a reddish violet — suddenly 
 becomes a maroon. The process lasts one hour or two, and its approaching 
 

 208 
 
 DYEING AND CALICO PRINTING. 
 
 termination is known by the appearance of yellow fumes, which condense in 
 the cold parts of the apparatus, whilst an alliaceous odour becomes re- 
 cognisable. The maroon-brown matter thus obtained is soluble in water, 
 alcohol, and acids. The aqueous solution is employed at once in dyeing, 
 without preliminary treatment. It may, if required, be purified by precipita- 
 tion with common salt. The so-called naphtha-brown is merely the crude 
 melt from the manufacture of magenta, containing consequently the secondary 
 products and undecomposed aniline. Sieberg prepares a brown from the 
 colouring matters precipitated from the mother-liquors resulting from the 
 manufacture of magenta. He heats i part of hydrochlorate of aniline up to 
 the point of fusion, and adds then J part of the colouring matter just men- 
 tioned, the apparatus being set in a sand-bath until the brown colour is deve- 
 loped. The product is mixed with 2 parts of carbonate of soda crystals and 
 25 litres of hot water, and is well stirred and mixed up. The solution is then 
 decanted, and the brown is repeatedly washed with water. In this state it 
 presents the appearance of a brownish-black tarry mass : 5 kilos, of this crude 
 mass are dissolved in 45 litres of alcohol ; 65 litres of water are added, with 
 constant stirring. The clear liquid, after settling, is ready for use. 
 
 Another brown colour is met with in commerce, obtained by causing metallic 
 tin and hydrochloric acid to react upon binitro-benzine, and treating the 
 resulting mass with an alkaline or metallic nitrite. 
 
 Schultz prepares a garnet-brown by causing hyponitric acid to react upon a 
 salt of rosaniline. A variety of brown matters may be obtained by oxidising 
 rosaniline or leukaniline by means of chlorate of potassa, peroxide of lead, 
 bichromate of potassa, &c. 
 
 Jacobsen's brown is made by introducing into a capacious flask 1 part of 
 picric acid and 2 parts of commercial aniline. The mixture heats, and the 
 . picric acid dissolves to a thick liquid of an orange-yellow, a result which is 
 promoted by stirring and the application of a gentle heat. When the tem- 
 perature is raised to no° to 120 the mass grows brown, and throws off 
 abundant vapours. To avoid boiling over, the temperature is kept at 140 , or 
 at the utmost not above 160 C, for some hours, as long as ammoniacal fumes 
 are given off. The process is at an end when a small portion taken out of the 
 flask and thrown into water gives only a very feeble yellow tint to the liquid. 
 The black mass is then poured, with constant stirring, into water strongly 
 acidulated with hydrochloric acid, and boiled repeatedly in successive portions 
 of water to remove any undecomposed aniline. It is still better to grind up 
 the mass before allowing it to boil, and again after the liquid has rooled ; to 
 facilitate the removal of a red colouring matter. The residue, after boiling, is 
 collected upon a filter, and well washed, first in a dilute solution of soda, and 
 then in pure water. If the temperature has not been raised too high, the mass 
 is entirely soluble in alcohol. For use it is dissolved in alcohol, acidulated 
 with sulphuric acid and mixed with glycerine. It dyes silk and wool without 
 mordant, the former a Corinth red, and the latter a black-brown with a violet 
 reflection. 
 
 The crude colour may also be purified by adding it to concentrated sul- 
 phuric acid. After some time the sulphuric solution is poured into water, 
 and the pure colour is precipitated by the addition of common salt. In this 
 state it is more readily soluble in alcohol. 
 
ANILINE YELLOWS AND ORANGES. 209 
 
 The aniline browns are generally dissolved in boiling water, and used 
 diredly for dyeing. In case of wool and ssilk no mordant is required. Upon 
 cotton they are fixed by processes similar to those already indicated for other 
 aniline colours. The shades produced caui be modified at discretion by the 
 addition of acids to the dye-bath, or of maigenta in larger or smaller amount. 
 
 In printing, a garnet-brown may be produced upon the fibre by the following 
 process, due to Kcechlin : — 
 
 Solution of magenta, 50 grms. to a litre of alcohol . . 25 centilitres. 
 
 Gum-water 75 „ 
 
 Oxalic acid 50 grms. 
 
 Chlorate of potassa 25 ,, 
 
 By adding successively increasing doses of neutral extract of indigo, the 
 shade may be modified up to a black. If ai redder garnet is required the pro- 
 portions of oxalic acid and of chlorate of p>otassa should be diminished. For 
 a yellower shade any yellow lake may be added to the colour, provided it does 
 not contain oxide of tin for its base. 
 
 ANILINE YELLOWS AND ORANGES. 
 
 Chrysaniline, or phosphine, was discovered by Nicholson, and is manufac- 
 tured by the firm of Brooke, Simpson, and Spiller. Their process is kept 
 secret, but the following method is given by Girard and De Laire : — 1000 kilos, 
 of the crude residue from the manufacture of roseine are dissolved in 12,500 
 litres of boiling water, to which 85 kilos., of hydrochloric acid have been 
 added. Violanilinc remains insoluble. The boiling solution is filtered, and to 
 the filtrate 125 kilos, of hydrochloric acid ane added. On cooling, a precipitate 
 (A) is formed, consisting of about 40 to 45 kiilos. of hydrochlorate of rosaniline, 
 mixed with a little rosaniline and resinous matters. 
 
 The filtrate is treated with 625 kilos, of common salt. The precipitate, 30 
 to 35 kilos., is a mixture of mauvaniline andl salts of rosaniline. Name it A. 
 The mother-liquor, filtered off, is saturated with 83 kilos, of soda-ash, con- 
 taining 58 - 64 per cent of actual soda. The product, B, 205 to 210 kilos., 
 consists almost entirely of salts of rosanili ne, and a very small quantity of 
 salts of chrysotoluidine. 
 
 To the filtrate 37 kilos. 500 grms. of soda-ash are added, when a precipitate 
 is formed, 37 to 40 kilos., consisting of chrysotoluidine, with a small trace of 
 rosaniline : 100 kilos, of this last precipitate are dissolved in 2500 litres of 
 lime-water, containing a little lime in suspension. After boiling, the whole is 
 filtered, and the filtrate colleded in a crystal. lising-vat containing hydrochloric 
 ncid. On cooling a salt of rosaniline is obta.ined, containing a trace of chryso- 
 toluidine, and known as yellow magenta. T he insoluble residue contains the 
 yellow colour. To remove the lime it is heated in a vessel of enamelled cast- 
 iron, along with a very little water and hydrochloric acid, just sufficient to 
 saturate the lime. The chrysotoluidine melts, floats on the surface, and is 
 removed with a skimmer and washed a time <or two in a little cold water. To 
 remove the last traces of rosaniline 100 kilos . of the skimmings are dissolved 
 in 2000 litres of boiling water, with 100 kilos, of hydrochloric acid. When 
 the solution is made 10 kilos, of zinc are added, and the whole is kept at the 
 boil for eight hours. It is cooled, filtered, and precipitated with 20 kilos, of 
 common salt, the acid being almost entirelly neutralised by the addition of 
 
 p 
 
210 DYEING AND CALICO PRINTING. 
 
 carbonate of soda. The yield is 80 kilos, of amorphous chrysotoluidine. 
 This is anew dissolved in 2000 litres of boiling water slightly acidulated, the 
 solution is filtered, and precipitated with 50 kilos, of caustic soda at 12 B. 
 The precipitate is collected, washed with cold water, and dried. It is treated 
 with 8 kilos, of sulphuric acid, then with 200 litres of hot water, and kept at 
 a boil for two hours. The solution, when cooled, is precipitated with great 
 care by carbonate of soda, yielding 20 kilos, of a yellowish-maroon matter. 
 The filtrate, containing chrysotoluidine nearly pure, is precipitated with 
 common salt, and yields about 25 kilos. These two substances are then 
 pressed separately, and each is treated with the amount of sulphuric acid 
 required to form a sulphate : 100 kilos, of the original crude matter, " C," 
 yield 20 kilos, of the yellow-maroon matter, suitable for dyeing skins, and 
 25 kilos, of chrysotoluidine. The formula originally assigned to chrysaniline 
 by Hofmann, who discovered it among the residues of the manufacture of 
 roseine, was C2oH I7 N 3 , corresponding to the percentage composition — 
 
 C 80-26 
 
 H 568 
 
 N 14*04 
 
 Girard and Chapoteaut discovered chrysotoluidine when studying the action 
 of dehydrogenating bodies upon crystalline toluidine. Its formula is C 2I H 2 iN 3 ; 
 and its composition — 
 
 C 8o-oo 
 
 H 6G6 
 
 N i3"33 
 
 The two bases are isomeric, if not identical. Ch-ysotoluidine forms well- 
 defined salts with the acids. 
 
 Scheurer-Kestner obtained a yellow by dissolving mauveine in hydrochloric 
 acid, and adding tin to the liquid. When all is dissolved common salt is 
 added, by which a yellow matter is thrown down resembling chromate of lead. 
 This matter, collected, drained, and pressed, is exhausted with alcohol, in 
 order to separate the colour from the compound of tin. It dyes wool and silk 
 of a yellowish orange. 
 
 Aniline Orange. 
 
 In the mother-liquors obtained in the purification of magenta made by the 
 nitrate of mercury process there is found an orange colouring matter, which is 
 separated by precipitating the accompanying substances with common salt. 
 The orange remains in the solution, and is obtained pure by evaporating and 
 washing the residue. It is readily soluble in alcohol, sparingly in hot water, 
 and scarcely soluble in cold water. It dyes silk and wool a beautiful golden- 
 yellow. 
 
 Zinaline, C 20 H I9 N 2 03, was discovered by Vogel on treating a solution of 
 rosaniline with gaseous nitrous acid. It is insoluble in cold and sparingly 
 soluble in hot water. In alcohol, ether, and chloroform it dissolves readily. 
 It is soluble in acids with a yellow, and in alkaline liquids with a blue colour. 
 It dyes silk and wool a yellow-orange, which can be shaded into red by means 
 of ammonia. 
 
 ANILINE GREYS. 
 
 Castelhaz prepares an aniline grey by dissolving 10 kilos, of mauveine paste j 
 in 11 kilos, of concentrated sulphuric acid, at 66° B. When it is completely 1 
 
ANILINE BLACK. 211 
 
 dissolved 6 kilos, of aldehyde are added, and the mixture is allowed to stand 
 for four or five hours. At the expiration of this time it is poured into water. 
 The grey colouring matter dissolves, and the solution, previously filtered, is 
 precipitated with common salt. These solutions and precipitations are re- 
 peated until the product is sufficiently pure. This preparation dyes a fine grey 
 upon linen and cotton, but its price is hitherto very high. 
 
 Carvis and Thirault prepare a grey (mureine) by dissolving bichromate of 
 potassa and a salt of iron in dilute sulphuric acid, and allowing the mixture to 
 read upon a bi-salt of aniline, preferably the hydrochlorate. 
 
 By varying the respective proportions of the bichromate, of the iron salt, 
 and of the salt of aniline, or by employing other acid salts of the latter, greys 
 may be obtained of a reddish or bluish tone, all which, according to the 
 patentees, are soluble in boiling water, and resist acids and soap better than 
 greys produced by other methods. 
 
 ANILINE BLACK. 
 
 This differs remarkably from the rest of the aniline colours. It is not a 
 definite chemical compound, but a mixture of at least two distinct colours, — 
 the one an intense blue, bordering upon black, and the other a very deep 
 brown. It is produced by the action of powerful oxidising agents upon a 
 mixture of aniline and toluidine. 
 
 This colour is completely insoluble in water, alcohol, ether, benzol, boiling 
 soap-lyes, acids, and alkalies. It has a full, rich, velvety shade, which is 
 turned to a green by acids and restored to its original shade by alkalies. 
 Dilute bichromate of potash increases the intensity of the shade, but, if con- 
 centrated, turns it to a reddish hue. Chlorine and the alkaline hypochlorites 
 destroy it in course of time. But if the action has not been sufficiently pro- 
 longed for the total destruction of the black, but has merely turned it to a 
 garnet-red shade, the original black gradually returns on exposure to the air, 
 and finally regains its former intensity. 
 
 Aniline black has a more powerful affinity for vegetable than for animal 
 fibres. Whether all the various processes for the preparation of aniline black 
 yield products chemically identical is open to question. That it cannot, as 
 maintained by some authorities, consist of mere mixtures of ordinary aniline 
 colours, is proved both by its feebler affinity for wool and silk, and by its inso- 
 lubility in the usual solvents. Some aniline blacks resist more or less the 
 action of light and of chemical reagents, whilst others turn green more or less 
 readily in contact with air containing acid or sulphurous fumes. The more 
 intense an aniline black, the better it resists these agencies. A black deve- 
 loped in presence of excess of aniline is always more stable than one equally 
 concentrated developed in presence of an excess of acid. Hence the latter 
 class of blacks are unsafe. The tissue is weakened, the black obtained easily 
 turns green, and will not bear bleaching liquor. If the gas used in a ware- 
 house where goods dyed or printed an aniline black are stored should contain 
 a little sulphur, the folds of all the pieces may be turned greenish by the sul- 
 phurous acid. When a colour is formed containing excess of base the black 
 will be less likely to turn green, and is better able to bear the action of 
 bleaching liquor. In order that such a black may satisfy all practical condi- 
 tions, it must be developed with sufficient rapidity to avoid the volatilisation 
 
 p 2 
 

 
 
 212 DYEING AND CALICO PRINTING. 
 
 of the aniline, an object easily attained by using chlorate of aniline instead of 
 chlorate of potash. 
 
 Aniline black may be considered as the result of two totally different re- 
 actions : — (i). Decomposition of the chlorate of aniline. (2). Oxidation of the 
 aniline salt which is mixed up with the chlorated salt. By the decomposition 
 of the chlorate of aniline, chlorinated produces of aniline arise. Many degrees 
 of substitution may be thus formed which would explain the difference of the 
 results. Besides these chlorinated products, which form only a portion of the 
 aniline black, another product is formed, the result of the oxidation of the 
 aniline salt. 
 
 Aniline black, commonly so called, consists of two blacks: the one formed 
 by the chlorinated substitutions of aniline is very stable, and resists almost 
 all chemical reagents. Its tone, however, is not so fine as that produced by 
 the admixture of the second product, formed by the oxidation of the aniline 
 salt. This second has an intense violet-blue colour, which when sufficiently 
 concentrated is black. It is much less stable than the other, as it turns green 
 with a trace of free acid, though it resists soaping. The two blacks, the brown 
 and the blue shade combined, form the ordinary aniline black. 
 
 The earliest aniline black was printed on calico by the late Mr. John Light- 
 foot, of Broad Oak Print-Works, Accrington, as early as July, i860. His 
 colour mixture was — 
 
 Starch-paste (ij lbs. per gallon) 1 gallon. 
 
 Chlorate of potash . . 4 ozs. 
 
 j Aniline 8 „ 
 
 I Hydrochloric acid (32 Tw.) 8 ,, 
 
 Sal-ammoniac 4 ,, 
 
 Nitrate of copper (88° Tw.) 2 ,, 
 
 The colour was printed with madder-pink ground, aged two nights ; then the 
 black and pink passed through " Higgins's " alkaline arseniate of soda, mixed 
 with water at 180 F., washed, dunged, dyed in madder, and soaped. 
 
 In 1863 this process was patented, with certain modifications. He describes 
 his method thus : — " I take 1 gallon of water, and dissolve in it 4 ozs. chlorate 
 of potash ; to this I add aniline, or any analogous, homologous, or isomeric 
 matter, using by preference aniline, in the proportion of 8 ozs., previously 
 combining it with 8 ozs. of hydrochloric acid at 32 Tw. After stirring well, 
 I add 1 pint of acetic acid and 8 ozs. measure of perchloride of copper at 88° 
 Tw. ; then I add 4 ozs. sal-ammoniac, or an equivalent quantity of other 
 suitable alkaline chloride. I steep the fabric or yarn in this solution, wring 
 out to dry, then I expose the goods in a room at from 6o° to 70 F. for two or 
 three days ; the goods are now passed through water alone, or a solution con- 
 taining alkaline or metallic salts, which develope the black much sooner and 
 better. The alkalies and alkaline earths may be used for raising the black, 
 such as caustic soda, potash or ammonia, or lime-water; or the goods may be 
 passed, after printing and dyeing, through a box containing rollers supplied 
 with ammoniacal gas (which I prefer when the black is printed along with 
 steam colours, prior to steaming the goods). When the black is printed along 
 with madder or garancine colours they are aged, at from 6o° to 70 F., for 
 three days, and dunged, dyed, washed, and passed through a solution of soap 
 or dilute bleaching-lime, whereby an intense black is produced." 
 
ANILINE BLACK. 213 
 
 This process was very successful in block-printing, and came into use to a 
 great extent, especially in Switzerland. For roller-printing it was less 
 adapted, as the acid chloride attacked both the copper rollers and the steel 
 doctors. These defects were partially remedied by using a neutral chloride of 
 aniline, substituting sulphate of copper for the chloride. It is still employed 
 in hand printing and dead-roller work. 
 
 Lauth's improvement, patented in England by Hughes, substitutes sulphide 
 of copper for either the chloride or sulphate ; his proportions being — 16 ozs. 
 salt of aniline, 4 ozs. sulphide of copper, and 4 ozs. chromate of potash. 
 
 The sulphide of copper for this purpose is prepared as follows : — Flowers of 
 sulphur are dissolved in caustic soda ; the liquor obtained is poured into a 
 solution of sulphate of copper, at the temperature of 75 C. The precipitated 
 copper sulphide is collected upon a filter, and washed. 
 
 Kcechlin proposes the following formula : — Boil together — 
 
 Water 10 litres. 
 
 Starch 2 kilos. 
 
 Torrefied starch 2 „ 
 
 Aniline 2 ,, 
 
 Sal-ammoniac 4 n 
 
 Chlorate of potash 1 kilo. 
 
 When it is to be used, add cold — 
 
 Sulphide of copper paste 1 kilo. 
 
 Tartaric acid 2 kilos. 
 
 The following processes have been found useful in practice : — 
 Dissolve 300 grms. starch in 2 litres of water, 150 grms. tragacanth in 
 another 2 litres, and 750 grms. of light burnt or torrefied starch in a third 
 2 litres. Mix together equal weights of these three solutions, and add with 
 heat the s ' c th or T ' D th part of the weight of this solution of chlorate of potash; 
 let it cool, and add twice as much muriate of aniline as was used of chlorate 
 of potash. If the colour is required for printing, sulphide of copper is added 
 in the same quantity as chlorate of potash. 
 The appended recipe has done good service : — 
 5 kilos, of starch solution ; 
 5 ,, light burnt starch solution ; 
 
 5 ,, tragacanth solution ; 
 
 I kilo, chlorate of potash ; 
 1 ,, muriate of aniline ; 
 And in the application i kilo, of sulphide of copper. 
 Spirk boils together 1 litre of starch-paste (made by dissolving 150 grms. of 
 starch in 1 litre of water) with 1 litre of gum solution (71 grms. of tragacanth 
 to 1 litre of water) and 1 litre of gum substitute solution (42 grms. of dextrine 
 to 1 litre of water. He then adds to the hot mass go grms. chlorate of potash 
 and 75 grms. of sal-ammoniac. The mixture is allowed to stand till cold, 
 when 240 grms. of chloride of aniline are dissolved in it, and 75 grms. of 
 sulphide of copper are added just before printing. 
 
 For a deep body colour the same author recommends the following : — Boil 
 together, for fifteen minutes, 6 litres of water, 1000 grms. of aniline oil, 625 
 of chlorate of potash, and 625 of sal-ammoniac. When nearly cold add to it, 
 
2H DYEING AND CALICO PRINTING. 
 
 with constant stirring, iooo grms. of tartaric acid dissolved in i litre of water. 
 To prepare this colour for printing, boil i litre of this mixture filtered, 
 with 135 grms. of starch and the same weight of dextrine, and just before 
 printing add 60 grms. sulphide of copper. Spirk ages for twenty-four to 
 forty-eight hours, at the temperature of 25 to 30 C. The pieces are then 
 passed through an alkaline bath at 75° C, and lastly through a soap bath at 
 75 to 8o° C. If the white grounds appear dull they are passed through weak 
 bleaching-liquor. In the preparation of aniline blacks H°.rtmann recommends 
 the selection of anilines whose boiling-points lie between 180 to 185° C, and 
 rejects as useless all samples boiling above 192 C, as giving dirty browns or 
 other useless colours. 
 
 The best methods of dyeing aniline blacks have also been investigated by 
 Persoz, whose results may be instructive. Some time age the attempt was 
 made to dye cottons black by passing them through a solution of an aniline 
 salt mixed with bichromate of potash. If the solutions were strong, the 
 colour appeared as soon as the goods left the bath, and speedily became fully 
 developed. A serious difficulty, however, was encountered. If the liquids 
 were dilute no black was produced, and if concentrated the colour was preci- 
 pitated in the bath. It was attempted to obviate this difficulty by cooling the 
 solutions down to near the freezing-point. This was no improvement, as the 
 chromate of aniline crystallises out, weakening the bath, and causing spots by 
 adhering to the pieces, which were sometimes even charred by the rise of 
 temperature taking place on lifting them out of the solution. Persoz, to 
 overcome these difficulties, causes the pieces to pass through a spray produced 
 by the rapid rotation of brushes in each of the solutions. The same author 
 has examined which aniline salts are practically best suited for dyeing a 
 good black. The tartrate, oxalate, and citrate are either too dear or unfavour- 
 able. The experiments were consequently limited to the sulphate, nitrate, 
 and hydrochlorate of aniline. He finds that, for dyeing, the employment of 
 the neutral aniline salts is to be avoided ; the binacid salts, especially the 
 bisulphate, give good results, though among the hydrochlorates the teracid 
 salt is preferable. A mixture of bisulphate and terhydrochlorate of aniline 
 gives the best results, the reddish cast of the one being compensated by the 
 blue shade of the other. The solution of bichromate of potash should be 
 used in a concentrated form, not less than 80 grms. per litre. 
 
 It makes little difference in the results if the bichromate of potash is 
 applied before or after the aniline salts, or at the same time. The texture 
 may therefore be completely impregnated with the bichromate solution, and 
 immediately after exposed to the spray of the aniline solution. The black 
 appears at first dark green. To develope the colour it is only necessary to 
 wash the goods in water, and then pass through a hot soap bath. 
 
 It has been already mentioned that aniline black has a greater affinity for 
 vegetable than for animal blacks. In 1865 Mr. Lightfoot patented a process 
 for applying the aniline black to wool. A solution is prepared with 1 kilo, of 
 dry hypochlorite of lime to 10 litres of water for every kilo, of wool. This 
 bath is composed of — 
 
 Water 60 litres. 
 
 Solution chloride of lime 1*3 kilos. 
 
 Hydrochloric acid 180 grms. 
 
COLOURED DERIVATIVES OF PHENOL. 
 
 215 
 
 The temperature of the bath is raised to 38 C, and the wool is worked in it 
 till it has acquired a yellowish colour; it is then withdrawn, washed, and 
 dried. Wool or woollen goods thus prepared are then treated in the ordinary 
 manner, either with Lightfoot's or Lauth's patent black. 
 
 Besides the above-described blacks mention must be made of the aniline 
 black pigment of Roberts, Dale, and Co. It is perhaps the best black known 
 for topical printing with albumen colours, as it does not, like logwood blacks, 
 tarnish the Ginguets, greens, or ultramarine blues. 
 
 The Lucas black, otherwise known as " Noir d'Aniline Lucas," or 
 " Petersen's Aniline Black," though much praised at first, has found its level. 
 According to the analysis of Rheineck, it consists of a mixture of hydro- 
 chlorate of aniline, and chlorides of copper, iron, and calcium. It finds no 
 favour either with dealers or consumers, and an account of its bad properties 
 has no longer any special technical interest. 
 
 The accompanying specimen is printed with the above-mentioned mixture 
 
 Aniline Black. 
 
 of hydrochlorate of aniline, chlorate of potassa, soda, or ammonia and 
 sulphide of copper added immediately before using. After ageing for two 
 nights the goods are washed off in a hot solution of silicate of soda, washed, 
 soaped, and re-washed. 
 
 COLOURED DERIVATIVES OF PHENOL. 
 
 Synonyms: — Carbolic Acid, Phenic Acid, Phenic Alcohol, Hydrate of Phenyl, 
 Phenylatcd Water. 
 
 Phenol is a solid, colourless body, crystallising in long needles, which 
 belong probably to the rhombic system. It has an empyreumatic odour and 
 a burning taste. If touched it attacks the skin, producing white blisters. Its 
 specific gravity is 1-065 ; it liquefies at 34 to 35 C.'and boils between 187 
 and 188 . Phenol is soluble in alcohol and ether, in concentrated acetic acid, 
 in the tar oils, and in glycerine. It is slightly soluble in water, from which it 
 can be separated by adding saline matter. It is capable of combining with 
 

 
 
 — .; B H 
 
 216 
 
 DYEING AND CALICO PRINTING. 
 
 bases, yet it does not redden litmus, and dissolves alkaline carbonates without 
 expelling the carbonic acid. 
 
 Phenol is extracted from the medium and the heavy coal-tar oils by a some- 
 what tedious process, which we need not here particularise, but which consists 
 in successive treatment with acid and alkaline liquids. The latter, generally 
 soda, takes up phenol along with the cresylic and phlorylic ncids. (See 
 Reimann's " Handbook of Aniline," p. 144). Among its most important 
 derivatives is the rosolic or phenoic acid, or aurine, formed by oxidation, 
 and first obtained by Runge. 
 
 Dr. R. Angus Smith prepares rosolic acid by heating in a capsule 2 parts of 
 commercial phenol, with 1 of caustic potash dissolved in a little water, and 
 5 of peroxide of manganese. A high temperature is required. The resulting 
 mass is dissolved in water, and the alkaline rcsolate is decomposed with a 
 suitable quantity of an acid. 
 
 Tschelnitz mixes the heavy tar oils with an excess of hydrate of lime, and 
 leaves the whole in a warm airy place for several months. The red mass thus 
 obtained is powdered and treated with dilute sulphuric acid with the aid of 
 heat. A dense oily scum rises to the surface, and is collected and boiled in 
 water as long as any oily products are volatilised. The fixed residue, when 
 cold, is placed on a filter, washed in water, dried, and treated with alcohol, 
 which dissolves rosolic and brunolic acids. This solution, treated with milk 
 of lime, gives a rose-coloured solution of rosolate of lime, whilst the brown 
 brunolate is chiefly precipitated. Pure rosolic acid is obtained by precipitating 
 the rosolate of lime with acetic acid, and combining it again with lime. This 
 treatment is repeated several times, traces of brunolic acid being eliminated 
 on each occasion. It is finally dissolved in alcohol, and on evaporation 
 remains as a hard vitreous body of an orange colour. 
 
 Persoz mixes 3 parts of carbolic acid, 2 of oxalic, and 2 of sulphuric. The 
 carbolic should boil at the constant temperature of 184° C, and the oxalic 
 should be perfectly dry. The whole is heated for some hours to a moderate 
 temperature. During the reaction there is effervescence, the mass thickens, 
 and takes a brownish red colour. The process is at an end when a drop of 
 the mixture, thrown into dilute ammonia, gives an intense red colour. It is 
 then withdrawn from the fire and poured into cold water, which extracts the 
 greater part of the sulphuric acid as well as the sulphophenic acid which has 
 been formed. It is then repeatedly washed with boiling water. On drying it 
 becomes a hard brittle mass, with a green reflection. Rosolic acid gives a 
 variety of fine red shades^ which can be easily modified by the aid of reagents. 
 Its unstable character renders the fixation of aurine upon fibres and tissues 
 a matter of some difficulty. The accompanying specimen of " Aurine 
 Orange " was obtained as follows : — Mix well 8 ozs. of aurine solution and 
 1 gallon of lactarine thickening. The " thickening " is prepared with — 
 7 pints Water at 80° F. 
 
 1 pint Ammonia, 
 
 2 lbs. Lactarine. 
 
 Stir well until perfectly dissolved. The colour is printed, and steamed for 
 twenty minutes. 
 
 The salts of rosolic acid with the alkaline earths and with lead are now 
 very largely employed in paper staining under the trade-name — very misleading 
 
COLOURED DERIVATIVES OF PHENOL. 
 
 217 
 
 Aurine Orange. 
 
 — of Turkey red. It retains, however, its importance as the raw material for 
 the preparation of peonine, or coralline. 
 
 This colouring matter was discovered by the younger Persoz, in 1859. To 
 prepare it we introduce into a strong iron vessel, capable of being closed by 
 means of screws, 1 part of rosolic acid and about 3 of commercial ammonia. 
 The vessel is heated in an oil-bath for three hours to a temperature not 
 exceeding 150 . When cool, the contents of the vessel appear as a thick 
 liquid with a golden crimson reflection. The colouring matter is precipitated 
 from this liquid by the addition of hydrochloric acid. If well prepared, peonine 
 is almost insoluble in water, but very soluble in alcohol, to which it com- 
 municates a red colour. Its alkaline solutions gradually take a brown colour 
 on exposure to the air. 
 
 Coralline Yellow. 
 
aBESEI^ES*M*EVS-«^F«^K-l»«'':.*>.l 
 
 218 
 
 DYEING AND CALICO PRINTING. 
 
 In dyeing with coralline the bath is prepared as follows: — The colour is 
 dissolved in alcohol, a little soda added, and the alkaline liquid poured into 
 a large quantity of water. By a slight addition of tartaric acid the colour is 
 set at liberty without being precipitated. In this bath shades are obtained 
 intermediate between those of cochineal and magenta. Cotton requires to be 
 previously mordanted with tin-salt and sumac or gall-nuts. The goods are 
 then entered into the colour-bath, which should be lukewarm, and are worked 
 for ninety minutes. For a full shade 500 grammes of coralline are consumed 
 per piece. The shade obtained resists steaming and washing, but is quickly 
 affected by soap, alkalies, and light. By a momentary exposure to ammonia 
 it may be modified to a carmine, but this colour is exceedingly unstable. 
 
 Coralline thrown down from its solution in acetic acid by the addition of 
 water, and dried at a temperature below its point of fusion, is a fine red 
 powder, which can be printed as a pigment colour by means of albumen. 
 
 Yellow coralline is a modification of the above colour ; the exact mode of 
 the preparation has not been made public. It yields upon wool very fine orange 
 shades, which are thus obtained : — 2 .J kilos, of yellow coralline are dissolved 
 in 10 litres of caustic soda at io° B. at the temperature of 60° C. It is 
 poured into 100 litres of water, heated again, and when completely dissolved 
 1 litre of bichloride of tin at 55° B. is added, previously diluted with 5 litres 
 of water. On filtering we obtain 20 litres of a bright orange lake. 10 litres 
 of this without previous washing are mixed with 2 kilos, of powdered gum 
 and 350 grms. of oxalic acid. The mass is heated till the gum and acid are 
 dissolved, strained, and printed on wool. After twelve hours it is steamed 
 for forty minutes. 
 
 The accompanying specimen of coralline yellow is produced by the 
 
 following process. The colour is dissolved in dilute ammonia to the strength 
 
 of 32 Tw. One measure of this solution is mixed with 4 measures of starch 
 
 paste, containing 14 lbs. per gallon, printed, dried, and steamed for one hour. 
 
 The following formula gives a good red upon delaines, resembling Turkey 
 
 red: — 
 
 Red coralline 80 grms. 
 
 Dissolve in a hot mixture of ^ litre of glycerine and J litre of water. In a 
 separate vessel 140 grms. of calcined magnesia are stirred up in \ litre of 
 water. The whole is then mixed together with f litre of solution of gum, 
 containing 500 grms. per litre. 
 
 Another derivative of phenol is picric acid, otherwise known as trinitrated 
 phenic acid, carbazolic acid, nitrophenisic acid, nitropicric acid, &c. It is 
 produced by the action of nitric acid upon indigo, silk, aloes, the resin of 
 Xanthorrhea hastilis, and especially phenol. The present mode of manu- 
 facture is to pass, in small quantities at a time, a stream of nitric acid into 
 pure carbolic acid, or into a previously formed mixture of carbolic and sulphuric 
 acids, or better still by attacking the crystalline sulpho-carbolate of soda with 
 nitric acid. Picric acid forms small brilliant yellow crystals, of an intensely 
 bitter taste, and moderately soluble in water. It dissolves in sulphuric and 
 nitric acids without change, and is re-precipitated on the addition of water. 
 Its tinctorial power is enormous, and its affinity for animal fibres is very great, 
 but upon vegetable fibres and tissues it can only be fixed by the aid of 
 animal mordants. With bases picric acid forms a series of well-defined salts, 
 
ISOPURPURIC ACID. 219 
 
 which are in general soluble, crystallisable, yellow, and which if heated, 
 especially in a closed vessel, explode with great violence. The picrate of 
 soda is sometimes sold to dyers under the name of aniline-yellow, but its 
 use requires care. Picric acid dyes upon silk and wool shades varying in 
 depth from a straw-yellow to a maize. Wool is easily dyed either hot or cold, 
 and is often previously mordanted with alum and tartar to render the colour 
 faster. Picric acid is also used along with extract of indigo, and with 
 Prussian blue, for producing greens, and in modifying the tone of the aniline 
 greens. 
 
 The intensity and purity of a sample of picric acid may be known by 
 dyeing known weights of wool or silk with a given quantity of the dye, and 
 comparing the shades produced with those furnished by a standard sample. 
 It is frequently adulterated with a variety of articles, such as sulphate of soda, 
 borax, oxalic acid, alum. These impurities are easily detected by dissolving 
 the sample in benzol, warming the tube gently by plunging it into lukewarm 
 water. The impurities remain insoluble. 
 
 Picramic acid maybe prepared by dissolving 1 part of picric acid and 7 parts 
 of piotosulphate of iron in hot water, and adding a boiling solution of caustic 
 baryta. A deep red liquid is obtained, containing the picramate of baryta. 
 Girard saturates with ammonia picric acid dissolved in alcohol, and treats the 
 solution with an excess of sulphuretted hydrogen. The liquid takes a dark 
 red colour, and deposits a mass of deep red crystals, the picramate of ammonia. 
 This salt is dissolved in boiling water, mixed with an excess of acetic acid 
 and allowed to cool. Picramic acid crystallises after a time in the form of 
 tables or needles of a brilliant garnet red. It is easily soluble in alcohol and 
 ether, sparingly in water, even when hot. Both picramic acid and the soluble 
 picramates are true dyes, capable of fixing themselves upon animal fibres but 
 they have not yet found their way into commerce. 
 
 Isopurpuric Acid. 
 (Picric Red, Picrocyanic Acid, Homorceine, Soluble Garnet.) 
 This colour is prepared by dissolving 2 parts cyanide of potassium in 4 parts of 
 water at 60°. A solution of r part of picric acid in 9 parts of boiling water is then 
 gradually added with constant stirring. On cooling there is formed a crystalline 
 mass. This is thrown on a table, pressed , stirred up in a little water, filtered anew 
 and washed with cold water. The residue is purified by re-solution in boiling 
 water, and re-crystallisation. The potash salt thus obtained is dissolved in 
 a small quantity of hot water, and a solution of sal-ammoniac is added. It 
 is deposited in wedge-like crystals, of a reddish brown colour, with metallic 
 green reflection. The isopurpurate of ammonia was at one time considered 
 identical with the purpurate of ammonia (murexide). A careful comparison 
 of the shades produced by these two dyes under identical conditions proves 
 a decided difference. Isopurpurate of ammonia has been prepared on a com- 
 mercial scale by Messrs. Roberts and Dale, of Manchester, and yields beautiful 
 and peculiar reddish purples on wool, leather, and silk. Its use, however is 
 still very limited. When dry the isopurpurates explode with a fearful violence 
 on the least shock. Hence they should be preserved in a paste with water 
 and a little glycerine, which prevents drying up. 
 
m 
 
 
 e"fi«? «■/*»* 
 
 
 BWBBPWBBI 
 
 220 DYEING AND CALICO PRINTING. 
 
 Rothine, or Phenicienne. 
 
 (Not to be confounded with phoenicine). This colour was discovered by 
 Roth in 1863, and has been prepared on a large scale at Mulhouse. It is 
 obtained by pouring nitrosulphuric acid upon carbolic acid. The proportions are 
 10 to 12 parts of the former to 1 of the latter. A small part of the nitro-sulphuric 
 acid is added at first, and the rest is added in successive portions as the reaction 
 ceases, until no more orange vapours are given off on the last addition of acid. 
 The whole is then thrown into a large quantity of water. An abundant brown 
 precipitate is immediately formed, which, when collected, washed, and dried, 
 is phenicienne. The washing is a tedious process, lasting several days. The 
 colour is sparingly soluble in cold, and completely insoluble in hot, water ; 
 very soluble in ether, alcohol, and acetic acid, especially if a little tartaric 
 acid has been added previously. Phenicienne is also readily soluble in 
 alkaline liquids. It furnishes a great variety of solid shades, according to 
 the mordants employed. It resists sunlight, and even chloride of lime. The 
 shades which it yields surpass in purity and brightness all similar colours 
 obtained with the woods and orchil. It has certain analogies with catechu, 
 and its shades are heightened in a similar manner by metallic salts capable of 
 exerting an oxidising action. 
 
 With silk and wool it is a substantive colour, the shades produced varying 
 from a deep garnet to a deep chamois, according to the concentration of the 
 colour-bath and the oxidising agents employed. 
 
 Cotton goods are previously mordanted with tannin and stannate of soda. 
 Alkalies give the colour a blue cast, but the dye is then attacked by soap. 
 
 Phenicienne does not give satisfactory results in printing, even on wool and 
 silk ; the process of steaming destroying its brilliancy. 
 
 Vesuvine. 
 This is a colour discovered by Knorp, of Stuttgardt. Its nature and pre- 
 paration have not been closely described, but it is probably identical with the 
 dye patened by Messrs. Roberts and Dale, as " Manchester Brown," and pro- 
 duced by the action of alkaline nitrites on phenylen-diamine. Vesuvine dyes 
 orange and light brown shades. For use it is dissolved in tepid water and 
 filtered. This solution dyes wool and silk at the heat of 87 or 88" C. The 
 addition of hyposulphite of soda to the extent of one-tenth the weight of the 
 colour is advantageous as regards wool. A variety of brilliant shades can be 
 produced by the addition of a solution of chloride of tin neutralised with 
 ammonia. Cotton tissues are first prepared with sumac ; then woikcd in 
 weak stannate of soda, wrung out, passed through water slightly acidulated 
 with sulphuric acid, rinsed in cold water, and worked in the dye-bath. 
 
 NAPHTHALIN COLOURS. 
 Naphthalin was discovered in coal-tar in 1820, and was first investigated by 
 Faraday in 1826. Its percentage composition is — 
 
 Carbon 937 
 
 Hydrogen 6-2 
 
 99-9 
 
 and its formula is C 10 Hg. 
 
NAPHTHALTN COLOURS. 221 
 
 When pure it is a colourless solid of peculiar smell and taste. Its specific 
 gravity is i'i53. It melts at 79° C, and boils at 220 C. It is insoluble in 
 cold water, sparingly soluble in boiling water, but dissolves readily in alcohol, 
 ether, the fatty and essential oils, and in acetic acid. It dissolves easily 
 sulphur, phosphorus, indigo, iodine, the iodides of lead and mercury, the 
 sulphides of arsenic, tin, and antimony, and arsenicus acid. 
 
 The derivatives of naphthalen are almost innumerable, and many colouring 
 matters are produced by its reactions, few of which, however, have found their 
 way into commerce. Among the most important of its produces we mention 
 naphthylamine, which yields a red and a violet dye. This substance is com- 
 posed of — 
 
 Carbon 83-91 
 
 Hydrogen 7-55 
 
 Nitrogen 8*54 
 
 IOO'OO 
 
 and has received the formula, Ci H 9 N. 
 
 It is a solid body, crystallising in colourless needles, of offensive odour, and 
 burning taste. It fuses at 50 , and sublimes at 300 . In water it is almost 
 insoluble, but it dissolves readily in alcohol and ether. It combines with the 
 acids to form salts, which, on exposure to the air or to oxidising agents, take 
 a red or violet colour. 
 
 Naphthylamine Violets. 
 One kind of violet resulting from the above-mentioned action of oxidising 
 agents upon the salts of naphthylamine was discovered by Piria, in 1851. Its 
 constitution is unknown. The other kind is produced by the action of dehydro- 
 genisers upon naphthylamine at the temperature of 200 . Their production 
 generally accompanies that of naphthylamine red. Neither of these violets 
 has yet been prepared on a large scale. 
 
 Naphthylen Diamine Violets. 
 
 These colours result from the action of reducing agents upon binitro- 
 naphthalin. Troost prepares them by treating binitro-naphthalin with 
 sulphides, cyanides, and sulpho-cyanides in presence of an alkali, which must 
 not be allowed to act before the reducing agent. The violet bodies produced 
 dissolve in alkalies, alkaline carbonates, and alcohol, from which they are 
 precipitated unchanged by dilute acids. 
 
 Roussin treats binitro-naphthalin with proto-salts of tin dissolved in caustic 
 alkali. If the heat of the water-bath be applied the reaction is complete 
 when the temperature reaches 8o c . The mixture is then thrown upon a filter, 
 and washed as long as anything is dissolved. A violet-blue powder remains 
 on the filter, easily soluble in alcohol and wood-spirit, and capable of dyeing 
 fast shades. 
 
 Naphthalin Yellow. 
 
 Martius has patented the manufacture of a yellow dye by adding an 
 
 alkaline nitrite to an acid solution of the hydrochlorate of naphthylamine. 
 
 When a little of the liquid thus obtained gives a cherry-red with alkalies, it is 
 
 mixed with a large quantity of nitric acid and boiled. The resulting acid is. 
 
^«WPVff«^»W^X2S-?.V^ 
 
 BBPBB HBBBBIPI 
 
 222 DYEING AND CALICO PRINTING. 
 
 of a pale yellow colour, and forms beautiful crystals with the alkalies and 
 alkaline earths. The lime-salt is largely manufactured by Messrs. Roberts 
 and Dale, and is known under the trade-names of Manchester Yellow and 
 Jaune d'Or. Its tinctorial power is still greater than that of picric acid, to 
 which it is in many respects analogous. Indeed, it may be regarded as a 
 picric acid, in which the radical phenyl is replaced by naphthyl. It produces 
 upon silk, wool, and leather bright shades of a true gold colour, without the 
 greenish cast of picric acid. These colours bear the steaming process, which 
 is not the case with those obtained with picric acid. 
 
 It was at one time thought that alizarin had been obtained artificially from 
 naphthalin. This opinion proved to be unfounded, but artificial alizarin, as 
 we shall see below, is produced by another of the coal-tar products. 
 
 Many of the coloured reactions of naphthalin and its derivatives invite 
 further research. 
 
 ANTHRACEN COLOURS. 
 Artificial Alizarin. 
 Anthracen is a solid body, existing in the heavy oils of coal-tar. It is met 
 with in the last portions, which distil after napthalin. It is not equally 
 plentiful in all tars, but is chiefly found in those which are rich in benzol and 
 naphthalin, poor in toluen. According to Berthelot, toluen at a red heat 
 yields anthracen as the principal product of its decomposition. If the 
 existence of anthracen in coal-tars is due to the previous destruction of a 
 part of the toluen which they contain, the rarity of the one substance must 
 correspond with the abundance of the other. On the large scale anthracen 
 is prepared as follows : — If coal-tar is distilled in the usual manner it yields 
 on the average per ton 13 to 14 litres of ammoniacal gas-liquor ; 29 to 30 
 of very light oils, containing benzol; 90 to 100 of light oils, containing a 
 little benzol. If the distillation is continued, 300 to 312 litres of heavy oils 
 are collected, and the residue is merely hard pitch. The heavy oils consist of 
 naphthalin, phenol, cresol, and similar products, and contain besides more or 
 less anthracen. The last-mentioned body passes over towards the end of the 
 process. When the fatty matter which distils over shows a yellowish green 
 colour, and congeals to a pasty consistence on cooling, it is collected separately. 
 It contains about 20 per cent of anthracen, and is used as the chief material 
 for its preparation. The mass is placed in a centrifugal machine to expel 
 the oil as far as possible. The residue, which still contains much oil, is heated 
 to about 40 C, and introduced into a powerful hydraulic press, which should 
 V>e provided with plates capable of being heated like an oil-press. The residue, 
 after pressing, contains about 60 per cent of pure anthracen. In this state 
 it is a greenish, tolerably dry mass. It is then treated with light tar-oil or 
 with petroleum-naphtha, boiled and allowed to cool, or extracted by percolation. 
 The light oil dissolves the residue of naphthalin and the heavy oil, whilst 
 pure anthracen moistened with naphtha remains behind. This pure 
 anthracen is again extracted in the centrifugal, placed in a boiler, and heated 
 to the melting-point, when the residues of the light oils distil over. There 
 remains a greenish-white, paraffin-like mass of fine crystalline fracture, con- 
 taining 95 per cent of pure anthracen, and melting at 205 to 208 C. By 
 sublimation pure anthracen is obtained in small lamellar crystals, which melt 
 at from 212 to 215 . A trustworthy method for determining the amount of 
 
ARTIFICIAL ALIZARIN. 
 
 223 
 
 pure anthracen, either in commercial anthracen or in crude green grease is 
 the following : — The melting-point of the sample in question is first determined. 
 5 to ro grms. are sufficient for the operation. It is put between thick folds of 
 blotting paper, and placed under a press, between plates which have been 
 previously warmed. The anthracen remaining upon the paper after pressure 
 is weighed. The residue, after it has been boiled with a certain quantity of 
 alcohol, filtered, washed with cold alcohol, and dried, is weighed as pure 
 anthracen. It is now advisable to determine the melting-point of the 
 purified product, which will generally be 210 C. 
 
 The methods by which anthracen may be extracted from the less volatile 
 oils and from the residual pitch need not be here described. The products of 
 anthracen are very numerous, but the only one which concerns us is artificial 
 alizarin. Its preparation, according to the earliest patent of Graebe and 
 Liebermann, is as follows: — Purified anthracen (C I4 H I0 ) is converted into 
 anthrachinon, C I4 H80 2 , either — 
 
 1. By treating 1 part of anthracen with 2 parts of bichromate of potash 
 
 and sulphuric acid, with or without acetic acid. 
 
 2. By oxidising anthracen with bichromate of potash, both dissolved in 
 
 acetic acid. 
 
 3. By oxidising anthracen with nitric acid of mediu-m concentration, and 
 
 simultaneous application of concentrated acetic aci,d- 
 The anthrachinon thus obtained is converted into C I4 H6Br 2 3 by heating 
 1 equivalent of anthrachinon and 4 equivalents of bromine in closed vessels, 
 for several hours, to the temperature of 8o° to 130 C. The bibrom- 
 anthrachinon is then heated in closed vessels, with concentrated soda or 
 potash-lye, to 180 to 260 C, in order to replace the bromine with peroxide 
 of hydrogen. The mixture slowly assumes first a blue and then a violet 
 colour, which gradually becomes more intense. When the depth of colour no 
 longer increases the mass is allowed to cool, dissolved in water, filtered, and 
 supersaturated with sulphuric or hydrochloric acid, when alizarin separates 
 out in yellow flakes, which are filtered and purified by washing with water. 
 
 The third patent of the same chemists (dated November 3, 1869, and 
 January 18, 1870) directs the preparation of artificial alizarin as follows : — 
 
 One part of anthrachinon is mixed wiih about 3 parts of concentrated sul- 
 phuric acid (sp. gr. 1-848), and the mixture is heated in a suitable vessel till a 
 portion poured into water dissolves completely, and leaves only traces of 
 unchanged anthrachinon. It is then allowed to cool, and diluted with water. 
 In ordier to remove the excess of sulphuric acid it is accurately saturated with 
 chalk. Sulphate of lime is thrown down, and is removed by filtration and 
 powerful pressure, whilst anthrachino-bisulphate of lime remains in solution. 
 As this salt is insoluble in cold water, this operation should be conducted at a 
 boiling heat. The hot solution is mixed with a solution of carbonate of soda, 
 likewise hot, till the reaction is alkaline. The mixture is boiled for some time, 
 till the carbonate of lime is deposited in a heavy granular state. The solution 
 of anthrachino-bisulphate of soda is separated by decantation and filtration, 
 and evaporated to dryness. To 1 part of the dry salt, 2 or 3 parts of solid 
 soda and a little water are added. The mixture is then heated in iron vessels 
 to 180 to 260 C, till the fused mass has an intense violet colour, and a 
 portion dissolved in water and mixed with dilute sulphuric acid gives a copious 
 

 
 m& 
 
 
 mm iHiuwMHum 
 
 224 
 
 DYEING AND CALICO PRINTING. 
 
 brownish-yellow deposit. When this point is reached the mass is allowed to 
 cool, dissolved in hot water, the deep blue violet liquid decanted or filtered 
 from the undissolved residue, and the clear filtrate mixed with sulphuric or 
 hydrochloric acid. Sulphurous and carbonic acids are evolved, whilst alizarin 
 is deposited in dense brownish-yellow flakes. These, when cold, are collected 
 on a filter, and perfectly washed with cold water. The alizarin can serve for 
 all purposes to which the preparations of madder were formerly applied. 
 
 Anthrachinon-bisulphuric acid is prepared from anthracen as follows : — 
 1 part of anthracen is heated in a suitable vessel with 4 parts of concen- 
 trated sulphuric acid, at first for 3 hours to ioo°, and afterwards for another 
 hour to 150 . The mass, when cold, is mixed with three times its weight of 
 water. If unchanged anthracen is deposited, it is collected, washed, dried, 
 and set aside for a future operation. The strongly acid dark coloured solution 
 contains anthracen-bisulphuric acid and much free sulphuric acid. It is heated 
 to boiling, and peroxide of manganese in powder is added to thrice the weight 
 of the anthracen employed. The boiling is kept up till the anthracen- 
 bisulphuric acid is converted into anthrachino-bisulphuric acid. The mixture 
 should be evaporated to dryness, and the heat continued for some time. The 
 mass is now dissolved in boiling water, and dilute milk of lime is added, till 
 the liquid has an alkaline reaction. Insoluble protoxide of manganese is 
 deposited along with sulphate of lime, whilst anthrachino-bisulphate of lime 
 remains in solution. All insoluble matter is removed by filtration and 
 pressing, and the residual solution of anthrachino-bisulphate of lime is 
 decomposed by means of carbonate of soda. The solution is evaporated to 
 dryness, and converted into alizarin by treatment with acids. 
 
 Dale and Schorlemmer have patented a still simpler process : — 1 part of 
 anthracen is boiled for some time with 4 to 10 parts of strong sulphuric acid 
 It is then diluted with water, and the solution neutralised with carbonate of 
 lime, baryta, soda, and potash. The sulphates are then removed by filtration 
 or crystallisation. The resulting solution is heated to 180 to 260 C, along 
 with caustic soda, to which a quantity of saltpetre or chlorate of potash, 
 equal in weight to the anthracen originally employed, has been added, until 
 the deep blue-violet colour is developed. The alizarin is then thrown down 
 with acids in the usual manner. 
 
 The alizarin of commerce generally forms a thin paste, containing about 
 15 per cent of solid matters, alizarin, anthrachinon, and oxyanthrachinon. 
 To prepare from this paste pure alizarin it may be dissolved in dilute caustic 
 soda and filtered. The filtrate is mixed with chloride of barium, boiled, 
 filtered, and the precipitate is well washed with water, then suspended in 
 water, and decomposed with hydrochloric acid. The orange-coloured preci- 
 pitate is filtered, washed, dried, and sublimed, when pure alizarin is 
 obtained. 
 
 The identity of artificial and natural alizarin was for a time doubted, in 
 consequence of experiments made with impure products. Certain chemists 
 found that tissues dyed with artificial alizarin lost a considerable amount of 
 colour on treatment with soda-lye. This result was probably due to the 
 presence of tinctorial matters other than alizarin. The artificial alizarin 
 paste of Gessert and of Lucius has, according to Bolley, ten to twelve times 
 the tinctorial power of Italian garancin. For the properties of alizarin the 
 
ARTIFICIAL ALIZARIN. 
 
 225 
 
 reader is referred to, the section on the madder colours, where also will be 
 found a specimen dyed with artificial alizarin for comparison with a 
 Turkey red. 
 
 The following recipes for printing with artificial alizarin will be foond 
 useful : — 
 
 Reds. 
 
 5 lbs alizarin paste (10 per cent) ; 
 16 lbs. thickening.; 
 1 lb. acetate of alumina, at 15 Tw. ; 
 £ lb. acetate of lime, at 25 Tw. 
 
 Pinks. 
 
 The same, diluted with 2 or 3 parts of thickening. 
 
 For double printing, when deep red is printed on first, the goods must be 
 steamed one hour before the second printing takes place. After the second 
 printing the goods are again steamed for one hour and aged for twenty-four 
 hours ; they are then passed through one of the following baths, at from 120 
 to 140 F., remaining in the bath not longer than 1 to i£ minutes : — 
 250 gals, water ; 
 60 lbs. chalk ; 
 3 lbs. tin crystals. 
 Or 250 gals, water ; 
 40 lbs. chalk ; 
 10 lbs. arseniate of soda. 
 The goods are then washed and cleared as follows :— Take for 10 pieces of 
 50 yards each — 
 
 1st soaping, at 120 F., 3 lbs. soap; \ lb. tin crystals. 
 2nd ,, at 160° F., 3 lbs. soap. 
 3rd ,, at 175 F., 3 lbs. soap. 
 Wash between each soaping. 
 
 Red for Mosaics. 
 
 8 lbs. alizarin paste (10 per cent) ; 
 10 crnarts thickening ; 
 
 9$ ozs. nitrate of alumina, at 23 Tw. ; 
 19 ozs. acetate of alumina, at 15 Tw. 
 13 ozs. acetate of lime, at 25 Tw. 
 Or 10 lbs. alizarin paste (10 per cent) 
 10 quarts thickening; 
 13 ozs. nitrate of alumina, at 23 Tw. 
 19 ozs. acetate of alumina, at 15 Tw. 
 16 ozs. acetate of lime, at 25 Tw. 
 
 Another Red without Oil. 
 
 8J lbs. alizarin paste (10 per cent) ; 
 gj lbs. acetic acid, at 12 Tw. ; 
 3i lbs, wheat flour ; 
 5 pints water. 
 
■H 
 
 
 sH^cBBBHflBBH 
 
 DYEING AND CALICO PRINTING. 
 
 Boil well, and stir till cold ; then add — 
 
 i lb. acetate of lime, at 29 Tw. ; 
 
 2 lbs. nitrate of alumina, at 23 Tw. ; 
 
 3 lbs. hyposulphite of lime, at 13 Tw. 
 
 Purple. 
 
 3 lbs. alizarin paste (10 per cent) ; 
 10 quarts purple thickening ; 
 
 6 ozs. pyrolignite of lime, at 18 Tw. ; 
 12 ozs. acetate of lime, at 25° Tw. 
 The printed goods are steamed for an hour or tsvo, and then aged for twenty- 
 four to thirty-six hours. They are then padded in the chalk and arseniate of 
 soda bath ; after which they are washed and soaped in a single soap -bath 
 without tin-crystals, and if needful cleared in a weak solution of bleaching- 
 powder. , 
 
 Thickening for Reds. 
 
 12 lbs. wheat starch ; 
 40 quarts water ; 
 
 4 quarts acetic acid, at 9 Tw. ; 
 ii lbs. gum tragacanth ; 
 
 2 lbs. olive oil ; 
 Boil well together, and stir till cold. 
 
 Thickening for Purple. 
 
 10 lbs. starch ; 
 27 quarts water ; 
 
 3 quarts acetic acid ; 
 
 ii lbs. gum tragacanth ; 
 2 lbs. olive oil. 
 Boil well together, and stir till cold. 
 The mordants in the above recipes are prepared as follows : — 
 
 Acetate of Alumina. 
 
 Stir 30 lbs. hydrate of alumina into 6 quarts of acetic acid, warm, filter, and 
 reduce to the specific gravity required. 
 
 The hydrate of alumina is prepared by dissolving 72 lbs. alum in 100 gals, 
 water, and 62 lbs. soda in 100 gals, water. The two solutions are mixed, the 
 precipitate is washed eight times by decantation, collecled on a filter, and 
 pressed. It must be dissolved on the filter before it gets dry. 
 
 Nitrate of Alumina. 
 2 lbs. nitrate of lead ; 
 2 lbs. alum ; 
 2 quarts water. 
 Dissolve and filter off the liquid from the precipitate, and dilute to proper 
 standard. 
 
 The reds are turned more yellow by nitrate than by acetate of alumina, and 
 when the former is used more acetate of lime is taken in addition. 
 
ARTIFICIAL ALIZARIN. 
 
 227 
 
 Acetate of Lime. 
 A solution of acetate of lime at 25 Tw. contains 25 per cent of acetate of 
 lime : generally T ' th of the weight of alizarin paste is required ; but with 
 a fresh quality of alizarin it is safer to ascertain, on a small scale, the amount 
 needed. 
 
 Brown. 
 13 J lbs. alizarin paste (15 per cent) ; 
 9 quarts thickening ; 
 2 lbs. nitrate alumina, at 29 Tw. ; 
 15 ozs. acetate alumina, at 19 Tw. ; 
 15 ozs. red prussiate of potash, dissolved in water; 
 1 lb. 1 oz. acetate of lime, at 29° Tw. 
 
 To obtain a yellower shade, for every quart of mixed colour, 1 oz. of bark 
 liquor, at 30 Tw., may be added. 
 
 Old spoiled red colours may be advantageously used for browns by adding 
 per quart J oz. to 1 oz. of red prussiate, dissolved in water. 
 
 Q 2 
 
»-<S«S*5**iVl9o 
 
 
 M 
 
 HiB^HB B9 
 
 228) 
 
 CHAPTER IV. 
 
 COLOURING MATTERS OF VEGETABLE AND ANIMAL ORIGIN. 
 
 MADDER AND OTHER RUBIACE^E. 
 
 OF all the dye-materials in general use none exceeds in importance 
 madder, which has become the basis of almost all our dyes." These words, 
 written in 1828 by Daniel Kcechlin-Schouch, are scarcely out of date even at 
 the present day. Madder owes its importance to the beauty and fastness of 
 the tints it yields, and to the fad that by a simple variation of the mordants 
 used it produces red, rose-pink, black, violet, lilac, and puce colours. Though 
 alizarin, the chief colouring matter of madder, is now produced artificially in 
 laige quantities, madder will long remain in request, especially for woollen 
 dyeing. 1000 tons of coal should theoretically yield 1 ton of alizarin ; in 
 pradice the amount obtained does not exceed one-half of this estimate. The 
 future of artificial alizarin depends on an increased supply of anthracen. 
 
 Madder, garance (Fr.), meekrapp (Dutch), krapp (Germ.), robbia (Ital.), 
 is the ground root of a plant known to botanists as Rubia tinctorum. 
 It is originally a native of Central Asia and the table-lands of the Caucasus. 
 This root has been cultivated from a remote antiquity, — so remote, indeed, 
 that it is very difficult to say where its true habitat may be. Its cultivation in 
 the neighbourhood of Smyrna, Adrianople, the Isle of Cyprus, and some parts 
 of the present kingdom of Greece, is mentioned by ancient historians. Dios- 
 corides and Pliny state that madder was used by the Egyptians, Persians, and 
 Indians. The ancient Greeks and Romans were acquainted with this plant 
 under the names of Erythrodanon and Rubia. About the time of the Crusades 
 the cultivation of madder was re-introduced into the more western parts of 
 Europe, especially into Italy, and perhaps into France. In some parts of 
 Spain it was grown by those enterprising agiiculluiists, the Moors, and 
 towards the middle of the sixteenth century it found its way into that portion 
 of the Netherlands known as Zealand. Charles Gaint caused it to be culti- 
 vated in Alsace, and Colbert introduced it into the Comtat d'Avignon in 1666. 
 In the city of Avignon the general tradition is that a certain Armenian, named 
 Joseph Althen, a native of Yulfa, a suburb of Ispahan, introduced the culture 
 of madder into the Comtat and the neighbouring principality of Orange, about 
 the years 1762 to 1774. A statue has been erected at Avignon in his honour, 
 and was inaugurated on the day that his only daughter died in an hospital. 
 The cultivation of madder in Alsace (late Departements du Haut et Bas Rhin) 
 is locally attributed to M. Franke, of Haguenau (1760). In our days madder 
 is cultivated, to a greater or less extent, in Italy, Roumania and other parts of 
 Turkey, the States of Barbary (Tunis, Morocco), various parts of Germany 
 
MADDER. 
 
 22Q 
 
 and of Spain; the provinces of Zealand, North Brabant, and Limburg, in the 
 Netherlands; some parts of Belgium, the Caucasus, the Levant, North and 
 South America, and Algeria. Its cultivation has never been carried on to any 
 extent in the United Kingdom. 
 
 The plant is an herbaceous perennial belonging to the natural order Rubiacea?, 
 or, on the old Linnean system, to the Tetrandria Monogynia. There are 
 three varieties of this plant in cultivation,— Rubia tinctorum, R. cordifolia, 
 and R. peregrina. The stems of the plant are squarish. The blossom is 
 yellow, and it is succeeded by a small berry containing the seeds. The 
 valuable portion of the plant is the root, which is long in proportion to its 
 thickness, and, except in some Levant roots, not exceeding a goose-quill in 
 diameter. This root consists of three distinct portions,— the epidermic cuticle, 
 the cortical fleshy and cellular ring, and the hard internal woody portion of a 
 fibrous structure. According to the researches made by M. E. Kcechlin, the 
 following proportions exist between the different portions of the roots, calcu- 
 lated for ioo parts of the fresh material:— Fleshy matter, 90*36, equal to 16-94 
 after drying ; ligneous parts, 9-64, after drying 4-68. The root alone contains 
 the colouring matter, and the name "madder" — or its equivalent in foreign 
 tongues— is rather incorre&ly applied to the living plant as well as to the dried 
 root, ground or whole, except that in many countries the unground root is 
 called " alizari " or " lizari." In commerce three kinds of madder are chiefly 
 distinguished, viz., Avignon, Alsatian, and Dutch. In addition, we shall 
 briefly mention the madders derived from other countries. The cultivation of 
 the so-called Avignon madder is chiefly confined to certain districts of the 
 Vaucluse which were once marshy, and which, having been drained, stretch 
 from l'lsles to Eutraigues, forming what are locally known as " paluds." 
 This soil is rich in humus, and in carbonate of lime, and is of a very open 
 texture. When dry it is almost white, but becomes brownish when moistened. 
 There is reason to believe that in former ages this part of France was entirely 
 submerged. Schlumberger found, on analysis, the composition of this soil to 
 be — after desiccation at ioo° C. — 
 
 Palud Distria. 
 
 Soil yielding 
 
 Rose-coloured 
 
 Madder. 
 
 I. II. Superior. Inferior. 
 
 Carbonate of lime 93 90 38 7 
 
 Insoluble in hydrochloric acid. . 65 50 90 
 
 Trace of oxide of iron. Trace of oxide of iron. 
 The palud roots are very rich in colouring matter, and exhibit in their centre 
 a deep red colouration. The roots grown in a soil richer in clay exhibit a 
 rather yellow — or, more correctly speaking, rose-pink — colour. As regards the 
 quality of the soil best suited to the cultivation of madder, it is difficult to give 
 a clear description, seeing that the crop succeeds well under widely different 
 conditions of soil, climate, and treatment. Thus there is no point of comparison 
 between the soils just referred to and the soil upon which madder is successfully 
 grown in the province of Zealand. Further, a difference of some io°of latitude 
 cannot fail to bring about a corresponding variation of climate. Whatever 
 may be the nature of the soils applied to the cultivation of it, it requires 
 careful tillage. The ground is ploughed to the depth of 60 to 80 cm., and is 
 well manured with rich but well-rotted horse-dung, or farm-yard manure. In 
 the Vaucluse, madder is sown about the month of March, and the young plant 
 
■ 
 
 
 230 DYEING AND CALICO PRINTING. 
 
 is very carefully tended and kept free from weeds. Experience having shown 
 that the older the root the richer it is in colouring matters, the plant is left in 
 the soil at the very least for eighteen months, but often for a longer time. 
 Care is taken to promote the development of the root by covering the portions 
 above ground with soil, thus preventing its too rapid growth. The plant 
 blooms in July, and the seed is colle.ifred in August. The plant is cut down 
 with sickles, the stem and leaves being used as food for cattle. In November, 
 the plant having been in the ground for eighteen months (which is technically 
 called two years) or 28 months (called three years), the root is dug out, an 
 operation which in the Vaucluse is performed by means of a specially- 
 constructed plough. The yield of roots at two years of age varies considerably, 
 but on the average amounts to 16,000 kilos, of fresh root per hectare, equal to 
 4000 kilos, of dried lizari. The price of the air-dried root in this district 
 varies from 65 to 70 francs per 100 kilos., and the department of the Vaucluse 
 produces yearly madder to the value of 25 to 30 millions of francs. The 
 dryness of the air and the heat of the sun suffice for the desiccation of the 
 root so as to fit it for the grinding-mill and for transportation. 
 
 The cultivation of madder in the Netherlands is chiefly, though not entirely, 
 confined to those parts of the country which have been reclaimed from the 
 sea, and are commonly termed " polders." The soil is chiefly a rich alluvial 
 clay, and does not contain nearly so much lime as the paluds district of the 
 Vaucluse. It may be advisable here to quote the full analysis, made some 
 years ago by Mulder, of the surface and subsoil of the best Zealand madder- 
 clays, of the earth from the palud district, and of the ash of the best Alsace 
 madder-root by Kcechlin, and of Zealand madder-root by Mulder. ' 
 
 Surface Soil, Zealand, Air-dried. 
 
 Sodium chloride o - oi3 
 
 Potassium silicate o - 484 
 
 Sodium silicate '3 X 4 
 
 Sodium carbonate 0064 
 
 Calcium sulphate 0*127 
 
 Calcium carbonate I3'058 
 
 Potassium carbonate o'ooo 
 
 Potassium chloride o*ooo 
 
 Manganic and ferric sesquioxides . . . . 3'387 
 
 Alumina I'2i8 
 
 Phosphoric acid 2*688 
 
 Subsoil from the Same Field. 
 
 Sodium chloride o - oi4 
 
 Potassium silicate ©"630 
 
 Sodium silicate o - oi2 
 
 Sodium carbonate 0*239 
 
 Calcium sulphate 0*248 
 
 Calcium carbonate 1 3'93° 
 
 Magnesium carbonate 0*69 
 
 Potassium carbonate 0^050 
 
 Manganic and ferric sesquioxides .. .. 2-310 
 
 Alumina i'305 
 
 Phosphoric acid 0500 
 
 Residue to make up 100, moisture, silicates, &c. insoluble in hydrochloric acid. 
 
MADDER. 231 
 
 Paluds Earth, Vaucluse. 
 
 Sodium chloride 0-135 
 
 Potassium silicate 0-288 
 
 Sodium silicate o - 26o 
 
 Calcium sulphate 0*576 
 
 Calcium carbonate 87-060 
 
 Magnesium carbonate 0-165 
 
 Potassium carbonate 0-121 
 
 Potassium chloride. . .. , o - oo6 
 
 Manganic and ferric sesquioxides . . . . 2-134 
 
 Alumina 0-720 
 
 Phosphoric acid 1*566 
 
 Magnesium sulphate 0-020 
 
 Ash of Alsace Madder (Kcechlin). 
 (Two samples grown in different fields). 
 
 I. II. 
 
 Potassa 29-35 2864 
 
 Soda x 5"89 11-67 
 
 Lime 34-54 29-25 
 
 Magnesia 3-72 3-68 
 
 Peroxide of iron 1-18 3-36 
 
 Phosphoric acid 5-26 4-62 
 
 Chloride of sodium 4-71 13*25 
 
 Sulphuric acid 3-68 2-14 
 
 Silica 164 5-36 
 
 Ash of Zealand Madder Root. 
 
 Potassa 25-48 
 
 Soda 21-91 
 
 Lime l 5'%4 
 
 Magnesia on 
 
 Peroxide of iron 10*18 
 
 Phosphoric acid 3'62 
 
 Chloride of sodium 7-72 
 
 Sulphuric acid 3-27 
 
 Silica 10*87 
 
 Madder is not grown from seed in Zealand, but shoots are planted in the 
 month of May, and put in well-tilled ground, in rows about 2 feet or more 
 apart. The plot is carefully weeded, and in the month of November following 
 the plants are covered over with earth, dug from between the rows, to preserve 
 them from frost. This treatment serves to increase the roots in length and 
 thickness. The roots are dug out with long narrow-bladed spades. 
 
 In Alsace the root is planted in a clay soil not containing much lime. The 
 plants are raised from seed, but the roots in shape resemble those of Zealand, 
 — that is, they form a bunch going 2 or 3 feet down into the soil, and occupying 
 a considerable surface, whilst Avignon madder is a long straight root with 
 small rootlets attached. The madder of commerce is the root ground 
 
232 
 
 DYEING AND CALICO PRINTING. 
 
 down to a powder, but it undergoes some previous operations to fit it for 
 grinding. The root when first dug out is very brittle, and is hence left on the 
 fields for twenty-four hours after being dug up, in order to grow tough. In 
 the Caucasus the root is washed in water, to remove adhering soil, — a process 
 which in Europe has been condemned as injurious without trial, and which 
 might be advantageously tried. After washing it is next placed in pits dug in 
 the ground, similar to those used by farmers for storing potatoes during the 
 winter. In these some brushwood is burned, probably to fill the pit with 
 empyreumatic vapours, whereby the possibility of fermentation and decay of 
 the madder is prevented. The roots are then covered over with soil, and left 
 in the pits for some five or six months. After this lapse of time the madder is 
 found to have lost all its sugar and the other inert vegetable matters it 
 contains. It is next dried in the sun, and after this treatment is known as 
 Marina. Its tinctorial power is greatly enhanced by this process. In Alsace 
 and Zealand the root is dried artificially in kilns. In Zealand peat is gene- 
 rally used as fuel, and in the kilns the smoke and gaseous products of com- 
 bustion are let pass through and over the roots. In the more improved 
 establishments steam or hot air is employed with advantage. By this drying 
 the root is enabled to keep, and rendered more marketable. A second drying 
 has to be performed to fit it for grinding. 
 
 The fresh root contains from 70 to 80 per cent of water. That from Alsace 
 and Zealand, and indeed from any clay soil, is rich in sugar and other 
 substances, which render the drying more difficult. After drying, the root 
 still retains 15 to 19 per cent of water, which can only be got rid of by 
 exposure for twenty-four to thirty-six hours to a temperature of 50 to 6o° C. 
 
 A higher heat is injurious, and even at this temperature combustion some- 
 times ensues. After drying, the roots are beaten with thrashing-machines, to 
 remove sand, clay, and rootlets. The latter, along with some of the bark of 
 the roots, are separated by means of sieves, and sold for dyeing. The 
 Levantine, Spanish, and Neapolitan roots generally find their way to Avignon, 
 to be there ground up. These contain only 12 to 14 per cent of water, and 
 are easily dried. The alizaris (unground roots) are met with in commerce 
 packed in bags or casks, weighing, for the countries, above 9 to 10 cwts. The 
 Vaucluse alizaris are packed in coarse canvass bags, and weigh from 1} to 2 
 cwts. Zealand roots were formerly very rarely met with unground. The 
 result was that it was rare to find even 25 casks (weighing about 12 cwts. each) 
 of ground Dutch madder exactly alike. A recent improvement is that in 
 Zealand, as well as in the Vaucluse, large works have been established, whose 
 owners buy the roots irom the smali growers. Hence a quite uniform product 
 is obtained in quantity. A very large proportion, both here and in the 
 Vaucluse, is at once converted into garancine and other preparations. When 
 the dry root has been stored a second time it is broken up and ground by 
 edge-stones. The stones used in France are made of a kind of hard lime- 
 stone. The excellent stone got from Belgium has been found to answer well. 
 When ground the madder is carefully mixed, and packed in strong casks. 
 Those from Zealand contain about 12 to 14 cwts., and those from Vaucluse 
 20 to 22 cwts. In Zealand adulteration is repressed by heavy penalties, and 
 the maufactories are placed under proper inspect ion, so as to secure the purity 
 of the article. This regulation has tended to support the Zealand madder in its 
 severe competition with that of Avignon, where adulteration is not uncommon, 
 
MADDER. 
 
 233 
 
 as admitted by French authorities. There exists a considerable difference 
 between the fresh root and the commercial madder, both in appearance and 
 properties. When the recent root is squeezed an acid yellow liquid oozes out 
 which turns red on exposure to the air. This fluid, when applied to cotton 
 prepared with acetate of alumina, yields a bright red dye, which turns a dull 
 rose-colour when soaped. The entire fresh root and its different parts yield 
 duller and more fugitive shades than does the dried root. When a thin section 
 of the fresh root is viewed under the microscope, not a trace of any separate 
 colouring matter is seen. According to the researches of M. Decaisne the 
 cells of the fresh root are filled with a yellow liquid, the deeper in colour as 
 the plant is more mature. This liquid becomes converted into an insoluble 
 red principle on contact with the air. It is a strange fact that the fresh madder 
 has never been the subject of any other than chemico-microscopic research, 
 on a very limited scale. After being ground the constituents of the root un- 
 dergo important modifications, which go on even after it has been strongly 
 compressed into the casks. We shall return to this subject after having con- 
 sidered the composition of madder.* 
 
 Kcechlin found in 100 parts dry commercial madderf 55 parts of matter 
 soluble in cold water; 3 parts soluble in boiling water, including the colouring 
 matter ; 1*5 soluble in alcohol ; and 38 insoluble in the above liquids. 
 
 a. Substances Soluble in Cold Water. — 
 
 1. Glucose, or at least a saccharine substance capable of fermentation, 
 
 and of yielding an abundant precipitate with Fehling's test. 
 
 2. Cane-sugar, found at least in the Zealand and Alsace varieties. The 
 
 amount varies with the age of the root and the circumstances of its 
 growth, but cannot be estimated at less than from 13 to 16 per cent. 
 Part of the glucose pre-exists in the root, but part, as is evident from 
 the researches of Dr. Schunck, is formed by the splitting up of the 
 glucosides which the root contains. 
 Neither of these sugars is of any use in dyeing. Both are sometimes 
 
 utilised in the shape of alcohol, formed during the manufacture of flowers of 
 
 madder. 
 
 3. Gum and Mucilage. — The latter appears to be a pectate of potash. The 
 
 cold aqueous infusion of ground madder from Zealand and Alsace 
 often becomes a complete jelly from the abundance of this substance. 
 
 4. The aqueous solution of madder, like that of other vegetables, 
 
 contains albumen. 
 
 5. A peculiar nitrogenous principle precipitable by alcohol and acting the 
 
 part of a ferment. It breaks up the colouring glucosides, and con- 
 verts pectin into pectic acid (erythrozym). 
 
 * In order to decide the question as to the effe<5t of heat in drying madder in Zealand, a 
 quantity of fresh root — about 1 kilo.— was carefully cleansed from earth, and placed, unbroken, 
 under a bell-glass over sulphuric acid. The air of the glass was exhausted, and the pump 
 worked daily for half an hour, to remove any air or vapour given off from the roots. After 
 about three weeks the roots were quite dry, and, on being ground up, the madder was not 
 found to differ from that prepared in the ordinary way. Its colour was paler, but its tinctorial 
 power was at least equal. 
 
 t Madder is very hygroscopic, and may contain 17 per cent of water without feeling damp. 
 

 234 
 
 DYEING AND CALICO PRINTING. 
 
 6. Pcctose. — According to Schi'itzenberger, madder contains pedtose, which 
 
 he infers from the fact that on adding an aqueous solution of madder 
 to solutions of pe&in, the latter were speedily gelatinised. 
 
 7. Chlovogenin (Schunck), called rubichloric acid by Rochleder. 
 
 This substance is one of the immediate principles of madder and of a few 
 other plants. When boiled with weak mineral acids it is decomposed, yielding 
 a sap-green insoluble matter. 
 
 8. Alkaline Tartrates, Malates, and Citrates, according to Rochleder are 
 
 found in the cold aqueous extract, though the Levant madders were 
 asserted to contain citrates only. Dr. Schunck has never met with 
 either tartaric, citric, or malic acid in madder, but with abundance 
 of oxalic in their stead. He very justly remarks that in the older 
 analyses of vegetable matters non-crystallisable acid syrups were 
 commonly set down as "malic acid." 
 
 9. We find, further, nondescript extractive matters with colouring 
 
 glucosides, of which we shall treat below. 
 
 10. Alkaline sulphates, phosphates, and chlorides. 
 
 b. Substances Soluble in Boiling Water and in Alcohol. — 
 These comprise chiefly the colouring matters and resins, of which we shall 
 speak subsequently. 
 
 The immediate principles insoluble in water and alcohol comprise 32 to 40 
 per cent of woody fibre, deduction having been made for the mineral con- 
 stituents. This insoluble portion is made up of cellulose, free pe<tic 
 acid, pe<5tose, pectate, oxalate, carbonate, and phosphate of lime ; phosphate 
 of magnesia with silica, alumina, and oxide of iron. The study of the ash, 
 both as to its quality and quantity, is of great importance, since it not only 
 affords the means of detecting a certain class of adulterations, but bears upon 
 the results obtained in dyeing with different kinds of madder. The ash, which 
 is not easily obtained quite free from traces of organic matter, contains the 
 mineral salts naturally present in the plant, and those formed by the decom- 
 position of the salts of organic acids. Among the latter occur, therefore, 
 carbonates of soda, potash, and lime. The composition of the ash varies, 
 as might be expected, with the composition of the soil in which the madder 
 is grown. The percentage differs also greatly. Chevreul found in 100 parts 
 of Levant madder* 9/8 of ash, and in that of Alsace 9-5 to 12 and 13. 
 According to Schlumberger, Avignon madder yields on an average 8*o8 
 per cent of ash, and that of Alsace 7-20. Persoz (senior) found the 
 following percentages, noting expressly that he employed pure nitrate 
 of ammonia in order to burn off the last traces of carbon : — Alizari 
 from Avignon, 8 - i to 8 - 03 ; racine from Alsace, 6 - 3 to 605 ; pure palud madder 
 from Vaucluse, 9-6 to 1072 ; rosee from the same district, 8-4 to 8-85. Alsace 
 madder, 7-9 to 7-02. Girardin states that several experiments made by him 
 with pure madder yielded only 5 per cent of ash. Notwithstanding this 
 author's great authority, it is undeniable that his statement only refers to the 
 
 * The question arises whether this has heen madder, or racine. No roots are ground 
 the Levant or Barbary, and the root only comes into the market as "alizari,'.' or "racine 
 " Marena" is only occasionally brought to Europe. 
 
MADDER. 235 
 
 minimum of ash found in this substance. In some low-priced madders, con- 
 taminated with the earth and sand in which the roots have grown, the ash 
 amounts occasionally to 50 per cent. Dried Zealand madder, very carefully 
 incinerated, gave 7*20 to 9-5 ash on an average of some 50 estimations. The 
 composition of the ash of madder varies. Schlumberger found in 100 parts — 
 
 Salts of potassium 4*06 
 
 Silica 0-15 
 
 Phosphate of lime and alumina o - 8o 
 
 Carbonate of lime 3-60 
 
 Loss 0-15 
 
 Total ash 876 
 
 The same chemist found in 100 parts of Alsace madder — 
 
 Salts soluble in water 4-23 
 
 Silica 0-65 
 
 Alumina and phosphate of lime 1-33 
 
 Carbonate of lime 0*87 
 
 Loss 0-12 
 
 Total ash 7-20 
 
 100 parts of Avignon madder yield 5*72 parts carbonate of lime, of which 
 2-7 pre-exist as bicarbonate, while the rest is formed by the ignition of organic 
 salts of lime from which latter source the small quantity of carbonate of lime 
 met with in the ash of the Alsace madder is exclusively derived. 
 
 The results of the researches made by Kuhlmann, Bucholz, and John, all 
 previous to the year 1826, are in some respedls noteworthy, and may be briefly 
 summarised here. Madder, according to Kuhlmann, contains — 
 
 1. A yellowish-brown colouring matter soluble in cold water. 
 
 2. A red colouring matter soluble in hot water. 
 
 3. Woody fibre. 
 
 4. Vegetable acid. 
 
 5. Mucilage. 
 
 6. Vegeto-animal matter. 
 
 7. Gum. 
 
 8. Sugar. 
 
 9. Bitter principle. 
 
 10. Odoriferous resin. 
 
 11. Ash, viz. — 
 
 Carbonate of potassa o'OoS 
 
 Sulphate of potassa 0-032 
 
 Phosphate of potassa 0-037 
 
 Chloride of potassium 0-703 
 
 Carbonate of lime 0-467 
 
 Phosphate of lime 0-082 
 
 Silica 0-020 
 
 Loss 0-031 
 
 1-380 
 
— HBa— km 
 
 236 DYEING AND CALICO PRINTING. 
 
 Bucholz found in 100 parts of air-dried madder — 
 
 Red extractive matter 39"00 
 
 Brownish red matter soluble in alkalies and ) 
 
 alcohol I * 
 
 Acrid extractive matter o - o6 
 
 Red fatty resin 1*02 
 
 Brownish red gum 9/00 
 
 Woody fibre 22*05 
 
 Matter soluble in caustic potash 4*06 
 
 Vegetable salts of lime 1*08 
 
 Moisture 12*00 
 
 Loss .. 7*04 
 
 ioo*oo 
 According to John, gg parts contain — 
 
 Brown-red wax-like substance ..'"'.. .. i*oo 
 
 Red resin 3*00 
 
 Red extractive matter 12*00 
 
 Oxidised extractive 5*00 
 
 Brown gum 8*oo 
 
 Woody fibre 42*05 
 
 Acetates of potassa and lime 8*oo 
 
 Phosphate, sulphate, and chloride ofi 
 
 potassium f ' 
 
 Phosphate of lime and magnesia 7*05 
 
 Silica 1*05 
 
 Oxide of iron 0*05 
 
 The varieties of madder from different localities behave in the dye-beck in 
 a perceptibly different manner. This appears partly due to the special nature 
 of the colouring matter contained in each variety. It is, therefore, useful to 
 study each kind separately. Since there is on this subject wide divergence 
 of opinion both among scientific and practical men, we premise the following 
 principles : — 1. The fresh root contains its tinctorial principles in another 
 form from the ground madder which has been kept for some months. In the! 
 former state the colouring matters are in some combination which renders 
 them soluble in water, but the moment the juice of the root is in contact; with| 
 the air this state is modified. 2. The soluble combination of the madder- 
 pigments is of the same kind as those which chemists know under the name] 
 of glucosides. The experiments made by E. Koechlin, Decaisne, WattJ 
 Robiquet, Colin, Kuhlmann, Higgin, and Runge, fully prove the existence of] 
 soluble colourable* matters in the fresh root as well as in the powder met! 
 with in commerce, though the quantity decreases with the increasing age ofl 
 the madder. + The researches of these chemists throw no light upon the precise! 
 nature of these substances. We shall review the labours of the authorities! 
 named, and compare them with the results of Schunck and Rochleder. WattJ 
 while operating upon Zealand madder, observed that cold water takes upl 
 
 * Such as are under certain circumstances capable of forming pigments and dyes. 
 
 t No satisfactory explanation has been given for the well known fact that madder impro' 
 in the cask. This is most marked in Zealand madder, which reaches its perfection af 
 twenty months, and is still excellent after thirty-two. Avignon madder is spoiled much earli 
 
MADDER. 
 
 237 
 
 from that substance a certain amount of colouring principle. Recent Zealand 
 i madder-root, provided it be unbroken, can be washed with cold water without 
 J the slightest loss of colouring matter. The experiment was made upon 
 2 kilos, of fresh root, carefully cleaned from adhering earth with a sponge. 
 When an aqueous infusion of madder is slowly evaporated in an open vessel 
 I exposed to the air there is formed on the surface of the liquid a pellicle, which 
 soon sinks to the bottom, and is succeeded by the appearance of another, 
 I which goes on until the whole is evaporated to dryness. The extract thus 
 formed is only in part soluble in water. From the experiments made by 
 Robiquet and Colin while preparing pure alizarin from Alsace madder, it 
 follows that in this madder at least a portion of the alizarin is present in a 
 state soluble in water.* The quality of the water may seriously affeft the results 
 of such experiments. Experiments instituted some years ago with fresh Zealand 
 madder and Zealand racine in sufficient quantity (5 kilos, of each) show 
 that cold water does not appear to extract any of the tin&orial matters. With 
 ground madder it is different. On drying the substances previously experi- 
 mented with very carefully, powdering and dyeing with them against standard 
 samples of madder of known tindorial value, no inferiority was found in the 
 roots. On submitting them to analysis, the quantity of alizarin found did 
 not differ from that extracted from roots treated as usual. The above- 
 mentioned chemists mixed 1 part of madder with 3 parts of water, filtered 
 and pressed the substance upon a piece of cloth, and obtained a red-brown 
 liquid, which in about ten minutes was converted into a jelly. This was 
 found to be a mixture of pedlic acid and gelatin, which had become 
 insoluble. As far back as 1823, Kuhlmann observed that madder contains a 
 yellow colouring matter, very soluble in water, which he named Xanthin. 
 He obtained this xanthin by exhausting madder with boiling alcohol, 
 evaporating the solution to dryness, and taking up the dry residue with water, 
 which dissolves the xanthin, and leaves any alizarin that may have been 
 extracted undissolved. The fluid is first filtered, then acetate of lead is 
 added, whereby a brownish matter is precipitated. This is removed by 
 filtration, and to the filtrate baryta-water is added, whereby a precipitate is 
 formed, containing xanthin combined with oxide of lead. This precipitate 
 is thoroughly washed, and, after having been suspended in pure water, is 
 decomposed with very dilute sulphuric acid. The sulphates of lead and 
 baryta having been removed, the liquid is evaporated to dryness, the dry 
 residue taken up with alcohol, and again evaporated. The xanthin is then 
 left as a viscid, bright orange-coloured substance readily soluble in water. It 
 has a sweetish bitter taste, and is soluble in alcohol, but insoluble in ether. 
 Alkalies turn it red. Neither the neutral nor the basic acetate of lead gives 
 a precipitate with this substance. It dyes mordanted cotton a bright orange. 
 It is decomposed by strong sulphuric acid, yielding chlorrubin, so that this 
 substance is a mixture of at least two substances as well as glucose. Zealand 
 Alsace, and Avignon madder contain far more xanthin than the madder 
 from the Levant and Barbary. 
 
 Runge obtained a yellow soluble substance by exhausting Zealand madder 
 with sixteen times its weight of water, and precipitating the solution with 
 
 [ " Annales de Chimie et de Phys.," t. xxxiv., p. 225 ; and " Bulletin de la Soc. Indust. de 
 Mulhouse," t. i., p. 10S. 1828. . 
 
■■■ 
 
 238 
 
 DYEING AND CALICO PRINTING. 
 
 lime water. This precipitate is decomposed with acetic acid, and the solution 
 boiled with wool mordanted in alum to remove purpurin. The solution is 
 evaporated to dryness, taken up with alcohol, and again precipitated with an 
 alcoholic solution of acetate of lead. The precipitate thus obtained is 
 washed with alcohol, and decomposed with sulphuretted hydrogen.* 
 
 Higg ; n exhausts madder with boiling water, precipitates the matters 
 sparingly soluble in water with very dilute sulphuric acid, saturates with 
 carbonate of soda, and afterwards digests the fluid with hydrate of alumina, 
 in order to separate alizarin. Baryta water is next added, and afterwards 
 subacetate of lead. The precipitate is well washed and decomposed with 
 sulphuretted hydrogen. The product thus obtained still contains chlorogenin, 
 since on being boiled with acids a green precipitate ensues. 
 
 According to Schunck, the aqueous extract of madder, made either with 
 cold or tepid water undergoes spontaneous decomposition, either with or 
 without access of air. A flocculent yellow precipitate is formed, which 
 contains all the colouring matter of the infusion. Schunck ascribes the bitter 
 taste, and the tinctorial properties of the extract, to a substance which he 
 names Rubian, and considers the xanthin of Kuhlmann, Runge, and Higgins 
 to be a mixture of rubian, chlorogenin, and glucose. Rubian, properly pre- 
 pared, is a hard, amorphous, brittle substance, glossy when in thin laminae. 
 Its colour is deep yellow, or brown when seen in large masses. It is per- 
 manent in the air, easily soluble in water, sparingly in alcohol, and insoluble 
 in ether. It has an intensely bitter taste. The aqueous solution is pre- 
 cipitated only with subacetate of lead. With concentrated sulphuric acid rubian 
 yields a blood-red solution, decomposable by heat. Nitric acid does not affect 
 cold solutions of rubian, but, on boiling, phthalic acid is formed. Normal 
 phosphoric acid and the organic acids are without any action upon rubian, 
 even at the boiling-point. Soda converts the yellow solution to a blood-red, 
 which, on boiling, becomes purple. Acids then precipitate from the solution 
 a reddish-orange substance, and the liquid becomes colourless. At a higher 
 temperature the glucoside ■which forms the rubian is split up. Ammonia also 
 modifies the yellow solution to blood-red, but no further change ensues on 
 boiling. Lime and baryta water throw down rubian as a deep red substance, 
 soluble in water. Magnesia converts the yellow solution of rubian to a deep 
 red, the alkaline earth becoming dissolved. Carbonates of lime and baryta 
 have no action ; alumina and the hydrated peroxide of iron and oxide of 
 copper throw down rubian completely from its solutions. In presence of an 
 alkali, rubian reduces the salts of gold, but salts of silver and copper are not 
 acted upon under the same conditions. Rubian fuses when heated, and burns 
 on ignition, leaving from 6 to 8 per cent of ash, consisting of carbonate of lime. 
 If heated to 130° C. in a tube, it yields orange vapours, composed chiefly of 
 alizarin. When rubian is boiled with dilute hydrochloric or sulphuric acid it 
 yields, on cooling, a flocculent orange matter, insoluble in these acids. In the 
 liquid there remains a kind of sugar capable of fermentation and of reducing 
 alkaline solutions of copper. Rubian undergoes a similar decomposition by 
 the action of a peculiar nitrogenous compound which exists in madder, and 
 
 * It should be kept in view that too many of those who have experimented with mad 
 have entirely forgotton two essential points :— To ascertain the time that the sample 
 been in cask, and the precise locality and manufactorylrom which it originated. 
 
RUB I AN. 
 
 239 
 
 is called erythrozym.* This ferment may be obtained by the addition of 
 alcohol to an aqueous infusion of madder, when a curdy precipitate is formed. 
 If this is added to a solution of rubian, the latter in the course of a few hours 
 becomes a bright brown jelly, containing the tinctorial principles in an insoluble 
 state. Rubian is very difficult to obtain pure, being very liable to decom- 
 position and not precipitable by any metallic salt, except the subacetate of 
 lead. The separation of rubian from chlorogenin requires very nice manipula- 
 tions. To effect this separation Schunck makes use of the great affinity of 
 rubian for porous bodies, especially animal charcoal. He digests a hot decoction 
 of madder with animal charcoal, and washes the latter on a filter with cold 
 water until a small quantity of the washings, when boiled with hydrochloric 
 acid, ceases to yield a greenish colouration. Thus the chlorogenin is 
 removed. The charcoal is next exhausted with boiling alcohol, which extracts 
 the rubian. The alcoholic solution is evaporated to dryness, taken up with 
 water, again treated with animal charcoal, and the latter again exhausted with 
 alcohol. 
 
 This treatment is repeated until the chlorogenin is entirely removed. The 
 alcoholic solution is finally evaporated to dryness, taken up with water, and this 
 aqueous solution is first treated with a solution of neutral acetate of lead, 
 which precipitates any impurity. It is filtered, and then precipitated with 
 basic acetate of lead. The precipitate formed is decomposed with sulphuretted 
 hydrogen or dilute sulphuric acid, and after removal of the lead compound 
 rubian is left dissolved in the water. The substance in this state still retains 
 mineral matter, and is therefore not quite pure. Nevertheless, we may draw 
 conclusions regarding the tinctorial matter pre-existent in the madder root 
 during its growth. Rubian is a glucoside, or perhaps a mixture of glucosides, 
 capable of being decomposed by acids, alkalies, and ferments into colouring 
 matters and sugar. Since Dr. Schunck's analysis shows the formula to be 
 CigHigOs, the following equation represents the reaction which takes place : — 
 
 CjgHjeOs + H 2 = C IO H 6 C>3 + C 6 H I2 6 
 
 Rubian. Alizarin. Glucose. 
 
 We shall presently see that the constitution of rubian is scarcely so simple. It 
 probably contains several glucosides capable of yielding alizarin and pseudo- 
 purpurin, &c. The composition of all these colouring matters approaches 
 closely that of alizarin. Schunck has never found purpurin among the 
 products of decomposition of rubian, whether this was affected by an acid, an 
 alkali, or a ferment. He always, hewever, found a yellow crystalline colouring 
 matter, first discovered by Runge, and named by him " madder orange." The 
 nature of this colouring matter varies according to the agent employed, or 
 rather, acids give rise to one substance, alkalies to another, and ferments to 
 a third. These three substances, though essentially distinct, have some 
 properties in common. Two of them, rubiacin and rubiadin, can easily be 
 identified by their reactions. Rochleder's researches are chiefly valuable from 
 the fact that he has succeeded in isolating the alizarin-glucoside in a crystalline 
 state, and has named it ruberythric acid. It occurs mixed up with rubian. 
 
 * The nitrogenous principles met with in madder are extremely prone to change, and are in 
 this respect as difficult to study and to obtain in a pure state as some of the biliary principles. 
 It is always the molecule en mouvement, and hence its protean properties. 
 

 240 
 
 DYEING AND CALICO PRINTING. 
 
 A hot decoction of sliced Levant madder-root is treated successively with 
 neutral and basic acetate of lead. The second precipitate, after being tho- 
 roughly washed, is decomposed with sulphuretted hydrogen. The sulphide of 
 lead is well washed with cold water, which removes phosphoric and rubichloric 
 acids, leaving almost the whole of the ruberythric acid along with the sulphide 
 of lead. The lead compound is next thoroughly exhausted with boiling 
 alcohol, and the solution thus obtained concentrated by evaporation on the 
 water-bath. The residue is taken up with water ; a little baryta-water is 
 added, and the precipitate thus produced is filtered off. More baryta-water is 
 added, in order to throw down the ruberythric acid as a deep cherry-red floc- 
 culent ruberythrate of baryta. This is dissolved in dilute acetic acid, the 
 solution nearly neutralised with ammonia, and then precipitated with basic 
 acetate of lead. The cinnabar-red precipitate thus obtained is suspended in 
 alcohol, decomposed with sulphuretted hydrogen, boiled, and filtered hot. On 
 cooling, ruberythric acid is deposited in bright yellow, silky, prismatic crystals. 
 It is very soluble in ether, alcohol, and hot water, but sparingly in cold water. 
 It bears, in many respects, a great likeness to rubian. By mineral acids it is 
 split up into sugar and alizarin. 
 
 The researches of Kopp on the colourable glucosides are very interesting.* 
 He treated Alsace madder, about six months old, with a saturated solution of 
 sulphurous acid. By this means the peculiar action of the ferment present in 
 the madder is arrested, and the colouring matters present are eliminated in a 
 soluble condition. The filtrate is yellow, and on the addition of 2 to 3 per 
 cent of hydrochloric acid, and heating to 6o° C, a flocculent red matter is 
 thrown down not containing a trace of alizarin. On raising the temperature 
 to the boiling-point alizarin is thrown down mixed with chlorrubin. The 
 alizaric glucoside is therefore more stable than the other glucosides. The 
 aqueous solution of madder, treated with dilute sulphurous acid, shows, after 
 pressure and filtration, the following properties : — The concentrated liquid is 
 deep orange, with a brownish shade. The taste is faintly acid, mixed with a 
 sweetish bitter. Notwithstanding the smell of the sulphurous acid, the cha- 
 racteristic odour of madder is quite distinct. In closed vessels this solution 
 remains unaltered for a long time. Sometimes a brownish, light, flocculent 
 deposit forms. If the solution of sulphurous acid employed is contaminated 
 with hydrochloric acid there is deposited, in five to eight days, a semi- 
 crystalline mass of purpurin, of a bright vermillion-red. Since this deposit 
 is very heavy, it can easily be removed by decantation. If the fluid containing 
 sulphurous acid is exposed to the air it loses its odour, and grows turbid. A 
 pulverulent greyish-black substance is deposited, and the liquid becomes dis- 
 coloured. Decomposition sets in, and when ammonia is added there is no 
 longer a beautiful violet-red, but a dirty muddy appearance. This solution of 
 madder in sulphurous acid behaves with reagents as follows : — With potash, 
 soda, and ammonia, no precipitate, but a violet-red colouration with a yellowish 
 tinge. If the alkaline solutions are very concentrated a precipitate is formed 
 on boiling. The liquid retains its original colour as produced by the addition 
 of an alkali, and a portion of the precipitate is re-dissolved on the addition of 
 water. Nothing is at first produced by the addition of hydrochloric acid, but 
 
 * E. Kopp, " Repertoire rle Chimie Appliquee," tome iii., p. 85, and " Bulletin de la Societ6 
 Industrielle," tome xxxi., p. 145. 
 
RUDIAN. 
 
 241 
 
 after some time a yellowish-red or brownish precipitate of purpurin is formed. 
 The same happens when nitric acid is substituted for hydrochloric acid. In 
 both instances this fluid remains orange-yellow. Oxalic acid produces no 
 immediate change, but after a time there is formed a pale yellow flocculent 
 precipitate containing oxalate of lime. The colour of the fluid is not altered. 
 No reaction is produced by the addition of alkaline chlorides, or of the 
 chlorides of the alkaline earths. Carbonate of soda gives no precipitation, 
 but colours the fluid purple. Lime-water yields immediately a brownish- 
 crimson precipitate, and the colour of the liquid turns a reddish-violet. If the 
 precipitate is filtered off, and heat applied, another precipitate of a rose-red is 
 produced. Solution of alum produces no change at first, but after a time a 
 brilliant vermillion precipitate is produced, the supernatant liquor remaining a 
 yellowish-red. If a large excess of solution of alum is added, and a solution 
 of carbonate of soda or lime-water immediately after, a rose-red precipitate is 
 obtained, which, when dry, exhibits a very pure rose-colour, especially if lime- 
 water has been employed. The acetate and the hyposulphite of alumina give 
 similar reactions. The precipitation of this alum-lake is promoted by heat. 
 Its shade depends very much upon the relative proportions of the ingredients, 
 and upon the concentration of the madder-liquor. With hypochlorite of lime 
 the liquid is bleached to a yellowish colour, and a light flocculent precipitate 
 is deposited. A solution of protosulphate of iron gives a deep brown preci- 
 pitate, the liquid assuming a deep — somewhat inky — colour. With perchloride 
 of iron no immediate precipitate is formed; the liquid turns a deep brownish- 
 yellow, and after a time a brownish-black precipitate is deposited. Perchloride 
 of tin gives an orange-yellow precipitate. With acetate of lead in moderate 
 quantity there is formed a chamois-coloured precipitate, the liquid retaining 
 its orange-yellow colour. If the precipitate first formed is removed, and a 
 further quantity of the same reagent is added, a yellowish-red precipitate is 
 produced, and the supernatant liquid retains only a slight yellowish colour. 
 On the addition of ammonia to this liquid a fine rose-red precipitate is pro- 
 duced. Corrosive sublimate gives a flesh-coloured precipitate, whilst the 
 liquid remains yellow. If the mercuric salt has been previously acidified with 
 hydrochloric acid no immediate precipitate is formed, but after a time an 
 orange-red precipitate is deposited, which is almost entirely soluble in boiling 
 water. 
 
 Secondary colouring matters, either insoluble or but very sparingly soluble 
 in water, are derived from the decomposition of the above-mentioned sub- 
 stances. On this subject there has been much controversy; for while no one 
 denies the existence of alizarin, some assume the presence of one or more 
 distinct tinctorial substances, whilst others hold these to be merely alizarin 
 in a more or less impure state. This last view gained strength from the fad: 
 that the physical, chemical, and tinctorial properties of alizarin are very 
 readily modified and masked by the presence of small quantities of heteroge- 
 neous matter. Thus, as long as alizarin retains traces of a resinous fatty 
 matter which clings to it very persistently, it yields in alcohol a brown solution, 
 and cannot be obtained in well-defined crystals. When pure it dissolves in 
 alcohol with an orange colour, and forms long needle-shaped crystals. The 
 large number of colouring matters which, according to Schunck, are derived 
 from rubian, did not appear to many investigators of this subject sufficiently 
 well defined to be accepted without some hesitation. 
 
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 BBBBBB 
 
 242 
 
 DYEING AND CALICO PRINTING. 
 
 Since the researches of Persoz, Gautier de Claubry, Runge, and others, the 
 existence of another red pigment, purpurin, has been admitted. It differs 
 from alizarin by the purple colour of its alkaline solution, whilst alizarin 
 yields violet-blue solutions. Kopp subsequently succeeded in producing, on a 
 manufacturing scale, a preparation containing no alizarin, and exhibiting all 
 the characters of purpurin. One kilo, of this product represents about 
 60 kilos, of Alsace madder. It was carefully investigated by Schiffert and 
 Schiitzenberger. They considered the existence of the following colouring 
 matters as decided: — (1), alizarin; (2), purpurin; (3), pseudopurpurin — 
 these three are either red or orange, and yield red shades with aluminous 
 mordants; (4), an orange matter which likewise yields, with aluminous mor- 
 dants, a red shade; (5), a yellow matter, xanthopurpurin (not to be confounded 
 with Kuhlmann's xanlhin), yielding, with aluminous mordants, yellow shades. 
 
 The existence of the three last colours mentioned by Schiitzenberger is 
 considered by Schunck more than doubtful. They are either mixtures or are 
 identical with substances previously known. The yellow colour has exactly 
 the same percentage composition as rubiacin. The latter is distinguished 
 from all the other madder colours by dissolving in per-salts of iron with a 
 purple or brownish-red colour ; this simple test would have decided the 
 identity or distinction of the two bodies. The practice of giving little more 
 than analyses of new substances without any account of their characteristic 
 reactions is highly objectionable. 
 
 Alizarin, or lizaric acid, is the most important and the most valuable 
 colouring matter contained in madder. It is the only one which yields fast 
 dyes capable of resisting the operation of cleansing. By a series of experi- 
 ments made by Schiitzenberger with variously-mordanted cloths, submitted 
 afterwards to dye-becks containing madder and its commercial preparations, 
 
 it has been fully proved that in these dyed shades — Turkey-red included 
 
 alizarin alone is present. Hence it is inferred that alizarin pre-exists in the 
 madder-root, and is not a product of any subsequent decomposition. 
 
 Alizarin is readily obtained in crystals, both by sublimation and by the 
 evaporation of its solutions. It is procured as hydrate by the slow evapora- 
 tion of its ethereal solution. In this state alizarin has the appearance of 
 micaceous plates of a golden-yellow lustre, not unlike mosaic gold. At ioo° C. 
 it loses 3 equivalents of water. The anhydrous crystals exhibit brilliant 
 prismatic needles of a red tint, verging upon yellow. These crystals are best 
 obtained by sublimation at 240 C, or by deposition from strong boiling 
 alcohol not containing more than 14 per cent of water. This process only yields 
 good crystals with alizarin that has once, at least, been purified by sublima- 
 tion. It can also be obtained by crystallisation from water, in a sealed tube 
 at 250 or 280 C, or, better still, by the use of a mixture of 9 parts of water 
 and 1 part of alcohol. 
 
 Alizarin fuses at 215 C, and sublimes between 215 and 240 , but if kept 
 for a long time at ioo° C. it slowly evaporates, more readily if placed in a 
 current of water or of steam. If it is desired to sublime alizarin without 
 decomposition, it should be heated in small quantities only. The best method J 
 of subliming alizarin, from impure alizarin, alcoholic madder extract, extract i 
 of garancin, or any other substance containing alizarin, is to place the sub- 
 Stance to be operated upon at the bottom of a small porcelain capsule capable 
 
MADDER. 
 
 243 
 
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 244 
 
 DYEING AND CALICO PRINTING. 
 
 of containing 50 grms. A few decigrms. of material are sufficient for the 
 experiment. A piece of clean white filtering-paper is placed on the top of the 
 capsule, which is next covered with its lid and heated on the sand-bath to 
 250° C. After the lapse of half an hour the interior of the capsule will be 
 found lined with long, beautiful needles. At the bottom there remains a 
 porous, bulky, carbonaceous substance, containing hardly a trace of alizarin, 
 when pure alizarin has been experimented with. When alcoholic extract of 
 madder or garancin has been submitted to sublimation the alizarin is often 
 soiled by empyreumatic substances, and requires to be re-sublimed. The 
 colour exhibited by alizarin varies according to the conditions under which it 
 has been obtained. It is sometimes a dark red substance, usually rather 
 orange, but sometimes yellow, especially if it is crystallised from an acid 
 solution, — as, for instance, when glacial acetic acid has been applied. Pure 
 cold water only dissolves an insignificant trace of alizarin, but if the water 
 contains any alkaline matter it becomes yellowish or orange by a trace of 
 alizarin. According to Plessy and Schiitzenberger, 100 parts of water, at 
 ioo° C, dissolve 0*034 part of alizarin ; at 150° C, 0^03 5 ; at 200 C, 0*82; 
 at 225 C, 170 parts; at 250 C, 3-16. Up to 200 C, therefore, the 
 solubility increases slowly, but becomes far greater on approaching the 
 subliming point of alizarin. The solubility of alizarin in alcohol is not 
 perfectly determined. At the ordinary temperature of the air it is more soluble 
 in alcohol than in water. When pure, a boiling alcoholic solution of alizarin 
 exhibits an orange-yellow colour, and on cooling deposits long needle-shaped 
 crystals. Alizarin is readily soluble, especially with the aid of heat, in ether, 
 wood-spirit, benzol, oils of tar, naphtha, and petroleum, spirits of turpentine, 
 sulphide of carbon, glycerine, chloroform, and acetic acid. The hot saturated 
 solutions of some of these deposit alizarin in crystals on cooling. An aqueous 
 solution of alum does not, when cold, dissolve any alizarin. It dissolves to 
 some extent in a hot solution, but is re-deposited on cooling. Strong sulphuric 
 acid dissolves alizarin without decomposition or change. Water precipitates 
 the colouring matter from this solution unaltered, in the shape of an orange 
 flocculent precipitate. The solution of alizarin in sulphuric acid is not 
 affected by a temperature of 200 C. As regards the composition of alizarin 
 and the formulae assigned it various views prevail. That given by Dr. 
 Schunck, Ci 4 Hi O 4 , agrees best with the analysis of pure specimens, and is 
 confirmed by the experiments of Graebe and Liebermann on the artificial 
 formation of alizarin. Schunck deduced his formula from the examination of 
 rubianic acid, the glucoside of alizarin. This acid gives a potash salt crystal- 
 lising in needles, by means of which the above-mentioned chemist was enabled 
 to determine the atomic weight of the acid. It contained C 2 6i and hence 
 alizarin must have Ci 4 . Many chemists were led astray by supposing, with 
 Laurent, that there must be a close relationship in composition between 
 alizarin and naphthalin. 
 
 Alizarin is a weak acid capable of combining with bases. With alkalies it 
 yields salts readily soluble in water, sparingly soluble in alcohol, and insoluble 
 in ether. The aqueous solutions exhibit a splendid violet-blue colour. Crys- 
 tallised alizarate of soda is readily obtained by adding an alcoholic solution of 
 soda to alcohol in which alizarin is kept suspended, and immediately after 
 adding a quantity of ether to the mixture, so that it may form a separate 
 
ALIZARIN. 
 
 245 
 
 layer. The whole should then be kept for some time in a well-closed vessel, 
 and left standing undisturbed. The ether slowly mixes with the rest of the 
 fluid, and the alizarate of soda separates in the shape of needles. The alka- 
 line earths and metallic oxides yield, with alizarin, compounds insoluble in 
 water, and which are violet, red, or black. Some of these are technically 
 known as lake-colours. Those of alumina are red or rose-coloured, whilst 
 those of peroxide of iron are violet or black. The true composition of these 
 salts is but imperfectly known. The carbonates, phosphates, pyrophosphates, 
 borates, silicates, oleates, and generally all the salts capable of turning red 
 litmus-paper blue, dissolve alizarin, especially with the aid of heat, yielding 
 reddish-violet coloured solutions. Liquid ammonia acts upon alizarin in a 
 very peculiar manner, which reminds us of the behaviour of carminic acid 
 under similar circumstances. Ammonia first dissolves alizarin, yielding a 
 characteristic solution of a violet-blue colour. From this solution acids throw 
 down the alizarin unchanged, in the shape of yellow flocks. But if the solu- 
 tion is kept in a closed vessel for at least twelve hours, at a temperature of 
 ioo° C, or preserved for several weeks at common temperatures, acids no 
 longer precipitate it as before, but cause the appearance of a deep violet floc- 
 culent mass, containing the elements of alizarin and ammonia combined in so 
 stable a manner that even strong acids do not cause its decomposition. This 
 substance — called by its discoverer, Schiitzenberger, alizaramide or alizareine — 
 is formed without contact of air, and without the action of oxygen. In a wet 
 state it is of a reddish-violet colour, but when dry quite black. It is perceptibly 
 soluble in water and in alcohol, even when dilute, yielding a beautiful violet- 
 red solution. It is also soluble in ether. On evaporation of the alcoholic 
 solution it is obtained in crystals. If heated on platinum foil it burns without 
 sublimation. When boiled with caustic alkali, alizarinamide gives off ammonia, 
 but no ammonia is evolved when it is rubbed up with dry caustic lime in a 
 mortar. Cloth, previously mordanted and then dyed with this substance, 
 assumes colours somewhat similar to those yielded by madder, though less 
 rich, and accompanied by a pale violet hue. Wool is dyed by this colour of a 
 dirty lilac, without the aid of any mordant. 
 
 When alizarate of soda, in crystals, is heated in a sealed tube to 120° C, 
 along with iodide of ethyl, an ethylic derivative is obtained of a bright yellow, 
 insoluble in water and soluble in alcohol. 
 
 Chloride of benzol acts upon alizarin at 190 C. Hydrochloric acid is given 
 off, and a compound formed which is insoluble in water, soluble in alcohol, 
 but insoluble in ammonia at ordinary temperatures. When boiled with alka- 
 lies it is saponified, the result being the formation of an alkaline benzoate and 
 alizarate. 
 
 Alizarin is readily acted upon by oxidising agents. Nitric acid and per- 
 chloride of iron convert it into phthalic and oxalic acids. 
 
 The action of reducing agents upon alizarin has not been fully investigated. 
 If an alkaline solution of alizarin is heated along with aldehyd the violet 
 liquid turns orange, and on the addition of an acid a yellow flocculent preci- 
 pitate falls. Nascent hydrogen discolours the solutions of alizarin. 
 
 According to the recent researches of Graebe and Liebermann, alizarin, 
 treated with powdered zinc and hydrochloric acid, yields a hydrocarbon — 
 anthracen. Starting from this discovery the authors have devised a method 
 
^p&^^^^i BWH| 
 
 246 
 
 DYEING AND CALICO PRINTING. 
 
 for the artificial production of alizarin, to which we shall recur elsewhere 
 
 in full. 
 
 The preparation of pure alizarin from madder, on the large scale, is a tedious 
 operation. The best material to start from is an alcoholic extract of good 
 madder. Some kinds of this extract are manufactured on a large scale. 
 When properly prepared they deposit a red granular substance, very suitable 
 for the preparation of alizarin. 
 
 Another source is the " Green Alizarin" of commerce, first prepared by 
 Kopp. To obtain it on the large scale madder is mixed with ten times its 
 weight of aqueous sulphurous acid, to which a little hydrochloric acid has 
 been added to decompose the lime-salts of the madder. The mixture is 
 placed in a well-covered wooden vessel, and allowed to stand from twelve to 
 twenty-four hours, with occasional stirring. The semi-fluid mass is thrown 
 upon a filter, the vat is washed out with a little water, and the rinsings added 
 to the filter ; the liquid is allowed to run through, and the residue is strongly 
 pressed. The liquid is again put in a wooden vat. The dry pressed residue 
 is again treated with ten times its weight of sulphurous acid water, as before, 
 the filtrate and the pressings being mixed with the first liquid. This treat- 
 ment is repeated a third time, but the liquid obtained, being too weak to be 
 mixed with the preceding, is saved for the second extraction of a fresh quan- 
 tity of madder. 
 
 On adding to the sulphurous liquid about 3 to 5 per cent of sulphuric or 
 hydrochloric acid, and heating to 6o° C, an orange flocculent precipitate falls. 
 Its precipitation is complete in about thirty minutes. The deposit is separated 
 from the mother-liquor by decantation or filtration, and washed with a little 
 cold water till the washings have a faint yellow colour and display no longer 
 an acid reaction. This precipitate is purpurin, almost chemically pure. If the 
 mother-liquor is now allowed to boil for two hours the so-called green or crude 
 alizarin separates out, and is deposited in twenty-four to thirty hours as a 
 greenish-black mass. It is washed by decantation with cold water two or 
 three times. 
 
 From this so-called " green alizarin " a much purer article, " yellow 
 alizarin," is obtained by the following process : — 1 part of green alizarin is 
 boiled with 15 to 20 parts of rectified petroleum, boiling at 150 C. As soon 
 as the boiling ceases the green insoluble matter separates as a sediment. 
 After a few minutes the liquid is decanted. It contains much alizarin, part of 
 which separates out on cooling. When the temperature has fallen to about 
 ioo' C, dilute caustic soda lye is added, and the mixture well agitated. The 
 soda takes up all the alizarin, with a bluish-purple colour, whilst the petroleum 
 becomes almost colourless, and may be used again. The lye is poured into 
 dilute sulphuric acid, when alizarin separates in yellow flocks. These are 
 collected on a filter, washed till perfectly free from acid, and dried. From this 
 "yellow alizarin " pure alizarin can be prepared by sublimation. 
 
 Another suitable source for pure alizarin is cotton which has been dyed a 
 Turkey-red. Several yards of this cloth are cut up and submitted to the action 
 of alcohol, at 85 per cent, mixed with strong sulphuric acid. The fatty matter, 
 alumina, and colour are simultaneously dissolved. The liquid thus obtained 
 is very carefully neutralised with ammonia, by which the alumina is precipi- 
 tated. After filtration the filtrate is concentrated on the water-bath, and 
 
PURPURIN. 
 
 247 
 
 mixed with water. This throws down a mixture of fatty matter and tinctorial 
 substance. This precipitate is dried, and exhausted with rectified bisulphide 
 of carbon, which removes the fat. Alizarin remains behind almost pure, and 
 may be further purified, either by sublimation in a porcelain capsule, by means 
 of steam, or by the vapour of a mixture of 9 parts water and 1 part alcohol. 
 The alizarin obtained from Turkey-red is so pure that it can be sublimed 
 leaving scarcely any residue. When madder extracts have been employed as 
 the raw material the sublimed alizarin is contaminated with empyreumatic 
 products, which have to be removed by washing with cold alcohol and re- 
 crystallisation from a hot alcoholic solution. 
 
 Alizarin yields, with aluminous mordants, red and rose shades, which are 
 extremely fast, resisting the action of light, boiling soap-lyes, and even dilute 
 nitric acid. After this treatment, technically known as clearing (avivage), the 
 colour is a bright full red, or a rose with a slight bluish reflection. With iron 
 mordants alizarin yields solid blacks and violets of great beauty. The tinc- 
 torial power of pure alizarin is about ninety times greater than that of good 
 madder. To dye with pure crystalline alizarin it should be first rubbed up in 
 a mortar with some alcohol, and the mixture poured into water to which some 
 chalk has been added. No perceptible action takes place till the temperature 
 has been raised to 70 or 80° C, and the alizarin begins to dissolve. To 
 exhaust a dye-bath containing alizarin the quantity should not be very great, 
 and excess of water should be avoided ; 15 decigrms. of alizarin to 250 cubic 
 centimetres of water are sufficient. This colour-bath, into which the mor- 
 danted fabric is now plunged, should be kept at nearly the boiling-point of 
 water, by being placed upon the water-bath. The process of dyeing should 
 be continued till the liquid has been nearly evaporated to dryness. This is 
 the only satisfactory mode of testing the relative value of samples of alizarin. 
 According to the experiments of Schiitzenberger the fabric thus dyed contains 
 a lake of madder, which is red, rose, violet, or Turkey-red, according to the 
 mordant applied. 
 
 Artificial alizarin is described in the section treating of coal-tar colours. 
 
 Purpurin. 
 As early as 1828 the researches of Robiquet, Persoz, and others, pointed to 
 the presence in madder of a tinctorial principle distinct from alizarin. It was 
 first prepared by treating Avignon madder with concentrated sulphuric acid, 
 taking care to avoid too great rise of temperature during the operation. This 
 material, known in commerce as charbon sulphur ique, is then well washed 
 with water to remove acid, and next boiled for a quarter of an hour with an 
 aqueous solution of alum, containing 12 per cent of that salt. The liquid is 
 filtered while boiling, and to the filtrate 1 part of sulphuric acid is added. On 
 cooling, a red flocculent matter is thrown down along with crystals of alum. 
 It is collected on a filter, and washed with pure cold water. The quantity of 
 sulphuric acid required for the preparation of the charbon sulphurique varies 
 with the kind of madder and the scale of the operation. If a kilo, of Alsace 
 madder is taken, half that weight of sulphuric acid is sufficient. If only 25 or 
 30 grms. of the same madder are operated upon, 3 or 4 parts of acid are 
 required. The effect produced by the acid is the destruction of such mucila- 
 ginous and other matter as would render the subsequent washing of the 
 
MMMMM —— —M 
 
 248 
 
 DYEING AND CALICO PRINTING. 
 
 madder difficult and tedious; though it would be an improvement to wash 
 the madder first with water. Purpurin, as obtained by this process, still con- 
 tains alizarin, but it is distinguished from that substance by its greater solu- 
 bility in water, to which it imparts a fine rose-colour. Koechlin obtained from 
 90 parts of madder 4-5 of purpurin. Claubry and Persoz mix the madder 
 with water to a thin paste, and add, for every kilo, of dry madder, go grms. of 
 sulphuric acid. The mixture is next boiled by means of steam blown into it 
 with leaden pipes. The material is thrown on a. filter, washed with water, and 
 the residue treated first with carbonate of soda, which dissolves a red colouring 
 matter (alizarin ?), and afterwards with a boiling solution of alum. To this 
 latter solution sulphuric acid is added. A flocculent orange matter is thrown 
 down, which, after treatment with alcohol and ether, yields crystalline needles, 
 called by the above-named chemists " madder-rose." It is distinguished from 
 alizarin by its greater solubility in alum, and its insolubility in protochloride 
 of tin. 
 
 Runge and Debus boil the madder, previously washed, with alum-water, 
 filter, and let the filtrate stand for some time, to permit of the precipitation of 
 the alizarin. This is removed by a second filtration, after which the rose- 
 coloured liquid is precipitated with sulphuric acid. The flocculent matter 
 thus thrown down is washed with water, boiled in dilute hydrochloric acid, 
 and dissolved in boiling alcohol (85 per cent). On cooling, a crystalline 
 matter is precipitated, which is purified by repeated crystallisation from alcohol 
 and ether. Wolff and Strecker employ a similar mode of preparation, but 
 mix the madder previously with water, and allow it to undergo fermentations, 
 after which they wash again. Whilst thus experimenting they did not obtain 
 a trace of alizarin. Their inference that the alizarin was converted by fer- 
 mentation into purpurin has been proved to be incorrect. They propose, as a 
 method for separating alizarin from purpurin, to combine both with hydrate of 
 alumina, and to boil this lake with carbonate of soda, which dissolves pur- 
 purin. This operation may be conducted as follows: — The aqueous decoction 
 of madder is precipitated with sulphuric acid, the resulting precipitate ex- 
 tracted with boiling chloride of aluminium, and the colours thus dissolved re- 
 precipitated with hydrochloric acid. The precipitate is washed, boiled with 
 hydrate of alumina, and then boiled with a solution of carbonate of soda. 
 
 The most elegant, and at the same time most practicable, method of preparing 
 pure purpurin, free from alizarin, has been devised by Kopp, and is carried out 
 on the large scale by Schaeraff and Lauth :— 600 lbs. of ground madder are 
 allowed to steep for ten hours, in a vat containing 800 to tooo gallons of a 
 solution of sulphurous acid, and, after running off this liquid, the madder is 
 again treated with 200 to 250 gallons of the same acid solution. These liquors 
 are then mixed with 3 per cent of sulphuric acid, at sp. gr. i*6o, and the whole 
 is treated as described under the preparation of "green alizarin.'''' 
 
 Schiffer and Schiitzenberger have investigated purpurin thus prepared, and 
 pronounce it a well-defined chemical substance and a natural constituent of 
 madder, and not alizarin soiled by some foreign matter. Having operated 
 upon some 500 grms. of the commercial purpurin, they have found it to contain 
 two red colouring substances, viz., purpurin properly so-called, and pseudo- 
 purpurin, besides an orange and a yellow tinctorial body. Each of these 
 substances was obtained in a crystalline state, exhibiting distinct characters, 
 
PURPURIN. 
 
 249 
 
 and a perfectly definite elementary composition. The separation of these 
 substances is based upon their varying solubility in alcohol and benzol. The 
 yellow and orange principles arc very soluble in luke-warm alcohol at 85 per 
 cent, wherein purpurin and pseudopurpurin are nearly insoluble. The yellow 
 is soluble in benzol, in which the orange is insoluble. Purpurin is tolerably 
 soluble in boiling alcohol, from which, on cooling, it is deposited in crystals,, 
 whilst pseudopurpurin is almost insoluble in the same liquid. The yellow 
 matter, xanthopurpurin, is contained in commercial purpurin in small traces 
 only, not exceeding 1 part in 500. The orange matter and purpurin proper 
 form about one quarter of the commercial substance in equal proportions, 
 whilst the entire residue is made up of pseudopurpurin. To obtain pure purpurin 
 the easiest method is to place a little of the commercial product in a porcelain 
 capsule, and to treat it on the sand-bath as already directed for alizarin. 
 Purpurin only sublimes, leaving a bulky carbonaceous mass at the bottom of 
 the capsule. During the sublimation pseudopurpurin and the orange matter 
 are partly converted into purpurin. Another method is to heat commercial 
 alizarin, previously well washed with luke-warm alcohol, in a sealed tube along 
 with alcohol up to 200° C. By this process purpurin is obtained in beautiful 
 crystalline needles, whilst a black powder settles at the bottom of the tube. 
 In this instance also pseudopurpurin is converted into purpurin. 
 
 The characters of purpurin are : — colour redder than that of alizarin ; it 
 sublimes at 250 C, but always with partial decomposition, leaving behind a 
 carbonaceous residue. The crystals differ from those of alizarin, and 
 commonly resemble the feather of a quill. When dissolved in boiling alcohol, 
 they are re-deposited, on cooling, in crystalline needles, often 1 centim. in 
 length, of a beautiful red, slightly verging upon orange. If dissolved in alcohol 
 without previous sublimation, they form, on cooling, very small groups of minute 
 acicular crystals. There is, however, no difference in their composition. 
 
 Purpurin is rather more soluble in boiling water and boiling alcohol than 
 alizarin, but is otherwise soluble in the same liquids. Purpurin consists of 
 C14H8O5, or C I4 H 5 2 (OH)3. The carbon and hydrogen are given respectively 
 at 66*67 an d 370 per cent by Wolff and Strecker, but by Debus at 66*38 and 3-87, 
 and by Schiffer and Schiitzenberger 65-93 and 3*29. Potassa, soda, and ammonia 
 dissolve purpurin, yielding characteristic poppy-red solutions, quite distinct 
 from the almost blue solutions yielded by alizarin under the same conditions. 
 The presence of io per cent alizarin mixed with purpurin can be detected by 
 solution in alkaline liquids, since the blue shade becomes distinctly perceptible 
 on dilution with water. Alkaline carbonates and salts, which in solution 
 exhibit a basic reaction, e.g., borax, dissolve purpurin, yielding red solutions. 
 Alum water dissolves purpurin far more readily than alizarin, and the red 
 solution does not, on cooling, deposit a sediment of purpurin, whilst alizarin 
 is, in great measure, thrown down on cooling. The lakes containing both 
 substances together yield purpurin when boiled with solution of carbonate of 
 soda. The combinations of purpurin with bases have great similarity with 
 the corresponding alizarin compounds. The alkaline purpurates are soluble 
 in water ; those of the alkaline earths and metallic oxides insoluble. The 
 former are nearly black, yielding red solutions. Purpurate of soda can 
 be obtained in crystals by a similar process to the alizarate. The alumina 
 lake of purpurin is a full red, without the least trace of blue. The iron-lakes 
 
250 
 
 DYEING AND CALICO PRINTING. 
 
 are either violet or black. When hydrochloric acid is added to a recent solution 
 of purpurin in ammonia, the colour is thrown down unaltered in the shape of 
 orange-yellow flocks. If the solution has been kept even for twenty-four 
 hours, the precipitate resulting from the addition of hydrochloric acid is a 
 deep violet. The same result is obtained by heating the ammoniacal solution 
 to ioo" C. This precipitate gives off ammonia when heated with caustic soda, 
 proving that an amide has been formed, purpuramide or purpureine. It is soluble 
 in boiling alcohol, yielding a deep violet-red solution, and on evaporation 
 forms crystals exhibiting a green reflection like those of murexide. This 
 substance dyes wool and silk an amaranth shade without any mordant. Its 
 formula is Ci 4 H 9 N0 4 , or C I4 H 5 NH 2 (HO) 2 2 . When a mixture of crystallised 
 purpurate of soda, iodide of ethyl, and alcohol is heated in a sealed tube to 
 150 C, there is formed iodide of sodium, and a red crystalline substance 
 sparingly soluble in alcohol. Its formula is C I4 H 5 (C 2 H 5 0) 3 2 . 
 
 Pseudopurpurin is almost insoluble in boiling alcohol, but soluble in hot 
 benzol, from which it separates on cooling in fine acicular crystals of a brick-red 
 colour. Heat, as well as treatment with alcohol at high temperatures in a sealed 
 tube, convert pseudopurpurin into purpurin. Pseudopurpurin dissolves in 
 alkalies with a red colour. With ammonia it forms an amido-derivative, 
 in a similar manner to purpurin. The formula of pseudopurpurin is 
 C I4 H 4 (HO) 4 2 . 
 
 The orange matter is insoluble in boiling benzol ; very soluble in hike- warm 
 alcohol, from which it is deposited, on cooling, either as a thick granular 
 curdy mass, or again as orange scales. This depends on the concentration of 
 the solution. This substance is partially converted by the action of dry heat 
 into purpurin. Its formula, according to Schutzenberger, is C 20 Hi60g. 
 Purpurin, pseudopurpurin, and the orange matter yield with mordants 
 shades resembling those of alizarin, but without a blue reflection. Goods 
 dyed with purpurin and the orange matter resist boiling soap-lye tolerably 
 well, but the shades produced by pseudopurpurin fade away. The power to 
 resist clearing varies, therefore, inversely as the amount of oxygen in the 
 colour. 
 
 The yellow colour, purpuroxanthin, is soluble in alcohol and benzol, 
 sparingly soluble in water, and sublimes when heated almost without decom- 
 position. With aluminous mordants it yields a dull and fugitive yellow, which 
 is destroyed by the per-saltsof tin and by clearing. It is readily obtained by the 
 reduction of purpurin, pseudopurpurin, or the orange matter, by heating to 
 x8o° C. in a sealed tube along with aqueous teriodide of phosphorus. It is 
 more easily prepared by adding some protochloride of tin to a boiling solution 
 of crude purpurin in caustic soda. The solution loses its red colour and 
 becomes orange. The addition of an excess of hydrochloric acid throws 
 down the yellow matter. It is then thrown on a filter, washed, and purified 
 by sublimation and crystallisation from alcohol. 
 
 Turning now to the researches of Schunck on this subject, we may 
 summarise his results as follows : — 
 
 a. By splitting up the rubian under the influence of boiling dilute hydro- 
 chloric or sulphuric acid he obtains- — (1) alizarin ; (2) rubianin, a lemon- 
 yellow matter, crystallisable, and more soluble in water, but less so in alcohol 
 
PURPURIN. 251 
 
 than alizarin, and yielding, on elementary analysis, carbon 57*42, hydrogen 
 5-39, the rest being oxgen. These figures may be formulated — 
 
 C 2 oH 2 oO IO = C 2 oHi206 + 4H20, or C 2 oH 22 IO = C 2 oH I2 06 + H 2 + 4H 2 0. 
 There is little doubt but that rubianin may exist pre-formed in madder ; 
 
 (3) rubiretin, or a resin, a brown-coloured fusible substance ; formula — 
 
 C 20 H i5 Og = C 20 H I2 6 + H 4 . 
 b. By the action of boiling solutions of caustic alkalies rubian yields — 
 (1) alizarin ; (2) the resins a and /3 described above ; (3) a yellow matter 
 obtained in crystals from an alcoholic solution, and capable of subliming. It 
 is soluble in water, and has been named rubiadin. It contains — 
 
 Carbon 71*22 
 
 Hydrogen 4-83 
 
 Oxygen 23-95 
 
 ioo - oo 
 By splitting up rubian with a peculiar ferment (erythrozym) contained in 
 madder it yields — (1) alizarin; (2) resins a and (3; (3) rubiafin, a yellow, 
 crystalline sublimable matter, composed of — 
 
 Carbon 69'30 
 
 Hydrogen 4*56 
 
 Oxygen 26 - i4 
 
 ioo - oo 
 
 (4) rubiagin, a yellow matter, crystallising in small needles, and yielding — 
 
 Carbon 68 - io 
 
 Hydrogen 5-14 
 
 Oxygen 2676 
 
 IOO'OO 
 
 Rubiadin and rubiafin appear to be one and the same substance, representable 
 as C 20 Hi606. Rubiacin, or madder-orange, first discovered by Runge, may be 
 obtained in brilliant flakes and masses, or in the shape of needles of a yellow 
 colour, resembling in shade iodide of lead. This substance is sublimable 
 unchanged, and is sparingly soluble in boiling water, but readily soluble in 
 boiling alcohol. It contains — 
 
 Carbon 67'oi 
 
 Hydrogen 3-28 
 
 Oxygen 2971 
 
 IOO'OO 
 
 Rubiacin dissolves in sulphuric acid, yielding a yellow solution, unaffected by 
 heat. It is decomposed by boiling sulphuric acid. If rubiacin is dissolved in 
 perchloride or pernitrate of iron, a brownish-red solution is formed, which 
 turns yellow on the addition of acids, and deposits rubiacic acid as a flocculent 
 mass. This dissolves in alkalies, giving purple solutions, from which acids 
 re-precipitate the rubiacic acid unchanged. The ammoniacal solution gives a 
 dirty red precipitate with chlorides of barium and calcium. If hydrate of 
 alumina is added to an alcoholic solution of rubiacin it takes an orange 
 colour, whilst the liquid is rendered colourless. This aluminous lake is 
 soluble in caustic potassa, yielding a purple solution, a particular in which 
 
252 
 
 DYEING AND CALICO PRINTING. 
 
 this compound differs from the corresponding alizarin lake. Mordanted cloth 
 scarcely takes any colour if immersed in a boiling rubiacin bath. Rubiacic 
 acid is re-converted into rubiacin by the adlion of sulphuretted hydrogen. In 
 many of its properties rubiacin approaches purpuroxanthin as obtained by 
 the reduction of purpurin. According to Schunck, rubiafin, when acted upon 
 by the per-salts of iron, yields rubiacin. Since rubiafin — CjoHjoOe, it will 
 lose by oxidation 4 atoms of hydrogen, becoming C 20 H i2 0g. 
 
 The following is a summary conspectus of the colours of madder: — 
 
 Original Colours Soluble in Water. 
 
 Glucosides, which by the action of acids, alkalies, and ferments are split 
 up into sugar and colours insoluble in water; 
 
 Rubian (Schunck). Amorphous, bitter, very soluble, precipitablc by porous 
 substances. A mixture of several glucosides. 
 
 Ruberythric Acid (Rochleder). Crystallisable, alizaric glucoside, con- 
 vertible only into alizarin and sugar. 
 
 Colouring Matters, the Existence of which cannot be Doubted. 
 
 Insoluble colouring matters due to the splitting up of the glucosides, and 
 present in the ground madder of commerce. 
 
 1. Alizarin. Readily sublimable without decomposition, orange-red, 
 crystallises in needles; yields in dyeing and printing very fast and beautiful 
 colours, which resist the clearing operations. 
 
 2. Purpurin. Sublimable with partial decomposition ; red, crystallises in 
 needles ; yields in dyeing shades not quite fast, but which stand clearing 
 moderately. 
 
 3. Orange Matter. Crystallises in granular scales, very soluble in alcohol ; 
 yields on sublimation purpurin, but leaves a large deposit of carbonaceous 
 matter. Behaves like purpurin in dyeing. 
 
 4. Pseudopurpurin. Brick-red ; insoluble in alcohol, soluble in boiling 
 benzol, and deposited, on cooling, in crystalline needles ; decomposed by heat, 
 yielding a very small sublimate of purpurin. Gives with mordanted cloth the 
 same shades as purpurin, but none of these stand clearing. 
 
 5. Purpuroxanthin, or xanlliopurpurhi. Yellow, crystalline, sublimable, 
 formed by the reduction of purpurin. 
 
 Colouring Matters of Doubtful Existence, or which Require Further 
 
 Investigation. 
 
 Yellow matters. — Rubianin, rubialin, rubiazin, rubiadin, rubiacin, rubiacic 
 acid. 
 Resinous matters. — Verantin and rubiretin. 
 
 Commercial Products or Derivatives from Madder. 
 The madder of commerce yields, when properly treated, beautiful and 
 exceedingly fast colours with alumina and iron mordants. Care must be 
 taken to submit the dyed fabric afterwards to a series of operations known as 
 clearing (avivage). But madder is in many respects inconvenient as a dye, 
 this defect being chiefly, if not entirely, due to the presence of foreign 
 substances along with the colouring principles. When the previously 
 mordanted or printed fabrics leave the dye-beck, the red, rose, and violet 
 
MADDER. 
 
 253 
 
 shades produced by the various mordants are dull and unsightly, because the 
 mordants fix not merely the alizarin and purpurin, but also the yellow and 
 brown colouring matters. Further, those portions of the fabric intended to 
 remain white, become dirty, because these last-named matters adhere to such 
 parts. In order to utilise all the disposable colouring matter present in the 
 madder, it is requisite to raise the temperature of the bath gradually to the 
 boiling-point. Without this precaution a serious loss would ensue. In addition 
 to these disadvantages of madder, which refer especially to printing calico and 
 silk, not to dyeing wool a uniform colour, it is not possible to utilise all the 
 colouring matters contained in the root. Nearly half the colouring matter is 
 combined with lime-salts and with woody fibre so intimately that it cannot be 
 united with the mordants of the fabric. In consequence the spent 
 dye-material still contains alizarin, which can be utilised, as we shall 
 show below in treating of garanccux. Since the beginning of this century 
 many proposals and attempts have been made to obtain the colouring 
 principles contained in madder in a higher state of purity and concentration. 
 Up to this day no one has succeeded in entirely eliminating the 
 useless constituents present in madder in one operation. The dyers and 
 printers, moreover, exercise great caution in adopting in place of madder 
 preparations about which they can often judge only by somewhat prolonged 
 use. Garancin had to struggle for years against the scepticism of the trade 
 before its use became general. 
 
 In the following pages we propose to classify the commercial preparations 
 of madder according to the kind of treatment to which the madder is sub- 
 jected in their preparation: — 
 
 1. Processes which increase and concentrate the tinctorial power of the 
 madder by the elimination of foreign substances soluble in water, or capable of 
 being rendered soluble by means which do not modify the colouring matter. 
 
 2. Processes whereby the solubility of the colouring matters in certain 
 menstrua is utilised to separate them from materials insoluble in the same. 
 
 3. Processes based upon the volatility of the colouring matters. 
 
 4. Treatment purely mechanical. 
 
 The reader should bear in mind that the tinctorial matters of madder form 
 three groups — the glucosides soluble in water; the colouring matters free but 
 mechanically mixed with other vegetable matter ; colours intimately com- 
 bined with woody fibre. The heart of the root, a very hard tough woody 
 mass, contains a large amount of excellent colour. The heart of the Zealand 
 root may be readily obtained, and after having been separately ground, yields 
 pure alizarin on being sublimed with care in small portions. 
 
 First Group. — 
 
 Fleur de garance, or flowers of madder, of Julian and Roquer, of Avignon. 
 This preparation should not be confounded with the older preparation of 
 Robiquet, Colin, and Lagier of the same town, which is now known as 
 garancin. As far back as 1823, Kuhlmann came to the conclusion that 
 washing madder in cold water would be an easy method of removing gum, 
 sugar, and certain extractive and yellow colours, such as xanthin. When 
 madder, thoroughly moistened with water, is left to stand previous to being 
 washed, a fermentation of a peculiar character ensues, which splits up the 
 glucosides, and increases the tinctorial power to some extent. 
 
254 
 
 DYEING AND CALICO PRINTING. 
 
 In 1846 and 1847 Roux patented the application of fermentation to madder to 
 obtain thereby a peculiar preparation. This process was found very capricious, 
 since the temperature, the duration of the steeping, the quantity, and also the 
 quality of the water so much affect the results that a slight change in any of 
 these particulars is enough to render the madder useless. 
 
 Julian and Roquer describe their own process thus : — We take madder roots 
 and reduce these to powder; the madder thus obtained is placed in tanks, and, 
 after the addition of water, is thoroughly and vigorously stirred up with that 
 water, which we take cold or hot, and which we treat according to its degree of 
 purity with any acid to eliminate its contained lime-salts. We then run the entire 
 contents of the tanks into the filtering boxes, consisting of stout wooden 
 frames, lined with flannel ; the bulk of the liquid is suffered to run off, and, 
 according to the product we desire to obtain, we leave the madder in these 
 boxes for a length of time, varying one to five or six days, according as it 
 suits cur purpose to produce alcoholic fermentation or not. The madder is 
 taken from these boxes and put into stout linen bags, and strongly pressed by 
 means of hydraulic presses of great power ; the pressed cakes are dried in 
 stoves (heated by steam, and arranged similar to those of the sugar refineries), 
 ground up to powder, and packed into casks. The liquids are either collected 
 for fermentation or run off into the sewers; if fermented by the addition some- 
 times of beer yeast, but chiefly by means of sufficient fermentation- 
 inducing nitrogenous matter present in the liquors naturally, we submit the 
 latter to distillation and obtain alcohol. The first samples of their product 
 were sent in January, 1851, on trial to Mulhouse, and in February, 1852, 
 Messrs. Julian and Roquer had sent off from their works at Avignon 300,000 
 kilos, of fleur de garance. By the process described the madder loses half of 
 its weight of useless materials. 
 
 M. Pernod, of Avignon, has kindly given the writer the following information 
 on the more recent mode of preparing bloom of madder: — The madder is 
 mixed with from eight to ten times its weight of river water (the less saline 
 matter present the better), to which just so much sulphuric or hydrochloric 
 acid is added as will saturate the carbonate of lime always present in the 
 pulverised madder. When sulphuric acid is employed, from 1 to 2 kilos, of 
 the concentrated acid are applied for every 100 kilos, of madder; the addition 
 of the acid is chiefly made when it is intended to prepare a material particularly 
 suitable for the dyeing of red and brown colours, but when the preparation of 
 a material especially suited for violet dyeing is desired, no acid at all is used : 
 this operation is done in a wooden tank, lined inside with stout flannel, which 
 rests on a false perforated bottom, between which and the real bottom a small 
 space is left provided with one or more taps, so placed as to ensure the 
 running off the liquid when desired, while the pasty mass remains on the filter 
 supported by the false bottom. The madder is left macerating in the liquid 
 for about twelve or fifteen hours, when it is tapped off; and since this has 
 taken up the largest portion of the sugar present in the madder, it is run into 
 tubs of suitable size and construction, and left to ferment, to be converted 
 into alcohol by distillation. The pasty material which remains inside the tank 
 is immediately taken out and placed in stout linen bags, in quantities of from 
 3 to 4 kilos., and submitted to very strong pressure by means of the hydraulic 
 press, in order to remove the largest portion of the liquid ; after which the 
 
MADDER. 
 
 255 
 
 material is removed from the bags. It is transported to the drying-stove, and 
 after having become quite dry it is reduced to powder by mill-stones similar to 
 those used for the grinding of madder. This millwork is very different from 
 that used for grinding grain, and more resembles that in use for grinding 
 coprolites. The ground-up material is packed in casks, commonly lined 
 with stout paper inside, while the seams between the staves are covered with 
 pitch. 
 
 Bloom of madder is also prepared by mixing the madder with from eight to 
 ten times its weight of river water, and leaving this mixture for from two to 
 four days at rest, at a temperature of from 18 to 25 . When the alcoholic fer- 
 mentation which sets in is complete the liquid is run off, and the operation is 
 finished as just mentioned. When the alcoholic fermentation takes place in 
 the presence of a large quantity of water, the colouring principles of the 
 madder do not suffer any change, and are not decreased in their tinctorial 
 value ; but when either the pasty mass — above referred to as left in the filter 
 tank — or the pressed cake is suffered to undergo fermentation, the colouring 
 principles are sometimes altered and somewhat deteriorated, and on that 
 account, and in consequence of the irregularity of the fermenting process 
 under these conditions, it is no longer used in the Avignon district. 100 kilos, 
 of madder 'yield from 55 to 60 kilos, of bloom of madder, according to the 
 nature of the raw material. Generally speaking, the better qualities of madder 
 yield a less weight than the lower qualities, but the tinctorial value is very 
 superior. The quantity of madder annually converted into bloom of madder 
 in the Avignon district amounts to 4,000,000 kilos. 
 
 The manufacture of alcohol from madder is a profitable business : 100 kilos, 
 of madder yield from 7 to 10 litres of alcohol, at 87 per cent ; the superior 
 kinds of madder yield a larger quantity than the lower. This alcohol, in the 
 raw state, is unfit for drinking. Its taste is very disagreeable, and its smell 
 much like that of wood-spirit. It is employed for the preparation of varnish 
 and ether. M. Schiitzenberger states, probably upon the authority of some of 
 the distillers resident in the Avignon district (it should be mentioned that some 
 of the manufacturers of fleur de garance are distillers at the same time, but 
 many sell the fermented or fermentable liquid, or raw spirit, to distillers), that 
 the alcohol from madder can be rendered quite sweet by contact with porous 
 substances — especially pumice-stone and wood-charcoal — and re-distillation, 
 and then become as good as rectified beet-root alcohol. There is established 
 at Sorgue, near Avignon, an extensive distillery, wherein the largest portion 
 of the alcohol obtained in that district is rectified and purified to such an extent 
 as to compete successfully with the alcohol obtained from wine. According 
 to the opinion of some chemists * the peculiar odour and taste of the alcohol 
 
 * The researches of Gunning, of Amsterdam, have proved that the odour of the alcohol 
 obtained from the washing-liquors of garancin und/leur de garance is due (in the case, at least, 
 of Zealand madder) to acetic ether and aldehyde. The raw madder-spirit is an excellent 
 source for aldehyde-ammonia. The preparation is as follows :— From 20 to 30 litres of the 
 impure spirit are placed in a still provided with a long copper worm, and heated to 6o° or 70 
 C, while at the same time a rapid current of air or carbonic acid is passed over the liquid. 
 The distillation is continued until the distillate ceases to give a darkish colouration with 
 caustic potash-lye. To the distillate is added twice its bulk of water, powdered hydrate of 
 baryta being stirred in till a decided alkaline reaction is perceived, in order to decompose the 
 acetic ether. The excess of baryta is removed with carbonic acid. Aldehyde is afterwards 
 
82J£3aE3^3 S*m! -wWK' 
 
 
 &M£*flSsSv*rvr& 
 
 mni 
 
 256 
 
 DYEING AND CALICO PRINTING. 
 
 obtained from madder is due to amylic and other homologous alcohols, 
 and partly to the existence of a peculiar camphor-like substance present 
 in madder, and known as campbor of madder. This substance, according 
 to the researches of M. Jean Jean, is isomeric with the Borneo camphor 
 (C IO HisO). The camphor from madder can be obtained in small hex- 
 agonal prismatic crystals ; it is hardly soluble in water, readily so in 
 acetic acid, alcohol, and ether, and turns the plane of polarisation to the 
 left. The great advantage of flcur de garmice, or rather its superiority to 
 madder, especially for printing, is owing to the purity and great beauty of the 
 violet tints produced by this material, with equal fastness but superior bril- 
 liance. The simple reason is, that by the operation to which madder is sub- 
 jected, to produce bloom of madder, all the soluble, mucilaginous, saccharine, 
 and brownish-coloured matters aie removed from that substance ; and since 
 these substances interfere with iron mordants, and thereby deteriorate the 
 violets, it is clear that flowers or bloom of madder yield a superior violet. 
 
 With alumina and iron mordants bloom of madder produces deeper shades 
 than madder. This seems to be due to the solvent action exercised upon the 
 mordants by the substances soluble in water present in madder ; and the 
 degree of this action may be judged from the fact that when bloom of madder 
 is used the same intensity of colour is produced as with madder, with mor- 
 dants of from fifteen to twenty times less strength than madder would require. 
 The rose-red and red shades produced by fleur de garance are quite as beau- 
 tiful as those which madder gives, and have, as compared with madder, the 
 advantage of greater fastness. The portions of the fabric intended to remain 
 white are less soiled when bloom of madder is used than is the case when 
 madder is employed. There is an advantage gained, also, in respect of 
 clearing and soaping. The other advantages of bloom of madder are — 
 greater regularity of dyeing; less difficulty in the management of the dye- 
 bath; the possibility of adding a fresh portion of bloom to the bath when it 
 appears exhausted, which cannot be done when crude madder is used ; and 
 the perfect exhaustion of all colouring matter from the bath. It should be 
 understood, however, that what is here said relates exclusively to calico- 
 printing, — that is to say, to the passing of calicoes, muslins, and such-like 
 fabrics, upon which designs have been printed by rollers supplied with the 
 requisite mordants, through the dye-baths. Bloom of madder is not used in 
 dyeing woollen fabrics to which a uniform shade is to be given, neither for 
 Turkey-red. Bloom of madder is preferable, since for equal weights it con- 
 tains twice as much colouring matter as madder, and it has the decided 
 advantage that it is less sensitive to damp warehouses, and does not, like 
 madder, become spoiled by age. 
 
 The length of time madder can be kept and preserve its full vigour differs 
 for different kinds of madder. Counting from the moment the ground material 
 is packed in casks, Avignon madder and the produce of Southern Europe 
 
 separated from the liquid by careful distillation in the water-bath, and purified by combination 
 with ammonia. If the impure madder-spirit is agitated with sodium amalgam, perfectly pure 
 alcohol is obtained, since the aldehyde is thus hydrogenised to alcohol, the acetic ether being 
 also decomposed with formation of alcohol and acetate of soda. The opinion has been enter- 
 tained that there is a relation between the amount of sugar present in madder and the amount 
 of the tinctoiial principles. 
 
MADDER. 
 
 257 
 
 and the Levant are in full perfection before the end of a twelvemonth. 
 Alsace, Baden, and Wurtemburg madders are perfect in about sixteen to 
 nineteen months. Zealand madder reaches its climax, for all shades, at 
 from twenty to twenty-six months. This is the unanimous testimony of 
 Mulhouse, Rouen, Elberfeld, and other places where this material is con- 
 sumed, and is supported by Gasparin, Girardin, Previnaire, and other 
 scientific men, that no known kind of madder produces then such fast, such 
 brilliant, and such intense colours as that of Zealand. There is the drawback 
 of clearings, and, as regards the white portions of tissues, almost an impos- 
 sibility of brightening them without grass-bleaching. The other kinds of 
 madder are entirely spoiled, even within a few weeks after having reached 
 maturity. Zealand madder, if properly kept, is — even at thirty-six months of 
 age — quite fit to dye excellent deep browns and exceedingly beautiful blacks. 
 Gasparin accounts for this by the mode of cultivation to a great extent, and 
 by the peculiarities of the soil. The proper packing of the material and the 
 care of warehousing it in suitably constructed and ventilated — yet dark* — 
 buildings have been proved to have much to do with the good qualities of 
 Zealand madder, by the experience of the brokers and warehousemen who 
 have charge of this article at Rotterdam. There higher rents are readily paid 
 for warehouses suitably constructed to keep madder. An equable temperature 
 is also a great point. 
 
 We now return to fleur de garance : from its mode of preparation we may 
 already infer that, as is the case with madder, the colouring matter intimately 
 combined with and pre-existing in the woody fibre is lost. According to M. 
 H. Schlumberger, 100 parts of fleur s de garance are equal to 200 of madder, 
 but the loss of colouring matter just alluded to is the same for both, and 
 amounts to about 45 per cent. Hence for bloom of madder, as well as for raw 
 madder, there exists the necessity of treating the residues for garanceux, 
 about which we shall treat presently. 
 
 We have now to treat of Garancin (once known as Lagier's bloom of 
 madder). The principle of the manufacture of garancin is based upon the 
 action which sulphuric acid, in a more or less concentrated state, has upon 
 madder, whether previously washed or unwashed with water. The action of 
 the acid destroys a portion of the woody fibre, and while it does not affect the 
 genuine colouring principles it removes the useless vegetable matter, dissolves 
 the calcareous and other combinations of the colouring substances, and sets 
 so much of the latter entirely free that a real gain is obtained, so great as to 
 cover far more than the expense of the acid and the manipulations required. 
 
 As far back as the year 1828 Robiquet and Colin wrote a paper, presented to 
 the Societe Industrielle de Mulhouse, "On the Concentration of Madder by 
 Means of Sulphuric Acid." These chemists proposed to treat Avignon madder 
 with a quantity of concentrated sulphuric acid equal to its own weight, or 
 even somewhat more. They thus obtain what they call charbon sulfurique, rich 
 in colouring matter, and fit for dyeing purposes after washing out the acid. 
 This substance, however, has never been manufactured on the large scale, nor 
 
 * While direft sunlight is carefully avoided, even daylight is hardly admitted in these places, 
 and a too great damp, as well as too great heat, are considered injurious, but extreme cold is 
 equally avoided. Care is taken now and then to move the casks, i.e., roll them about 
 thoroughly. 
 
wmBBBmmmmi 
 
 258 
 
 DYEING AND CALICO PRINTING. 
 
 has it ever served the use of dyeing. All that has ever been done with the 
 comparatively small quantity made has been its extraction, either with alcohol 
 or a boiling solution of alum, to prepare what has been called the colorin of 
 Messrs. Lagier and Thomas. M. Henri Schliimberger has, however, tried 
 dyeing with this charbon sulfurique, and found that it gave the red, violet, and 
 black tints perfectly well, while the white portions of the tissue were almost 
 unsoiled. No action ensued until the boiling-point of the liquid in the dye- 
 beck was nearly reached. 
 
 In 1828, Lagier, Robiquet, and Colin took out a patent, from the text of 
 which it is quite clear that they intended to produce from madder a more 
 easily manageable suustance by means of sulphuric acid. They proposed 
 (and actually carried out) a preliminary washing of the madder with water, 
 in order to remove from it all soluble matter. In consequence, the quantity 
 of sulphuric acid was decreased, since, by the previous washing out of a 
 portion of the sugar, that substance no longer neutralised the effect; of the 
 acid, although the addition of the concentrated acid to a thoroughly moist 
 mass would, of course, cause its dilution to some extent. More water was 
 added to the acid previous to its addition to the washed and moist madder, 
 which immediately after was heated, by means of steam, to ioo°. This is, 
 briefly related, the original method of making garancin. This substance has 
 only very gradually come into use. 
 
 At present garancin is made as follows : — Madder is mixed with from 
 eight to ten times its weight of water, acidulated with sulphuric or hydro- 
 chloric acid ; from 1 to 2 kilos, of acid for every 100 kilos, of powdered madder 
 being a sufficient quantity. As regards the acids, it is essential that the sul- 
 phuric acid should be, as far as possible, free from nitric acid or nitrous 
 compounds, and should not contain metallic substances in solution. The 
 hydrochloric acid ought not to contain any free chlorine, and should be also 
 free from metallic compounds. These particulars are too often overlooked, 
 yet experience, especially in Holland, has proved that the goodness of the 
 acids influences the goodness of the garancin produced. This washing 
 process is executed in large wooden tanks, fitted with a stout flannel lining, 
 resting upon a false or perforated bottom, as already described for the prepa- 
 ration of fleur de garance. 
 
 In the case of garancin the madder is left steeping in the acidulated water 
 for about seven to twelve hours, after which the liquid is run off. This fluid 
 also serves for the manufacture of alcohol. The mass in the tank is trans- 
 ferred to another wooden tank, and sufficient water is added to make a thin 
 paste of the whole, to which there is then added — for every 100 kilos, of madder 
 originally taken — 30 kilos, of strong sulphuric acid or 40 kilos, of strong 
 hydrochloric acid. After this mixture has been well stirred up the cover of 
 the tank is closed, and, by means of a lead pipe, steam is introduced into the 
 magma, which is kept boiling for three or four hours. When ebullition has 
 been kept up for that time, the contents of the tank — while yet hot — are 
 brought over into a very large tank, lined with flannel and provided with a 
 perforated false bottom, This tank is partly filled with cold water, the purer 
 the better, the water having a decided influence upon the goodness of the 
 resulting garancin. After all the material is transferred from the boiling tank 
 into the filtering basin, the water contained is run off and fresh water added, 
 
MADDER. 
 
 259 
 
 and the washing repeated three to five times. The last washings assume a 
 colour not unlike red Hermitage wine.* When the liquid has run off as far as 
 possible the garancin is farther dried, first by being pressed — in powerful 
 hydraulic presses — into cakes, which, after having been stove-dried, are broken 
 up and reduced to powder by a mill. 
 
 The washings from garancin — especially the first, which contains most of 
 the acid — are applied in various ways, either for washing illuminating gas, and 
 removing ammonia therefrom, or for dissolving phosphatic minerals for the 
 manufacture of artificial manures and the like ; the subsequent washings 
 contain, according to recent reports,! a peculiar pigment, and also oxalic acid. 
 
 One hundred kilos, of madder produce from 34 to 37 kilos, of garancin, 
 according to the quality of the madder employed. The superior qualities 
 yield a smaller quantity of garancin than the inferior. When madder which 
 has not been previously washed is acted upon by acid, as just described, the 
 result is a very dark — almost carbonised — material. This colouration is due 
 to the decomposition of the chlorogenin, which is converted into chlorrubin. 
 
 There are several points connected with the manufacture of garancin which 
 are scarcely or not at all explained by Science, and, moreover, its preparation 
 from Zealand madders especially requires far more careful study and attention 
 than is the case with Avignon or other madders grown in Southern Europe. 
 What is the real and essential action of the acids in producing garancin is not 
 known. It has been thought that they acted by breaking up the woody fibre, 
 tearing it asunder, and letting the water get access to the colouring particles 
 previously enclosed, and so transferring them to the dye-bath ; but the 
 weakness of the acids which can be employed, consistent with successful 
 issue, is fatal to this explanation. The supposition that the colouring matter 
 is in a state of combination with some earthy base, as lime and magnesia, and 
 that it cannot dye while so combined, and that the acids liberate the colouring 
 matter by combining with the bases, is an explanation not supported by any 
 real facts or experiments. It appears probable that some chemical affinities 
 of a more refined and subtle nature are brought into play. It is likely that 
 the acid employed forms a combination with the colouring matter, which is 
 itself easily decomposed even by water. It is not in accordance with analogy to 
 suppose any formation or creation of colouring matter, but simply that a 
 portion of the colouring matter is present in some form or other upon which 
 water cannot act, whilst acids in some unknown manner make it susceptible 
 to the influence of water. There are some ascertained facts bearing upon the 
 action of acids upon the colouring matter of madder, which, though they have 
 no direct practical significance, are full of suggestions. It is very well known 
 that garancin is not the same as a dyeing material as madder. Its colours 
 are not so fast, either as against soaping, clearing, or exposure to air ; the acid 
 having evidently, if not injured, at least somewhat altered, the colouring 
 matter in setting it free. It is no longer what it was in the untouched root. 
 Chemistry has hitherto failed to explain this, which, as a fact, stands in oppo- 
 sition or exception to other known cases of the action of acids upon the 
 colouring matter of this root. For example, a piece of Turkey red cloth or 
 dark purple dyed with madder can be treated with strong sulphuric acid, which 
 
 * Genuine Hermitage rouge has a delicate yellowish rose-red shade. 
 t See " Chemical News," vol. xxi., p. 58, February 4, 1S70. 
 
 S 2 
 
W*rifrwp»««.*3asl«5 
 
 
 £gz%P 
 
 W3$&^^Bs 
 
 260 DYEING AND CALICO PRINTING. 
 
 will take up the mordant, and leave the colouring matter loosely attached to 
 the cloth. The acid can be removed by washing, and then the colour extracted 
 by spirits of wine. This colouring matter may have been subjected to the 
 contact of acid quite as strong as that used in making garancin (and even far 
 stronger), and for as great a length of time, but it is not affected like the 
 colouring matters in garancin. It can still dye up fast reds, pinks, and 
 purples, upon mordanted cloth; yielding colours which are not injured, but 
 improved, by soaping and clearing. The question arises, Why should acids 
 act so differently in one case and in the other ? It can be easily understood 
 how great an advantage it would be if garancin gave as fast colours as madder. 
 This result may perhaps be accomplished when we have a more accurate 
 knowledge of the action of acids upon madder. 
 
 In the beginning of 1870 a brief private communication was received 
 by us from the chemist in charge of the four largest garancin works in 
 Holland. The manufacture of garancin from Zealand madder, made by the 
 old-fashioned plan, is attended with some practical difficulties, to remove 
 which the aid of science has been called in. Researches have been made — 
 not only by the chemist just mentioned, but also by Prof. Mulder, of 
 Utrecht, and others — which show that the garancin so prepared is as good 
 for all practical purposes as the best madder, and the colours are equally fast, 
 while the dyeing operations are easier and take less time in clearing; the 
 process, however, is kept a trade secret. We are informed that this garancin 
 also dyes Turkey red rapidly. 
 
 The Avignon garancin usually met with in commerce is a finely pulverised 
 powder, of a more or less deep brown colour. The ligneous matter is not at 
 all carbonised, as can be proved by exhausting the substance successively with 
 soda and acid, when a residue is obtained free from colouring matters, hardly 
 any deeper in colour than fleur de garance. 100 grms. of garancin yielded 
 from 16 to 17 grms. of pectic acid, the greater part of which is in a free state, 
 while a small portion is combined with lime. At the same time 48 grms. of 
 ligneous matter (woody fibre) is obtained. Since 100 grms. of madder 
 (Avignon) containing 20 of ligneous matter yield about 40 grms. of garancin, 
 it is clear that the woody fibre is very little acted upon by the treatment with 
 sulphuric acid. 
 
 The tinctorial value of garancin of good quality is from 4 to 4*5 — even 
 sometimes 5 — times greater than that of the madder it is obtained from ; 
 100 parts of madder, by weight, yield from 36 to 40 parts of garancin. 
 
 While garancin has its decided advantage, especially as regards the great 
 saving of time, expense, and labour in the production of coloured designs for 
 printing, it cannot be used as a substitute for madder. Garancin colours are 
 less fast and solid than those from madder with the same mordants, and some 
 of the shades are always decidedly inferior to madder shades of the same kind. 
 It has been proposed to remedy this defect by the addition of a small quantity 
 of chalk to the garancin bath, but this remedy is attended with a real loss of 
 what was gained by the previous treatment of the dye-stuff with acid. The 
 generally prevailing opinion on this practical inconvenience is, that it is due to 
 the presence of a small quantity of ligno-sulphuric acid* which is intimately 
 
 * There have been numerous proposals made, and a large number of Patents have been taken 
 out, to remove from garancin all the sulphuric acid, but the application of alkalies — even in the 
 
GARANCEUX. 
 
 261 
 
 combined with the material, and not removable by washing with water alone. 
 The experiments made by Schwartz with oily extracts from garancin yielded 
 shades as fast and beautiful as those from flowers of madder, while the addition 
 of the ligneous matter from garancin was alone sufficient to impair these 
 characters. 
 
 Some manufacturers add to the garancin, after having been stove-dried and 
 while being ground up, a small quantity of bicarbonate of soda or precipitated 
 chalk, well washed and dried, in order to absorb the acid. It has also been 
 proposed to improve garancin by exposure to the vapours of ammonia, and to 
 dry the material afterwards by steam. 
 
 Garanceux. 
 The manufacture of garanceux from spent madder is essentially the same as 
 that of garancin, and the same general explanations apply equally to either. 
 The method of making garanceux is simple and well understood, and requires 
 nothing but care and attention to yield regular results. The spent madder 
 from the dye-beck and wince pits is collected in a sufficiently large pit and 
 allowed to settle, usually with the addition of weak sulphuric acid, which both 
 stops any inclination to fermentation and throws down a fine powder which 
 otherwise floats in the liquor. The wet mass should be well pressed, until it 
 does not contain more than two-thirds of its weight of water. Instead of a 
 press, the centrifugal hydro-extradtor— as used in sugar-refineries — is often 
 used, with the advantage that it is not needful to break the matter up after- 
 wards. The quantity to be used of the acid may vary, but a dozen pounds of 
 brown acid (chamber acid) is a good proportion to the hundredweight of spent 
 madder. The acid should be mixed, before being added to the madder, with 
 about 3 gallons of water. It is essential that the acid touch all the particles 
 of madder, and therefore the material should be thoroughly worked through ; 
 after which the mass may be left for da5's, or even weeks, before it is steamed. 
 The operation of steaming must be watched, to see that all the madder gets a 
 fair proportion of steam. If the spent madder be too moist it sets in the 
 steaming cisterns, and forms chinks, through which the steam blows without 
 permeating the whole mass. It should be so moist as to yield water upon 
 pressure between the fingers, but not wet enough to stick together when 
 pressed in the hand. The thorough washing of the garanceux is of course 
 important, but it has the advantage of washing much faster and more easily 
 than garancin, on account of its loose structure. The washing is known to be 
 accomplished by the liquor no longer tasting acid, and by the appearance of a 
 fine slimy powder, which never shows till the washing is almost completed. 
 It is not advisable to use any alkali to neutralise the remainder of the acid, 
 but it is sometimes done, and then crystals of soda or milk of lime may be 
 added in proper quantity. It keeps better if left a little acid, and can be 
 neutralised in the dye-beck with safety. When the washing is complete it 
 should be pressed again. 
 
 Well pressed garanceux contains between a third and a fourth of its weight 
 >f dry matter, the remainder being water. Its tindlorial value, in proportion 
 to garancin of the first quality, will vary according to the nature of the madder, 
 
 state of bicarbonates and of ammonia gas — has (unless very carefully applied and skilfully 
 managed) the effect of injuring the garancin. Many years ago Drs. van Vlaandcrey and Baunv 
 hauer proved garancin to contain ligno-sulphuric acid. 
 
"VHHH 
 
 262 
 
 DYEING AND CALICO PRINTING. 
 
 and to the proportion in which it has been spent in the first dyeing. Garanceux 
 from mixed Turkey (Levant) and French madder is equal, as it comes from 
 the press, to from one-sixth to one-ninth of its weight of really good 
 garancin. When dried it is equal to about one-third. It is of the utmost 
 importance to see that the garanceux is properly neutralised either in the 
 dye-beck or before it goes in. An error on either side, that is to say, an in- 
 sufficient or an excessive quantity of alkali, is equally injurious. The most 
 useful matter for neutralising garanceux in the becks is bicarbonate of soda, 
 which is very regular and mild in its action. The proportion to be used 
 depends, of course, upon the degree of acidity ; the highest amount required 
 is about 1 lb. of soda to 70 lbs. of garanceux. If the acidity passes this 
 limit good results will not be obtained, and the garanceux should be washed 
 over again. The lowest amount of soda required will be about 1 lb. to 100 or 
 150 of garanceux taken in the wet state." The injurious effects of too much 
 soda are perhaps even more marked than a slight deficiency. The colours 
 are dull and cloudy without brilliancy or solidity. A deficient quantity of soda 
 is shown by a redness of the chocolate colours, poorness in the blacks, and 
 general bareness of the whole of the colours. The colours which garancin and 
 garanceux yield with properly mordanted cloth are the same as those from 
 madder; the whites are purer, on account of the absence of the soluble matters 
 which stain them in madder dyeing. The colours will not stand a severe 
 soaping, and cannot be brought to the same degree of brightness as those 
 produced from madder. These products are not much employed alone, but 
 generally in combination with some of the cheaper dye woods. 
 
 Commercial alizarin or pincoffin has been sold by M. Pincoffs, of 
 Manchester, since 1854. This material is remarkable for the beautiful 
 lilacs or violets it yields without soaping. It also admits of producing 
 combinations of lilacs with catechu, lilac and chocolate, and lilac and 
 orange, which results cannot be obtained satisfactorily with madder or 
 garancin. This material, further, economises the mordants, and produces 
 lilac shades, which may be graduated ad libitum as to cost. 
 
 Pincoffin is prepared by submitting garancin of good quality, and as neutral 
 as possible, to the action of dry or superheated steam. It may also be obtained 
 by heating garancin or fleur de garance to 200 C. on an oil or sand-bath. It 
 is very probable that the chief result of this operation is the destruction of 
 the fawn-coloured resinous matter which is associated with alizarin. Hence 
 the colour cannot foul the purples or lilacs by its action upon the iron mordants. 
 When fleur de garance, dried at igo°, is acted upon by fluoride of boron a 
 carbonaceous matter is obtained, which, after washing with water, yields, on 
 being heated with alcohol, a colouring matter^dyeing lilacs and purples as well 
 and as beautiful as the commercial alizarin. The tinctorial value of the com- 
 mercial alizarin is rather lower than that of garancin. Some authorities state 
 that about from one-sixth to one-fourth more of this material is required for 
 the saturation of an equal weight of mordant for lilac. 
 
 Mr. Higgin has devised another method of preparing commercial alizarin. 
 He boils garancin with some carbonate of soda or a little ammonia. The 
 liquid, which is alkaline at starting, becomes acid after boiling for twenty-four 
 hours, when the garancin is converted into alizarin. 
 
 M. E. Schwartz has proposed to substitute for garancin a preparation 
 obtained by mixing gradually in the cold fleur de garance with from four to 
 
MADDER. 
 
 263 
 
 five times its weight of sulphuric acid of sp. gr. 1714, or 143 T\v. By this 
 operation a portion of the ligneous and pectic matters become so disintegrated 
 as to be soluble in water. The magma of fleur de garance and acid is there- 
 fore poured into a very large bulk of water, when a sediment is thrown down, 
 which, after having been thoroughly washed, dried, and pulverised, becomes 
 a fine brick-red powder, known in commerce as "carmine-madder." This 
 material has a tinctorial value exceeding that of madder by seven or eight 
 times. Owing to practical difficulties, and the expense of production on the 
 large scale, this substance has never been manufactured to any extent. It 
 yielded, when tried on the small scale, exceedingly good results in dyeing. 
 
 Second Group. — 
 
 Mechanical Process of Purifying Madder. — M. Pernod has tried to 
 wash the previously coarsely ground madder root upon a metallic wire gauze 
 sieve under a current of water, whereby the colouring matter is carried 
 off, while there remains on the sieve a greyish-looking, woody, fibrous material 
 not containing any more colouring substances. The pigment washed out is 
 allowed time to settle under water. The water is run off, and the substance 
 is placed on filters and dried. The brown powder thus obta-ned has a 
 tinctorial value seven or eight times greater than that of flowers of madder, 
 yet it contains, as might be expected, a large quantity of foreign matter. 
 
 The processes based upon the solution and consequent extraction of the 
 colouring matter of madder are very many; indeed we may say that nearly 
 all the solvents capable of taking up the colouring matters from madder have 
 been tried to produce what may be in a general way called extracts of madder. 
 Many of these materials have a high tinctorial value, exceeding from twenty 
 to seventy times that of the same weight of madder. These substances are 
 sometimes named after the vehicle employed for extraction. Thus we have 
 the alcoholic, methylic, glyceric, and acetic extracts, to which names are 
 usually added those of the inventors. These substances contain in general 
 the colouring matters more or less contaminated with resinous and extractive 
 matter. When these madder derivatives are treated repeatedly with a boiling 
 solution of alum the resinous matter is left, while the colouring principles are 
 dissolved. The same result is obtained when these extracts are exhausted 
 with water heated under pressure to 250 . As far as these substance have 
 been actually employed, they have answered well in dyeing printed fabrics, 
 especially if chalk is added. The bath requires almost a boiling heat, and, 
 in order to exhaust the colouring matter, it is best to rub the dry extract 
 up with alcohol, and to use far less water in the beck than with raw madder. 
 When madder and flowers of madder are acted upon by any neutral solvent, 
 e.g., alcohol, wood-spirit, sulphide of carbon, glycerin, or by mild alkaline 
 solvents, as carbonate of soda, phosphate, pyrophosphate of soda, weak 
 caustic soda, or any alkaline borate, silicate, or oleate, that portion only of 
 colouring matter is extracted which exists in a free state, while the portion 
 intimately combined with the ligneous matter is left untouched. A complete 
 exhaustion of the colouring matter can only be effected by the aid of mineral 
 acids, which disintegrate the woody fibre and decompose the calcareous com- 
 bination of the colouring matters. Hence it is clear that the preparation of 
 the above extracts can be only suitably performed with either fleur de garance 
 or garancin, or with charbon sulfurique. 
 
BHBWmmmmbm mmumu 
 
 264 
 
 DYEING AND CALICO PRINTING. 
 
 We will now rapidly review the methods which have been employed for 
 obtaining extracts of madder : — 
 
 1. Messrs. Robiquet and Colin exhaust their charbon sulfurique either by 
 means of a boiling solution of alum, and precipitate the colouring matter with 
 sulphuric acid; or they employ alcohol first, cold, to wash out a resinous 
 greasy matter, and a deep red-brown liquid not applied for any useful purpose, 
 though the alcohol is recovered. The charbon sulfurique is next exhausted 
 with boiling alcohol in a suitable apparatus. In this manner a very concen- 
 trated tincture is obtained, from which the colouring principles are abstracted 
 by the addition of water. The precipitate is separated by filtration, and after 
 having been pressed to remove moisture, is sold under the name of " Colorin," 
 The tinctorial value of this substance is equal to seventy times its weight 
 of madder, a result especially due to the treatment with cold alcohol, whereby 
 the greater part of the resinous matter has been got rid. Garancin as now 
 made can be treated in the same way, yielding the same results. 
 
 2. M. Kuhlmann treats madder with boiling alcohol, evaporates to the con- 
 sistence of an extract, which he washes with water to remove the substances 
 soluble therein. This process is faulty, as it is impossible thus to extract all 
 the useful matter from the ground root. 
 
 3. MM. Persoz and Gaultier de Claubry exhaust madder — first, with a 
 boiling solution of carbonate of soda, and next, with an alum solution heated 
 up to ioo*. The sodic solution yields, on saturation with an acid (chlorhydric), 
 a gelatinous precipitate of pectic acid mixed with colouring matter. This 
 precipitate may be treated with alcohol, which leaves pectic acid and takes up 
 the pigments. 
 
 4. M. Dandrillon steeps madder in hydrochloric acid, and treats next with 
 boiling alcohol. The filtered liquid is saturated with chalk, concentrated, 
 and precipitated by means of water. 
 
 5. M. Colomb steeps madder in dilute nitric acid, and washes the acid out 
 after some hours. The madder is next submitted to the action of caustic soda 
 lye (sp. gr. 1*094= 18 Tw.). The violet-coloured alkaline solution is precipitated 
 with dilute nitric acid, and the ensuing bulky precipitate is well washed and 
 treated with boiling alum, whereby the colouring matter is taken up and re- 
 precipitated by means of any acid. The solution may also be precipitated by 
 means of carbonate of soda, yielding a madder lake. 
 
 6. According to M. E. Schwartz, a large portion of the colouring matter of 
 madder may be readily extracted from either garancin or fleur de garance by 
 hot poppy or any other boiling oil. On cooling these oils deposit an extract, 
 which yields brilliant, fast, and resisting colours. 
 
 7. MM. Gerber and Dollfus exhaust fleur de garance with boiling wood- 
 spirit. The concentrated liquors are precipitated with water, yielding 6| per 
 cent of a yellowish-brown extract. The residue of the raw material is acted 
 upon by a fresh quantity of wood-spirit, acidified with 1 ^ v th of its bulk of 
 sulphuric acid. In this way another portion of extract is obtained almost 
 equal in quantity to the first. This last product has been employed and sold 
 under the name of azala. 
 
 8. MM. Verdeil and Michel operate as follows: — The unground dried root is 
 first steeped in water acidulated with sulphuric acid ; next broken up by being 
 squeezed and torn to shreds by means of fluted rollers. The material thus 
 
MADDER. 
 
 265 
 
 obtained is submitted to hydraulic pressure, and steeped for forty-eight hours 
 in a weak solution of carbonate of soda, sp. gr. 1-014 = 3° T\v. The material 
 is again squeezed and thus freed from alkali, and the steeping is repeated with 
 a weaker alkaline solution. The colouring matters, accompanied by some 
 impurities, are precipitated from the alkaline solution by an acid. This pre- 
 cipitate having been collected on a filter, washed, pressed, and dried, is 
 exhausted by boiling alcohol, and the filtered alcoholic solution precipitated 
 with water. A similar mode of proceeding has been proposed by M. 
 vSchutzenberger, with this difference, that he applies phosphate, or preferably, 
 pyrophosphate, of soda instead of carbonate, thus obtaining a pure colouring 
 matter. Good extracts of madder may be obtained by treating either 
 garancin or flowers of madder with — (a) boiling acetic acid, sp.gr. ro6o, 12° Tw. 
 The hot filtered liquid deposits, on cooling, abundance of a red flocculent 
 matter ; (b) by means of hot glycerin, which dissolves the colouring matters 
 and deposits them on cooling ; (c) by means of boiling benzin or rectified 
 boiling sulphide of carbon, best applied under pressure with special provision 
 against explosion and ignition ; (d) by means of a boiling acidulated solution 
 of alum, which dissolves the colouring matter, and throws it down on cooling. 
 It is quite clear that none of these methods are commercially available in con- 
 sequence of the expense and labour required. 
 
 We have now to mention some processes wherein water is used not to act 
 upon the pre-formed colouring matter, but upon their soluble glucosides 
 present in madder, which has not previously undergone any other operation 
 than mechanical trituration, and is not too old. Mr. Higgin treats freshly 
 ground madder with water containing from 3 to 6 per cent of its weight of 
 acetate of lead and acetic acid, the lead salt being added with the view of 
 preventing fermentation of the glucosides. The solution is filtered after standing 
 for one hour; ammonia is added to the solution, which is thereby turned red ; 
 heat is applied, while a current of air is passed through to oxidise substances 
 present, after which chloride of calcium is added for precipitation. The 
 material thrown down is collected on a filter, washed, and decomposed by an 
 acid, when the colouring matter is separated from the lime salt. A far more 
 generally applicable method is that devised by M. E. Kopp, who applies 
 sulphurous acid in aqueous solution; this solution, made in the usual manner, 
 should contain from 4 to 5 or 5$ thousandths of sulphurous acid. If the 
 water is pure (relatively free from calcareous matter) there is added to this 
 solution about from | to -r^^h °f hydrochloric acid, in order to saturate the 
 small quantity of carbonate of lime present even in the Alsace madder. If the 
 water contain calcareous matter in larger quantity, more hydrochloric acid is 
 required. The madder to be operated upon by this sulphurous acid solution 
 should neither be pulverised too finely nor be simply coarsely broken up. In 
 the first case filtration and expression are rendered more difficult, and in the 
 latter the action of the liquid becomes unequal, and the operation of squeezing 
 out is rendered almost impracticable. The madder is mixed with from ten to 
 twelve times its weight of the sulphurous acid solution, placed in wooden tubs 
 closed with tightly fitting covers, and left standing for from twelve to twenty- 
 five hours, care being taken to stir the magma now and then. The semi-fluid 
 mass is poured into a stout linen bag, and the tub rinsed out with a little clean 
 water, which is added to the magma in the bag. The liquid is allowed to run 
 
fir*^ 
 
 
 BBB 
 
 266 
 
 DYEING AND CALICO PRINTING. 
 
 off freely, and the bag gradually but strongly pressed ; the clear fluid collected 
 in a wooden tub; the contents of the bag are again placed in the tub from 
 which they were first removed, and again treated with ten times their weight 
 of sulphurous acid solution, and the yield added to the first obtained liquid. 
 This operation is once more repeated, but the liquid is employed as an 
 addition to the sulphurous acid solution required for a fresh portion of madder. 
 The liquids run off should be carefully kept from contadl of air, and poured 
 into tubs closed with tight-fitting wooden lids. The madder, which has been 
 exhausted with cold or tepid sulphurous acid, is placed in a vessel provided 
 with a false bottom, pierced with small holes, over which is laid a stout 
 piece of coarse flannel. The material is thoroughly washed out first with 
 warm and then with boiling water. It now constitutes a weak fleur de 
 garance, which yields on dyeing very pure tints, and leaves the whites 
 thoroughly unsoiled. By adding from 3 to 5 per cent of sulphuric or hydro- 
 chloric acid to the sulphurous acid solution, and heating to 50 or 6o°, a pre- 
 cipitate of raw purpurin is obtained, which is colleded, washed with cold 
 water to remove all the acid, and next dried. The remaining liquor, from which 
 the purpurin has been removed, is boiled, when carbonic acid is disengaged, 
 and a blackish-green pulverulent matter is thrown down, which is alizarin, 
 stained with a very dark green substance, a produdl of decomposition of 
 chlorogenin. The liquid should be kept at a boil for fully two hours in order 
 to ensure the complete precipitation of all the raw or so-called green alizarin. 
 The green alizarin is completely thrown down, and settles in from twenty- 
 four to thirty-six hours. Since it is in a' very fine powder it clings to the 
 sides of the vessel, and only falls to the bottom on agitation. The supernatant 
 liquid is run off, and the alizarin thrown upon a stout canvass filter, and 
 thoroughly washed with cold water. When the boiling process has been 
 carried on sufficiently long^the dark yellow mother-liquor does not contain any 
 more utilisable colouring matter. The alizarin is washed until all the acid is 
 thoroughly removed. The crude material thus obtained is a most excellent 
 dye stuff, readily manageable in the dye-beck, and yielding full bodied, very 
 bright, yet deep colours, thoroughly fast and resisting cleansing and boiling 
 soap lyes. The whites are scarcely soiled. Sometimes a small addition of 
 chalk (o - i to 0*2) is advantageous in the dye-bath. 
 
 Several processes have been proposed to obtain pure alizarin from this, 
 but none are readily practicable on the large scale, owing to the expense of the 
 solvents, and from the difficulty of separating the impurities from large 
 quantities of alizarin. The following process is the best and quickest : — 
 1 part of the raw alizarin is boiled with from 15 to 20 parts of light petroleum 
 oil, boiling at about 150 . After about fifteen minutes' boiling the vessel is 
 taken from the fire, and after standing for a few minutes, the clear liquid is 
 decanted from the sediment. As soon as the decanted liquid cools it deposits 
 a quantity of pure alizarin. When.- the temperature of the decanted fluid 
 has fallen to ioo°, there is added with careful stirring about 10 to 15 per cent 
 of a solution of caustic soda, containing from 5 to 8 percent of solid hydrate of 
 soda. The soda takes up all the alizarin, yielding a purplish-coloured solution. 
 The alkaline liquid is separated by decantation from the petroleum oil, and 
 supersaturated with dilute sulphuric acid, which causes the precipitation of 
 the alizarin in the shape of a crystalline magma, which is washed and dried. 
 
MADDER. 
 
 267 
 
 The petroleum oil is next again applied to the same purpose; three or four 
 treatments as described are sufficient to exhaust all the alizarin ; the re- 
 maining greenish-black mass can be utilised for the preparation of a peculiar 
 colouring matter (xanthazarin*), which possesses some curious properties. 
 The pulverised greenish-black matter is gradually and cautiously introduced 
 into a mixture of nitric acid with 10 parts of water heated to ioo°, care being 
 taken to avoid too strong action, and the quantity of the material being 
 adjusted to three-fourths of the weight of the nitric acid employed. A 
 brownish-yellow matter hardly soluble in water is obtatned. This xanthazarin 
 is sparingly soluble in boiling water, very soluble in alcohol and ether, 
 yielding a deep yellowish-brown coloured solution ; with aqueous solutions of 
 the caustic and carbonated alkalies it yields a very rich and brilliant orange 
 solution. It dyes woollen and silken fibres very readily even without 
 mordants, producing a deep golden-yellow colour. Cotton mordanted with 
 alumina and dyed with this material -assumes an orange-yellow colour. 
 Reducing agents, viz., nascent hydrogen, sulphuretted hydrogen, hyposulphites, 
 the protochlorides of tin and iron, deoxidise xanthazarin, and convert it into a 
 red colouring material, which yields upon mordanted silken, woollen, and cotton 
 fabrics colours approaching those produced by impure purpurin. Wool, pre- 
 viously dyed with xanthazarin a golden-yellow colour, assumes, when placed in 
 a boiling solution of tin-salt, a carmine-red colour. The colouring material 
 obtained by the reduction of xanthazarin is almost insoluble in water, and the 
 shades it produces on textile fabrics are faster than those of the unreduced 
 substance, which, however, stand ordinary washing. 
 
 M. Camille Kcechlin was the first to suggest that alizarin might be directly 
 obtained from madder by sublimation. The volatility of alizarin is, however, 
 not very great, and its sublimation point is too near that of its decomposition 
 by heat to make it practicable to sublime it from either madder, garancin, or 
 fieur de garance, while if it were possible to overcome this difficulty an enor- 
 mous quantity of empyreumatic matters would accompany the sublimed 
 product, rendering its further purification troublesome and expensive. M. C. 
 Kcechlin and afterwards M. E. Kopp have endeavoured to obtain alizarin from 
 madder or garancin by the aid of superheated steam. The apparatus employed 
 by Kopp for this purpose, represented in the annexed woodcut, consists of — 
 a, a steam boiler, b, steam pipe leading to B, a furnace for superheating the 
 steam which enters by d ; it leaves by e, a tube fitted with a stopcock, h. 
 F, spherically shaped chamber, divided internally into two compartments by 
 means of a perforated diaphragm, shown by a dotted line, and placed there to 
 admit of a thorough admixture of the superheated with the ordinary steam, 
 which latter is admitted by opening the stopcock g more or less. »', thermo- 
 meter, c c, copper cylinder for containing dry garancin placed between two 
 
 * Whilst madder root has been the object of a vast amount of research, the leaves, stem, 
 seed, and that woody matter which intervenes between the root and the parts just named 
 has been very iittle investigated. Many intelligent madder growers, both in Zealand and 
 France, hold that the colouring principles are developed in the parts above ground, and re- 
 turned to the root there to undergo further elaboration. Experiments have been undertaken 
 to determine this question. Though these were never completed, it appears that the stems 
 and seeds contain a substance closely related to xanthazarin. The first indications of alizarin 
 in the plant are found about 1 inch below the soil. The woody part of the stem contains 
 neither alizarin nor purpurin. 
 

 268 DYEING AND CALICO PRINTING. 
 
 diaphragms ; this cylinder receives steam (is in communication with the vessel 
 F by means of the tube containing the stopcock k). D, another cylinder, serving 
 as envelope for the last mentioned, and also in communication with f by means 
 of a tube fitted with the stopcock /, which on being opened admits steam to d, 
 the excess of which escapes by m. h, condensing apparatus, into which the 
 products of the distillation are admitted by means of the tube/, which com- 
 municates with c c. When the furnace for superheating the steam has been 
 heated to 360°, steam from the boiler at 180 (= 10 atmospheres, or 150 lbs. 
 pressure to the square inch) is admitted into the cylinder D, and as soon as the 
 cylinder c c and its contents have acquired that temperature the stopcock k is 
 opened, by means of which superheated steam is admitted, first at a tempera- 
 ture of 200 , increasing gradually to 220°, 230°, and at last to 240 . The 
 alizarin is volatilised, and carried by the steam in the shape of an orange- 
 yellow coloured gas, which on condensing exhibits a powder of the same 
 colour. When the operation is finished this powder is collected on a filter, 
 while the condensed steam can be applied for dyeing purposes. 
 
 Fig. 21. 
 
 Madder lakes are insoluble combinations of the red colouring matters of 
 madder with certain metallic oxides. Some of these are of great beauty, and 
 employed by artists as oil and water colours, and they may be fixed upon textile 
 fabrics, by the intervention of albumen, in the same lnannei as ultramarine, 
 or they may be applied by being dissolved in a proper vehicle, say acetic ac id, 
 and thus used for calico-printing, because on expelling the solvent by steamiing 
 the pigment is fixed. 
 
 The only madder lakes which have obtained extensive application are those 
 of alumina, the alizarate and purpurate. They are a more or less deep ro>se, 
 with a slight — yet distinct and very characteristic — bluish hue. It is not easy 
 to obtain really deep red coloured madder lakes in a dry state, owing to tthe 
 great difficulty of obtaining alumina free from iron. These pigments yield 
 fast colours, and are on that account esteemed in calico-printing. The prin- 
 ciple of the preparation of these substances is that the madder pigments are 
 dissolved by alum solutions, and precipitated by means of carbonate of so>da. 
 The following is M. Persoz's process : — Madder is washed with cold water 
 
MADDER. 
 
 269 
 
 wherein some sulphate of soda is previously dissolved, and boiled for about 
 twenty minutes with ten times its weight of a solution of alum containing 
 10 per cer»t of that salt as free as possible from iron. The liquid is filtered 
 off from the insoluble dregs, and cooled down to 40 or 35 . The red-coloured 
 solution can be treated either (1) by saturating cautiously with carbonate of soda 
 equal to from one-eighth to one-tenth of the weight of alum used, so as to 
 cause the formation of a basic alum to remain in solution. By bringing this 
 fluid to a boil an insoluble subsulphate is thrown down, carrying along with it all 
 the colouring matter contained in the solution: This precipitate is not gela- 
 tinous, separates readily, and is easily filtered ; it is, moreover, entirely soluble 
 in acetic acid. (2). By adding to the solution a suitable quantity of acetate 
 of lead (78 parts of that salt for every 100 of alum employed), when sulphate 
 of lead is precipitated. The red-coloured liquid, having been filtered, is 
 boiled, when a basic sulphate of alumina is thrown down, combined with all 
 the colouring matter in solution. The lake thus obtained is far deeper and 
 more beautiful than that prepared with carbonate of soda. Instead of madder 
 many of its commercial preparations can be applied for this purpose ; among 
 these may be noted purpurin. 
 
 It is quite clear that the preparation of madder lakes may be conducted by 
 various other processes ; for instance, the colouring matter could be dissolved 
 in a limited quantity of alkali, and this solution saturated with hydrate of 
 alumina. Hitherto the preparation of an iron lake from madder, suitable for 
 printing purposes, has not succeeded. En passant, we mention here that 
 alizarin ink is largely made in Germany ; it is, of course, washed madder 
 which is used for this purpose : it is intensely black, and very valuable, inas- 
 much as it is very fast and suitable for steel pens. 
 
 Testing of Madders, Fleur de Garance, Garancin, Extracts, &c. 
 
 We have already shown that a very large number of variable conditions 
 exert, in some way or other, an influence upon the richness of any given kind 
 of madder, in colouring material and the fastness of the colours produced. 
 Sometimes madder is purposely adulterated with substances either. added to 
 increase the weight or with organic matters of no tinctorial value at all. 
 Three points have to be kept in view for properly testing madder, viz. — (1), the 
 value of the substance for the consumer under the conditions in which it is 
 employed by him — a value depending upon the utilisable quantity of tinctorial 
 matter present and upon the fastness and purity of the dyes produced upon 
 the fabrics ; (2), the absolute quantity of colouring matter present in the 
 powder; (3), the testing for and quantitative determination of foreign and 
 inert substances. Since the first point has the greatest interest to the consumer, 
 it has been most studied, and we owe to M. H. Schlumberger a most practical 
 — and at the same time most complete — process for its proper manipulation. 
 
 M. Schlumberger's process for estimating the utilisable tinctorial value of 
 any kind of madder or garancin, and the test for the fastness of the colours 
 produced, may be summarised as follows : — The principle of this mode of 
 testing is a dyeing experiment, with a known quantity of madder and a known 
 square surface of mordanted tissue, prepared — as used on the large scale — for 
 red, rose-colour, and pink, with alumina mordants, and for black, lilac, and 
 purple, with iron mordants. The result is compared with the effects produced 
 

 270 
 
 DYEING AND CALICO PRINTING. 
 
 by a standard sample of madder of good quality. It is well to have an ample 
 stock of that standard sample on hand, and to make simultaneously an 
 experiment with it, while it is also advisable to weigh off at least two quantities 
 of each sample to be tried, and experiment upon them at the same time. The 
 relation between the mordanted surface of tissue and the tinctorial matter 
 should be so regulated that the mordant be not quite saturated, so as to leave 
 room for the evaluation of dye material, which perhaps might be better than 
 the standard. On the other hand, the degree of saturation must be such as to 
 admit of the proper estimation of the liveliness of the colours produced, and 
 their fixity as regards the process of avivage or clearing : this latter operation 
 is the more required to be performed with these samples, since it often brings 
 the colours out in a manner different from their primitive brightness and 
 intensity. The quantity of tissue — usually cotton — to be used in each expe- 
 riment is 25 square centimetres, properly mordanted, and so treated as to be 
 quite ready for use.* The quantity of madder is 10 grms., and of fleur de 
 garance 5 grms., with a quantity of 1 litre of distilled water. When the 
 experiment is to be made with Alsace madder, a little chalk has to be added 
 to the water. The weighing off of the sample should be correct at least within 
 1 centigramme. The apparatus to be used and the manipulations to be 
 employed are as follows : — The samples of cotton which are marked by slits at 
 the margin, and the madder are placed in cylindrical glasses, capable of holding 
 at least 1*2 litres, and made of well-annealed glass. These are placed together 
 in a large copper, the top being closed by a copper lid, perforated with cylin- 
 drical openings large enough to admit the glasses to reach into the water. 
 The best plan is to make the glass vessels rest on a perforated false bottom, 
 and to immerse them to such a depth that only about £ an inch projects out 
 at the top. The glass vessels should not be placed in the water-bath until its 
 temperature is 25 . At least two thermometers should be at hand : one to 
 ascertain the temperature of the water-bath, the other to test now and 
 then the temperature in the glass vessels. The heat is slowly raised from 
 25 to 95 during the lapse of two hours. t The latter degree is kept up for half an 
 hour. It is very essential that a glass rod, not too thin, should be placed in 
 each glass vessel, and the contents stirred every five minutes, care being taken 
 to keep the cotton tissue entirely immersed and below the surface of the 
 liquid. Every quarter of an hour the thermometer should be applied, to test 
 the degree of heat inside each vessel : after the lapse of two and a half hours 
 the pieces of tissue are removed from the baths, rinsed in cold water to remove 
 adhering particles of madder or dye-stuff, then washed in cold water, squeezed 
 out, dried, and ironed with a smoothing-iron as used by laundresses, and next 
 cut with a pair of scissors in two equally sized parts, one of which is kept 
 without further treatment, while the other is submitted to avivage or clearing. 
 The first portion is pasted with one edge to a piece of paper, an open space 
 being left for the other half to be pasted in afterwards. The first pattern of 
 
 * On the Continent, in France and Belgium, tissue thus ready prepared and mordanted, in 
 the shape of stripes running parallel with the width of the cloth, and ready for red, pink, violet, 
 lilac, &c, is sold in several of the larger towns. 
 
 Where steam can be had it is best to apply that to heat the water, since it is more easily 
 regulated than open fire : in the latter case charcoal and peat answer better than coals ; gas 
 of course, may be applied where it is to be had, 
 
MADDER. 
 
 271 
 
 each sample is intended to exhibit the intensity of the tints produced before 
 clearing, and also the degree of purity of the whites. 
 
 The process of avivage or clearing is carried on as follows : — (1), the samples 
 are left for half an hour in a soap bath, made up — for eight samples of the 
 size above stated — of 10 grms. of medium white soap and 4 litres of water, at 
 a temperature of 75°; (2), boiling for half an hour in a soap bath of the com- 
 position just mentioned ; (3), washing in cold water (that is to say, water of 
 the same temperature as that of the place where the experiments take place) ; 
 (4), the samples are next placed for ten minutes in a bath made up of 
 5 grms. of soap and 5 grms. of nitro-muriate of tin, in 4 litres of water at 45 . 
 From this they are immediately transferred to a bath of boiling soap-water, — 
 10 grms. of soap to 4 litres of water, — and kept boiling for half an hour. 
 Next they are washed in cold water, dried, and ironed. By this process the 
 solidity or fastness of the colours and their brilliancy may be judged. 
 
 M. G. Schaeffer observes, as regards fleur de garance, that, since its use 
 has become general, the tinctorial value of that material has in many cases 
 been lowered. Fleur de garance is often met with which contains appreciable 
 quantities of soluble organic matter and of sulphuric acid. It is quite evident 
 that such produces cannot possibly yield good results in dyeing, and among 
 the tints which suffer most is the purple. The same authority states that the 
 results obtained in testing fleur de garance do not represent so well as in case 
 of madder the results obtainable on the large scale, especially when the 
 sample is not well prepared, because the quantity of water used by the expe- 
 riments on the small scale is about eight times larger than the quantity used 
 on the large scale. Hence it is evident that the injurious effects of acid and 
 of soluble matters present are less manifest in the experiments upon the small 
 scale than in actual working. It is therefore required to test fleur de garance, 
 previous to the dyeing experiment, for soluble matters. This is done as 
 follows : — A quantity of some 10 to 15 grms. is thoroughly steeped in cold 
 water, and the solid substance collected on a filter and washed. If the liquid 
 which runs off is perceptibly coloured it is quite certain that the fleur de 
 garance is not of the best quality. If chloride of barium produces this 
 aqueous solution, which must be previously acidulated with a few drops of 
 pure hydrochloric acid, a precipitate of sulphate of baryta will appear, indi- 
 cating bad preparation. Such samples yield, when heated with sulphuric or 
 hydrochloric acid, a very marked green colouration. 
 
 Fleur de garance, when properly prepared and carefully manufactured, gives 
 hardly any colouration to cold water, and neither renders it acid nor capable of 
 precipitating salts of baryta. If the sample is treated with sulphuric acid a 
 rose colour is produced, and with hydrochloric acid a yellowish colouration. 
 
 It is best, when dyeing experiments are made with fleur de garance, to 
 take of every sample two weighed quantities, and to add to one of these about 
 one-fifth part of its weight of chalk, and leave the other sample to be operated 
 upon without such addition. It is to be observed, also, that whereas with 
 madder the temperature must be kept gradually rising, and neither falling nor 
 remaining stationary, an irregularity of this kind is of no consequence with 
 fleur de garance, while any irregularity with madder spoils the experiment. 
 For 25 square centimetres of mordanted cotton tissue, as above specified, 
 16 grms. of garancin and | litre of water are taken ; in half an hour the 
 
H39SEH WWMWH MMWUM JWgH MWWH H y 
 
 272 DYEING AND CALICO PRINTING. 
 
 temperature is raised from 25° to go ; afterwards the sample of cotton is first 
 rinsed in cold and next washed in hot water, dried, and ironed. The same 
 dyeing process as above described can be applied to test the value of extracts 
 of madder, green alizarin, &c, with this understanding — that not only the 
 quantity of such materials, but also of water, has to be modified. Resinous 
 extracts should be first dissolved in a small quantity of alcohol, whereby the 
 solution of colouring matter in the bath is promoted. As a general rule, the 
 quantity of water to be employed in the process has to be decreased within 
 certain limits, according to the higher degree of concentration of the tinctorial 
 substance. For instance, with an extract from sixteen to twenty times 
 stronger than madder, 250 cubic centimetres — } litre — of water is sufficient 
 for a surface of 25 square centimetres and the proper dose of dye material. 
 
 It is easily perceived that the process of test dyeing just described only 
 yields results which can be compared with a standard sample, but the utility 
 of this process is enlarged when dyeing experiments are made with decreasing 
 quantities of the standard sample, the quantity — or rather size — of the cotton 
 remaining the same. It is evident that — starting with 10 grms. of madder, 
 5 grms. of fleur de garance, and i-6 grms. of garancin — a set of dyed samples 
 may be produced, the colours of which, before as well as after the avivage, 
 will be of less intensity, and we may thus construct a table or scale of colours, 
 taking fleur de garance, for instance, as follows : — 
 
 No. 1 5-00 grms. 
 
 No. 2 4-50 ,, 
 
 No. 3 400 „ 
 
 No. 4 3-50 „ 
 
 No. 5 3-00 „ 
 
 No. 6 2*50 ,, 
 
 and so on ; and when an experimental dyeing result made with 5 grms. of 
 fleur happens to be equal to between 2 and 3, we can say that 5 grms. of that 
 fleur have a tinctorial value of from 4-5 to 4 grms. of the standard sample, or 
 on average = 85, the standard being 100. 
 
 As regards the evaluation of the absolute quantity of colouring matter 
 present in madder, none of the very large number of methods proposed for 
 this purpose answer the object in view. These processes, moreover, are all of 
 so complicated a nature, and require such a series of manipulations, that they 
 are of no use whatever for practical work in dye establishments. M. Schlum- 
 berger has devised a method which gives satisfactory'approximative results, and 
 is based upon the dissolving power of acetic acid upon the colouring matter. 
 Take 10 grms. of madder, which place in a suitably shaped glass vessel, 
 e.g., a wide-mouth bottle ; add 500 grms. of distilled water heated to 30 , and 
 add a small quantity of beer yeast. Leave the mixture to ferment for twenty- 
 four hours at a suitable temperature ; filter off, and wash with distilled water, 
 acidified with one-fiftieth of its bulk of acetic acid. Instead of the fermenta- 
 tion process, we may steep the madder in water acidified with acetic acid, 
 for some hours, at 30°. Neither this operation nor that of fermentation is 
 necessary when fleur de garance is to be tested. The residue left on the filter 
 is boiled for ten minutes with a litre of very dilute acetic acid, — sp. gr. i - oo5, 
 or about 1° Tw., — and decanted, after some rest pouring the liquid on a filter, 
 
MADDER. 273 
 
 and boiling the residue again with a fresh quantity of the same acid. These 
 solutions deposit, on cooling, an orange-coloured flocculent matter, while 
 some remains in solution, which is best precipitated by means of chloride of 
 sodium. These sediments are carefully collected on a small dried and tared 
 filter, washed with distilled water, carefully dried, and weighed. 
 
 By means of this process M. Schlumberger has obtained from 100 grms. of 
 good madder (Avignon, Alsace, and Zealand) from 4-1 to 4-2 grms. of colouring 
 matter. Inferior kinds — that is to say, second quality of the same origin — 
 gave from 1*9 to 27 grms., while freshly-ground madder yielded from 3*8 to 
 4-2 grms. per cent, because, as regards the latter, the boiling with acetic acid 
 has the effect of splitting up the glucosides, thereby making them equally rich 
 in colouring matter as old madder. 
 
 The following mineral substances have been occasionally used to adulterate 
 madder: — Ground-up red bricks, red and yellow ochres, yellow sand, and 
 native coloured clays. Among organic substances the following have been 
 sometimes used : — Sawdust of dark coloured woods, ground-up almond-shells, 
 bran, fir-wood bark, logwood, santal wood, sapan wood, Brazil wood : as 
 regards the mineral matters these may be readily enough detected, by the 
 incineration of madder in a platinum crucible. It is best to take for that 
 purpose from 5 to 10 grms., and to bear in mind that the quantity of ash 
 (mineral matter) naturally present in madder varies from 5 to 9 per cent ; in 
 low class Mull madders it may reach 50. The qualitative testing of the ash 
 will suffice to detect any fraudulent admixture. 
 
 As regards the adulteration with organic substances, we quote M. Pernod's 
 plan for discovering their presence : — A piece of white paper is dipped for a 
 minute or so in a weak aqueous solution of bichloride of tin ; the sheet is 
 placed on a plate glass, or on a clean porcelain dish, and by means of a fine 
 gauze sieve a very small quantity of the pulverised madder is scattered on 
 the surface. After the lapse of about half an hour every portion of the paper 
 where a particle of the dye-wood has fallen will exhibit the following 
 colourations : — 
 
 For Brazil wood Carmine-red specks. 
 
 ,, Logwood Violet-coloured spots. 
 
 „ Fustic Yetlow-coloured spots. 
 
 ,, Genuine madder . . . . Faint yellow colouration. 
 If astringent substances have been added these may be readily detected by 
 means of a sheet of test-paper impregnated with a mixture of proto- and per- 
 salts of iron, and moistened with alcohol. This paper, strewed over with the 
 suspected madder in the manner as above, will, in case of adulteration, exhibit 
 blackish-blue specks wherever any astringent matter has fallen. Pure madder 
 yields in this instance only a bright brown colouration. The presence of 
 foreign dye-woods in madder can also be ascertained by testing a hot filtered 
 solution of madder with bichloride of tin or a per-salt of iron. 
 
 Use and Application made of Madder, and its Preparations for 
 Dyeing Purposes. 
 
 The red colouring substances present in madder — that is to say, those which 
 yield red colours with mordants of alumina — are its only really useful consti- 
 tuents. As regards the yellow and brownish matters, they only serve to 
 
 T 
 
. g&laF 
 
 
 IBBIWMWBMHMH 
 
 
 274 
 
 DYEING AND CALICO PRINTING. 
 
 complicate the dyeing operations, and to diminish the beauty of the colours. 
 These colouring substances do not admit of being directly fixed on textile 
 fibres, the intervention of a mordant being an absolute necessity. Most of 
 these mordants are metallic oxides, those chiefly used being the hydrated 
 oxides of aluminium, peroxide of iron, and the sesquioxide of chromium. 
 These oxides are incorporated with the fibre of the tissues by being brought 
 into contact therewith as soluble salts, when they are precipitated and fixed 
 in the fibre. The mordanted tissue, on being placed in a dye-beck containing 
 the dye stuff, attracts the colouring matter, and combines with it in precisely 
 the same manner as if the tissue were not present, — that is to say, that the 
 affinities are only exercised between the colouring matter and the metallic 
 oxide, while the tissue serves no other purpose than that of a framework in 
 which both are mechanically held. There is thus formed a coloured lake 
 adhering to the cloth, and the shade of colour, as well as its kind, varies with 
 the nature of the oxide applied. This is red, rose, or pink coloured, when 
 alumina is used ; black, violet, or lilac, with iron, and chocolate, when a 
 mixture of both these is made use of. Hence it follows that a dye-beck 
 containing one and the self-same dye stuff (say madder) will produce, upon 
 variously mordanted fabrics, very varying colours. In some cases a third 
 substance is employed along with the madder pigments and the mordant, viz., 
 a peculiarly modified fatty substance, as is the case in Turkey red dyeing, 
 where this body gives greater stability and brilliancy of colour to the compound 
 produced by the mordant and pigment. Generally the mordants are first 
 applied to the tissue. This may, of course, be done in such a manner as to 
 form designs and patterns by the aid of engraved rollers ; after which the 
 whole fabric is immersed in a dye-beck containing the madder, garancin, or 
 fleur de garance, as the case may be, and treated as if it were to be uniformly 
 dyed. 
 
 Madder colours are rarely printed directly on the fabrics. The use of madder 
 and of fleur de garance implies some other operations after the textile fabrics 
 leave the dye-beck, the aim of which operations is partly the bleaching or 
 whitening up of those portions of the tissue which are intended to be left 
 white, since it is not possible so to manage the dyeing process as not to soil, 
 more or less, the portions of the fabric where no mordant at all is applied. 
 On the other hand, the coloured portions have to be rendered bright and 
 brilliant by soaping and clearing, whereby the colours are freed from such 
 materials as would injure their beauty, viz., the yellowish substances present 
 in the dye materials applied. When garancin, pincoffin-, or any of the extracts 
 of madder are used, the process of soaping and clearing (avivagc) is not 
 needed to the same extent, and a slight treatment with chlorine is quite 
 sufficient to restore the purity of the white portions of the tissues. It should 
 be observed that the colours are then less brilliant, less full-bodied and deep, 
 than when madder is used and clearing employed. It depends, of course, upon 
 the choice of the manufacturer, and upon the peculiar destination of the goods, 
 whether madder, garancin, or fleur de garance is selected. When garancin or 
 commercial alizarin is used, catechu can be applied simultaneously if desired, 
 but this cannot be done with madder or fleur de garance, which require 
 avivage. 
 
 The ordinary madder dyeing operation for the production of red (exclusive 
 
MORDANTS. 275 
 
 of Turkey red), rose or pink, black, violet, and lilac of the highest brilHancy, 
 whether separately or conjointly, consists of the following separate manipu- 
 lations : — (1). Bleaching the calico so as to render it perfectly white. 
 (2). Printing the mordants dissolved in a proper vehicle, and suitably 
 thickened. (3). Fixation of the mordants — that is to say, the precipitation 
 of the oxides— on and in the pores of the textile fibres. (4). Dyeing operation 
 (garangage). (5). Aviv age, or purification of the colours produced in the dye- 
 beck : this may perhaps be designated as the process of modification of the 
 colours by the introduction thereinto of a certain quantity of a fatty substance 
 from the soap, and of oxide of tin from the salt of tin. 
 
 A. Bleaching.— We have previously entered into the details of this opera- 
 tion. What is especially required for this purpose is, that the operation shall 
 be so perfectly performed that no foreign substance left in the tissue may, on 
 the fabric being placed in the dye-beck, absorb so much of the colouring 
 matter as to render the elimination thereof afterwards either impossible 
 or impracticable. 
 
 B. Printing and Fixing the Mordants.— The operation of printing is a 
 purely mechanical process, performed by highly complex machinery, the 
 description of which is entirely beyond the scope of this volume. The sub- 
 stances used as mordants, and the methods whereby they are fixed, require 
 our particular attention. 
 
 Mordants for Red-Pink, Rose-colour. 
 
 The substance used for this purpose is either a hydrate or a sub-salt of 
 alumina. This material has to be intimately united with the fibre. 
 
 Alum is composed of sulphate of alumina and sulphate of potassa combined 
 with water. There are two kinds of alum used in the arts. The greater part 
 of the alum now met with in commerce, excepting what is yet made in the 
 Papal States near Rome, is ammonia-alum. For the uses to which this salt is 
 applied it is quite indifferent which of these two kinds is taken : the ammonia- 
 alum is slightly more advantageous in strength. There are some cases where 
 ammonia-alum cannot be applied, and where alum absolutely free from 
 ammonia is required for use. By external appearance there is no possibility 
 of distinguishing ammonia- from potash-alum ; but if the sample is mixed up 
 with caustic soda or slaked lime, ammonia-alum gives off the well-known 
 pungent smell of ammonia. Alum in large crystalline lumps is more likely to 
 be pure than that which is sold in powder, which often contains a small per- 
 centage of mother-liquor in excess, and more frequently traces of iron. Iron is 
 the only impurity likely to cause trouble in alum : sometimes it is present in 
 such quantities as to cause serious injury. As a test for iron, logwood liquor, 
 tincture of galls, or a solution of ferro- and ferri-cyanide of potassium may be 
 used. M. Persoz recommends, as a reliable test, the addition first of an excess 
 of tartaric acid to the alum, and then caustic potassa in excess, when, a drop 
 of sulphide of ammonium being added, the minutest trace of iron gives a 
 black colour. 
 
 Potash alum (KO,S03-f-Al20 3) 3SO3 + 24H0) consists of potash, 9*95 per 
 cent ; alumina, iO'83 ; sulphuric acid, 3371 ; water, 45 , 5i. At 6o° C. it loses 
 18 equivalents of water; fuses at 92 in its water of crystallisation, but is 
 
 t 2 
 

 276 
 
 DYEING AND CALICO PRINTING. 
 
 only deprived of its entire quantity of water a little below red heat. Its 
 solubility in water varies considerably, according to the temperature : — 
 100 parts of water at 0° dissolve 3-39 parts of alum. 
 ,1 „ 2o 9 „ 15-13 „ 
 
 4°° - 3°"92 „ 
 11 11 ioo° „ 357'4 8 » » 
 
 The solution of alum has a sweetish astringent taste, and exhibits an acid 
 reaction. A concentrated aqueous solution of alum destroys the blue colour 
 of ultramarine. 
 
 Ammonia-alum (NH + 0,S0 3 + Al 2 3 ,3S0 3 + 24HO) contains ammonia, 3-89 
 percent; alumina, 11-90; sulphuric acid, 36-10 ; water, 48-11. 
 
 100 parts of water at 0° dissolve 5-22 parts of this kind of alum. 
 „ ,, 20 „ 13-66 ,, „ „ 
 
 11 .» 4°° -» 2 7' 2 7 » 11 » 
 
 ,, ,, ioo° ,, 421-90 ,, „ n 
 
 When ammonia-alum is strongly heated, sulphate of ammonia, water, and 
 sulphuric acid are driven off, while pure alumina is left behind : this property 
 may, of course, be readily applied as a test. 
 
 Neutral or cubical alum (KO,S0 3 + A1 2 3 ,2S0 3 ) is obtained when 12 parts 
 of alum and 1 part of slaked lime are boiled in water : on cooling, cubical- 
 shaped crystals are deposited, which are valued in dyeing operations on 
 account of their freedom from acid. The composition of such an alum is — 
 Sulphuric acid, 33-95 ; alumina, 11-40 ; potash, 9-04 ; water, 4561. 
 
 Sulphate of alumina — also known as cake alum, patent alum, and concen- 
 trated alum — is a salt manufactured on the large scale by dissolving previously 
 calcined alumina (a pure clay, as much as possible free from iron) in concen- 
 trated sulphuric acid, the quantity of which is so regulated that there is rather 
 excess of alumina. The formula of this salt is Al 2 3 ,3S0 3 + i6HO. Not- 
 withstanding yellow prussiate of potassa is purposely used for purifying this 
 salt from iron, it is often found to contain some of that metal, and it is not 
 unfrequently contaminated with Prussian blue. As regards its use in dyeing 
 and calico-printing, it makes good red liquors, the technical name for those 
 alumina mordants which yield red dyes with madder. It is stronger, weight 
 for weight, than alum, containing at least a third more alumina, and conse- 
 quently going further; but its composition is not constant, and the experience 
 of all practical dyers and printers is that, although its use effects a saving of 
 one-fourth of acetate of lead in the preparation of acetate of alumina, it is 
 not by any means a suitable substitute for alum (potassa or ammonia), since 
 it has been found that acetate of potassa and acetate of ammonia are of real 
 use in the mordanting process : it is, moreover, by no means so easy an 
 operation to get sulphate of alumina quite free from iron. According to 
 Wildenstein, some of it contains even as much as 11 per cent of sulphate of 
 protoxide of iron. 
 
 Nitrate of alumina and muriate or hydrochlorate of alumina (chloride of 
 aluminium) are sparingly employed : they are made by mixing, in the first 
 case, alum and nitrate of lead; and in the second, alum and chloride of cal- 
 cium, known also as muriate of lime in the trade. Nitrate of alumina is 
 easily decomposed, parting with its acid at a comparatively low temperature. 
 
MORDANTS. 
 
 277 
 
 Some of the uses of nitrate of alumina depend more on its acting as a conve- 
 nient acid salt than as an aluminous compound : thus it is used in blocking 
 upon chrome oranges, to change them into yellow : its utility, in some steam 
 colours, seems to be referable to the oxidising action of the nitric acid upon 
 the colouring matter. On account of this ready splitting up of the elements 
 of nitrate of alumina into acid and base, it must be sparingly and cautiously 
 used as an ingredient in printers' colours. Chloride of aluminium, or muriate 
 of alumina, resembles the nitrate with regard to stability, its solution acting 
 nearly as powerfully as an acid, as if no alumina were present to neutralise 
 the acid contained. 
 
 Acetate of alumina, or red liquor, made by mixing together acetate of 
 lead and sulphate of alumina, or alum, is a very important mordant. When to 
 a concentrated solution of sulphate of alumina a solution of acetate of lead 
 is added, there is formed a precipitate of sulphate of lead, while the resulting 
 liquid retains some of that salt in solution, which is got rid of by the aid of 
 sulphuretted hydrogen and acetate of baryta. The solution of the acetate of 
 alumina so obtained smells so strongly of acetic acid that it seems as if a 
 portion only of the acetic acid had entered into chemical combination with 
 the base. If spread out in thin layers, on plates of glass or porcelain, and 
 heated to 37 , care being taken to keep the fluid constantly stirred, the salt 
 dries up to a gum-like mass, easily re-soluble in water, but not exhibiting any 
 longer the slightest smell of acetic acid. This product is considered by 
 Mr. Walter Crum as a biacetate, while the liquor just alluded to is considered 
 to be a mixture of acetic acid and this biacetate in aqueous solution. The 
 solution of gelatinous alumina in boiling acetic acid, applied in excess, also 
 yields the acetate here alluded to. The strongest solutions of saturated 
 acetate, obtainable by double decomposition, contain about 5 per cent of 
 alumina. When that solution, or also the solution obtained by dissolving 
 alumina in boiling acetic acid, is left for several days standing at a temperature 
 of 15 to 20°, it deposits on the sides of the vessel a solid substance, which 
 after drying has the appearance of porcelain ; and its composition is, according 
 to Mr. Walter Crum, an insoluble biacetate containing five molecules of water. 
 Another insoluble biacetate is obtainable in the shape of a crystalline precipi- 
 tate. When a concentrated solution of red liquor, as first obtained by double 
 decomposition, is heated, the supernatant liquid is almost entirely freed from 
 alumina. The solutions of acetate of alumina obtained by double decompo- 
 sition, and containing less than 3 per cent of alumina, are not precipitated by 
 ebullition when they are freshly prepared, but after having been left standing 
 for some weeks they acquire this property as soon as they contain as much 
 free acetic acid as is equal to that contained in a saturated solution of acetate 
 of alumina containing 4 per cent of alumina. When to red liquor such salts 
 as, for instance, sulphates of soda, potassa, ammonia, magnesia, common 
 salt, or alum, are added, they become far more readily turbid by the action of 
 heat than when pure ; but the solution of pure acetate of alumina is precipi- 
 tated, — that is to say, becomes decomposed, and a basic salt thrown down — 
 when heated to ioo°, while acetic acid is set free : the precipitate thus formed 
 is re-dissolved on cooling, if care has been taken not to apply the heat so long 
 as to expel the acetic acid which was set free. 
 
 Red liquor prepared with alum and acetate of lead, instead of sulphate of 
 

 278 
 
 DYEING AND CALICO PRINTING. 
 
 alumina, consists of a mixture of acetate of alumina and an alkaline sulphate, 
 and hence this preparation is more readily decomposed by heat than the pure 
 acetate, which requires longer boiling and a certain degree of concentration. 
 
 For the preparation of neutral acetate of alumina, by means of alum and 
 acetate of lead, 100 parts of the last-named salt require 62 - 6 of alum for com- 
 plete decomposition, but very frequently in practice alum is applied in slight 
 excess. 
 
 In Germany, a solution of alum is very frequently first converted into inso- 
 luble (basic) alum by means of carbonate of soda, and the resulting salt 
 dissolved in acetic acid. Acetate of alumina is usually made by the com- 
 sumers, who often employ, instead of acetate of lead, the cheaper acetate of 
 lime for the purpose of double decomposition, or also acetate of soda. Some- 
 times red liqucr is purposely mixed with such salts as chloride of zinc, common 
 salt, or chloride of ammonium, for the purpose of preventing the too rapid 
 drying up of the acetate on the textile fibres. Acetate of alumina is also 
 applied, on the large scale, to render woollen fabrics water-tight. If acetate 
 of lead be mixed with alum and hot water, and cotton cloth then passed in it, 
 it takes up alumina in sufficient quantity to dye with. In mordanting woollen 
 cloth, cream of tartar (bitartrate of potassa) is used to mix with the alum, and 
 here a similar decomposition takes place ; the sulphuric acid goes to the 
 potassa, leaving the tartaric acid to the alumina, from which the wool can take 
 it up easily. The acetate of alumina does not answer so well for woollen 
 fabrics as the tartrate, perhaps because it gives up its alumina too readily, 
 whereby the mordanting is rendered superficial and uneven. 
 
 Aluminate of potassa is known as alkaline pink mordant. Alumina, in 
 the hydrated gelatinous state, is readily soluble in caustic alkalies. If caustic 
 potassa is added to a clear aqueous solution of alum, with the precaution not 
 to overdose the alkali, there is at first precipitated gelatinous hydrate of 
 alumina, which re-dissolves on adding more alkali. On the large scale this 
 solution is made by taking a sufficient quantity of a solution of caustic 
 potassa, sp. gr. 1*307 to i - 4i = 40 to 50° Tw., and heating nearly to boiling 
 in an iron pan. The requisite quantity of alum or sulphate of alumina, in 
 coarse powder, is put in by degrees, the heat of the liquid being kept up, and 
 the whole well stirred. Finally, it should be boiled a short time, say fifteen 
 minutes, and then allowed to cool. Crystals of sulphate of potassa are depo- 
 sited, which are very sparingly soluble in the alkaline liquid. Another sediment, 
 of a light colour, is found at the bottom of the pan, consisting of alumina not 
 dissolved. About 34 lbs. of alum to a gallon of caustic lye, at 40 Tw., is a 
 proper proportion : if sulphate of alumina be used the same quantity may be 
 taken, but the caustic liquid should be more concentrated, ranging from 50" to 
 55 Tw. Practical experience has taught that ammonia-alum will not answer 
 for this purpose, since more caustic lye is required to drive off the ammonia. 
 Alumina hydrate may be made first, and then dissolved in caustic lye. This 
 is a more scientific as well as a more economical method, since no alkali 
 would then be required for combining with the sulphuric acid of either alum 
 or sulphate of alumina. 
 
 Aluminate of potassa should be kept in a covered vessel, since it is injured 
 by lengthened exposure to air: it is preferably kept in vessels made of iron, 
 since it attacks glass, earthenware-jars, and wood. The addition of acids or acid 
 
MORDANTS. 
 
 279 
 
 salts to this solution causes precipitation of the alumina. The carbonic acid 
 of the air also slowly causes the decomposition of this liquor, especially if it 
 is exposed in thin layers : most of the neutral salts, when mixed with this 
 fluid, precipitate the alumina, as, for instance, sal-ammoniac, the sulphates of 
 magnesia and zinc, and all other soluble metallic salts. This reaction is made 
 use of in the process of mordanting with aluminate of potassa, since the cloth 
 previously impregnated with this liquid is dunged, with the addition of some 
 of these salts to fix the alumina, sal-ammoniac or a salt of zinc being pre- 
 ferred. The oxide of zinc simultaneously precipitated has very little affinity 
 for the cloth, and is detached in washing, but any iron salt present is decom- 
 posed and deposited in the fibres along with the alumina, and, according to 
 the quantity present, it dyes up with madder a dull chocolate instead of red. 
 
 Aluminate of soda is largely made and used in France, since the discovery 
 of the extensive deposits of bauxite in the southern parts of that country. 
 It is obtained by roasting, in a reverberatory furnace, a mixture of soda-ash 
 and bauxite, until a small sample taken from the fritted mass ceases to 
 effervesce with acids. When the operation is finished, the aluminate of soda 
 is extracted by lixiviation with boiling water, and the solution evaporated to 
 dryness. It is a coarse powder, exhibiting a slightly greenish colour, due to a 
 trace of vanadium. It is infusible at the highest furnace-heat, and readily 
 soluble in hot and cold water. Dilute solutions (sp. gr. 1*072 to 1*089 
 = 14 and 17 Tw.) remain limpid and clear for a long time, but stronger solu- 
 tions (sp. gr. 1*3 to 1-37 = 62 to 71J Tw.) deposit granular alumina, while 
 the supernatant liquor contains a subaluminate and excess of caustic soda. 
 This aluminate of soda agrees in its properties with the corresponding potassa 
 salt. 
 
 Since bauxite is a very pure native hydrate of alumina, the aluminate of 
 soda prepared with it is used for the production of acetate of alumina in the 
 following manner: — The aluminate of soda is precipitated by the addition of 
 a very slight excess of hydrochloric acid ; the gelatinous alumina thus obtained 
 is thoroughly washed with boiling water, and next dissolved in acetic acid. 
 The percentage composition of the pure aluminate of soda is 47"2i soda and 
 5279 alumina ; the commercial product, as met with in the French market, is 
 contaminated with about 9 per cent of impurities, due to the presence of sul- 
 phate of soda and chloride of sodium in the soda-ash. 
 
 As regards the methods of fixing alumina upon woven fabrics, it must be in 
 a perfect state of solution, while it is also necessary that the hydrate of 
 alumina should be precipitated, in the best possible physical condition, within 
 the fibre of the fabrics. W. Crum found that the microscopic examination of 
 fibres mordanted with acetate of alumina and dyed, and similar fibres mor- 
 danted with chloride of aluminium and dyed, presented differences, inasmuch 
 as in the first instance the coloured lake, or combination of alumina and 
 colouring matter, was chiefly accumulated within the central canal of the 
 fibre ; in the second case, however, the periphery of the fibre only was 
 coloured. 
 
 Alumina can be obtained in solution — (1), in the state of a saline solu- 
 tion of that base; (2), as a basic salt; (3), as a soluble modification of the 
 earth itself; (4), in combination with alkali. Some of the salts of alumina 
 can be brought into contact with the cotton fibre without any decomposition 
 
mm ^m ^P^M2^ 
 
 IBHH 
 
 
 280 
 
 DYEING AND CALICO PRINTING. 
 
 whatsoever ensuing, so that a simple washing in cold water eliminates all the 
 alumina taken up. This happens, e.g., with nitrate and sulphate of alumina 
 and with alum. Whenever it may be desirable to apply such salts for the 
 purpose of mordanting cloth it is necessary to pass the cloth, after it has been 
 impregnated with the aluminous solution, through a bath containing sub- 
 stances capable of precipitating within the fibres either hydrate of alumina or 
 at least an insoluble basic salt of that base. Some of the salts of alumina 
 are decomposed by moist heat (steam), thereby giving up to the fibres of the 
 cloth the whole or a portion of the alumina, or becoming converted into a 
 basic salt. The acid set free is volatilised, or leaves the tissue. The 
 chloride, acetate, and hyposulphite of alumina are salts of this description. 
 These salts become fixed by exposing the saturated tissues to a warm and 
 moist atmosphere. This result is not simply a dissociation of the constituent 
 elements of the salt, but the intervention of the water is absolutely required 
 for the formation of the hydrate of alumina. The action is therefore to be 
 considered as a saponification, in the more extended sense of this word as 
 understood by chemists. 
 
 It is here the proper place to give a few particulars concerning the 
 process just mentioned, and known as " ageing." The mordants generally 
 used for madder styles are the pyrolignites, or acetates of iron and alumina, 
 which under the influence of ageing— which we are about to describe — are so 
 decomposed as to leave on the cloth either an insoluble oxide or a sub-salt, 
 which becomes the intermediate agent for fixing on the fabric the colouring 
 matters of madder. The fixing of mordants by ageing was first practically 
 carried out by Mr. Walter Crum, an eminent and highly scientific calico- 
 printer. On the proper ageing of printed goods, says Dr. Schunck, depends 
 in a great measure the success of many styles. Should a room be too hot or 
 too dry, imperfect fixation of the colour ensues, and meagre and uneven tints 
 are obtained in the subsequent operations. To give some idea of the im- 
 portance of this step in calico-printing, we may here state that " ageing 
 rooms," as they are called, are in several print-works of enormous dimensions, 
 and generally constitute a separate building. Those of Messrs. Edmund 
 Potter and Co. and Messrs. T. Hoyle and Sons, all at or near Manchester, 
 may be particularised as forming quite a feature in their works. The process 
 of ageing in calico-printing is that by which a mordant, after being applied to 
 a cotton fabric, is placed in circumstances favourable to its being completely 
 incorporated with and fixed in the fibre. It has generally been found desirable 
 that calico printed with a mordant should, before dyeing, be exposed to the 
 atmosphere for some time in the ageing room, in single folds, which, generally 
 speaking, requires several days, the object being to liberate the acetic acid 
 from the acetates of iron or subacetates of alumina, and to oxidise the 
 protoxide of iron. It was for many years believed that oxygen was the only 
 necessary agent ; and although some printers had observed that moisture 
 facilitated the process, this fact was not generally known until Mr. J. 
 Thorn, of Manchester, claimed the introduction of moisture as an important 
 agent in the process of ageing, in a patent which he took out in 1849. 
 Mr. Walter Crum was, however, the first printer who applied this principle 
 practically. He describes the process as adopted at Thornliebank (near 
 Glasgow) in the following words : — A building is employed 48 feet long 
 
MORDANTS. 
 
 281 
 
 inside and 40 feet high, with a mid-wall from bottom to top running length- 
 wise, so as to form two apartments, each 11 feet wide : in one of these apart- 
 ments the goods first receive the moisture they require. Besides the ground 
 floor it has two open sparred floors, 26 feet apart, upon each of which is fixed 
 a row of tin rollers, all long enough to contain two pieces of cloth in their 
 breadth. The rollers, being threaded, are set in motion by a small steam- 
 engine ; and the goods to be aged, which are at first placed in the ground 
 floor, are drawn into the chamber above, where they are made to pass over 
 and under each roller, issuing at last at the opposite end, where they are folded 
 into bundles on one of the three stages which are placed there. These stages 
 are partially separated from the rest of the chamber by woollen cloths. 
 While the goods are traversing these rollers they are exposed to heat and 
 moisture, furnished to them by steam, which is made to issue gently from 
 three rows of trumpet-mouth-shaped openings. The temperature is raised 
 from 8o° to ioo" F., or more, a wet bulb thermometer indicating at the same 
 time 76 to 96 F., or always 4 less than the dry bulb thermometer. In this 
 arrangement 50 pieces of 25 yards each are exposed at one time, and, as each 
 piece is a quarter of an hour under the influence of steam, 200 pieces pass 
 through in an hour. Although workpeople need scarcely ever enter the 
 warmest part of this chamber, a ventilator in the roof is opened when there 
 is any considerable evolution of acetic acid. The mordant does not, however, 
 become fully " aged " by this process alone, although it is acted upon as much 
 as if it had hung a whole day in cold air. It has received, however, the 
 requisite quantity of moisture, about 7 per cent of the weight of the piece, 
 and is thus enabled, if the mordant be iron, to take oxygen from the air, and 
 to become changed with time into the sesquiacetate and sesquihydrate of 
 oxide of iron. In order to be sufficiently aged it must be left one or two, or 
 even three, days in an atmosphere still warm and moist. 
 
 It had been ascertained long before, at Thornliebank, that exposure in single 
 folds after moistening was not necessary. The experiments of the late Prof. 
 T. Graham, on the diffusion of gases through small apertures, had served to 
 suggest that, for the absorption of the small quantity of oxygen required, the 
 goods might as well be wrapped up and laid in heaps. Accordingly, in the 
 operation in question, the moistened goods are carried in bundles into the 
 building, on the opposite side of the mid-wall already mentioned, and laid 
 upon the sparred floors, placed at heights corresponding with the stages in the 
 first apartment. Upon these floors 7000 or 8000 pieces may be laid at a time, 
 and, since each piece is 25 yards long, 100 miles can be stored at once. It is 
 necessary, of course, that an elevated temperature and a corresponding degree 
 of moisture be preserved in the storing apartments, day and night, and 8o° F. 
 is sufficient, with the wet bulb thermometer at 76 . To effect this condition a 
 large iron pipe is placed along the ground floor underneath, and moderately 
 heated by steam, while a row of small jets in the same position are made to 
 project steam directly into the air of the room. The whole building is protected 
 from external cold, and consequently from condensation of steam, by a warmed 
 entrance room, and by double windows, thick walls, and a double roof. Small 
 steam-pipes are also placed at other points where they seem to be required, 
 and the apartment which contains the rollers is specially heated, when not in 
 use, by a couple of steam-pipes, which are placed under the ceiling of the 
 ground floor. 
 

 : ESI 
 
 282 
 
 DYEING AND CALICO PRINTING. 
 
 The process of ageing, as thus detailed, was in operation at Thornliebank 
 in the autumn of 1856. About a year afterwards it began to be adopted by 
 other printers, and now it is pretty generally used in the best arranged printing 
 establishments in Scotland and in Lancashire. The basic salts of alumina 
 readily yield to the textile fabric the excess of alumina they contain, and 
 become thereby converted into neutral saturated salts. Heat and moisture, in 
 this case, aid the attraction exerted by the porosity of the fibre. As regards 
 alkaline aluminates they are applied as mordants, — that is to say, the alumina 
 they contain is fixed to the fibre by (1), simple exposure to the open air, when 
 the carbonic acid of the atmosphere saturating the alkali causes the deposition 
 of alumina; (2), the cloth is passed through a very dilute acid solution, too 
 weak to re-dissolve the alumina, sour buttermilk being sometimes used for 
 that purpose in Switzerland and Holland ; (3), by causing the cloth to be passed 
 through an aqueous solution of ammoniacal salt ; alumina does not combine 
 with ammonia, which is of course hereby volatilised ; (4), by immersion in a 
 solution of a metallic salt, the oxide of which forms an insoluble aluminate 
 with alumina. 
 
 The preparation of the red liquors as used for madder work has undergone 
 a great number of variations and improvements since calico-printing and 
 dyeing were first introduced into Europe. Many manufacturers use alum and 
 white or brown acetate of lead as the chief ingredients ; others, again, apply 
 sulphate of alumina, free from iron, like that obtained from bauxite. The 
 alkaline aluminate is not very frequently used. There is much difference of 
 opinion as regards the preparation of the red liquor. According to pure 
 theoretical views the quantity of acetate of lead should be so regulated that 
 all the sulphuric acid of the neutral sulphate of alumina contained in alum is 
 precipitated as sulphate of lead, leaving in the liquor acetate of alumina fully 
 saturated, and, if alum has been used, sulphate of ammonia or of potassa. 
 There is no reason for using excess of acetate of lead so as to convert also 
 the alkaline sulphates into acetates. Since this opinion was defended by 
 M. Sebille, who advised the use of 125 parts of acetate to 100 of alum, M. D. 
 Kcechlin-Schouch has put this matter to practical test, by using the same 
 quantity by weight of alum and of water, with variable quantities of acetate 
 of lead, when the proportions of this latter salt varied as much as from 75 to 
 125 parts for 100 of alum, the quantity of water remaining the same. The 
 dyes obtained did not exhibit any difference at all. Below 75 the shades 
 became weaker, when the quantities of acetate of lead and water were left 
 the same and the quantity of alum varied : it was found that the strongest 
 mordant was formed when 3 parts of acetate to 4 of alum were used. The 
 theory of M. Sebille would require 5 parts of acetate to 3 of alum. It is 
 clear that these observations extend to sulphate of alumina as well, care being 
 taken to alter the ratios ; and we may therefore safely conclude that there is 
 no need whatever to carry the double decomposition on to the point of com- 
 plete exchange, and that a certain quantity of sulphuric acid may be left in 
 the liquid without fear of affecting injuriously the strength of the mordant. 
 What is contained in the mordant prepared with 100 parts of alum and 75 of 
 acetate of lead cannot at present be determined with perfect certainty. In 
 other words, we do not know anything certain about it. All that can be said 
 is, that the two acids present partake of the base in proportion to their bulk. 
 Take the case of a mordant simply prepared with sulphate of alumina : this 
 
MORDANTS. 
 
 283 
 
 will contain, after removal of the sulphate of lead by filtration, a variable 
 quantity of basic sulphate of alumina, according to the greater or less amount 
 of sulphuric acid which has escaped precipitation, and also basic acetate of 
 alumina and free acetic acid, which keeps both these basic salts in solution. 
 When this liquid is printed on cloth it begins speedily to give off volatile 
 acetic acid, and the basic salts are fixed on the tissue, the process being com- 
 pleted by ageing. 
 
 According to the direct experiments made by M. D. Kcechlin, the basic 
 sulphate of alumina has been proved to be an excellent mordant. He pre- 
 pared this salt by partial precipitation of a hot and concentrated aqueous 
 solution of alum, by means of caustic potassa. The salt obtained was dis- 
 solved in a sufficient quantity of acetic acid, and the liquid was used for 
 printing, and the tissue exposed to ageing. It is quite clear that nothing but 
 subsulphate (basic sulphate) of alumina could remain on the cloth after 
 drying, since the elimination of the acetic acid must have been complete, and 
 the sulphuric acid could not, under any conditions, leave the base or the cloth. 
 This cloth, after having been dunged, was put in the dye-beck, and gave 
 excellent results. This experiment proves that we may admit, at least, that 
 as regards the ordinary mordants there remains on the cloth, after printing and 
 ageing, a certain quantity of subsulphate of alumina, which contains all the 
 sulphuric acid of the neutral sulphate of alumina which has not been combined 
 to sulphate of lead plus a certain dose of alumina or subacetate of alumina 
 derived from the acetate of that base decomposed during the ageing process. 
 When exactly 100 parts of alum and 75 of acetate of lead are employed, about 
 two-thirds of the sulphuric acid of the sulphate of alumina are displaced : the 
 composition of the liquid which is the result of this reaction is represented by 
 a liquid prepared by dissolving 1 molecule of basic sulphate of alumina in 
 2 molecules of acetic acid. Whether or no the two acids do temporarily each 
 partake of a portion of the base present, after the ageing process there will 
 only be basic sulphate of alumina left on the cloth. These considerations, 
 which somewhat elucidate the true nature of the mordants, do not clash at all 
 with the use of pure acetate of alumina. What is said is only meant to prove 
 that the subsulphate of alumina, and the sulphates of soda, potassa, and 
 ammonia, or also the alkaline acetates, can be mixed along with the acetate of 
 alumina without injuring its excellent properties as a mordant. We may 
 also state here that, as regards the materials to be used, the purest articles 
 answer the purpose best in every respect. 
 
 The following prescriptions for red liquors are given by M. D. Kcechlin : — 
 
 Strong Mordant, No. 1. 
 30 gals, of water, 6 of which are a decoction of Lima-wood to " sighten " 
 the work ; 165 lbs. of alum ; i6J of soda-crystals ; and 165 lbs. sugar of lead. 
 
 Mordant, No. 2. 
 Water as above ; 82 £ lbs. of alum ; 8i lbs. of soda-crystals-; 55 lbs. acetate 
 of lead. 
 
 These formulae are old. The following are of more recent date : — 
 
 Strong Mordant. 
 11 kilos, alum ; 82*5 grms. acetate of lead ; 32 litres boilin 
 
 g water. 
 

 MW1MWBBE8BJ 
 
 2 8 4 DYEING AND CALICO PRINTING. 
 
 5/4 Mordant. 
 625 grms. alum ; 450 grms. acetate of lead ; 2 litres boiling water. 
 
 The following mixtures are in great repute with some dyers : — 
 
 A. B. C. 
 
 Alum 16 kilos. 8 - o kilos. 10 kilos. 
 
 Acetate of lead .. .. 12 „ 8-5 ,, 10 „ 
 
 Boiling water 62 „ 6o-o „ 20 ,, 
 
 Extract of Lima-wood, at 
 
 20 Baume 2 ,, 4-0 ,, (at 3 ) 
 
 30 Tw. 4 Tw. 
 
 In England it is customary to make up the mordants without the peach- 
 wood liquor ; and only add it when the colour is being prepared for printing. 
 
 Red Mordant (Liquor) for Garancin, 
 At n° B. = 1-083 S P- g r - = I 5° ™ w. 
 25 kilos, alum ; 19 kilos, of acetate of lead ; 80 litres of water. 
 
 Strong Mordant, 
 At n° B. 
 2-5 kilos, alum ; 2 kilos, acetate of lead ; 6-3 litres of water. 
 
 Mordant for Red with Garancin. 
 Alum, 1608 kilos. ; acetate of lead, 12-08 ; water, 40-16 litres. 
 
 According to the experiments of M. D. Kcechlin, the mordant No. 2 (just 
 mentioned) is strong enough to furnish, with nearly all tinctorial substances, 
 the strongest tints which they can produce consistent with complete saturation. 
 Instead of keeping one standard mordant, which, by being diluted with water, 
 might serve to produce the different shades desired, the manufacturers prefer 
 to prepare a series of mordants graduated in strength according to the style 
 of work intended. The reason for this system is, that a strong mordant does 
 not keep so well for any length of time ; moreover, since all these kinds of 
 mordants, even when kept in well-stoppered vessels, deposit in time more or 
 less acetate of alumina, which is not readily again taken up in acetic acid, it 
 is convenient not to prepare too much of any of these mordants at once. 
 
 Pure acetate of alumina in solution can be heated to the boiling-point 
 without decomposition, or without throwing down any basic salt, but the 
 mordants containing sulphate of potassa or basic alum become turbid on 
 heating, and yield an abundant precipitate, which re-dissolves on cooling. 
 According to Gay-Lussac this precipitate is hydrate of alumina; but since 
 M. D. Kcechlin found it to consist of 100 parts of sulphuric acid and 343-5 of 
 alumina, it should be considered as a mixture of alumina and a basic sulphate 
 of alumina. It is an interesting fact that the formation of this precipitate 
 takes place at a lower temperature, and more abundantly in the weaker mor- 
 dants than in the stronger. The solution of subsulphate of alumina in acetic 
 acid, obtained by partially precipitating at boiling heat a concentrated solution 
 of alum with caustic potassa or soda, yields a good mordant. 
 
 If it is needful to prepare a solution of acetate of alumina with sulphate of 
 alumina, the process is first to make a solution of the sulphate at from 31 to 
 
MORDANTS. 
 
 285 
 
 33 Baume = sp. gr. 1*275 to 1*298 = about 50 to 55 Tw. From no to 115 
 parts of this solution are precipitated by 100 parts of acetate of lead previously 
 dissolved in 30 parts of water: the resulting liquor has, after filtration, a 
 strength of from i*n6 to 1*125 sp. gr. = about 21 to 23J Tw., and contains 
 from 18 to 19 per cent of acetate of alumina. This is the highest strength 
 attainable; and the liquor yields, when employed as a mordant, the same 
 result as that obtained from alum, provided the sulphate be quite free from 
 iron. It has already been observed that, instead of acetate of lead, acetate of 
 lime is frequently used in this process : 100 parts of alum, 100 of water, and 
 150 of crude acetate of lime solution, sp. gr. 1*087 — about 15$° Tw., yield 
 a red liquor having a strength of sp. gr. 1-095 = about 18 Tw. Excess of 
 lime must be avoided, since it renders the colours dull. 
 
 M. E. Kopp has called attention to the use of hyposulphite of alumina as a 
 mordant. This salt is perfectly soluble in water, and the solution is decom- 
 posed at a boiling heat into sulphurous acid, sulphur, and alumina. None of 
 these compounds can affect the strength or quality of the fibre to which it is 
 applied. Pure hyposulphite of alumina may be prepared by the double 
 decomposition of crystallised sulphate of alumina and crystallised hyposulphite 
 of lime. Of the first-named salt take 4*167 kilos., and after solution in 
 water there is added a solution of 4*875 kilos, of the latter salt. The preci- 
 pitate of sulphate of lime is removed by filtration through stout flannel, and 
 the precipitate strongly pressed : there is thus obtained a perfectly clear 
 solution, which can be preserved for a long time, even in contact with air. A 
 solution of hyposulphite of alumina of 120 sp. gr. contains as much alumina 
 as a solution of acetate of no sp. gr. The solution of hyposulphite is 
 readily thickened in the cold by means of gum, torrified starch, or British gum. 
 The hyposulphite solution resembles the acetate solution in this respect, also, 
 that it is better for being not quite pure and more advantageously used when 
 mixed with a certain proportion of alkaline salts : 6 kilos, of alum are com- 
 pletely decomposed bythe use of 4*65 kilos, ofhyposulphite of soda, or 4-85 kilos, 
 of crystallised hyposulphite of lime, so that 2 kilos, of this last salt can replace 
 3 kilos, of acetate of lead, which latter is obviously a far more expensive salt. 
 
 Since there is some difficulty in thickening sulphates with starch, M. Kopp 
 advises to prepare first hydrochlorate of alumina, which, in the state of a 
 thickish syrup, is incorporated with cold starch paste. To this mixture is next 
 added hyposulphite of soda, in such proportion as to decompose two-thirds 
 or three-fourths of the hydrochlorate of alumina. In order to prepare a hydro- 
 chlorate of alumina suitable for this purpose, it is proper to decompose 6 kilos, 
 of ammonia-alum in aqueous solution, by means of 2*78 kilos, of dry chloride 
 of calcium (not chloride of lime). The liquid, after being drawn off from the 
 precipitated sulphate of lime, is evaporated to the consistency of a syrup in a 
 leaden vessel. On cooling, there are formed crystals of sal-ammoniac ; the 
 mother-liquor is drawn off, and evaporated at 150 until a pellicle forms 
 on the top of the liquid, which, on cooling, becomes a solid, white, deli- 
 quescent mass. M. Kopp prepares hyposulphite of lime by the action of 
 sulphurous acid gas upon a previously boiled mixture of basic oxysulphide of 
 lime (soda waste), with 10 per cent of its weight of pulverised sulphur and 
 water. As soon as the liquid shows an acid reaction it is neutralised and allowed 
 to stand till clear, and evaporated at a gentle heat. In this way beautiful 
 
wyMMy 
 
 BTOBBBG HQhBOBBB UKb 
 
 286 
 
 DYEING AND CALICO PRINTING. 
 
 crystals are obtained. When this salt is precipitated, in aqueous solution, by 
 sulphate of soda, hyposulphite of soda is formed, which crystallises readily. 
 The hyposulphite has the following advantage as a mordant over the acetate 
 of alumina : — (1), it is more economical, especially when mordants are required 
 which are either not thickened at all or but slightly ; it yields, when equal in 
 strength to the acetate, more full-bodied colours ; (2), it is more rapidly and 
 completely fixed than any other alumina mordant ; (3), it prevents, to a cer- 
 tain extent, the fixation of iron, because, as long as there remains hyposulphite 
 of alumina undecomposed in the fibres, any iron which may be contained in 
 the preparation (mordant) is kept in the state of protoxide, and cannot adhere 
 permanently to the fibre. Only after the complete decomposition of the hypo- 
 sulphite can oxidation of any iron compound present set in, and its fixation 
 take place. Notwithstanding these advantages, against which has to be set 
 the slight inconvenience of the evolution of sulphurous acid in the ageing 
 rooms, the hyposulphite is hardly, if ever, now used. The general opinion 
 of English printers is, that the hyposulphite does not present any marked 
 advantage over the common red liquors. 
 
 We now come to another point, viz., the methods of thickening these mor- 
 dants without injuring their properties. We have already stated that one and 
 the same mordant, thickened to the same degree with different thickeners, 
 does not, on dyeing, yield results of the same value. Gum Senegal especially 
 and also some of the gums known as Arabic gums do not aft well for the 
 fixation of an aluminous sub-salt. Moreover, two mordants of the same 
 strength, but thickened with different substances, give shades which vary in 
 beauty and intensity. It is, for instance, well known that a mordant thickened 
 with starch paste combines more readily with the cloth, and yields deeper 
 shades than the same mordant thickened with gum ; but for certain kinds of 
 colour gum is preferable, since it gives more transparency to the colours, 
 while a portion, however small, of the starch-paste remains always with the 
 mordant, notwithstanding the clearing process. The difference in the inten- 
 sity ■of a colour may arise from the increase of bulk caused by some thickeners 
 which have to be used in larger quantity, in order to obtain an equal con- 
 sistence, and this causes, as it were, a greater or less distance between the 
 particles of alumina. Any mordant strongly thickened with gum dries too 
 rapidly, and combines only slightly with the fibre, thereby causing a weakness 
 of the colours. The consistence of a mordant can be readily increased, by 
 means of starch or farina, without any such undesirable results ensuing. A 
 strong and simultaneously acid mordant is not readily thickened by means of 
 starch, and the liquid does not then acquire a sufficient consistency, and it is 
 therefore far better to thicken it with gum or torrified starch. A mordant 
 which contains an excess of alum (2 parts of alum for one part of acetate of 
 lead), if thickened with starch, attracts water even after the lapse of a single 
 day. Hence it may be readily seen that the degree of consistence and the 
 nature of the thickening substance must vary, and are accordingly regulated 
 by the kind of printing to be done, the specific gravity, and the quantity of 
 the acetate contained in the mordant. The thickeners usually applied for red 
 and pink colours are white starch and roasted starch. When starch is used 
 it is necessary to boil the liquid, which causes the precipitation of a sub-salt 
 of alumina, which, however, remains suspended by the viscosity of the liquid, 
 
MORDANTS. 
 
 287 
 
 and becomes re-dissolved on cooling, especially if well stirred until quite cold. 
 It should not be used hot. When it is required to dilute the mordant with 
 much water, as for instance for light rose-colours, it is best to thicken the 
 water first by means of starch, and to add next the mordant to that mixture 
 when nearly cold. The following are prescriptions of thickened mordants for 
 red and rose-colours, ready made up for printing with the cylinder-machine.* 
 
 Deep Red. Medium Red. Bright Red. 
 Acetate of alumina at 9 Baume) f ^ ][ Htre % mn 
 
 = 1*067 sp. gr. = 13 Tw. . . J 
 
 Water 1 „ 4 litres 15 litres 
 
 Starch 240 grms. o o 
 
 Roasted starch 60 „ 2 kilos. 6 kilos. 
 
 Gallipoli oil (huile toumantc) . . 30 ,, 
 Decoftion of Lima-wood . . . . 164 „ 
 
 Red Mordant for Madder. 
 
 Garancin mordant at 11° Baume 1 litre 
 
 White starch no grms. 
 
 White-coloured roasted starch (British gum) 75 ,, 
 
 Bright Red. 
 
 Strong mordant at 11° Baume (see above) 1 litre 
 
 Acetic acidf at 2° B. = 1*007 S P* g r * = J i° Tw 4 litres 
 
 Solution of British gum containing 750 grms. to the litre 9 ,, 
 
 Pipe-clay water containing 1 kilo, of pipe-clay to the litre 5 ,, 
 
 Red Mordant for Deep Red. 
 (For fine designs). 
 
 Acetate of alumina at 9° B i*o litre 
 
 Water 60 litres 
 
 Brazil-wood decoction io*o „ 
 
 Acetic acid (as above) 5-0 „ 
 
 Alum 2*5 kilos. 
 
 Pyrolignite of lead (crude acetate) 2*5 ,, 
 
 White starch 3*0 „ 
 
 Gallipoli oil (huile toumante) 375 grms. 
 
 Solution of nitrate of copper at 52 B. = 1*547 sp. gr. | 
 = 109J Tw 1 
 
 Note that the sulphate of lead which is formed remains in the mixture, 
 serving the purpose of giving body, and thereby aiding the regularity of the 
 execution of the fine designs. 
 
 * See D. Kcechlin-Schouch, Sur le Mordant Rouge, " Bulletin de la Societe Industrielle de 
 Mulhouse," vol. i., p. 277. 
 
 t It should be borne in mind that the specific gravity of vinegar and of acetic acid is no 
 proper test for their goodness ; acetic acid is specifically lighter than water ; vinegar, according 
 to its origin, contains a variety of other substances in solution along with acetic acid and water. 
 The quantity of acetic present in vinegar varies from 2 to 8 per cent. 
 

 288 
 
 DYEING AND CALICO PRINTING. 
 
 Red Liquor, or Mordant. 
 
 White starch 2 kilos. 
 
 British gum .. 4 ,, 
 
 Strong mordant (see p. 284) . , 10 litres 
 
 Lima-wood extract at 3 1° T\v J litre 
 
 Gallipoli oil (huile toumante) J ,, 
 
 Pyroligneous acid (crude acetic) 5 litres 
 
 Hydrochloric acid \ litre 
 
 Pyrolignite of lime 1 kilo. 
 
 Add when cold — 
 
 Tin-salt 750 grms. 
 
 Other Red Mordant (Red 4). 
 
 Mordant A (see p. 284) 20 litres 
 
 White starch 6 kilos. 
 
 Gallipoli oil 250 grms. 
 
 Turpentine (oil of) 250 ,, 
 
 Red 4/2. 
 
 Mordant A (see p. 284) 24 litres 
 
 Water 6 ,, 
 
 White starch 6 ,, 
 
 Gallipoli oil 250 grms. 
 
 Turpentine (oil of) 250 „ 
 
 Mordants for Rose-Colour (Pink). 
 
 Boiling water 30.J litres 38 litres 
 
 Acetic acid at n \° Tw i£ ,, 2 ,, 
 
 Mordant 5/4 (see p. 284) : 625 grms.\ 
 
 alum, 450 grms. acetate of lead, V 8 ,, 2j „ 
 
 2 litres boiling water / 
 
 Dark roasted starch 20 kilos. 20 kilos. 
 
 Gallipoli oil 375 grms. 375 grms. 
 
 Turpentine (oil of) 375 „ 375 „ 
 
 In all these cases the acetic or pyroligneous acid must be well mixed with 
 the mordant before adding it to the water, starch, &c. This is especially 
 important for light shades. 
 
 It is quite clear that these prescriptions are varied in different ways, and 
 differ not only in different countries, but also according to the experience and 
 taste of the manufacturers : those above quoted are all French. The following 
 are English, but are stated to have been prepared in accordance with principles 
 laid down in M. D. Kcechlin's paper on red liquor already alluded to : — 
 
 No. 1. No. 2. No. 3. No. 4. No. 5. No. 6. 
 
 Water, gallons 45 45 45 45 45 45 
 
 Alum, lbs 100 100 200 igo 190 129 
 
 Acetate of lead, lbs. 100 i2g 200 190 129 100 
 
 Crystals of soda 10 10 10 19 o o 
 
MADDER. 289 
 
 The alum, previously ground, is dissolved in the water heated to 140 F. ; the 
 crystals of soda are next dissolved with stirring, and then the acetate of lead 
 added in coarse powder, and the whole well stirred for a considerable time, 
 and afterwards at intervals during two or three days. Nos. 1 and 2 are com- 
 mon reds for calico, No. 2 being better adapted for a gum colour and for 
 blocking than No. 1 ; Nos. 3 and 4 strong mordants, suitable for muslin or 
 light goods; Nos. 5 and 6 will do for garancin, and are suitable for mixing 
 with crystals or muriate of tin for forming a resist. 
 
 Red Liquors from Acetate of Lime. 
 
 No. 7. No. 8. 
 Acetate of lime liquor at 24 Tw., gallons .... 50 go 
 
 Alum, lbs 200 — 
 
 Sulphate of alumina, lbs — 272 
 
 Ground chalk, lbs 12 34 
 
 On account of the cheapness of acetate of lime it is more used than acetate 
 of lead. The above two red liquors are put together by first heating the 
 acetate of lime liquor, in a copper boiler, to a temperature of 140 F. ; then 
 adding the alum or sulphate of alumina, and stirring until the lumps have 
 disappeared ; and lastly, the chalk is added by small portions at a time, to 
 avoid loss by effervescence. The whole is then well stirred until nearly cold, 
 allowed to settle, the clear drawn off, and the bottoms drained upon a woollen 
 filter and washed with water until the washings fall as low as 2° Tw., when 
 they are not worth washing any more. The red liquor No. 7, used at 20 Tw., 
 gives the darkest red obtainable on calico for madder and garancin ; the No. 8 
 liquor, at 16 Tw., is used for resist reds, and for mixing with iron liquor (iron 
 mordants, about which more below) to produce chocolates for garancin work, 
 and also is reduced for light reds. These two liquors are quite sufficient for 
 the ordinary run of madder and garancin work. 
 
 Red Liquors for Madder Pink (Rose-colour). 
 
 No. 9. No 10. No. 11. No. 12. No. 13. 
 
 Water, gallons 4I 1 20 3 60 
 
 Alum, lbs 16 3 J 75 13 125 
 
 Acetate of lead, lbs 12 2J ioi — 100 
 
 Acetate of lime (dry), lbs. .. — 30 — 
 
 Ground chalk, lbs — — 5 — — 
 
 Common salt, lbs — — 10 — — 
 
 Nitrateofzincsolutionat i5°Tw. — — — 1 — 
 
 No. 9 is for dark and No. 10 for light pink, being reduced or diluted when used 
 with 3 parts of water to 1 part of liquor; No. 11 is excellent, for the reason 
 that the addition of common salt has the effect of causing the mordant to 
 attract moisture, and thus improve the ageing. The nitrate of zinc in No. 12 
 has a still stronger attraction for water, but should be added after thickening 
 and when the liquor is cold, since this salt otherwise causes the starch and 
 flour to run thin if boiled with them. No. 13 is only for reducing for light 
 pinks (rose-colour), and will not give a good dark pink. 
 
 We now direct our attention to the mordants used to produce, with madder 
 and its preparations, blacks, purples, and lilacs. The basis for these is hydrated 
 
 u 
 
■■ BaBI BBBBBBBBBBBBBBa| 
 
 ' BBS Baa 
 
 2go 
 
 DYEING AND CALICO PRINTING. 
 
 peroxide of iron, or a basic insoluble salt of iron. We have already observed 
 that the substance just named is used as a colour by itself, for producing 
 nankin, rust, and chamois colours; but the quantity of hydrated oxide of iron 
 required to yield with madder pigments the utmost effect is too small to pro- 
 duce by itself any colour upon the fabric. 
 
 The means employee! to fix peroxide of iron upon tissues are — (i), the use 
 of basic salts of peroxide of iron, which give up a portion of the oxide as a 
 consequence of the capillary attraction of the fibre ; (2), the use of certain 
 neutral salts of peroxide of iron, the oxide of which can be precipitated by the 
 employment of ammonia, caustic or carbonated alkalies, and some alkaline 
 salts (e.g., phosphates, arseniates) the acid of which forms, with the peroxide 
 of iron, insoluble compounds; (3), those salts of the peroxide of iron which 
 are spontaneously decomposed by the volatility of the acid, while the base is 
 set free ; (4), the use of protoxide salts of iron, which, however, require higher 
 oxidation simultaneously with or after the transferring of the oxide to the 
 fibre ; (5), lastly, the alkaline solutions of peroxide of iron. While enume- 
 rating all these possible means, we should also state that only one among 
 them has been and is actually used, and after a lengthened experience has 
 been found the best, viz., the proto-acetate of iron, or, as it is technically 
 called, pyrolignite of iron. These preparations, after having been printed on, 
 and after ageing, become changed, lose a portion or the whole of their acetic 
 acid, and take up oxygen, with the result that there is deposited on the cloth 
 an insoluble hydrated peroxide of iron, or at least an insoluble subacetate of 
 peroxide of iron. It must be here remembered that, according to some 
 authorities, the intermediate or magnetic oxide of iron is actually formed on 
 the cloth, and is more efficient as a mordant than the peroxide. The tarry 
 and other organic matters in ordinary iron-liquor have a decided effect in re- 
 tarding the peroxidation of the protoxide present. 
 
 M. H. Schlumberger finds that good results may be obtained by the appli- 
 cation of aceto-ferruginous solutions obtained by — (1), double decomposition 
 between acetate of lead and sulphate of iron (green vitriol, copperas) ; (2), by 
 acetic acid and iron (viz., the slow solution of scrap iron in crude acetic 
 acid); (3), solution of iron in Bourgogne vinegar; (4), solution of iron in 
 purified pyroligneous acid ; (5), solution of iron in purified pyroligneous acid, 
 and boiling for five minutes ; (6), solution of iron in crude pyroligneous acid ; 
 (7), by double decomposition between protosulphate of iron and pyrolignite of 
 lime. Before being applied to cloth as a mordant, these solutions ought to 
 contain the iron in the state of protoxide : it is clear that the peroxidation of 
 these liquids has to be guarded against as much as possible, because if it takes 
 place the mordants no longer combine with the fabric, and that which may 
 adhere is very readily removed by the subsequent cleansing and dunging. 
 The effects of oxidation are especially injurious with blockwork, where fre- 
 quently a small portion of mordant remains exposed over a large extent of 
 surface to the action of the air. This change is far less perceptible in 
 machine work. The nature of the thickening substance exerts a very great 
 influence upon the fixation of oxide of iron. All things considered, starch 
 fixes more of the oxide of iron than British gum, and the latter more than gum 
 Senegal. The degree of viscosity of the mordant also greatly influences the 
 result, and it is hence necessary to give to every mordant that proper degree 
 of thickness which is required by the character of the design. The purified 
 
MADDER. 291 
 
 pyrolignite of iron is prepared with pyroligneous acid deprived by distillation 
 of the greater part of the tarry matters, and is of a strength of io° Baume, 
 = sp. gr. 1-075. 
 The following mordants are for purples thickened with British gum : — 
 
 Purple 8. Purple 32. 
 
 Boiling water 48 litres 48 litres 
 
 Pyrolignite of iron at io° Baume .. 6 ,, 1$ „ 
 
 British gum 36 kilos. 30 kilos. 
 
 Oil of turpentine 375 grms. 375 grms. 
 
 Purple 10. — -2 parts of purple 32 and 22 parts of purple 8. 
 Purple 12.- — 4 parts of purple 32 and 20 parts of purple 8. 
 Purple 16. — 8 parts of purple 32 and 16 parts of purple 8. 
 For Black : — 
 
 Pyrolignite of iron at io° Baume 32 litres 
 
 Calcined starch 10 kilos. 
 
 Water 24 litres 
 
 Quercitron liquor at 18 Baume (sp. gr. 1-143) .. .. 2 „ 
 Logwood decoction at 17 Baume (sp. gr. 1-134) . . 2 „ 
 
 Olive oil } litre. 
 
 In former times it was the custom to add to the black mordant destined for 
 block printing a salt of copper, chiefly the acetate, probably for aiding the 
 ready combination of the oxide of iron with the cloth. Since M. Schlum- 
 berger observed that arsenite of copper and lime (15 grms. of each for 1 litre 
 of mordant) has the effect of very particularly favouring the combination of 
 oxide of iron with the cloth, it became the custom to add to mordants for 
 purple a preparation known as the copper solution for purples, prepared with — 
 
 Lime water 48 litres 
 
 White arsenic (arsenious acid) 750 grms. 
 
 Sulphate of copper 750 ,, 
 
 The whole is boiled, and allowed to settle before being used. The use of this 
 copper solution for purple mordant has been dispensed with, because its utility 
 was not quite proved. The action of salts of copper in these mordants is 
 chiefly beneficial with pure solutions of per-salts of iron, and especially when the 
 mordants are thickened with gum Senegal. When other thickeners are used, 
 and other solutions of iron, the pyrolignite for instance, there is no perceptible 
 advantage in the use of a copper solution. 
 
 The mordant for purples known in this country as iron liquor, or black 
 liquor, is made by steeping old iron of all sorts — such as hoops, worn out tin- 
 plate, &c. — in warmed wood vinegar, or pyroligneous acid, obtained by the 
 destructive distillation of wood. By continually moving the acid, and keeping 
 up a moderate heat, it becomes saturated with iron in a few days, crude acetate 
 of iron being formed. The iron liquor is met with in commerce as a fluid 
 black by reflected light, but in thinner layers it is seen to possess a greenish-olive 
 colour. Its taste is inky, and since the crude acid used in its preparation is 
 not quite free from tarry matters the liquor has a peculiar smell. Its strength 
 is from 18 to 28° Tw. (sp. gr. respectively 1-090 and 1-140). 
 
 Iron liquor at about 6° Tw. (sp. gr. 1-030) gives with madder, properly 
 thickened (upon which much depends for the success of first-class styles of 
 work), black ; from 4 (sp. gr. 1-020) downwards to a very diluted state it gives 
 
 u 2 
 

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 HE^HHB 
 
 
 ■ 1HH 
 
 292 DYEING AND CALICO PRINTING. 
 
 various shades of purple or lilac ; mixed with red liquor it gives chocolates, 
 of which more below. 
 
 Hyposulphite of iron can be used, according to M. Kopp's experiments, as 
 a mordant for tissues, but the low price of the acetate will prevent the use of 
 the first-named salt from becoming general. Hyposulphite of protoxide of 
 iron, when exposed to the air, is slowly converted into protosulphate of iron, 
 and lastly, into subsulphate of peroxide of iron, which is insoluble. Since 
 this process of oxidation is very slow, the fixation of the peroxide, or sub-salt, 
 upon the fibre is very intimate, and at the same time no perceptible weakening 
 of the tissues takes place. The hyposulphite is prepared either by the action 
 of sulphurous acid on the protosulphuret of iron suspended in water, or by 
 the decomposition of the same sulphate by means of hyposulphite of lime, or 
 by simply mixing hyposulphite of soda in crystals with a solution of sulphate 
 of iron. 
 
 M. Persoz has proposed the use of an ammoniacal solution of pyrophosphate 
 of iron. If this is printed on to the cloth, and slowly dried, it yields in the 
 dye-beck, with madder, the most beautiful and pure purples and lilacs. Cloth 
 mordanted with this solution can even be dyed in madder becks of madder 
 already exhausted as far as other iron mordants are concerned. 
 
 Mordants for Browns and Chocolates. 
 These mordants are mixtures of those used for reds and for purples, and by 
 simply varying the proportions of these two liquors very many modifications 
 of tints may be produced. For simplicity's sake we call the undermentioned 
 preparation for red (red liquor) Z in the after-mentioned compounds : — 
 
 Z. — Alum 10 kilos. 
 
 Acetate of lead 10 ,, 
 
 Water 20 litres. 
 
 We designate as red mordant for brown the following mixture : — 
 
 Alum 144 kilos. 
 
 Pyrolignite of lead 144 „ 
 
 Water '. 660 ,, 
 
 Crystals of soda (carbonate of) ... . 4 ,, 
 With these the following brown mordants may be prepared : — 
 
 A. — Mordant Z 8 litres 
 
 Pyrolignite of iron at io° Baume (sp. gr. 1*075) . . 4 ,, 
 Extract of quercitron at 20 Baume (sp. gr. 1-162) i litre 
 
 White starch 2-5 kilos. 
 
 British gum 250 grms. 
 
 Gallipoli oil (huile toumante) 90 „ 
 
 B. — Mordant for brown 12 litres 16 litres 
 
 Pyrolignite of iron at io° Baume" . . 2 ,, 4 ,, 
 
 Extract of quercitron at 20 Baume \ . j itre ^ litre 
 
 (sp. gr. 1*162) 1 
 
 White starch 3 kilos. 4 kilos. 
 
 British gum 375 grms. 500 grms. 
 
 Gallipoli oil (huile toumante) .. .. 125 „ 125 ,, 
 
 We cannot in this chapter enter into the mechanical details of printing on the 
 mordants ; it may suffice to say here that it is done chiefly by means of rollers 
 
Plate V 
 
 Block-printing. 
 
 The child to the right hand of the printer is the " tearer," whose business is to keep the colour 
 equally spread out over the surface of the colour-box. 
 
 See page 472. 
 
 .:,— ' 
 
 Painting in Reserves by Hand. 
 
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 JWftiWW iwwIlli fti l ^^ WWPPWMMB 
 
MORDANTS. 
 
 293 
 
 made of copper, and upon which the design is engraved: as regards chintz and 
 large patterns, these are obtained by what is termed block printing, wooden 
 blocks being used containing the engravings of the patterns. Immediately 
 after the cloth leaves the printing-machine it is dried by passing over 
 metal plates heated by steam. By this operation acetic acid is volatilised, 
 and a basic salt remains on the cloth. When block-printing has been 
 resorted to, the drying takes place in a drying-room at a lower temperature 
 than that just given, and consequently less acetic acid is volatilised. 
 The fixation of the mordant is effected by two distinct operations, one of 
 which, viz., the " ageing," has been described already. We add here the 
 following particulars as regards the time required for the mordanted cloth to 
 remain in the ageing room: for chocolates and browns, 72 hours; for purples 
 and browns (another shade), 60 hours ; for blacks and reds (if together). 
 48 hours ; for pinks and reds, when not occurring along with other mordants, 
 from 6 to 20 hours. It should be observed here, also, that proper ventilation 
 must be kept up in the ageing rooms, since the presence of the vapours of 
 acetic acid is injurious to the mordants, and since the admission of cold air to 
 these rooms would condense the steam, and thereby spoil the goods : heated 
 air is required for keeping up the ventilation. 
 
 We may quote here in full the researches made by M. H. Schiffert with the 
 view of ascertaining the nature of the aluminous compound remaining on the 
 tissues after drying and ageing: — (i\ A piece of cotton, printed for foulards (a 
 kind of handkerchief used in France for head-covers by women), and mor- 
 danted with acetate of alumina not containing any sulphate, was dried and 
 submitted to the ageing process for several days ; the cloth was next placed in 
 a glass retort, and, after water and sulphuric acid had been added, distillation 
 was performed. The result of this operation was that a perfectly neutral 
 liquid was obtained, not containing even the slightest trace of acetic acid, 
 which latter would have appeared if a basic acetate had remained on the cloth 
 instead of hydrated alumina. (2). A piece of calico mordanted with alum, 
 three-fourths of the sulphuric acid of which had been replaced by acetic acid 
 from acetate of lead, was similarly dried and aged, and on being treated with 
 cold water yielded sulphate of alumina. It hence follows that the acetate of 
 lead had divided its action between the sulphates of alumina and potassa, 
 both of which were present in the alum, while a portion of the alum had been 
 left unacted upon. The tissue yielded, after being previously washed with 
 water, on distillation with dilute sulphuric acid, not a trace of acetic acid. 
 After washing, and next boiling with carbonate of soda, the resulting liquid 
 did not contain sulphuric acid, which should have been present had there 
 remained a subsulphate of alumina. Treated with hydrochloric acid, 
 aided by heat, a large amount of alumina was obtained, precipitable by 
 ammonia. (3). A piece of calico mordanted for ordinary red, dried, and aged 
 for the usual length of time, did not on assay yield any acetic acid ; treated 
 with cold water it yielded a solution which became turbid by ebullition, 
 throwing down a basic sulphate of alumina which can again serve as a mor- 
 dant by being heated to 70 C. When a piece of this tissue was well and 
 thoroughly washed with cold water it only retained hydrate of alumina, all 
 the sulphuric acid being removed. The result of these experiments is, therefore, 
 that fabrics mordanted with acetate of alumina do not retain, after drying 
 and ageing, any acetic acid at all, not even in the state of basic acetate. 
 

 294 
 
 DYEING AND CALICO PRINTING. 
 
 As regards the ordinary red mordant (red liquor), as generally made up, it 
 appears that there remains a mixture of hydrate of alumina and neutral sul- 
 phate of that base. By treating the cloth upon which these substances are 
 deposited with water, the neutral sulphate of alumina is dissolved, and while 
 in solution reads upon the hydrate of alumina, dissolves a portion thereof, 
 and basic alum is again formed. The iron mordant is oxidised by the loss of 
 acetic acid, and there remains a basic acetate of peroxide of iron. 
 
 The second portion of the process of fixing the mordants comprises the 
 operations of clearing and dunging {degommage, taking away the thickeners ; 
 bousage, from bouse de vache, treating with cow's dung). If the alumina and 
 peroxide of iron were perfectly fixed on leaving the ageing-room, so that these 
 substances were present in the fibre in an insoluble state, the only operation 
 the goods would have to undergo previous to dyeing would be a washing in 
 tepid water, in order thereby to remove the thickeners and other soluble sub- 
 stances which have served their purpose during the printing and are now of 
 no further utility, and a thorough rinsing in fresh cold water. Experience 
 has, however, taught that this simple operation is not sufficient, and does 
 not yield in pradice good results. We will illustrate this point by taking as 
 example the ordinary red mordant, in the preparation of which only half of 
 the sulphuric acid of the alum has been precipitated by acetate of lead. 
 
 M. Schiffert's experiments proving that the goods ready for the cleansing 
 process contain alum and hydrate of aiumina, what will happen when the 
 pieces are washed in water ? The alum will of course dissolve, and corrode, 
 so to speak, a portion of the hydrate of alumina already fixed. This cor- 
 rosion will be, it is quite clear, irregular, — that is to say, at one spot more, 
 and at another less, of the hydrate of alumina will be eaten away, and, as a 
 consequence, the depth and uniformity of the colours will suffer. The white 
 portions of the pattern will, moreover, when brought into contad with a 
 basic solution of alum, take up more or less of the basic sulphate of alumina, 
 and will consequently attrad colouring matters in the dye-beck. Something 
 analogous will of course take place with regard to the iron mordants ; though 
 as yet incompletely fixed, subacetate of peroxide of iron will — on being 
 brought into contad with water — become resolved into soluble neutral acetate 
 and sesquioxide of iron, and the acetate rendered soluble will of course ad as 
 mordant upon the white portions of the pattern. All these effeds are increased 
 by the incomplete decomposition which the mordants undergo in some por- 
 tions of the goods. Indeed, if the heat and moisture are not very regularly 
 diffused over the whole ageing-room, it is possible that in some portions of the 
 goods the mordants are not thoroughly aged, and have consequently retained 
 a great deal of their solubility. Taking all this into consideration, it is quite 
 clear that a simple washing, to dissolve thereby the thickeners, would lead to 
 the produdion of spotted and irregular shades and to the staining of the 
 white portions of the pattern. The manufadurers, dyers, and calico-printers 
 have overcome these difficulties of the cleansing by substituting for water a 
 tepid bath of cow-dung. Cow-dung contains mineral salts and insoluble 
 organic matter, and by the joint adion of these substances it causes the com- 
 plete saturation of the mordant, the precipitation of the metallic oxides, and 
 prevents the adhesion of any oxide which may become detached (mechanically 
 loosened) or dissolved, to the white portions of the pattern. As a matter of 
 course cow-dung is always plentifully mixed with the urine of the animal, and 
 
MORDANTS. 295 
 
 contains a certain amount of phosphate of soda and of carbonate of ammonia, 
 which probably play an essential part. The use of cow-dung is apparently of 
 old origin, although on this subject no very precise data exist. It is known 
 that the Swiss calico-printers and dyers made use of it in the middle of the 
 eighteenth century, and M. J. Hausmann pointed out the benefits derived 
 from this material in 1790.* M. D. KcEchlin has set forth the favourable 
 effects of the dunging in the following paragraphsf : — The aim to be attained 
 by the use of cow-dung is (1), to effect the entire combination of the sub-salts 
 of alumina with the fibre of the cloth, by causing the separation of nearly all 
 the acetic acid which had not been volatilised during the drying of the 
 mordant ; (2), to dissolve and remove from the cloth a portion of the sub- 
 stances which had been used as thickeners ; (3), to separate and remove from 
 the fabric the uncombined portion of the mordant, and likewise to remove 
 such particles thereof as are simply mechanically fixed by the thickeners; 
 (4), to prevent, by the peculiar nature of the substances which constitute the 
 dung, the fixing upon the white portions of the cloth of any non-combined 
 mordant which becomes soluble by the acetic acid set free, and which acid at 
 last accumulates in the dung-bath. As for the theory of the action of the dung, 
 the clue must be sought in its composition. The labours of Morin,+ Perrot,§ 
 and Camille Kcechlin have elucidated this question to a certain degree, with- 
 out, however, solving the question completely. According to M. Morin, the 
 filtered aqueous extract of cow- dung, after having been exhausted by alcohol 
 and ether, yields to water a soluble principle which he has named bubuline, 
 and which he considers to be the active constituent, because, according to his 
 experiments, this material has the property of precipitating most of the solu- 
 tions of metals : later researches have shown, however, that the bubuline has 
 no separate existence as an immediate principle, being rather a mixture of 
 albumenoid materials, coloured by compounds due to the bile, and of vegetable 
 origin. According to M. Perrot, cow-dung from animals fed with dry fodder, 
 contains in 100 parts — 
 
 Water 69-58 
 
 Bitter principle 0*75 
 
 Saccharine matter 0-93 
 
 Chlorophyll 0-28 
 
 Albumen 063 
 
 Lignine 26-99 
 
 Chloride of sodium 0*08 
 
 Sulphate of potassa 0-05 
 
 Sulphate of lime 0*25 
 
 Carbonate of lime 0-24 
 
 Phosphate of lime 0-46 
 
 Carbonate of iron o - og 
 
 Silica <)■ i.) 
 
 100-47 
 
 * Lettre ii Berthollet, " Annales de Chimie," vol. xii., p. in. 
 
 t "Bulletin de la Societc Industrielle," vol. i., p. 313. At the time this was written the 
 ageing process, at least as now known and practised, was not used. 
 t " Bulletin de la Societc Industrielle," vol. iv., p. 1C4. 
 § Ibid., vol, viii M pp. 113 and 124. 
 

 ■ 
 
 - iwibmwbBI S9 
 
 2g6 
 
 DYEING AND CALICO PRINTING. 
 
 It would be interesting to re-examine this substance with the improved 
 means of chemical analysis now at command. To the list of the salts quoted 
 by M. Perrot must be added alkaline phosphates, which, to some extent, exist 
 in all animal excrements. M. Perrot also observed that the soluble portion of 
 the cow-dung yields in the cold an abundant precipitate with the red liquor, 
 which increases when the fluid is heated. The insoluble portion of the dung 
 retains, on being boiled with red liquor, a certain proportion of alumina. 
 M. C. Kcechlin has made some experiments with the contents of a dung-bath 
 made up in the usual manner, and therefore containing 80 kilos, dung, with 
 from 40 to 45 measures of water, temperature 70 , after there had been 
 passed through it several pieces of cloth, mordanted for good black, fine red, 
 and purple. The bath was not at all exhausted : on being left quietly standing 
 the liquid did not become clear ; there remained in suspension a black greenish- 
 coloured matter, weighing g'5 grms. for 25 litres of the liquid operated upon. 
 The filtrate had a dirty yellow colour, was astringent, and so acid as to colour 
 blue litmus-paper red. Normal dung is either quite neutral or alkaline. On 
 being evaporated to dryness the liquid left 22 - 8 grms. residue. The previously 
 suspended ligneous matter retained on the filter weighed, after, drying, about 
 28 grms. The incineration of these various substances yielded, on analysis, 
 the following quantities of alumina and peroxide of iron : — 
 
 Ligneous matter 
 
 Suspended matter (g -5 grms.) 
 
 J Alumina .. 
 
 I Peroxide of iron 
 
 ( Alumina . . 
 
 I Peroxide of iron 
 
 o t t-r / o ■; ( Alumina 
 
 Soluble matter (22 - o8 grms.H 
 
 I Peroxide of iron 
 
 o - i86 grm. 
 0-021 ,, 
 0-665 ,, 
 0-456 „ 
 o - 66o , ,, 
 o - ooo „ 
 
 It should be observed that the relatively small proportion of alumina contained 
 in the aqueous extract could not be detected by any of the usual reagents, 
 being consequently masked by the presence of organic matters. Add to this 
 the fact that the aqueous extract of a dung-bath, after it has been used for the 
 clearing of mordanted goods, contains invariably almost as much alumina as 
 the insoluble portion, yet white calico is not mordanted on being immersed 
 in this liquid, thus proving that the alumina is in an unusual condition. The 
 same applies to the iron mordants. When to a freshly-made aqueous infusion 
 of cow-dung gradually increased quantities of the acetates of iron and of 
 alumina are added, it will be seen that the precipitation does not ensue imme- 
 diately, but only appears when a certain limit is reached. There is thus good 
 reason to suppose that cow-dung contains a soluble substance, probably of an 
 albuminous nature, which possesses the property of preventing the precipita- 
 tion of the alumina and oxide of iron by the usual reagents. 
 
 According to these results the influence of cow-dung in cleansing may be 
 viewed in the following manner : — The first portions of the acetates of alumina 
 and iron which are separated from the goods remain in solution, but cannot 
 injure the white portions of the fabric, and this continues as long as the 
 masking power of the organic compounds is not exhausted. At the moment 
 of that exhaustion taking place a precipitation of the oxides ensues, in con- 
 sequence of the action of the alkaline phosphates, and when at last this useful 
 effect is also at an end all the portions of the mordant which become detached 
 can attach themselves to the white portions of the goods. It is therefore 
 
MORDANTS. 
 
 297 
 
 clear that the cow-dung owes its good effect to the fact that it contains sub- 
 stances capable of masking, or precipitating by means of double decomposition, 
 the mordants which get detached. To the saturating effect of the alkaline 
 phosphates contained in the dung is due its power of fixing upon the goods a 
 larger proportion of the oxides than would be left by a simple cleansing with 
 water. We should not overlook the utility of the insoluble substances sus- 
 pended in water. These particles play a chemical as well as a mechanical 
 part as regards the saturation due to phosphates and alkaline-earthy carbonates, 
 and take up the alumino-ferric precipitates, thereby preventing them from 
 becoming fixed to the white portions of the tissue. 
 
 Since in actual practice substitutes have been found for dung, chiefly of a 
 saline nature, — e.g., the phosphates of soda and lime, silicate of soda and 
 others, about which hereafter, all of which possess the power of saturating 
 any as yet undecomposed mordant, while they also act as precipitants for any 
 portions which may become detached, — we have, by analogy, a right to attri- 
 bute to the phosphates contained in the dung an active part. 
 
 The dung-bath is commonly made up of 30 litres of cow-dung to from 1600 
 to 2000 litres of water: dung from animals fed upon green forage, and espe- 
 cially upon beet-roots, is less useful and advantageous than the dung excreted 
 by animals fed with dry fodder. Powdered chalk is usually added to the cow- 
 dung-bath, especially for acid mordants and heavy patterns. It should be 
 noted that the mordants acquire in the dung-bath a peculiar olive-green 
 colour. This appears to be a true dyeing process, chlorophyll and some of the 
 bile pigments being deposited. It is difficult to state the number of pieces of 
 goods which can be passed through a given bulk of such a bath with good 
 effect. The number depends on the acidity of the mordants and the nature of 
 the designs, and therewith varies from 20 to 60. The duration of the immer- 
 sion has to be modified according to the concentration of the mordants and 
 the kind of thickening used, and these considerations also regulate the tem- 
 perature to be applied. When starch or farina has been used the temperature 
 should be higher than when gum is employed. It varies from 45 to ioo° C. 
 Some kinds of prints, especially if starch or farina have been used as thick- 
 eners, require two dungings and a washing between. A strong and acid 
 mordant is more difficult to dung and cleanse well than a neutral mordant, 
 and this applies especially for madder work. A too high temperature and a 
 too large quantity of dung are injurious to weak mordants, and especially to 
 rose-reds and pinks. 
 
 Great care is required in passing the goods, regularly stretched and without 
 folds or creases, and also as rapidly as possible, through the dung-bath, 
 because from the moment the hot water penetrates the cloth the acetic acid 
 leaves it, and therefore if the immersion took place slowly, and fold by fold, 
 the acid and the uncombined mordant would spread and have time enough 
 left to dissolve the alumina which had already combined, the consequence of 
 which would be inequality and deterioration of the tints to be afterwards 
 brought out in the dye-beck. After leaving the dung-bath the goods are 
 several times thoroughly washed, in order thereby to eliminate the last portions 
 of the thickeners. 
 
 Among the many substitutes for dung we enumerate the following : — the 
 double phosphate of soda and lime, the arsenites and arseniates of soda, and 
 the silicates of soda. These have lattely almost entirely displaced cow-dung. 
 

 298 DYEING AND CALICO PRINTING. 
 
 The mordanted and aged cloth is passed into weak and hot solutions of the 
 above-named substances, with the view of fixing thoroughly the mordant in 
 the cloth and removing any excess that may have been used, without allowing 
 it to fix itself on the white parts. By the introduction of these dung-substi- 
 tutes and improved vats a great saving of time, labour, and expense has been 
 effected. On the Continent bran is also used as a substitute for dung. It 
 contains a large amount of alkaline and alkalino-earthy phosphates, while, 
 moreover, the ligneous particles and other organic matters insoluble in water 
 give this substance some resemblance to dung in its mechanical action. It 
 has the great advantage of not containing colouring matters, and is therefore, 
 for light shades, preferable to dung. From 50 to 60 litres of bran are used to 
 some 3000 litres of water. The salt known as dung-substitute, chiefly made 
 and used in this country, is either phosphate of soda and lime or the arseniate 
 of these bases. From 50 to 80 grms. to the hectolitre of water are used. 
 
 There is a difference of opinion as regards the good results obtained by 
 these substitutes; experience proves that in the case of the best dung sub- 
 stitutes a final turn in cow-dung before dyeing is advantageous, it being 
 better for the mordanting oxide that it should go into the beck in a partly 
 saturated state than in a state of the highest activity. In a majority of cases 
 the colours will be more solid, brighter, and faster when the combination 
 between the mordant and the colouring matter is slow and gradual than when 
 it is rapid. Generally we may state, that with the same mordant, the dung 
 substitute gives rise to the production in the dye-beck of far deeper shades 
 of colour than when cow-dung is used. This is readily explained by the 
 more complete saturation of the mordants, when the substitute is used, and 
 the consequently smaller proportion of mordant detached from the cloth. 
 The following substitutes for finishing off the fixation of the mordants have 
 been proposed: — Ammoniacal gas (M. Wessorling) for purples, alkaline 
 bicarbonates, silicate of soda. This last substance has almost entirely 
 taken the place of dung, and since experience teaches more and more the 
 precise conditions how and where to apply it, it has even come into use where 
 its utility was most doubtful. Its mode of action is essentially saturating ; it 
 fixes all the alumina of the mordant by causing its precipitation in and on 
 the fibre before it has time to become detached. The following brief de- 
 scription of the mode of applying the silicate in madder work will give the 
 reader some idea of its use, with the observation that the prescriptions in this 
 instance, and likewise as regards all mordants and other matters of this kind, 
 although they be fit for actual use on the large scale, are not to be considered 
 as given for practice, it being a well-known fact that every manufacturer has to 
 consider his own peculiar arrangements and situation as well as the style of work 
 he cultivates. The goods pass in two minutes' time through two troughs or 
 tanks, the contents of which are heated to 50°= 122 F., and each containing — 
 for goods mordanted for brown and red, black and red, brown only, red only, 
 and rose upon a white ground — 2800 litres of water and 85 litres of silicate 
 of soda at io° B. (sp. gr. 1*075). When only mordanted for purple and black, 
 black only, and purple only, the contents of the tank are — 2800 litres of water 
 and 60 litres of silicate of soda of the above-named strength. If it happen 
 that by this treatment the colours are too deep after dyeing (a small pattern 
 may be easily tried, of course, in the dye-beck), the goods should be dunged 
 
MORDANTS. 
 
 299 
 
 a second time, using 36 litres of dung for 900 metres length of cloth, leaving 
 it for half an hour in the bath at a temperature of from 38 to 57 C. 
 
 The following example of the dunging of cloth for garancin work will give 
 an idea of the adtual operation as performed on the large scale and the in- 
 gredients employed. Goods for garancin work are, after leaving the ageing 
 room, twice dunged;* for blacks, violets, purples, greys, catechu browns, 
 reds, and puce browns the first dunging consists in passing the goods suc- 
 cessively in two minutes' time through three tanks provided with rollers, 
 and containing :— First tank — Water, 1400 litres; chalk, 125 kilos.; cow- 
 dung, 40 kilos, heated to 38° C. Second and third tank — Water, 2800 litres ; 
 cow-dung, 35 kilos.; quercitron, n to 14 kilos., heated to about 82°. The 
 second dunging is performed in one tank large enough to hold 12 pieces 
 of cloth at a time; it is left in the tank and its contents for half an hour at a 
 temperature of about 63°. The tank contains: — Water, 1200 litres; dung, 
 20 kilos. ; quercitron, 6 kilos. ; sumach, 2 kilos. For brown only, black only, 
 grey and brown together only, red and black together only, brown and black 
 together only, brown and catechu brown together only, brown and purple 
 together only, the first dunging is performed in three tanks with rollers con- 
 taining: — No. 1 — Water, 1400 litres; cow-dung, 30 kilos.; chalk, 10 kilos., 
 heated together to 38". Nos. 2 and 3 — Water, 2800 litres ; cow-dung, 25 kilos. ; 
 quercitron, 23-05 kilos., heated to 82 C. The second dunging for these colours 
 is performed also in a tank capable of containing 12 pieces of cloth at once, the 
 charge being: — Water, 1200 litres; cow-dung, 25 kilos.; quercitron, 10 kilos. 
 The whole is heated to 74 , and the goods are left for half an hour. For 
 brown and purples only a little less quercitron is taken. For garancin work the 
 dunging may also be replaced by the use of silicate of soda, but in that case 
 the colours require a stronger chlorine treatment, about which more below. 
 The use of a sal-ammoniac bath instead of dunging is only suitable when 
 aluminate of soda has been used as a mordant. 
 
 We now have to treat of the operation of dyeing with madder, an operation 
 which requires, when performed on the large scale, very great and special 
 care, and a very intimate knowledge of the conditions essential to obtain the 
 fullest, brightest, most uniform, and fastest colours, while simultaneously the 
 fullest utilisation and greatest possible exhaustion of the colouring matter of 
 the dye-stuff has to be secured. On the small scale it is easy enough to dye 
 with madder a piece of previously mordanted and dunged cloth, since it is only 
 necessary to keep the pattern (say 1 foot square) fully immersed in a bath 
 made up of 12 grms. of madder and 1 litre of water, while the temperature 
 is slowly raised to the boiling-point during the lapse of one hour's time, care 
 being taken to stir the mixture frequently in order to insure uniformity of the 
 colour. The colouring matters of the madder, while gradually dissolving in 
 the liquid contents of the dye-beck, combine with the mordants, forming 
 coloured lakes, the shade of which as well as the intensity depends upon 
 the quality and quantity of the metallic oxide fixed to the cloth. When 
 it is desired to obtain on the large scale a certain shade of constant 
 intensity (depth) the printer or dyer has to take into account a great number 
 of conditions which influence the desired result. Among these, for instance, 
 
 * Some printers dung all goods twice; first in what is called the " Dolly," and then at a 
 higher temperature in the dung-beck. 
 
Hi 
 
 300 
 
 DYEING AND CALICO PRINTING. 
 
 the composition of the water employed and the peculiar nature and richnes-s 
 of the dyeing material are prominent. All the different kinds of madder met 
 with in commerce do not act in the same way in the dye-beck, and even when of 
 the same origin its behaviour may be influenced by natural causes, good or 
 bad season, for instance, during its growth, or by adulteration. To this we 
 must add that the different commercial preparations of madder (fleur de 
 garance, garancin, &c.) each yield results peculiar to themselves, and it will 
 be clear that each of these substances requires a specially modified treatment 
 in the dyeing operation. 
 
 From these few observations it will be readily understood that a manu- 
 facturer has first and foremost rigorously to study, and next bring into practice, 
 the most suitable conditions for the duration of the immersion of the cloth, 
 the temperature to be given to the contents of the dye-beck, the mode of 
 heating, &c. 
 
 Before we review each of these conditions separately, we may yet mention 
 the following generalities: — The art of madder dyeing (French, garan^agc) 
 has been, indeed, in our days brought to so high a degree of perfection, that it is 
 difficult to think that it can be further improved. We can daily admire 
 the beautiful execution of tissues, perfectly got up, where upon a ground 
 of dazzling whiteness there are designs in rose-red, red, lilac, violet, brown, 
 or black tints, and shades of the utmost brilliancy, and, moreover, so 
 fast as to admit of strong and repeated washing. These results have 
 been obtained by the joint efforts of the many intelligent men who have 
 devoted their time and capital to this branch of industry. The introduction 
 of resin soap in the bleaching process has rendered the getting up of white 
 grounds after the dyeing process far more readily obtainable. A better and 
 more intimate knowledge of the mordants and the processes for fixing the 
 same, the substitution of the silicate of soda for cow-dung in many cases, 
 have all contributed to a more regular and more complete fixing of the 
 metallic oxides (mordants), and hence to better results ; the dyeing process 
 has been greatly benefitted by the introduction of those madder products known 
 as fleur de garance, garancin, commercial alizarin, &c. Lastly, the clearing 
 (avivagc) has become a more speedy and far more manageable operation by the 
 skilful application of chemicals. All practical dyers agree herein, that the dyeing 
 operations with fleur de garance, garancin, and similar products require less care 
 and are far more easily executed than that with madder, and therefore we will 
 turn our attention first to the latter substance, quoting succinctly the results 
 of the remarkable researches and 'labours of M. K. Schlumberger* on this 
 subject, who fully investigated one by one each of the conditions most favourable 
 to obtain good results. 
 
 First, as a necessary condition it should be borne in mind that the cloth 
 to be dyed should be thoroughly well prepared in every respect, well 
 cleared, and its mordants well fixed. As to the duration of the madder 
 dyeing, the goods may be left in the dye-beck for six hours without fear of 
 deterioration of the colours produced, but since labour, fuel for heating, and 
 loss of time are important matters, and since it is a well-known fact than an 
 equally good result can be obtained in less time and with a decided gain in 
 many respects, we may state that four hours is sufficient to all intents and 
 
 * " Bulletin de la Soeiete Industiielle de Mulhouse," vol. viii., p. 327. 
 
MORDANTS. 
 
 301 
 
 purposes when a boiling temperature is kept up for the last thirty minutes 
 of that period. It has been found that when the goods are left in the dye- 
 beck for eight hours at 50 C, more colouring matter has been extracted (the 
 madder more exhausted) than when the fabrics are only kept in the beck for 
 three hours and ebullition resorted to. This observation applies to Alsace as 
 well as to Avignon madder. When the dyeing process is continued for more 
 than six hours the colours produced stand clearing* (avivagc) less well than 
 when the time has been shorter. Since the quantity of water is of considerable 
 influence, this point was particularly investigated by M. Schlumberger, and as 
 result of his researches he concluded that 1 part of madder to 80 of water 
 was the best. When less water is taken, say 20 parts to 1 part of the madder 
 the colours produced are less fast. We have to observe here, however, that 
 on the large scale these proportions are not rigorously adhered to, and that in 
 order to save the cost of fuel and the number as well as the size of dye-becks 
 more concentrated baths than 1 to 80 are used. 
 
 As regards the quality of water we have, in this instance, chiefly to consider 
 the effects of the lime salts it may contain, and especially the carbonate of 
 that base. Taking Alsace madder as an example, that substance is acid, and 
 requires, in order to produce fast colours, the addition of some chalk to the 
 water in the dye-beck. Hence a calcareous water will not give rise to any 
 perceptible loss of colouring matter, but if Avignon madder be used, a sub- 
 stance of which we know already that it contains a certain quantity of 
 carbonate of lime, any addition thereto to the water used for dyeing will 
 certainly cause a serious loss of dye material. It is clear, therefore, that in 
 localities where the water at hand may happen to contain lime salts (car- 
 bonate or sulphate) to any large extent it will be best to purify it by con- 
 venient means or to use for filling the dye-becks the condensed steam from 
 the boilers. t According to M. Schlumberger it is best to heat the contents 
 of the dye-beck to 6o° before the goods are entered, but on the large scale this 
 arrangement would cause irregularities in the dyeing, since at that tem- 
 perature the activity of the bath is already considerable, and, moreover, ex- 
 perience has proved that the shades obtained by immersing the fabrics in the 
 bath at a too high initial temperature do not stand clearing so well as when 
 entered at lower temperatures, viz., 20 , 30, or 40 . There is some difference 
 of opinion as regards the highest temperature to be applied in order to utilise 
 all the colouring matter. According to some persons the temperature should 
 be raised to the boiling-point, but according to the author just named a tem- 
 perature of 50 for Avignon madder and 8o° for Alsace exhausts these sub- 
 stances as completely as a temperature of 95 , provided the dyeing be pro- 
 longed for eight hours. Although a boiling heat favours the fixation of the 
 
 * There is, unfortunately, too close a similarity in the English words cleansing and clearing, 
 and for that reason we have added (avivage) ; be it understood that cleansing is an operation 
 which takes place before the dyeing process, and is named in French dSgommage and bousage ; 
 though the latter term, as can be inferred from our foregoing pages, rather applies to dunging , 
 clearing (avivage) is an operation which takes place after dyeing, and is chiefly intended — 
 (1) for the washing away of dirt and superfluous colouring matter; (2) for bringing out the 
 peculiar brilliancy of the colours. The process of clearing will be fully detailed after we have 
 described the dyeing. 
 
 + Since in printing works, just as in sugar refineries, much steam is used for heating pur- 
 poses, and circulates in piping, it is not difficult to collect a sufficient quantity of pure water. 
 
—■an 
 
 t*£s< , .,<**:..-- 
 
 
 302 DYEING AND CALICO PRINTING. 
 
 colouring matter, the brilliancy and beauty of the shades produced are some- 
 what impaired, whence this maximum of temperature is often avoided in 
 practice. It is of the very utmost importance to keep the temperature of the 
 bath gradually and steadily rising, and to guard especially against a fall of the 
 heat, which is invariably attended with great loss of colouring matter. For 
 instance, if the temperature has been raised to 55 , then cooled down to 30% 
 again heated up to 70°, next again cooled to 40°, and then brought up again to 
 ebullition, there will ensue a loss of 40 per cent. The explanation of this 
 phenomenon is not easy, but since this phenomenon is not observed with fleur 
 de garance and garancin it is evident that the soluble constituents of the 
 madder play an active part in the process going on in the dye-beck. The 
 steeping of madder in water previous to use is injurious, and invariably gives 
 rise to loss of colour, not because it is thereby destroyed, since it can even 
 resist fermentation and a far advanced stage of putrefaction, but the colouring 
 matter becomes masked. When Avignon madder is thoroughly mixed with 
 a quantity of ice-cold water at o° (32 F.) and the mixture filtered, a deep 
 brown filtrate is obtained, which, when heated in the usual manner, dyes a 
 previously mordanted piece of calico very well ; but if this experiment be re- 
 peated with water at 30 , the filtrate is quite clear and does not yield any 
 dye. If Alsace madder is treated in the same way it yields at o° and at 30° 
 solutions equally rich in colouring matter and fit for dyeing. 
 
 We quote here the results of some experiments made in this direction : — 
 46 grms. each of the above kinds of madder were steeped for fifteen minutes 
 in 32 times their weight of distilled water, and next filtered with the following 
 results : — 
 
 Avignon madder. Alsace madder. 
 
 ... „ ., } 6 grms. of the material o grms. of the material 
 
 At o< dyed as well as if J » w£re used _ were use(J> 
 
 The residue on the filter j used> _ 
 
 dyed as if j J ° 
 
 Loss 10 grms. — 
 
 ..... ,, .,) 1 grm. of the material 5 grms. of the material 
 
 At 30 dyed as well as if I b , J b , 
 
 ' was used. were used. 
 
 The residue on the filter) „ „„„,„ „,_„ „„ d j 
 
 , , -r r 28 grms. were used. — • 
 
 dyed as if ' b 
 
 Loss 17 grms. — 
 
 These figures can be interpreted in the following manner: — The colouring 
 glucosides of the Avignon madder, which is neutral or alkaline, are, for a short 
 time at least, not acted upon and preserved intact at o°, but are rapidly split 
 up at 30 into an insoluble colouring matter; since Alsace madder is acid this 
 decomposition is not so rapid, and consequently the phenomena produced are 
 less sharply defined ; this observation applies to Zealand madder, which is also 
 acid. If the question be asked, what quantity of madder or any of its com- 
 mercial preparations should be used in the dye-beck, our answer is, that it is 
 difficult, if not impossible, to fix constant rules. Something depends upon 
 the greater or less fulness of the designs executed upon the cloth, upon the 
 greater or less degree of penetration of the mordant into the fibre, the greater 
 or less perfection of the ageing and fixing, the perfection also of the original 
 bleaching of the cloth, and, lastly, the greater or less strength of the mordants 
 applied. All these points influence the quantity of dye-stuff required. As a 
 
MORDANTS. 
 
 303 
 
 general rule it should be observed that the mordants ought to be saturated, 
 and since the shade desired is dependent upon the strength of the mordants 
 applied, it is evident that this condition will influence the quantity of madder 
 required. When the mordants are used too strong and their full saturation 
 not obtained (that is to say, plenty of dye-stuff present in excess), there is a 
 great risk of inequalities arising in the results. The best way to fulfil all re- 
 quirements is to have sample patterns printed in stripes with the identical 
 mordants applied to the goods attached to them when immersed in the dye- 
 beck, and therefore simultaneously dyed, and to use the results as a guide to 
 the proper quantity of dye-stuff. 
 
 According to M. H. Schlumberger's researches, mordants may within certain 
 limits be supersaturated by an excess of madder without impairing thereby 
 the brightness of the shades, provided care be taken to adjust the quantity 
 of the water in the dye-beck in due proportion to the madder. If this is not 
 properly regulated after clearing the shades obtained are spotted, unequal, and 
 dull. Contact of air does not interfere. The materials of which the dye- 
 becks are constructed exercise a great influence on the results when the 
 heating is effected by means of open fire or by a water-bath, but with the 
 application of steam the material becomes of no importance whatever. When 
 metal-made dye-becks are used heated by open fire or a water-bath it very 
 frequently happens that a loss of some 40 per cent of dye material is ex- 
 perienced, but this decrease is not observed when steam is used, and is, more- 
 over, only observed with madder, not with garancin or any other of its com- 
 mercial derivatives, and the loss is therefore due to the unequal influence 
 exercised by the soluble particles of the madder. As a general rule it may be 
 said that the addition of various substances to the dye-beck along with the 
 madder in order to increase its tinctorial power, and to attract a larger pro- 
 portion of its active principles, has never yielded favourable results. 
 
 In the paper published by M. H. Schlumberger,* and reproduced by M. J. 
 Persoz in his celebrated work "Traite de L'impression,"f will be found a long 
 list of substances drawn up by a German chemist, with the view of showing 
 the value of a large number of substances used as additions to the madder- 
 bath. It is needless to enter into further details on this subject, since ex- 
 perience has proved the uselessness of such additions, none of which, more- 
 over, have any scientific interest. 
 
 We must not, however, neglect to notice the favourable effect of a certain 
 quantity of oxalate of ammonia as an addition to the dye-beck when madder 
 is employed, as first observed by M. E. Schwartz. The addition of this salt 
 gives rise, in all probability, to a double decomposition ensuing between it and 
 the lime salts of an organic as well as of organic acids contained in the 
 madder. The colouring matter combined with these salts is thus set free, 
 while the oxalic acid seizes upon the lime. J The addition of alkalies or chalk 
 may or may not be useful according to the proportion thereof employed, and 
 the nature of the madder worked with. Since Alsace and Zealand madder 
 are both acid, the former, however, far more so than the latter, and contain 
 
 * " Bulletin de la Societe Industrielle de Mulhouse," vol. viii., pp. 293 to 360. 
 + Persoz, " Traite de L'impression des Tissus," vol. ii., p. 503 and following. 
 t We need scarcely remark that to add oxalate of ammonia along with chalk is a mere waste 
 of materials. Where either of these substances is beneficial the other is likely to be injurious. 
 
'3&a 
 
 304 
 
 DYEING AND CALICO PRINTING. 
 
 only a small quantity of calcareous matters, alkalies or chalk may be within 
 reasonable limits advantageously added to the contents of the dye-beck. As 
 regards the first-named kind, it is a known fad that it will not produce fast 
 colours without this addition. 
 
 As to the part played by chalk in madder dyeing, there can be no question 
 whatever about the advantage resulting from its addition, since on this point 
 the comparative experiments made by M. H. Schlumberger with Alsace 
 madder, with or without chalk, and with Avignon madder, which is naturally 
 rich in lime compounds, are incontestible. Zealand madder has been ex- 
 perimented with some years ago, comparatively with Avignon madder in a 
 similar manner, by a committee of practical and scientific men,* care being 
 taken (a matter of importance in such trials) to use madder of the same age 
 and maturity in both instances, while the water used was either distilled or 
 water the solid contents of which were perfectly known. The results ob- 
 tained on the large scale have proved that Zealand madder of proper maturity 
 does not absolutely require the addition of chalk, but with that addition the 
 shades produced are superior, the mordants and all conditions being alike, 
 to those yielded by Avignon madder or any other. This fact has also been 
 observed by Prof. Girardin, who along with very many in France regret that, 
 in order to please the Vaucluse madder growers, Zealand madder is practically 
 prohibited from importation by an enormously high rate of duty. As to the 
 mode of action of chalk, this may be either simply for saturating the acidity 
 of the madder, or it may actually enter into the lake to be produced, and thus 
 render the colours fast. We have already said that Alsace madder does not 
 yield shades which stand clearing well unless chalk has-been added. If the 
 saturation of the acid were the only object, it is quite clear that the precise 
 quantity required for neutralisation of the acid would suffice, but this hypothesis 
 is not in accordance with the actual results obtained by experience on the large 
 scale, which have conclusively taught that an excess of chalk is absolutely 
 necessary. Experiments made by M. D. Koechlin many years ago proved that 
 dyeing operations made with a binary mordant give rise to the production of 
 faster colours than when only a single moidant is used. M. H. Schlumberger's 
 opinion on this point is, that the chalk becomes fixed on the mordanted 
 portions, producing a binary compound of greater stability than that of the 
 aluminous substance by itself only. 
 
 The following may illustrate the meaning here briefly expressed : — When 
 a piece of cloth is first mordanted with a preparation of binoxide of tin, next 
 with an aluminous mordant, and next treated with an acid in order to dis- 
 charge again the mordants previously applied in some parts of the cloth, it 
 will be seen that after the cleansing, washing, madder dyeing, and clearing 
 operations the discharge material, acid in this case, has readily corroded the 
 aluminous mordant, and also readily enough the tin mordant wherever these 
 two were applied singly, but in all portions of the cloth where the two 
 mordants are placed upon each other no such discharging action has taken 
 place. On leaving the dye-beck the colours produced, wherever the two 
 mordants come together, are as intense and deep as if no acid had ever been 
 
 * Among them M. H. Schlumberger, jun., M. Previnaire, M. Pincoffs, M. Salomonson, 
 Professor Van der Boon Mesch, and others. These experiments were made at Haarlem, at 
 Enschede, and partly also at Rotterdam and Ghent. 
 
BINARY MORDANTS. 305 
 
 applied as a discharge at all. The eye of an inexperienced observer in 
 these matters cannot fail to detect that, after the cloth has been thoroughly 
 cleared, the shades given by the alumino-stannic mordant are far deeper and 
 far faster than those yielded by each of them separately. As a further proof 
 of the effect of the two mordants together, the clearing operation (avivage) 
 may be so far pushed as to lead to the partial destruction of the colours of 
 each of the mordants singly, whilst those of the compound mordant will be 
 found to have resisted this energetic action. The following results of ex- 
 periments confirmatory of M. Schlumberger's opinion maybe useful here: — 
 A piece of white calico was taken and mordanted with acetate of alumina, 
 the mordant was fixed and dunged, a portion was dyed with Avignon and 
 another portion with Alsace madder, and cleared. After this the pieces were 
 cut up into swatches of 50 square centimetres, and these were incinerated 
 with proper precautions. In the ash the amounts of lime and alumina were 
 quantitatively estimated, leading to the undermentioned results : — 
 
 Quantities by weight 
 in grammes. 
 
 Lime. Alumina. 
 
 i. White cotton without any preparation but bleaching. . o - oi — 
 
 2. White cotton as above, but passed through chalk-^ 
 
 milk of the same strength as that used in the dye- 
 beck, and next washed in water very slightly j 
 acidulated with acetic acid J 
 
 3. Mordanted and cleansed cloth 0*005 x ' 2 5 
 
 4. The same dyed with Alsace madder o'o6 1^27 
 
 5. The same as No. 4, but cleared 005 0^42 
 
 6. Mordanted and cleansed cloth dyed with Avignon ) _ 
 
 madder I 
 
 7. The same as No. 6, but cleared 0*17 0*21 
 
 8. Cloth properly mordanted and cleansed, dyed with\ 
 
 Alsace madder, with the addition of one-sixth of j- 0^23 1*29 
 
 its weight of chalk in the beck ) 
 
 9. The same as No. 8, but cleared o - 20 0*25 
 
 10. The same as No. 2 above, but experiment repeated . . 0-005 — 
 
 We learn, from the above-quoted results, that white unmordanted calico as 
 well as the mordanted material does not retain chalk by being passed through 
 chalk-milk, or at least does not contain any of that material after being washed 
 in water slightly acidulated with acetic acid ; but it is different during the 
 dyeing process, and after the clearing process the relation of the alumina to 
 the lime is 2 atoms of alumina for 3 atoms of lime.* During the dyeing 
 process there is dissolved alizarate of lime, which combines with the mor- 
 danted portions of the tissue. The clearing process takes away the lime, and 
 still more of the alumina, but leaves a definite compound of alizarin, lime, 
 and alumina. The analysis of the dyes obtained with oxide of iron as base 
 
 * In the opinion of many competent authorities there is little foundation for the view that 
 chalk adds to the fastness of madder co'ours, by forming a triple compound of colour, alumina, 
 and lime. In using pure alizarin the smallest quantity of lime afts injuriously, by diminishing 
 the strength of the colour. In crude madder there are not merely acids, but other colouring 
 matters, which combine with the lime and allow the alizarin to produce its full effect. 
 
 X 
 
S2Sg8ET«2 s * ■■■■■■■■■■■■■I 
 
 306 
 
 DYEING AND CALICO PRINTING. 
 
 has also resulted in the detection of the existence of a combination of the 
 mordant and lime with the colouring matter, viz., if madder had been used 
 containing calcareous matters naturally, or if chalk had been added in the 
 dye-beck. 
 
 All these observations refer to madder only. As regards fleur de garance 
 and garancin, irregularities in the mode of heating, the material used in the 
 construction of the dye-beck, and many other conditions, have no prejudicial 
 action upon the process of dyeing. Generally speaking fleur de garance can 
 be used instead of madder in all cases where clearing is required, but madder 
 is preferable for the kind known as triple pink (rose-red) ; fleur de garance, 
 
 Fig. 22. 
 
 again, is suitable for purples and blacks ; for red and black a mixture of fleur 
 and madder is used, which yields a deeper black than fleur by itself. 
 
 On the large scale madder dyeing is performed in well-constructed, water- 
 tight, wooden tanks, heated by steam, and provided with properly contrived 
 rollers moved by means of straps so as to impart to the goods stretched 
 on these rollers a suitable motion, and thereby to cause a regular renovation 
 of the points of contact between the bath and the cloth. Fig. 22 
 will give the reader some idea of this contrivance, which is also in use for 
 the dunging, branning, and soaping processes. As regards the practical 
 
MADDER STYLES. 
 
 307 
 
 execution of madder dyeing, it is of course evident that the details vary in 
 different works within certain limits, and therefore the undermentioned figures 
 have no absolute value, but may serve to illustrate the operation, while it 
 should be at the same time understood that the strict observance of the under- 
 quoted prescriptions yields excellent results on the large scale. 
 
 A. Ordinary Madder Style Work. 
 
 The previously mordanted and cleansed goods are washed in the washing- 
 machine for half an hour. 
 
 No. 1. White ground, with red and black designs : — For 900 metres of 
 cloth — 9 pieces, each 100 metres in length (100 metres are equal to 109-363 
 yards), are dyed at the same time — 10 kilos, of fleur de garance ; 10 kilos, of 
 madder ; 1200 litres of water. The temperature should be regularly raised 
 from 19 to 82 during two hours, and be kept for half an hour at the highest 
 point. If the pattern is heavy (that is to say, one which leaves little white) 
 the weights of madder and fleur should be each 25 kilos, for the same amount 
 of water. 
 
 No. 2. White ground, with a light design, puce-coloured : — 900 metres of 
 cloth: 7-5 kilos, of fleur de garance; 7^5 kilos, of madder; 1200 litres of 
 water. The temperature to be raised in two hours from 38° to 82 . 
 
 No. 3. Puce and red ; a heavier pattern upon a white ground : — 900 metres 
 of cloth : 20 kilos, of fleur de garance and 20 kilos, of madder ; and again 
 1200 litres of water. The temperature should be raised in two hours (that is 
 to say, the dyeing process performed during that time), the temperature being 
 regulated from 38° to 82°. 
 
 No. 4. White ground with a pink design : — 900 metres of cloth : 35 kilos, 
 of madder and 1200 litres of water. The dyeing process to last three hours, 
 the temperature being raised gradually during that time from 38° to 75 . 
 
 No. 5. White ground with a deep pink pattern : — 900 metres of cloth : 
 25 kilos, of madder ; 1200 litres of water. Dyeing process and temperature 
 as with No. 4. 
 
 No. 6. Rose-red pattern upon pink ground : — goo metres of cloth : 72 kilos, 
 of madder ; 1200 litres of water. Dyeing process and temperature as indi- 
 cated under No. 4. 
 
 No. 7. Lilac and black pattern upon a white ground, the colours of the 
 pattern not very deep : — cloth, goo metres : madder, 15 kilos. ; fleur de garance, 
 
 15 kilos. ; water, 1200 litres. The dyeing process to last two hours, and the 
 temperature to be gradually raised from 38 to 88°. 
 
 No. 8. Lilac and black pattern upon white ground, the design being mode- 
 rately heavy. It will be quite clear to any one who takes the trouble to inspect 
 a few hundred samples of variously printed cloths, in madder styles, that there 
 must, as regards the quantity of madder to be used, exist a relation between 
 that quantity and the quantity of mordant, which of course depends upon the 
 extent of the design in relation to the white ground left. Cloth, 900 metres : 
 
 16 kilos, of fleur and 16 of madder, with 1200 litres of water, and the dyeing 
 process and temperature as in No. 7. 
 
 Since a higher temperature has the effect of rendering the reds a bad colour, 
 pieces containing red designs are never heated higher than 82°, and preferably 
 even less. It should be observed here, also, that instead of madder, or a 
 
 x 2 
 
BiiiMMH W 
 
 THffiffMI BWBBM 
 
 30S 
 
 DYEING AND CALICO PRINTING. 
 
 mixture of madder and fleur de garance, the latter may be used alone, it being 
 borne in mind that its tinctorial value is twice as great as that of madder. 
 
 B. Garancin Style. 
 When garancin is used it is frequently mixed with a larger or smaller quan- 
 tity of lima and sapan woods, and also sumach. Patterns containing much 
 brown remain in the dye-beck or tank for two hours ; while those wherein 
 red, lilac, purple, grey-black, and catechu-brown predominate remain two and 
 a half hours. 
 
 For 12 pieces of cloth, at 100 metres each, with a full pattern, the following 
 ingredients are taken: — Water, 1200 litres ; garancin, 12 kilos. ; lima wood, 
 6 kilos. ; quercitron, 2-5 kilos. ; the temperature at the outset being 38 , but 
 raised gradually to 82 . 
 
 For black upon a catechu-brown ground : — 12 pieces of cloth : 1200 litres of 
 water ; 4-5 kilos, of garancin ; 4-5 kilos, of lima wood ; 2 kilos, of quercitron ; 
 t'5 kilos, of sumach. Temperature, from 38 to 65°. 
 
 Red ground with black and brown pattern : — Cloth, 12 pieces : garancin, 
 9 kilos. ; sapan wood, 6 kilos. ; sumach, 3 kilos. Temperature, from 38 to 82 . 
 For puce-brown only : — Cloth, 12 pieces : garancin, 6 kilos. ; lima wood, 
 20 kilos ; quercitron, 4 kilos. ; oak-bark, 4-5 kilos. ; water, 1200 litres. Tem- 
 perature, from 38 to 50 . 
 
 After leaving the dye-beck the goods are washed in the washing-machine. 
 Without entering into the details of their construction, to give some idea of 
 the vast capabilities of some of those machines we cite the following fact, 
 mentioned by Messrs. Whittaker, of Manchester. Their machine will wash 
 6000 yards (= 3 miles and 720 yards) for all kinds of dyeing purposes, and 
 12,000 yards for all bleaching purposes, per hour, only requiring the attention 
 of a person of 12 or 14 years of age. Several improved machines have been 
 introduced by a great many makers, among whom are Messrs. Mather and 
 Piatt, Mr. Furnival, Mr. Barlow, Mr. D. Crawford, all which meet with very 
 general approval. The washing in this instance is chiefly done with the view 
 of getting rid of adhering vegetable matijr. 
 
 As regards the dyeing with commercial alizarin (Pincoffs), this is performed 
 precisely as is here described for garancin. Alizarin is used for dyeing upon 
 cotton and calico in the same manner as garancin and flower of madder : its 
 properties are very similar to those of flower of madder, but the colours are 
 faster. Upon calico, double and triple purples, with black single and double 
 roses and Turkey-red (see below), are obtained as easily with this product as 
 with any preparation of garancin. The alizarin shades possess the great 
 advantage of being acted upon by soap, acids, alkalies, and preparations of 
 tin, without losing intensity, and at the same time they gain in brilliancy : it 
 is therefore necessary to use one-eighth or one-tenth less of the mordant, to 
 avoid obtaining deeper shades than would be produced by garancin or flower 
 of madder. In dyeing with alizarin the colour should be moistened with 
 warm water before being placed in the bath, otherwise it will float and perhaps 
 stain the cloth. Since alizarin does not part with its colouring principle at a 
 lower temperature than from 41 to 49 it is not necessary to pass the goods 
 into the bath below 30 to 33 , but it is better to keep them at that heat two 
 hours before proceeding to the boil : lime has a great affinity for alizarin, and 
 
GARANC1N STYLE. 
 
 309 
 
 it is therefore necessary to attend to the purity of the water to be used, neu- 
 tralising it, if required, with oxalic acid. Purpurin dyes with great facility 
 and at a very moderate temperature ; the bath is perfectly clear, and may 
 serve until exhausted. 
 
 Upon calico, red and black mordants are dyed very quickly ; a weak soap 
 bath (clearing) of from 44 to 49 restores the whites and brightens the colours. 
 Purple mordants take the colour with the same facility, but the shades are 
 somewhat greyish. In order to fasten purpurin colours and preserve the 
 whites it is necessary to mix purpurin with from fifteen to twenty times its 
 weight of bran and a sufficient quantity of water at about 40 , and add it to a 
 bath at about 55 , which is then heated so as to boil in about forty-five 
 minutes, and kept boiling for the same time, during which the pieces are 
 passed into it, and afterwards into a boiling bran bath ; after which a simple 
 washing will suffice to render the whites perfect. 
 
 To prepare a steam-colour with purpurin, for cloth mordanted with an 
 aluminous mordant, the following is the best plan :— To the purpurin is added 
 20 per cent of its weight of carbonate of soda ; the whole to be well ground 
 together ; hot rain-water is added, when a magnificent red solution is obtained, 
 which is filtered and left to cool. It is then thickened with starch to the 
 required consistence, and maybe preserved without alteration for a long time. 
 When required it is printed, steamed, and washed in cold water. With 
 20 grms. (about 300 grains) of purpurin per quart a good colour is obtained. 
 If in filtering the purpurin solution there is any deposit on the filter, it may 
 be used in ordinary dyeing. 
 
 We have now to direct our attention to the operation known as clearing 
 (avivage) : the colours obtained with garancin, alizarin (commercial), and 
 purpurin are sufficiently pure and also quite brilliant enough not to require the 
 operations necessary for madder-dyed stuffs for increasing or bringing out 
 these properties. All that is required is a thorough washing, in order to 
 restore to the whites the proper degree of purity. This purpose is attained 
 by the application' either of soap or of a bran bath, the latter chiefly applied 
 to garancin browns (puce-colour), and to such patterns on white ground as do 
 not contain purple. This branning is, strictly speaking, an avivage,* but one 
 of a very mild character as compared with that in general use for madder-dyed 
 materials. 
 
 For a puce ground, without any purple design, the following ingredients are 
 used for 18 pieces of goods, at 100 metres each : — Water, 1200 litres ; bran, 
 q kilos. ; cow-dung, 25 kilos. Temperature, 56 ; duration of the bath, i.e., 
 time of keeping goods in, 30 minutes. 
 
 For goods with white ground, without purple, again for 18 pieces: — Water 
 1200 litres; bran, 9 kilos.; cow-dung, 1-5 kilos. Temperature, from 38 to 
 57 ; time, 30 minutes. 
 
 Branned goods are not afterwards soaped, but simply washed in the washing- 
 machine for half an hour, with cold or tepid water. Soaping — that is to say, 
 the immersion of the goods into a more or less concentrated soap solution, at 
 a more or less high degree of heat, sometimes raised to the boiling-point of 
 water — is performed, with garancin-dyed articles which contain purple, for the 
 double purpose of better fixing that colour and for increasing its brightness. 
 
 * Literally, a rendering more lively, and this signification is not precisely implied in the 
 word clearing. 
 
wMWttaBBBBdtUm 9HHH 
 
 310 DYEING AND CALICO PRINTING. 
 
 For goods containing much purple the soap solution consists of 8 kilos, of 
 white soap and 1320 litres of water : temperature, 100° ; duration of immer- 
 sion, 1 minute. For goods with less purple the quantities are — Water, 1320 
 litres ; white soap, 4 kilos. : temperature and time of immersion the same as 
 above.* 
 
 These operations — viz., washing, branning, and soaping — are not sufficient 
 to bleach very completely the unmordanfed or the white portions of the fabric 
 which have taken up, even in garancin-dyeing, some colouring matter, although 
 far less so than is the case with crude madder. The goods are therefore sub- 
 jected to the a&ion of chlorine, — that is to say, run through a very weak 
 solution of bleaching-powder. Garancin-dyed articles are chlored twice ; 
 the first operation, steam chloring, consists in passing the goods first through 
 a very weak solution of bleaching-powder, and immediately after through a 
 large tank filled with steam : the moist heat sets the chlorine (hypochlorous 
 acid) free, and thereby causes the oxidation of the small quantity of colouring 
 matter adhering to the white portions of the fabric. 
 
 It need hardly be said that the solution of bleaching-powder should be so 
 dilute as not to injure the tissue, even very fine muslins and similar fabrics, 
 and also not to deteriorate the colours. The second chloring is effected by 
 making the goods, after having been moistened with the solution of bleaching- 
 powder, pass over a series of partly hollow cylinders, heated by means of 
 steam, whereby, during the drying, the bleaching also is completed. We give 
 below some receipts as employed for these purposes, but in this country the 
 aqueous solution of chlorine is not very commonly used, owing to the fadt 
 that it is a less certain agent, unless prepared with great care and used 
 within a very brief time after it has been prepared. 
 
 For goods containing much purple the solution for the first chloring consists 
 of — 50 litres of water ; 2 litres of chlorine water ; 16 grms. of ultramaiine : 
 the latter substance performs here the same functions as the various kinds of 
 blues used in the laundries. The second chloring solution consists of— Water, 
 16 litres ; chlorine water, 2 litres ; ultramarine, 2*240 kilos. 
 
 For puce-brown coloured ground with a white pattern the first chloring is 
 made up of — 12 litres of water ; 2 litres of chlorine water ; 15 grms. of ultra- 
 marine. Second chloring solution : — Water, 16 litres ; chlorine water, 2 litres ; 
 ultramarine, i'i2o kilos. 
 
 For grey dyed goods, first chloring liquid : — Water, 24 litres ; chlorine 
 water, 2 litres ; ultramarine, 15 grms. Second solution : — Water, 120 litres ; 
 chlorine water, 2 litres ; ultramarine, 1 120 kilos. 
 
 For goods with much red, first solution : — Water, 40 litres ; chlorine water, 
 
 * The soap for clearing madder purples is generally selected less alkaline than that used 
 for reds and pinks. For the former a good composition is — 
 
 Fatty acid 60*40 
 
 Soda .. .. .. 5 - 6o 
 
 Water 34*00 
 
 ioo-oo 
 For reds and pinks the following is preferable :— 
 
 Fatty acid 59*23 
 
 Soda .. .. .. .. .. .. 677 
 
 Water . . . . . . . . . . . . 34'oo 
 
 IOO'CO 
 
GARANCIN STYLE. 
 
 3" 
 
 2 litres ; ultramarine, 15 grms. Second solution : — Water, 40 litres ; chlorine 
 water, 2 litres; ultramarine, IT20 kilos. 
 
 For goods dyed when much catechu has been added to the garancin, the 
 first chloring solution consists of — Water, 24 litres ; chlorine water, 2 litres ; 
 ultramarine, 15 grms. Second solution : — Water, 60 litres ; chlorine water, 
 2 litres ; ultramarine, i - i2o kilos. 
 
 Goods dyed with the same colours, but with white ground, are treated in 
 the same manner, but the ultramarine is dispensed with. It is quite evident 
 that the chlorine water used should be pure, and quite free from hydrochloric 
 acid. 
 
 Fig. 22 gives an idea of the arrangement of the rollers or cylinders above 
 alluded to. 
 
 When chloride of lime or bleaching-powder is used it is applied in several 
 ways : madder-dyed goods for clearing are run through a very dilute hot solu- 
 tion of the bleaching-powder, until the dyer or clearer considers the whites 
 sufficiently restored and bright. For garancin-dyed fabrics the same process 
 may be adopted, but experience has shown that the higher temperature 
 employed in garancin-dyeing tinges the whites more deeply than madder, 
 while the less stability of the colours produced renders it dangerous to let the 
 pieces run long enough to clear the whites. In consequence, two other 
 methods of clearing garancins are adopted : — The first consists in padding 
 the piece to be cleared in solution of bleaching-powder, at a specific gravity 
 of from i - 075 to roio : the padding is done by an engraved roller, and so 
 arranged that only a small quantity of the bleaching-liquor is transferred to 
 the piece, which is next passed over the steam-chest or drum, and either 
 washed off or finished without washing. The other and better method con- 
 sists in padding the pieces in bleaching-powder solution not quite so strong as 
 the last, and then passing them through a steam box, in which they remain 
 two or three minutes exposed to low pressure steam, and from this pass 
 through three or four boxes of water to wash them. The only delicate point 
 in clearing is to hit such a strength of the clearing liquor as shall effectually 
 clear the whites without acting too much upon the coloured portion. In light 
 shades this is not an easy matter, and it is therefore preferable to clear them 
 in the beck, where they can be watched. 
 
 The application of chlorine instead of grass bleaching for garancin-dyed 
 goods was first introduced into Fiance in the year 1847 by Messrs. Blech, 
 Steinbach, and Mantz. A very great saving of time and money is the 
 result, along with a far better finish of the goods. A fact which could not 
 have been foreseen, viz., that the dyed portions of the cloth are less readily 
 and plentifully moistened by water than the white portions, contributes largely 
 to the proper action of the chlorine, which consequently has more effect upon 
 the white than upon the coloured parts of the tissue. After the chloring the 
 goods are ready for being starched and blued, and calendered, as the case may 
 require, and finished for packing. When madder-dyed goods leave the beck 
 the white portions of the fabric are very much soiled, the colours are flat, 
 without life or brilliancy, and are not quite so fast as is desirable. The 
 operations by means of which the beautiful results with which the public is 
 familiar are obtained are of a complex nature, and vary for different styles. 
 The reds, lilacs, and purples do not stand equally well the action of the same 
 

 312 
 
 DYEING AND CALICO PRINTING. 
 
 chemical agents — what beautifies the one injuring the other; so that if both 
 these colours occur on the same piece the beauty and brilliancy of one of 
 them will be of necessity sacrificed to the other. 
 
 Even as late as the middle of the first quarter of this century field bleaching 
 and boiling the goods in bran-water were the chief modes of clearing in use. 
 The application of soap for clearing purposes dates from the year 1804, when 
 it was first used by M. D. Kcechlin, who also appears to have occasionally 
 employed chlorine. 
 
 The modern processes for clearing madder-dyed goods have been gradually 
 developed, and are more the result of accidental discoveries than of a regularly 
 studied course of research. For clearing of rose-reds and reds by themselves 
 almost every printer and dyer has his own peculiar method, but generally 
 the following is an outline of the process applied :— Soap baths, a tin-salt 
 bath, and a boiling up of the goods under pressure with crystallised carbonate 
 of soda and soap. The ingredients used and their proportions may be learnt 
 from the undermentioned examples: — 1. Soap bath — Water, 1200 litres; 
 white soap, 4 kilos, for 900 metres (g84 - 267 yards) of cloth ; temperature, 56 ; 
 time of immersion, one hour and a quarter. 2. Washing in machine with 
 cold water. 3. Bath of nitro-muriate of tin (perchloride of tin)— Water, 
 800 litres; solution of the tin preparation, 1-5 litres for 300 metres of cloth ; 
 temperature from 56" to 62 ; time of immersion, from fifteen to twenty 
 minutes. 4. Washing in machine as in No. 2. 5. Second soap bath — Water, 
 1200 litres; soap, 3 kilos.; cloth, 900 metres; temperature, 94 ; time, three 
 quarters of an hour. 6. Again washing in cold water. 7. Third soap bath — 
 Water, 1200 litres; soap, 3 kilos.; cloth, 900 metres; temperature, 94 ; 
 time, three quarters of an hour. 8. Another washing in cold water. 9. 
 Boiling in a closed boiler under pressure — Water, 1200 litres; soda crystals, 
 2-5 kilos. ; soap, 2-5 kilos. ; time, two hours. 10. Again washing in cold 
 water. 11. Warm bath at 50 during thirty minutes' time. 
 
 Field bleaching in combination with some of the above operations is still 
 in use for certain styles, chintzes, and furniture prints, because the tints be- 
 come more transparent. As regards the action of these different operations, 
 at the first soaping the goods lose much colouring matter; the liquid, indeed, 
 becomes rather deeply red. This is partly due to the colouring matter, which 
 had been temporarily fixed to the white portions of the tissue, and partly also 
 to such of the constituents of the madder as yield less fixed permanent 
 colours than alizarin, viz., purpurin, and, more so, pseudopurpurin combined 
 with the mordant while in the beck. 
 
 Dr. Schutzenberger has demonstrated that properly mordanted cloth dyed 
 by means of pseudopurpurin yields to a soap bath the greatest portion of its 
 colour. Soap, moreover, has the effect of dissolving the greater part of the 
 yellow matters, which cause the dulness of the colours. The action of the 
 soap is not simply detergent, for in consequence of a more or less complete 
 decomposition of the soap,* a portion of the fatty acid is precipitated on the 
 tissue, and combines either chemically or mechanically by a strong adhesion 
 with the coloured lake, thereby communicating to that substance a far greater 
 fastness and power of resisting the action of light and solvents than it 
 
 * The reader is reminded that soap is in a chemical sense a salt made up of a base and 
 a fatty acid. 
 
CLEARING MADDER STYLES. 
 
 313 
 
 previously possessed. That this effect is really caused by the soap is proved 
 by the fact, that if the dyed fabrics, on being taken from the dye-beck, after a 
 wincing in cold water for the removal of adhering particles of dye-stuff, were 
 immediately placed in a bath of nitro-muriate of tin, the colours would be far 
 more attacked than is the case in the ordinary process of clearing. By the 
 treatment with the tin preparation, instead of which very dilute nitric acid 
 may be used, a remarkable effect is produced. While undergoing this treat- 
 ment the reds and pinks seem almost destroyed, becoming orange, but by the 
 subsequent soap bath the fine shades are brought out very vividly, exhibiting 
 also a peculiar "bloom," which before the application of the tin-salt bath was 
 not seen at all. The intensity of the colour is, however, slightly diminished, 
 but this effect is taken into consideration during the dyeing process, care being 
 taken to procure rather too deep a colour. 
 
 The experiments of Schlumberger have proved that the acid of the tin bath 
 takes away a small portion of the alumina, while also some of the oxide of 
 tin becomes fixed, the acid, moreover, removing the last portions of yellow 
 matter. M. Persoz has thought that the tin bath might perhaps have a 
 peculiar effect upon the principal colouring matter by entirely altering it, 
 but this view is certainly not well founded, since more recent experience 
 has proved that pure alizarin may be extracted from dyed fabrics which have 
 been submitted to the clearing operations. It is far more likely that the 
 effect of the nitro-muriate of tin is the complete elimination of the purpurin, 
 pseudopurpurin, and the yellow colouring matters. The two former sub- 
 stances yield with aluminous mordants a red, less bloomy, bright, and vivid tint 
 than is produced by alizarin, and therefore the peculiar effects of the tin bath 
 are readily accounted for. To this should be added, that the fixing of some 
 oxide of tin instead of the eliminated portion of alumina plays an important 
 part. The second soap bath also, at nearly boiling heat, does not simply act 
 as detergent, but it is probable that again some of the fatty acid is fixed. As 
 regards the action of the last boiling under pressure, it is very difficult to ex- 
 plain precisely what it effects. According to M. Persoz, the effect is the fixing 
 of a larger quantity of fatty matter, and there is good reason to adopt 
 this as a correct view. It is supported by the following facts : — Red 
 madder-dyed cloth, which has either not been cleared at all or only incom- 
 pletely so, turns, on being treated with acids, an orange-red, and, on being 
 next immersed in milk of lime, becomes bluish ; but after a complete process 
 of clearing, and especially after the boiling under pressure, as described, the 
 cloth stands the action of these agents without thereby undergoing any per- 
 ceptible change ; the effect, therefore, produced by the said boiling is some- 
 what analogous to the well-known properties of the so-called Turkey-red, 
 which, as we shall presently see, owes its great power of resistance to the 
 presence of a modified fatty substance in combination with the aluminous 
 lake. The clearing of the purples, puce browns, and blacks, where no red is 
 present on the cloth, requires, for bringing out all the beauty of these colours 
 in the highest degree of perfection, the agency of chlorine or of bleaching- 
 powder. Without doubt the main action of the hypochlorites of lime, of soda, 
 and magnesia, as industrially applied, is oxidising. It is very probable that 
 the iron mordants undergo in the dye-beck a partial reduction, and that the 
 proper degree of oxidation required is restored by the application of the hypo- 
 
wmmmmmmmmmmm 
 
 
 ■BBBBBHB 
 
 314 
 
 DYEING AND CALICO PRINTING. 
 
 chlorites. On the other hand, the colouring matter itself is certainly not 
 acted upon in this way, since it is possible to extract pure alizarin from cloths 
 dyed purple, lilac, and brown, and cleared. When pincoffin is used as a 
 dye material the purples produced require no clearing at all, and the ex- 
 planation may be, that either the stronger heat applied has had the effect of 
 destroying the foreign matters which, while becoming fixed to the mordant, 
 affect the purity of the colours, or this overheating neutralises the reducing 
 effect of the organic substances, and as a consequence the peroxide of iron 
 of the mordant does not undergo a partial reduction, and therefore the appli- 
 cation of chlorine is needless. Instead of the nitro-muriate of tin, which 
 would injuriously affect the purples, browns, and blacks, sulphuric or oxalic 
 acid is applied, but their use should be avoided wherever possible, since even 
 without these the clearing process affects the browns and blacks. 
 
 For purples, lilacs, browns, and blacks alone the ingredients and quantities 
 are as follows: — Cloth, 900 metres; water, 800 litres ; solution of chloride of 
 lime (sp. gr. ro6o); temperature, from 50 to ioo° ; time, quarter of an hour. 
 Washing in machine with cold water and next the first soap bath: — For 
 goo metres of cloth — Water, 1200 litres ; soap, 4-5 kilos. ; temperature, 88 c ; 
 after the first half hour another 1*5 kilos, of soap are added, and the operation 
 continued for a further quarter of an hour. Again a washing in the machine, 
 followed by second chlorine bath of the same composition as the first, but 
 the temperature from 50 to 63 ; time, twenty minutes. Again a washing in 
 the machine with cold water. Second soaping, for 900 metres of cloth : — 
 1200 litres of water and 2 kilos, of soap; temperature, 94°; time, twenty 
 minutes. Again a washing, followed by a bath of bleaching potassa liquor* 
 composed of — Water, 1200 litres; carbonate of soda, 4 kilos.; potassa 
 bleaching liquor, 10 litres ; for 900 metres of cloth at a temperature of 56 , 
 and to last for twenty minutes ; this treatment is followed by washing in cold 
 water in the machine and next drying. No acids are employed, the operations 
 being performed with the aid of soap and the hypochlorite. 
 
 When red, brown, and black are printed on the same cloth the clearing opera- 
 tions are conducted as follows: — First, a bleaching bath composed of 800 litres of 
 water and 4 litres of bleaching-powder solution at 1-060 sp. gr. for 300 metres 
 of cloth ; temperature, from 31 to 44 ; time, fifteen minutes. Second, washing 
 in the machine, followed by the first soap bath, composed, for 900 metres of cloth, 
 of — Water, 1200 litres ; soap, 4 kilos. ; temperature, from 44°t0 56°; time, three 
 quarters of an hour. Again a washing in cold water, and next, if the black is 
 &iill deep enough coloured, a bath of nitro-muriate of tin. but if the black will 
 not stand this a bleaching bath is applied made up, for 300 metres of goods, 
 of 800 litres of water and 4 litres of bleaching-powder solution at i - o6o sp. gr. ; 
 temperature, 44 ; time, twenty minutes. After this again a washing in cold 
 water, and next the second soap bath, consisting of — Water, 1200 litres; soap, 
 3 kilos., for 900 metres of cloth, to be kept at a temperature of 94" for fully 
 three quarters of an hour. Another washing in cold water is followed up by 
 a third soap bath made up of — Water, 1200 litres ; soap, 2*5 kilos., for 
 900 metres of cloth ; temperature, 94 ; time, again three quarters of an hour. 
 Again washing in cold water, followed by the third bleaching-powder bath, 
 
 * A liquid somewhat akin to the well-known Eau de Javcllc (hypochlorite of soda), but con- 
 taining potassa instead. Magnesia will be found preferable. 
 
MADDER PRINTING. 
 
 315 
 
 consisting, for 300 metres of cloth, of 800 litres of water, 1-25 kilos, of soda 
 crystals, and 5 litres of bleaching-powder solution at ro6o sp. gr. ; tem- 
 perature, 50 ; time, thirty minutes. Again a washing in cold water, and, 
 lastly, drying ends these operations. 
 
 When purples, lilacs, red, and black are printed on the same piece the 
 clearing operations and ingredients used are the same as just described, but 
 
 instead of the bleaching-powder bath use is made of a bath made up of 
 
 Water, 1200 litres ; crystals of soda, 4 kilos. ; potassa bleaching liquor 
 (hypochlorite), 10 litres, at a sp. gr. of 1-044; cloth, 900 metres; temperature, 
 38° to 44 ; time, twenty minutes ; washing and drying. The dry goods are 
 calendered,* next starched and blued, dried, and a second time calendered. 
 Purple grounds and white designs require a larger quantity of ultramarine blue. 
 
 We have now to consider a totally different application of the colouring 
 principles contained in madder, which may be explained in a few words, first, 
 as follows: — Instead of printing on the mordant and immersing the prepared 
 cloth bodily into a dye-beck containing the madder, the colouring matter 
 itself is printed on to the cloth, after having been brought into a suitable state 
 of solution. In this instance we meet with three distindt modes of application; 
 either the cloth itself is first thoroughly mordanted all over with acetate of 
 alumina or any other required mordant; or the colouring matter and the 
 mordant are so prepared as to form together the elements of the lake to be 
 fixed to the cloth; or, lastly, the lake previously and separately prepared, and 
 in an insoluble state, is fixed by means of a plastic mordant, as, for instance, 
 albumen. The first experimental trials in this direction were made in the 
 year 1827 by Messrs. Robiquet, Colin, Lagier, and Persoz ; but not before ten 
 more years had elapsed did M. Gastard, at Colmar, succeed in printing on 
 the large scale the colouring matters of madder upon previously mordanted 
 cloth. It need hardly be observed that in this mode of proceeding there can 
 be no question whatever about the use of madder or any of its preparations, 
 such as garancin, for instance, since all of these contain the ligneous inert 
 fibre, and therefore the concentrated extra&s of madder can only be applied 
 in this instance. M. Gastard has proposed two methods of operation for this 
 purpose — (1) the thorough mixing of colorin (a very rich alcoholic extract of 
 madder, formerly made by Messrs. Lagier and Thomas at Avignon) with gum 
 or starch paste and acetate of alumina, and steaming after it has been printed 
 on the cloth ; (2) the cloth is mordanted all over with acetate of alumina 
 (preceded sometimes by an oiling operation, about which further details will 
 be given under the head of Turkey-red), the mordant is fixed as usual, the 
 thickened colorin is printed on the fabric, which is next steamed, and afterwards 
 cleared as for reds and rose-pinks. This operation may be also performed 
 with iron mordants as for brown ; in that case the ground colour of the cloth 
 will be coloured by the mordant itself, but this buff may be removed by 
 passing the cloth through a tepid solution of bitartrate of potassa. The 
 rather high price of the colorin has been the great obstacle in the industrial 
 execution of this process on the large scale. In the year 1838 M. Fauquet 
 
 * That is to say, undergo an operation which, in effect, is the same as the ironing of linen 
 made up for use as clothing, but which in this instance consists in passing the goods between 
 two well-polished and bright cylinders made of copper or steel and heated by steam internally. 
 

 ■ &€2S2jg.$! i^^^m 
 
 !'i V* ■■■ 
 
 h HffHHff yBBBHBRHTBBHB 
 
 316 
 
 DYEING AND CALICO PRINTING. 
 
 obtained a brevet d 1 invention* for an application of an improved extract of 
 madder, and Messrs. Girardin and Grelley made successful experiments on the 
 application of their ammoniacal solution of colorin thickened with gum. 
 After steaming the cloth so treated had only to be washed in cold water. 
 This process had the additional advantage of being applicable to fabrics the 
 grounds of which had been dyed black by means of logwood, or brown by 
 means of catechu, both of which colours do not stand the clearing process. 
 None of these trials and experiments ever came really into general practice, 
 and only as late as the year 1855 was introduced what is known as 
 M. Hartmann's method, which has been used to a limited extent by the firm 
 of Schwartz-Huguenin at Mulhouse, although this method has been entirely 
 superseded by another invention due to M. Pernod. 
 
 We record here the manner of its execution according to the statements of 
 M. Al. Rack. The cloth is mordanted with acetate of alumina, first, by being 
 passed through a solution of that salt at 1-022 sp. gr.; next dried, aged at ordinary 
 atmospheric temperature for twelve hours, cleansed by means of silicate of soda, 
 and further proper treatment, and next dried, after which comes a second 
 mordanting in a bath of acetate of alumina at 1*036 sp. gr., followed by the 
 same cleansing and other operations. The colouring matter (an alcoholic 
 extract of madder) used to be incorporated with soap solution, but since the 
 so-called green alizarin was discovered, this latter substance in the state of 
 undried paste, and containing from 60 to 70 per cent of water, has been sub- 
 stituted for this extract. 
 
 The dried green alizarin can also be employed for this purpose, after having 
 been previously mixed (in the proportion of 65 parts of soda solution and 35 of 
 alizarin) with a solution of caustic soda at 1-007 S P- 6 r -t When the undried 
 pasty green alizarin is used there are added to 1 litre of this material 25ogrms. 
 of gum, previously reduced to powder. This mixture keeps well. For the 
 purpose of colour printing the following mixture is employed : — 1 litre of 
 thickened alizarin ; 0-4 litre of warm soap lye, prepared with 100 grms. of 
 soap to the litre ; 1 litre of gum water. This mixture has to be applied at 
 once, because it is liable to be spoiled by the coagulation of the soap. Some- 
 times, also, this mixture is diluted by taking 1 kilo, thereof, and mixing this 
 with 1 kilo, of a thickening fluid consisting of 4 litres of gum water and 1 litre 
 of hot soap solution containing 100 grms. of soap ; or, again, 1 kilo, of the 
 alizarin mixture with 1250 grms. of the thickener. After the printing and 
 drying the cloth is steamed for two hours, next washed with clean cold water, 
 in a running stream if possible, and next soaped at a temperature of 20 . Tf 
 required a cold and weak bleaching-powder bath may be applied. 
 
 The purpurin and yellow alizarin discovered by M. Kopp may be employed 
 for colour printing purposes by being first dissolved in weak caustic soda 
 solution, next thickened and printed on to properly mordanted fabrics, and, 
 lastly, steamed. 
 
 As regards the printing of madder lakes and the fixing thereof on cloth 
 
 * " Technologie dc la Garance," par M. Girardiu (at present Doyen de la Faculte des Sciences 
 at Lille), Paris, 1844. 
 
 t This amounts to a quantity of less than 1 per cent of dry caustic soda, since, according to 
 the tables collocated by Dr. Gerlach (see " Chemical News," vol. xxi., p. 155), the sp. gr. of an 
 aqueous solution of that alkali at 15 equal to I'oia holds exactly 1 per cent of the dry substance. 
 
DISCHARGE AND RESIST PROCESSES. 
 
 3i7 
 
 by means of animal mordants, such as albumen, this has never been a 
 successful operation, for the very good reason that the madder lakes, even the 
 best prepared, when thus employed, do not exhibit the same transparency and 
 pleasing effect as the dyed colours produced by madder; it is, moreover, very 
 difficult to prepare deep red madder lakes, while hitherto neither purple nor 
 brown madder lakes have ever been made with anything like a satisfactory 
 result even to serve as pigments. 
 
 We cannot enter fully into the details of the so-called discharge and resist 
 processes destined to produce white patterns on a coloured ground ; but although 
 this subject is in reality a speciality of technology, and therefore requiring a 
 separate treatise, it is hoped that the following particulars will give the reader 
 some idea of these operations. By the word discharge (cnlevage in French) is 
 designated any compound or mixture which has the property of bleaching, or 
 taking away, the colour already communicated to a fabric. Their use as regards 
 madder-dyed goods is chiefly confined to the Turkey-red dyed fabrics, but is appli- 
 cable if required upon lilac and other madder shades. The process generally 
 known as Monteith's consists in the direct application of a solution of chlorine 
 to the dyed fabrics. The Turkey-red dyed fabrics are placed in folds properly 
 smoothed and arranged between two thick cast lead plates, both of which are 
 perforated with the design to be produced, the perforations exactly corres- 
 ponding; the cloth is then pressed between these plates with considerable 
 force, and the plates secured. By this mechanical contrivance the wetting of 
 the portions of the cloth tightly pressed between the unperforated parts of the 
 plates is very effectually prevented, while any liquid poured on the upper 
 plate will gradually filter through the cloth from the perforation of one plate 
 to the corresponding on the other. The passage of the discharging fluid 
 (bleaching-powder with an excess of free acid) is assisted by currents of 
 air. When the colour is discharged clear water is passed through, and the 
 pieces then washed and finished. As might be expected from the nature of the 
 process, the edges of the design are not sharp and clear, because, notwith- 
 standing any practical amount of pressure, capillary attraction will assert 
 itself, and consequently the edges of the designs are blurred. 
 
 The other process frequently used for this purpose is the discovery of 
 M. D. Kcechlin and Mr. Thompson. It consists in printing a highly acid 
 colour upon the cloth to be discharged, and then plunging it into a solution 
 of bleaching-powder in water ; the acid acts upon the bleaching-powder, 
 causing a disengagement of chlorine, which destroys the colour upon the spot 
 where the acid is printed. It will be readily understood that the difficulty in 
 this process consists in confining the discharge to the points printed on, for 
 it is not possible to hit the quantity of chlorine just necessary to discharge 
 the colour, and any excess generated spends itself upon the colour in the 
 neighbourhood, unless some precautions are taken. By having a considerable 
 excess of lime (chalk may be added with some advantage) in the bleaching- 
 powder, and by not leaving the goods in any longer than is absolutely required, 
 and also by care being taken that the cloth is properly dried before being 
 immersed in the bleaching solution, very regular results can be obtained. 
 Besides producing a white design, there are discharges which, whilst de- 
 stroying the red colour, leave another in its place, or the basis for producing 
 another. As examples of the composition of some of these discharges, we 
 
rammr- — — 
 
 318 
 
 DYEING AND CALICO PRINTING. 
 
 quote the following : — White discharges on Turkey-red — 1 ga'lon of water ; 
 10 lbs. of tartaric acid ; 7 J lbs. of pipeclay or china-clay ; 1 pint of gum water ; — 
 i£ lbs. of bichloride of tin ; 1 gallon of hot water; 9 lbs. oi tartaric acid ; 10 lbs. 
 of pipeclay ; 3 quarts of gum Senegal water. These can only be properly 
 applied by blocking, but the following discharge for machine work may do for 
 light designs: — 1 gallon of water; 6 lbs. of tartaric acid ; ij lbs. of starch. 
 As an instance of discharge for red and the reproduction of blue on the dis- 
 charged spot, we mention the following mixture : — 2 gallons of muriate of 
 tin; 1 gallon of prussian blue pulp;* 1 gallon of water ; 5 lbs. of tartaric 
 acid, to which, after having been dissolved and mixed together, are added 
 2 gallons of thick tragacanth gum water. The excess of acid discharges off 
 the red, while the blue part not being acted upon, remains. 
 
 A resist (French, reserve) in calico printing signifies any suitable composition 
 applied to the portions of the fabric in order to prevent the decomposition of 
 the colour or mordant upon those portions of the cloth. The parts thus pro- 
 tected may be either the original white fibre of the cloth, or it may be some 
 coloured part which is required to be preserved unaltered, while the remainder 
 is covered with some coloured design. Resist compositions intended for this 
 latter purpose are usually called pastes, and the colour so preserved is said to 
 be pasted ; resists may, moreover, be either chemical or mechanical, or both 
 combined, according to the nature of the colour or mordant to be resisted 
 and the manner in which it has to be applied. The best and only safe resist 
 for iron and red liquor mordants is lime-juice, chiefly citric acid. If of fair 
 quality and of proper strength it leaves nothing to be desired. Good lime- 
 juice at 15 Tw., thickened with calcined farina, will resist all the iron and 
 alumina mordants in use for madder work, and at 30 Tw. it is strong enough 
 as a resist for garancin styles. Oxalic and tartaric acids and bisulphate of 
 potassa will act as resists, but are inferior to lime-juice or citric acid. Citrate 
 of soda or potassa also form a good neutral resist, and are usually employed 
 along with pipeclay. 
 
 The reserves or protecting resists are commonly applied by the block, and 
 act chiefly mechanically, as may be inferred from the undermentioned resist 
 paste for chintz, made up of — Water, 6 gallons ; neutral arseniate of potassa, 
 15 lbs. ; pipeclay, 40 lbs. ; calcined farina, 30 lbs. The arseniate of potassa 
 has some resisting power, but its use in combination with pipeclay is owing 
 to its drying up in a dense, somewhat gummy mass, which gives solidity to 
 the pipeclay, and makes it more capable of withstanding the effects of friction. 
 Another neutral paste is made from citiate of soda mixed with pipeclay and 
 calcined farina. 
 
 A most ingenious means of obtaining reserves on fabrics is the invention of 
 Messrs. Onfroy and Co., of Paris : this process is the more advantageous, because 
 the chemical reserves in general use are imperfect in composition, of difficult 
 application, and still more difficult to remove. The process in question con- 
 sists in punching out patterns from a sheet of cardboard lined with gutta- 
 percha in such places as are intended to remain white or reserved. The card- 
 board is then rolled on the pressing cylinder of the printing machine, so that 
 
 * Under this name are known to printers and dyers a variety of mixtures made up of yellow 
 prussiate of potassa (ferrocyanide of potassium), protochloride of tin, or bichloride and water. 
 
RESERVES. 
 
 319 
 
 when the machine is working the parts of the pattern which have been cut 
 out receive the impression, and thus form the reserve parts of the pattern. 
 It is evident that to obtain satisfactory results the greatest precision must be 
 observed in applying the cardboard to the pressing cylinder, so that the 
 engraving roller will only press where required. The great advantage of this 
 mode of producing reserves is that, by employing a pressing roller of sufficient 
 diameter, reserves of large surface can be easily obtained. Under the name 
 of conversion is designated a certain modification of the shade of any colour 
 produced on cloth by means of the intervention of some chemical agent. 
 This modification may be total or only partial, that is to say, brought on over 
 the entire coloured surface, or only in certain portions thereof, as limited by 
 the engraving roller. In order to illustrate this process the following par- 
 ticulars may serve : — 1. Some stripes or any other design is printed on in 
 acetate of alumina prepared for rose-red and mixed with nitrate of alumina. 
 If after drying there is next printed on a finer design with acetate of soda, this 
 substance wherever it comes into contact with the mordant first applied will 
 cause double decomposition to take place between the nitrate of alumina and 
 the last-named salt, and the result of this decomposition will be to give 
 increased strength to those portions of the mordant where such contact with 
 the acetate took place. Consequently the effect after dyeing will be the pro- 
 duction of a double rose-red. Similar effects can be obtained with the iron 
 mordants, and in that way double purples are produced. 2. Intersecting 
 stripes of purple or red will at the points of intersection have a deeper colour 
 by a similar application suitably executed. 3. Rose-red and purple may be 
 modified by the addition of catechu to the mordants, and afterwards a design 
 in bichromate of potassa may be printed on. Wherever this latter material 
 comes in contact with the previously applied mordants the oxidation of the 
 catechu will cause it to develop its peculiar brown colour, but over the rest of 
 the pattern it will disappear by means of washing immediately after the 
 application of the bichromate, so that on leaving the dye-beck the madder 
 colours will have only become developed just as if the catechu had not been 
 added to the mordant. 4. A mordant for good red is printed on, dyed, and 
 cleared, and next upon some portions of the same fabric a solution of oxalic 
 acid is printed on, the cloth is next steamed, and by this means the action of 
 the oxalic acid is brought into full force, and wherever it has been applied 
 the red colour is converted into rose-red. 5. By crossing stripes of a red 
 madder-dyed and cleared pattern by means of iron buff stripes, we shall have 
 three different shades of colour, viz. — A, red not acted upon ; B, buff upon a 
 white ground ; and C, the shade of colour due to the superposition of red and 
 buff. If there be next applied to this a pattern or impression of oxalic acid, 
 and the fabric afterwards steamed, the effect will be as follows : — The buff 
 will have been destroyed upon the white as far as the acid came into contact 
 therewith ; where the red, the buff, and acid meet violet will appear, from 
 which it may be inferred that the acid dissolves the alumina in preference to 
 the iron, and consequently gives rise to the formation of a lake having that 
 oxide as base. 6. Fine red stripes are first dyed by means of madder to 
 which nut-galls have been added, the tannin thereof fixed to the mordant 
 and which has resisted the clearing operations is invisible, the only effect 
 being that it slightly alters the peculiar beauty of the red ; but if after the 
 

 320 
 
 DYEING AND CALICO PRINTING. 
 
 clearing there are printed on this cloth stripes of buff (an iron mordant), a 
 black will appear on those stripes which are touched by the buff, while that 
 colour is not altered on the white portions. This proves that during the 
 dyeing process the tannin has only become fixed on those portions of the 
 cloth which are mordanted with alumina. A similar effect may be obtained 
 by substituting for nut-galls any other astringent, as, for instance, quercitron 
 or sumach. 7. Cloth uniformly dyed with Turkey-red is in some parts covered 
 with a thin paste containing tartaric acid and an iron salt. After drying 
 the cloth so prepared is immersed in a bath containing a solution of bleaching- 
 powder. This substance does not aft upon the Turkey-red dyed portion at 
 all, but the portions where the acid is printed are discharged, while at the 
 same time on these spots the iron is deposited, hydrated oxide being pre- 
 cipitated on the fibre. If the cloth is next, after previous washing, placed in 
 a somewhat acidulated solution of ferrocyanide of potassium, prussian blue 
 is produced upon the portions of the cloth where the red was discharged. 
 8. M. Carlos Kcechlin has published* the following interesting effect of con- 
 version operated upon a madder-dyed cloth: — 
 
 M. Persoz first observed that madder purple when treated with hydrochloric 
 acid is turned to an orange -yellow : if cloth so treated is next placed in a milk of 
 lime bath it becomes a beautiful bluish-purple, exhibiting great brilliancy. When 
 garancin-dyed purples are similarly treated there is only an amaranth colour 
 produced. This difference as regards the garancin is simply due to the 
 absence of lime from the purple-lake which garancin yields on cloth ; for if 
 there is added to the beck containing the garancin an excess of lime, so as to 
 produce a colour which resists strong soaping, the treatment with acid, and 
 subsequently with milk of lime, will have the same effect as on madder. 
 
 When a pattern dyed purple with madder or fleur de garance is immersed 
 in sulphuric acid, sp. gr. ni6, and next washed in water, and afterwards 
 immersed in a solution of aluminate of soda without excess of alkali (the 
 aluminate made from Bauxite), the pattern will become instantaneously red, 
 and the quantity of alumina which becomes fixed is in the direct proportion to 
 the strength of the iron mordant originally printed on the cloth, and having 
 served to produce the purple pattern. It therefore appears that the acid 
 (sulphuric just named) discharges the iron of the mordant, leaving the colour 
 untouched, and the latter — as soon as brought in contact with the aluminate 
 of soda — attracts alumina therefrom, combining with it instead of with the 
 iron which had been taken from it. The reds so obtained may be soaped, but 
 do not resist this operation so well as do the reds obtained by ordinary 
 methods. 
 
 As regards the opinion of M. C. Kcechlin upon the action of the lime for 
 fixing the purples, M. Mathieu-Plessy observes that the alcoholic extracts of 
 fleur de garance and garancin, neither of which contain any lime, yield in 
 dyeing — distilled water being used — very fast purples, which, if treated as 
 above described with hydrochloric acid, behave exactly as madder-dyed purples. 
 This fact proves that, as regards the cause of the want of fastness of garancin- 
 dyed purples, there is some unknown circumstance, and that it is not solely 
 due to the absence of lime. 
 
 * "Note sur la Teinture par Substitution" (Bulletin de la Societe Industrielle de Mul- 
 house, vol. xxviii., p. 119). 
 
TURKEY-RED. 
 
 321 
 
 We have now to consider the Turkey-red, as it is usually called, because, 
 as we shall presently see, this mode of madder-dyeing was introduced 
 into Europe from the East. Turkey-red is highly important, as much for the 
 various substances which concur in producing it as for its peculiar beauty, 
 intensity, and permanency. As far as the history of this branch of dyeing is 
 concerned we briefly note the following : — Undoubtedly this peculiar mode of 
 applying madder to cloth is of Indian origin, where, according to the account of 
 M. Le Goux de Plain, the cloth intended to be dyed is first steeped and padded 
 about in buffalo's or sheep's milk, and next exposed to the sun. From India 
 the art of preparing the cloth as required for this dye came over to the Levant, 
 and was introduced into France in the eighteenth century by some Greeks. 
 
 Before entering into the full details of Turkey-red dyeing, and discussing 
 the various points specifically, it will be advisable to give a concise preli- 
 minary sketch as follows : — This process consists in the application of the four 
 undermentioned operations : (a), mordanting of the tissues with oil ; (b), the 
 application of tannin (alum) ; (c), the dyeing in madder, or also in garancin ; 
 (d), the clearing and brightening. The first operation is performed on the 
 goods, which have been previously well bleached and bottomed, by liming and 
 bowking : they are immersed in a mixture of a peculiarly sour olive-oil (huile 
 toumantc), pearl-ash, sheep's dung, and water. On being removed from this 
 mixture they are slightly rinsed in water, and next brought over into a fresh 
 mixture of the oil, pearl-ash, and water. After being well worked about in this 
 liquid they are exposed to air, spread out on grass-plots, and placed as if for 
 the purpose of bleaching if the weather be warm, but in winter stove-heated 
 rooms are resorted to. This operation of oiling is repeated, in some instances 
 even seven or eight times. The excess of oil, or that at least which has 
 not changed its character by oxidation and alkali, is removed by steeping and 
 washing. The next process is the galling, as it is technically termed, and 
 this is sometimes done separately, at other times also combined with the appli- 
 cation of alum, but so that the immersion of the pieces in decoctions of 
 materials containing tannin is effected first, and followed by the steeping of 
 the goods in an aluminous mordant. The materials employed as astringents 
 are nut-galls and sumach, which are applied as infusion deco&ions, with which 
 the pieces are padded. After having been dried, the goods are padded in a 
 solution of alum previously neutralised with carbonate of soda ; dried and 
 alumed a second time, and next aged for some days ; they are then fixed, by 
 passing in warm water containing ground chalk. When washed out of this 
 the goods are ready for dyeing in madder or garancin. On leaving the dye- 
 beck the goods, which are of a very heavy brownish-red, are brightened by 
 two or three soapings, or a passage through acid. 
 
 Resuming briefly this important subject, we may state that the bleached 
 tissues, or yarn (animal fibres, however, wool and silk, are never so treated) 
 are first soaked in what is commonly, in this country, called Gallipoli* oil, 
 of a peculiar quality, because the oil to be suitable for this use must, when 
 mixed with a small quantity of an alkaline carbonate, form a white emulsion, 
 and this is due — as we know from M. Pelouze's researches— to a ferment which 
 the oil, when liberated from the berry, carries with it, and which resolves it 
 
 * Gallipoli is the name of an Italian sea-port town, whence olive oil is largely exported : the 
 oil here alluded to is, however, an inferior kind, at least as far as its consumption for food 
 is concerned. 
 
 Y 
 

 
 BB 
 
 322 DYEING AND CALICO PRINTING. 
 
 into its component parts, viz., glycerin and fatty acids. The oil so modified 
 is adapted for Turkey-red dyeing. The textile fabrics saturated with these 
 acids are dipped in a solution of carbonate of soda,* and then exposed to 
 the action of the air, or air and steam, in a warm room : after this treatment 
 has been repeated a sufficient number of times the goods are passed through 
 a solution of nut-galls, then into a solution of a salt of alumina, and next 
 through warm chalk water. They are next washed, dyed by being boiled for 
 two or three hours in a bath to which madder-root or garancin has been added ; 
 lastly, the brilliancy of the colour is brought up by boiling in a strong soap 
 solution. Up to this day no thoroughly satisfactory explanation of the 
 real effect of the application of the oil in this process has been given, and 
 since it is an acknowledged fact that no Turkey-red can be obtained without 
 this application, we do not enter into any speculative discussions on this 
 subject, but simply give a detailed account of the operations just indicated, 
 with the observation that the processes are varied by different manufac- 
 turers according to their own experience. The goods, first properly bleached, 
 are padded in an emulsion made of the oil t and of an alkaline carbonate : the 
 olive-oil applied for this purpose has the characteristic property of readily 
 yielding a permanent emulsion when shaken up with an alkali. The mode of 
 testing the oils for this purpose consists in beating up 1 part of oil with from 
 36 to 40 parts of soda-lye containing about \ per cent of dry caustic soda. 
 If, after standing for some five or six hours, the mixture is found to be homo- 
 geneous, without any sign of a separation of the oil, it is admitted as of 
 fit quality. This Gallipoli oil is prepared from rather unripe olives, which are 
 steeped for some time in boiling water before being pressed. This treatment 
 causes the oil to contain a large proportion of extractive matter. 
 
 In France the best and ripest olives yield, as is well known, a small quantity 
 of oil spontaneously without pressure ; gentle pressure is next applied, and 
 lastly the pressed cake is placed in boiling water for a couple of hours, and 
 on being then pressed again, yields what is locally known as huile d'cnfcr 
 used for soap-making, and burning in lamps, and is very suitable for the purpose 
 of mordanting Turkey-reds. 
 
 According to M. Persoz any oil may be rendered easily emulsive (touriiante) 
 by beating up therewith two yolks of egg per litre. This statement does not 
 hold good for the drying oils, since this was purposely tried several years ago 
 by the elder M. Previnaire, at Ghent, who found that neither linseed, hemp- 
 seed, nor poppy-oil would answer the purpose, not even when previously beaten 
 up with yolk of eggs. This is confirmed by Professor Mulder's extensive 
 researches on drying oils, which, according to him, belong rather to the class 
 of substances producing caoutchouc than to the true fatty oils. According 
 to the experiments made by M. E. Schwartz the action of the alkalies, prefer- 
 ably carbonates, or even bicarbonates, is not simply to form an emulsion, but 
 also to predispose the oil for the peculiar changes it has to undergo afterwards. 
 It is considered by many manufacturers necessary to add sheep- or cow-dung 
 
 * The reader will no doubt be struck with discrepancies in the details of the process as 
 here laid down, but there is scarcely any dyeing operation in which so many variations occur, 
 all, however, tending to one general result. 
 
 t In Europe generally an inferior kind of olive-oil is used, but in the East (India, Persia), 
 where the natives still produce the finest and fastest reds, many kinds of oil are used — for in- 
 stance, fish-oil, lard, and other fatty matters — very successfully. 
 
TURKEY-RED. 
 
 323 
 
 to the mixture of oil and alkali, it being thought that these materials animalise 
 the cloth ; but it is more probable that since these materials contain principles 
 of bile in a high state of activity they exercise some influence tending 
 to a peculiar decomposition of the oil, while, moreover, the albuminous 
 compounds present aid the formation of the emulsion. Be this as it may, 
 the cloth — after having been uniformly worked about and padded in the 
 mixture, as described — is dried in a stove-warmed room, and next placed 
 on the grass, or, if the weather be hot and fine, the cloth is at once dried in 
 the sun. The joint action of a suitable temperature with air, light, moisture, 
 and the alkaline carbonates, brings about a transformation of the oil in a 
 peculiar manner, the true nature of which is unknown to us. Instead there- 
 fore of entering into hypothetical discussions on this subject, we prefer to lay 
 before our readers the results of the experimental researches made by some 
 chemists, among whom is M. Weissgerber, assistant to the late M. Persoz. 
 He took oiled and cleansed cloth, and exhausted it by means of aceton. 
 After repeatedly applying this fluid to the cloth, he observed that it lost more 
 and more the property of attracting the colouring matter of madder from the 
 dye-beck. On evaporating the acetonic solution in the water-bath he obtained 
 a viscous liquid residue, which was found to consist of two substances, — one 
 a solid body, the other a liquid. This latter did not, on being saponified, 
 yield even the slightest trace of glycerin, and when the original liquid was 
 applied to cloth it dyed up beautifully in the beck with madder. 
 
 Dr. Schiitzenberger has recorded the following experiments : — He took cloth 
 dyed and cleared for Turkey-red, and treated it at a gentle heat with very strong 
 alcohol acidified with sulphuric acid. The liquid thus obtained was saturated 
 with ammonia, the alum precipitate separated by filtration, the solution next 
 concentrated by evaporation and precipitated by the addition of water. The 
 substances thus thrown down were removed by filtration, and, after washing 
 and drying, were exhausted by means of sulphide of carbon, which dissolves 
 only fatty matters, leaving a residue of pure alizarin. On removing the sul- 
 phide of carbon by evaporation there remained an oily, slightly reddish 
 residue, a portion of which, when brought into contact with baryta-water, 
 yielded at once, even in the cold, a barytic soap. Hence it is evident that the 
 fluid in question contains a fatty acid in a free state. Another portion of this 
 fluid was found to saponify very readily with hydrate of baryta, with the aid 
 of heat, but there was left a non-saponifiable material, in all probability the 
 same substance found by M. Weissgerber. The barytic soaps were readily 
 soluble in alcohol, and separated therefrom in acicular crystals. 
 
 Since it is a well-known fact that sulpholeic acid, as obtained by the saponi- 
 fication of oils with sulphuric acid, when decomposed by means of water, 
 yields a substance endowed with the property of rendering madder colours 
 extraordinarily fast when mixed with mordants, it is very probable that the 
 oleine of the Gallipoli acts essentially in producing such an organic mordant. 
 The modified Gallipoli oil acts therefore — (1), as a mordant, because, according 
 to the researches of Prof. Chevreul, some Turkey-reds contain only a very 
 small proportion of alumina; (2), as fastener of the red lake ; (3), it has been 
 proved by Kuhlmann that it has the property of precipitating and energetically 
 retaining several metallic oxides, as, e.g., oxide of iron. This may be readily 
 proved by simply dipping previously oiled cloth into a solution of a per-salt of 
 iron, to obtain, on dyeing it afterwards with madder, a beautiful purple colour. . 
 
 Y2 
 
BH I ■:■■'■•--.■•■■ ■ .-■■ ■: ■■■■:..■ M| HUH 
 
 324 DYEING AND CALICO PRINTING. 
 
 That the peculiar action of the modified fatty substance is not simply confined 
 to the red, but is equally strong for purples, is proved by the fact that the 
 Messrs. Weber, at Mulhouse, used to manufacture a cloth, previously oiled and 
 next mordanted, for purples, which was so fast that it could be plunged into 
 rather concentrated hydrochloric acid without affecting the shade in the least. 
 According to M. Persoz the most beautiful Turkey-red cloth exhibits, on being 
 torn up, a nearly white section, — that is to say, the dye is rather superficial. 
 His opinion is that the physical properties of the oil play some part in the 
 process, inasmuch as it serves to envelope the particles of the lake, and to 
 prevent the destructive action of externally applied agents. Resuming, in a 
 few words, what may be considered experimentally proved concerning the 
 action of the emulsified oil, it acts chemico-physically partly as a mordant, in 
 as real a sense as alum: partly as a varnish, protecting as well as brightening 
 the colour, the latter property being due to the peculiar transparency given to 
 the cloth by the immersion in the emulsified oil. 
 
 We now return to the practical operations, and state first that this treatment 
 of the cloth in the emulsified oil-bath, drying, and exposure to air, has to be 
 repeated several times : a small piece may be taken for trying whether the 
 oiling is sufficiently effected, by first working it about in a solution of carbonate 
 of soda, and next immersing it in a bath containing a sumach infusion. If, 
 on being removed therefrom and rinsed in cold water, the swatch assumes, 
 when immersed in a solution of acetate of alumina, a deep yellowish tinge 
 (isabella colour), the oiling is quite what it should be. After the oiling 
 operation follows the removal of excess of grease, by means of a solution of 
 carbonate of soda in water, whereby the unmodified oil is removed, as well as 
 any excess of the modified portion which adheres only loosely to the fibre. 
 The liquid remaining from this operation is usefully employed instead of 
 the first oiling, and is therefore preserved and technically known by the name 
 of old white bath. The operation which follows is that of applying the 
 aluminous mordant, sometimes preceded by a bath containing an infusion of 
 nut-galls and sumach ; sometimes, again, the aluminous mordant and the 
 astringent materials are mixed ; but in all cases the mordanted cloth is dried, 
 and after that passed through a tepid mixture of finely-ground chalk and 
 water, in order thereby to aid the precipitation and fixation of the alumina. 
 After rinsing and drying the cloth is ready for the dye-beck, wherein either 
 madder or fieur de garance is used. In the former case chalk and bullock's 
 blood, sumach and glue, are often added ; but, the mineral matter excepted, 
 there seems to be little use for these admixtures. Very frequently the dyeing 
 operation is repeated twice, or even three times, with the understanding, how- 
 ever, that it is in each case first followed by a thorough clearing, next a fresh 
 mordanting, and then again dyeing. 
 
 The clearing operation consists in boiling the dyed goods, under pressure, 
 with soap and carbonate of potassa first ; and next by a twice repeated boiling 
 in solution of tin-salt and soap, or also, in addition thereto, carbonate of 
 potassa. The chief action of these substances is, in this instance, confined 
 to the elimination of the yellow and other colouring matters present in the 
 cloth, which previous to clearing always presents a deep brownish brick-red, 
 and lacks the peculiar beauty and the bleuctt€ appearance of genuine Turkey- 
 red. The tin-salt acts undoubtedly, also, by causing the combination of a 
 
TURKEY-RED. 
 
 325 
 
 small quantity of oxide of tin with the colouring matter, and thereby giving to 
 the red a fiery-scarlet hue, which is one of the great characteristics of Turkey- 
 reds dyed and well got up. 
 
 Among the modifications introduced in the above operations we briefly 
 quote the following, reminding our readers, at the same time, that almost all 
 dyers of Turkey-red follow processes of their own invention, and keep these 
 modes of procedure strictly secret : — M. Haussmann pads the cloth in a mix- 
 ture of olive oil and aluminate of soda, the effect of which is the simultaneity 
 of the oiling and mordanting operations. M. Gastard applies — after every 
 oiling, drying, and airing operation of the cloth — a nitric acid bath of 1/007 
 sp. gr. (exactly 1 per cent of the most concentrated acid), followed by drying 
 in the open air : he appears to have been induced to this proceeding by the 
 idea of promoting the oxidation of the oil. M. Steiner prepares the cloth, — 
 that is to say, causes it first to be padded in a solution of an alkaline car- 
 bonate ; next it is put through the oil-bath, and thence it is passed between 
 rollers along with two other pieces similarly prepared. On leaving the rollers 
 the cloth is transferred to a stove-heated ageing-room, where it is placed in 
 the best possible conditions for the rapid completion of the peculiar conversion 
 of the oil without the necessity of repeating the operation. Very beautiful 
 rose-red colours are obtained by placing previously oiled and feebly mordanted 
 cloths along with Turkey-red pieces in the boiler, wherein the latter are placed 
 for clearing under pressure. The colouring matter detached during that ope- 
 ration is sufficient to impart to the cloth, prepared as just mentioned, an 
 excellent and fast shade. For purples it is required to use sheep-dung along 
 with the oil-bath, and to employ nitro-sulphate of iron as a mordant. According 
 to Kcechlin the application of nut-galls or sumach is not required if the alum is 
 first neutralised. The following may serve as a kind of diagram for the eluci- 
 dation of this operation : — For 1000 kilos, of cotton* are required from 585 to 
 650 kilos, of the peculiar olive oil, 1500 litres of water, and from 9 to 10 kilos. 
 of carbonate of potassa : after the immersion and working about in the bath 
 the fabric is placed on a heap, in a cool place, t for ten or twelve hours, and 
 next hung up to dry in a room heated to 6o°. These operations are repeated 
 from seven to eight times ; next follows the washing in an aqueous solution of 
 carbonate of potassa, consisting in a steeping of the goods during a period of 
 twenty-four hours, and twice repeated in a solution of carbonate of potassa, 
 sp. gr. i'OT4 (containing about 2 per cent of that salt at 15 C.) ; wringing out, 
 rinsing in cold water, and next padding, at 70 , in a bath made up of 300 litres 
 of a decoction of nut-galls (10 kilos.) and 16 kilos, of alum, quantities which 
 suffice for 500 kilos, of cotton ; drying in the stove-heated room at 45 , being 
 hung up there for two days. 
 
 Chalk Bath. — The dyeing is performed with 10 pieces at a time, with from 
 3 to 4/5 kilos, of madder for each piece ; water, from 1500 to 1800 litres : the 
 bath is gradually but regularly heated, during 2 J hours, up to the boiling-point, 
 at which it is maintained for a quarter of an hour. After this follows a second 
 galling and mordanting, in the same manner just described, and after that 
 again a dye-beck precisely similar to the first ; followed by the first clearing, 
 in a boiler under pressure, during eight hours, with 6 kilos, of soap and 1*5 
 
 * This may be yarn, since it is very frequently dyed Turkey-red. 
 
 * We may briefly point out the peculiar liability o( Turkey-reds to spontaneous combustion. 
 
326 
 
 DYEING AND CALICO PRINTING. 
 
 Madder. 
 
 kilos, of carbonate of potassa ; second clearing, under pressure, with 6*5 kilos, 
 of soap and 0*375 g rm ' tin-salt ; next, third clearing the same as second ; 
 and next a bran-bath. The reader will readily observe that in the process as 
 here described the oiled goods are not exposed to the bleach-field, and it is 
 therefore apparent that the action of light can be replaced by that of heat. 
 The oiled goods are sometimes heaped together in a room heated to 35 , care 
 being taken to move the goods about so as to prevent their spontaneous com- 
 bustion by a too adtive oxidation of the oil. 
 
 Turkey-reds are very readily recognised by the peculiar fiery and deep tone 
 of the colour, but if there is any doubt on this subject it is only necessary to 
 immerse the piece to be tested, for a few moments, in a boiling solution of 
 
 Artificial Alizarin. 
 
ANTHRAPURPURIN. 327 
 
 hypochlorite of soda, sp. gr. 1*036. No other red-dyed fabric will stand this 
 treatment, whereas the Turkey-red becomes more fiery and but very slightly 
 altered in depth. Add to this, that it is not affected in the least by being im- 
 mersed in dilute hydrochloric acid and in a solution of oxalic acid. The 
 pattern inserted at the top of the opposite page, for which we are indebted to 
 Messrs. Steiner, Church, near Accrington, will give the reader an idea of 
 what this dye is like when properly executed. It is dyed with madder root, 
 not with garancin or any other special preparation. 
 
 For comparison we also annex a specimen of Turkey-red dyed with Messrs. 
 Perkin and Sons' artificial alizarin, which we owe to the courtesy of Mr. W. H. 
 Perkin. 
 
 This may also be the proper place to mention a new colour made known 
 after the section on the coal-tar derivatives was completed. We refer to 
 anthrapurpurin — the latest discovery of Mr. W. H. Perkin. This substance, 
 which is already largely used by calico printers, has nearly the same affinity for 
 mordants as alizarin, and the colours which it produces are analogous. With 
 alumina it yields a red, and with iron mordants purple and black. In the tone 
 of the colours thus produced there is a considerable difference, the reds being 
 purer and less blue than those obtained from alizarin, while the purples are 
 bluer, and the blacks more intense. In fastness against soap and light the 
 colours are quite equal to those from alizarin. Its composition is — 
 
 Carbon 65*62 
 
 Hydrogen 3*12 
 
 Oxygen 3126 
 
 IOO'OO 
 
 corresponding to the formula Ci 4 Hs0 5 . Anthrapurpurin, when heated, fuses, 
 and then gives off orange vapours, which condense in yellowish-red leaflets 
 or needles, though the largest part of the substance is carbonised. It is 
 sparingly soluble in alcohol and ether, but rather more freely in glacial acetic 
 acid. In water it is very slightly soluble. If heated along with zinc-powder 
 it yields a hydrocarbon which agrees in its properties with ordinary anthracen. 
 If an ammoniacal solution of anthrapurpurin is heated to ioo°, in a sealed 
 tube, for some hours, its colour changes from purple to indigo-blue. This 
 solution, when acidified with hydrochloric acid, deposits a new product as a 
 dark purple precipitate, soluble in ammonia and in carbonate of soda with a 
 blue colour, but in caustic alkalies with a reddish purple. It dyes alumina 
 mordants purple, and weak iron mordants an indigo-blue. It is probably 
 isomeric with Stenhouse's purpuramide. Solutions of anthrapurpurin in 
 caustic potash always show the absorption-bands in the same region of the 
 spectrum, as do alkaline solutions of alizarin, but are less intense. The 
 ammoniacal solution does not appear to give bands, nor does the ethereal 
 solution of the colouring matter. In the latter case the violet is almost 
 entirely absorbed. 
 
 A curious fad, and which may serve to illustrate the action of oils as mor- 
 dants, is related in a Dutch work, very little known, published a few years 
 since, on Borneo and adjacent islands. The authors, a party of an exploring 
 expedition, found that whereas the very wild and barbarous tribes of a portion 
 of the country in question were utterly ignorant of any art approaching to 
 
■MM TnmfrMmwnrwwrmT TWrwwrTSn 
 
 1— — — —— — — W MBBBW^ 
 
 328 
 
 DYEING AND CALICO PRINTING. 
 
 the slightest degree even the knowledge of the Malays, concerning dyes 
 and dyeing fabrics, they (the Dyaks of Borneo) were in possession of some 
 very fast-dyed coarse fabrics, which were obtained by steeping the fibrous 
 materials for some time in oil or fat, wringing out of the excess of 
 these substances, and treading the greasy fabric about in the juice of some 
 plants, or rather squeezing up with the feet the young leaves and twigs so 
 as to obtain juice ; after this another immersion in oil was resorted to, and 
 again the squeezing operation just referred to ; and lastly, after exposure to 
 air, the fabrics were dyed a deep brownish-yellow by boiling them along with 
 some vegetable matter, which, on investigation by the explorers (among whom 
 were two physicians and a scientific chemist), proved to be simply an astrin- 
 gent which did not dye, but only slightly — yet not permanently — stained cotton 
 or other fabrics net previously oiled. There is no doubt that the oil acts as a 
 mordant in this case, and the treatment of treading the previously oiled cloth 
 about in a vegetable readily-fermentable mass is, in all probability, done to 
 cause the oil to undergo a peculiar change : the authors observe that, just as 
 in Java, the inhabitants of the Indian Archipelago have in earlier times 
 enjoyed a high degree of civilisation ; they (the explorers) could not find out 
 whether at any former time there had been intercourse between the Chinese 
 and the aborigines alluded to ; the Celestials are well enough acquainted with 
 dyeing, and also that of producing a fast red, by means of chayaver. 
 
 We have now to say a few words about some products of the family of the 
 Rubiacea, not used in Europe, but in some parts of Asia, as dye materials 
 instead of madder, which does not thrive well in too hot climates. Some 
 experiments for the cultivation of madder were made at the very extensive 
 botanical gardens at Buitenhorg (Java), but it was^ found that unless the culti- 
 vation was proceeded with at a great elevation above sea-level, quite upon the 
 high mountains, where European vegetables are purposely grown for the use 
 of the Dutch colonists, madder did not thrive, — that is to say, the roots, 
 although perfectly developed, did not yield any dye material worth mentioning, 
 and the plant itself entirely degenerated. This has also been experienced at 
 Pondicherry, and other parts of the mainland of India where the cultivation of 
 madder was tried. We owe to the researches of Messrs. E. Schwartz and 
 D. Kcechlin some knowledge about the tinctorial produces belonging to the 
 RubiacccE grown in India (Southern Asia), samples of which were brought to 
 Europe by M. Gonfreville.* Among these, in the first place, is the chayaver, 
 a plant cultivated on the coast of Malabar and Coromandel, where the root is 
 employed to impart a red dye tn previously oiled cloth. This plant prefers a 
 sandy soil ; the root is very much like twine, exhibiting a greyish external 
 colour, while its thickness does not exceed a millimetre. Internally its colour 
 is bright yellow. This material is very tough, and far less easily pulverised 
 than madder roots. The chayaver is a material very generally used as a dye 
 throughout India; the chemical history and immediate analysis of this root 
 are almost unknown. Dr. Schutzenberger obtained a small sample, and by 
 testing this he found that the chayaver contains chlorogenin and alizarin, — 
 that its colouring matter is readily exhausted by means of alcohol, owing to 
 the natural acidity of the root, which does not contain lime salts. Messrs. 
 Schwartz and Kcechlin state, about this root, that they found it analogous to 
 
 See "Bulletin de la Societe Industriellc," vol. v., p. 301, and following. 
 
SUBSTITUTES FOR MADDER. 
 
 329 
 
 Avignon madder as regards its qualities as a dye-stuff, but being acid, as is the 
 case with all the Indian Rubiacece in a very high degree, it requires the 
 addition of chalk in the dye-beck; the colours produced upon fabrics are in 
 every respect the same as those produced by madder, and are also the same 
 with the same mordants. The chayaver, however, hardly contains the fourth 
 part of colouring matter found in madder, taking, of course, equal weights of 
 each. 
 
 Mungeet, or Ritbia mungista, is characterised by the peculiarity that the 
 stem contains more colouring matter than the root. In a dried state it is 
 almost as rich in colouring matter as good Avignon madder, but it contains 
 much acid and a great deal of yellow colouring matter ; it does not yield fast 
 shades at all, and, even with the treatment for Turkey-red, the cleared red — 
 at first bright and beautiful — is rapidly destroyed by sunlight. Dr. Stenhouse* 
 has made some researches on this mungeet which prove that it does not con- 
 tain alizarin or purpurin, but a peculiar colouring matter which this chemist 
 has called mungistin. To obtain this, the previously pulverised root is 
 treated with a boiling solution of alum (500 grms. of mungeet root, 1 kilo, of 
 alum, and 8 kilos, of water) ; the liquid, having been filtered, is boiled, when 
 there is thrown down a bright red precipitate, which is collected on a filter, 
 washed, and dried. The dried material is treated with sulphide of carbon, 
 which dissolves the colouring matter, while a resinous substance is left. The 
 sulphide of carbon solution yields, on evaporation, a bright red residue, con- 
 sisting of mungistin and purpurin. When this is acted upon by boiling water 
 acidified with acetic acid, the purpurin is left undissolved, while the mungistin 
 is taken up, yielding a yellow solution as long as the fluid is hot, but on 
 cooling the mungistin is thrown down. This precipitate is purified by means 
 of boiling alcohol, from which the mungistin crystallises out on cooling. 
 This substance is sparingly soluble in cold, but more freely in hot, water; 
 slightly soluble in cold, but readily so in boiling, alcohol. Mungistin is fusible 
 by heat, and crystallises again on cooling : it dissolves in aqueous solutions of 
 the carbonates of potassa and soda, and the caustic alkalies and ammonia, 
 yielding bright red solutions. With baryta water it yields a yellow precipitate, 
 and hydrate of alumina forms with it a bright orange lake. Mungistin is 
 soluble in strong sulphuric acid ; its formula is, according to Dr. Stenhouse, 
 C8H6O3 : concentrated nitric acid converts mungistin into phthalic and oxalic 
 acids ; highly concentrated ammonia converts this body into a brownish humus- 
 like substance. 
 
 Under the name of nona is designated the root of a rubiaceous tree belonging 
 to a species of guilandina. This root has great similarity with madder root, but 
 is more difficultly pulverised, and contains a large quantity of yellow colouring 
 matter and much acid, so that previous to being fit for dyeing it should be 
 washed with water, and in order to render the colours fast carbonate of soda 
 is required to be added to the dye-beck. According to the experiments made 
 by Messrs. Schwartz and Kcechlin, the nona root should be first ground to a 
 fine powder, next washed with fifty times its weight of pure cold water, after 
 which it is fit for the dye-beck, with the addition of one-fifth of its weight of 
 carbonate of soda. The initial temperature should be about 39 , and gradually 
 be raised to boiling : in this manner previously oiled and mordanted cloth 
 
 * See " Annalen der Chemie unci Pharmacie,'' vol. exxx., p. 325. 
 
-••"-vj? 
 
 
 330 
 
 DYEING AND CALICO PRINTING. 
 
 cleared after dyeing, as described for Turkey-reds, becomes beautifully 
 scarlet, very nearly equal to good Turkey-red. Cloth not oiled, simply mor- 
 danted in the ordinary manner for red madder shades, is dyed, by the aid cf 
 nona, somewhat like madder but more yellowish, and this tinge remains after 
 clearing. 
 
 The dye material known as ouongkondou contains, according to the 
 researches of the chemists just named, about from one-third to one-half of the 
 quantity of red colouring matter found in good Avignon madder, but the 
 ouongkondou, although less acid than mungeet, yet requires in dyeing an 
 addition of 3 per cent of carbonate of soda. The shades obtained are less 
 fast and less beautiful than those yielded by nona. 
 
 Hachrout is, if not identically the same as nona, — which may be the case 
 considering the large number of dialects and different languages spoken in 
 India, — at least so very similar thereto that Messrs. Kcechlin and Schwartz 
 detected no difference. 
 
 The horticultural experiments made with these plants in Java, by the care 
 of the directeur des cultures in that island, prove that, with suitable nursing 
 and careful selection of manures and soils, the plants are very greatly im- 
 proved in their qualities as dye materials. The Javanese have discontinued 
 the use of these materials, because the European trade imports to them far 
 better goods and far faster dyed fabrics than they could manufacture, and at 
 far less cost. 
 
 The scientific researches on these substances are very incomplete ; there 
 are in the India Museum, formerly open to the public, when at old Fyfe 
 House, now at the India Office, a very large and interesting number of 
 samples of various dye materials used all over India by the natives. It would 
 add much to our knowledge on this subject were some scientific chemist, who 
 has time and leisure, supplied with a sufficient quantity of all or some of 
 them to complete an investigation into their properties. 
 
(330 
 
 CHAPTER IV. 
 
 RED WOODS. 
 A. Open or Soluble Class. 
 OEVERAL woods are known, all characterised by the feature that they im- 
 v ^ part to tissues mordanted with alumina or tin a fugitive red colour. The 
 trees from which they are obtained belong to the natural order of LeguminoscF, 
 and are natives of warm climates, especially Central and South America, the 
 Antilles, and India. These woods are met with in commerce in the shape of 
 fagots, of irregular blocks, and billets. In physical structure these woods are 
 hard and compact ; the colour is internally bright yellow, but the portions ex- 
 posed to air are brown. They are devoid of smell ; their taste is sweetish bitter 
 or astringent, and they tinge the saliva red. In India some of these woods 
 were employed for dyeing purposes long before the discovery of America (1492), 
 and some of them even appear to have been known and used in Europe before 
 that epoch. The following varieties of " open " red woods are used to a 
 greater or less extent : — 
 
 1. Fernambuco* wood, the best variety and the richest in tinctorial matter, 
 is imported from Paraiba. It is the product of the Ccesalpinia crista, a tree 
 abundantly found in Jamaica as well as in Brazil. It is imported in billets, 
 varying in weight from 4 to 120 lbs. The wood is hard, heavy (the 
 sp. gr. of these woods being generally above that of water, and averaging 
 1*014), compact ; externally red; internally pale yellowish red when freshly cut, 
 but on exposure to air it becomes a deep brown-red. Its taste is sweetish, 
 and its odour faintly aromatic. It tinges water beautifully red. 
 
 2. Brazil wood, properly so-called, the product of the Ccesalpinia brasiliensis, 
 from the immense forests of that large country, is met with in trade in the 
 shape of large irregularly hewn blocks ; it is hard, compact, and, when freshly 
 cut, a brick-red, but becomes deeper brown on exposure to air. It is capable 
 of taking a polish. Its tinctorial value is about one-half less than that of 
 Fernambuco wood, but like most of these woods improves by age. It becomes 
 better even after having been cut down, provided it is not exposed to excessive 
 moisture. 
 
 3. St. Martha wood, produced by the Ccesalpinia cchinata, growing in the 
 native forests of St. Martha, or Sierra Nevada of Mexico. It is met with in 
 commerce in billets about 1 metre in length ; one end of these is commonly 
 cut off rounded, but the other end is sawn through square. These billets are 
 full of cracks, generally filled with splinters, and vary in weight from 20 to 
 40 lbs. Its physical properties are much the same as those of the kinds above 
 
 * Also written Pernambuco. 
 

 332 
 
 DYEING AND CALICO PRINTING. 
 
 mentioned. Its transverse section exhibits a starry form ; its tinctorial value 
 is less than that of genuine Fernambuco wood, but it is generally considered 
 the second best for dyeing purposes. 
 
 4. Nicaragua wood is probably the produce of the same tree as the last- 
 named species. It is named from that region of Central America where it 
 grows. 
 
 5. Sapon, or sappan, wood is the product of the C&salpinia sappan, a tree 
 growing over a considerable portion of the warmer regions of Asia. This 
 wood occurs in commerce in the form of billets, free from splinters, and ex- 
 hibiting a medullary cavity, sometimes filled with a reddish yellow pith, but 
 sometimes quite empty. The wood is very hard and compact, fine grained, 
 capable of a brilliant polish, while its colour is less deep than that of most 
 kinds of these woods. Two principal kinds are known, viz., that imported 
 from Siam, in pieces free from splinters, and of the thickness of a man's 
 arm, the colour being rather deep red internally; the other variety is known 
 as Bimas, and occurs in sticks of from 27 to 33 millimetres thickness ; in- 
 ternally its colour is yellowish, but where it has been exposed to the action 
 of the air it is rose-red. The so-called Lima wood of commerce is a variety 
 of sapan, and the dye-woods imported from Manilla and the other Philippine 
 Islands, from St. Martin aria 1 Padang (Sumatra), are inferior qualities of the 
 same. 
 
 6. Bahamas, or Jamaica wood is, according to some, the product of the 
 Ccesalpinia vcsicaria ; but, according to others, is yielded by a shrub belonging 
 to the genus Balsamodcndron. It is known in trade by various names according 
 to the place from which it is shipped, among which is Nickerie, Surinam, and 
 especially the Island of Jamaica. It is met with in the shape of sticks, free 
 from bark, and about 54 millimetres thickness, covered by whitish splinters. 
 Within its colour is red-brown with darker veins. It is the lowest in tinctorial 
 value of all these woods. 
 
 7. Californian wood, the product of a hitherto unspecified Ccesalpinia, found 
 in the Californian forests, is as yet only met with in trade in the shape of 
 irregularly-sized knotty pieces. It is exceedingly hard, its colours rather 
 dark yellow when freshly cut, becoming first brown on exposure to air, and, 
 lastly, violet-red. 
 
 8. Tierra Firma wood, the product also of an unspecified kind of Casalpinia, 
 growing in some of the forests of Venezuela and New Granada. It occurs in 
 the shape of hewn blocks, serving for stowage, and is very hard, knotty, and 
 compact, with longitudinal fibres. It is internally of a golden-yeliow, 
 exhibiting concentric circles of a yellowish red. 
 
 9. Bahia wood, so-called from being generally met with in the forests of 
 the Brazilian province of that name, occurs in large square billets. Its colour 
 is yellowish, but becomes darker on exposure to air. In tinctorial value it 
 holds about the middle place between the best Fernambuco and the inferior 
 varieties mentioned above. 
 
 The chemical history of these red woods is as yet in a very incomplete 
 state. Nothing is positively known about the foreign substances occurring 
 in the wood along with the colouring matter, and that substance itself has 
 been but incompletely studied. As far as the former are concerned, we may 
 reason by analogy and say that these woods contain saccharine matters, 
 
RED WOODS. 
 
 333 
 
 astringent principles, organic acids combined in various ways, resins, and 
 mineral salts.* Hitherto only one colouring matter has been found in these 
 woods, but the absence of others, however analogically probable, is not 
 formally demonstrated. The colouring material is totally soluble in water, and 
 can be extracted from the ligneous matter by repeated decoctions or infusion. 
 It exists in the wood in an almost colourless state, or at least its colour is 
 only a pale yellow, but on coming into contact with air this hue becomes 
 gradually darker, and at last red-brown. There appears to be slow oxidation 
 of colourable matter to form a real pigment. The aqueous decoctions of these 
 woods are yellow at first, and only assume a red by the action of air or the 
 addition of aerated water (that is, ordinary fresh water, which, not having been 
 boiled, contains air). This phenomenon, however, is somewhat dependent on 
 the variety of the wood, and also on the fact of its more or less immediate 
 use after being ground to powder. The colouring matter is supposed by 
 some to exist in these woods as a glucoside, since the decoction exerts very 
 little reducing action upon a cupro-potassic solution ; but when the decoction 
 has been heated for some time with either sulphuric or hydrochloric acids it 
 yields, on treatment with the cupro-potassic test, an abundant precipitate of 
 red oxide of copper. After the splitting-up of the glucoside has been 
 effected the colouring matter exhibits a tendency to crystallise, which it did 
 not previously possess. It is only required to treat the acidified decoction 
 while yet hot ( T J c th of acid is sufficient) with an alkaline salt, when, on 
 cooling the fluid, there will appear a more or less red-coloured crystalline 
 substance, its shade depending on the degree of oxidation it has undergone. 
 The addition of the alkaline salt has the effect of diminishing the solubility 
 of the colouring matter. There exists, therefore, in the decoctions of the woods 
 a colourable glucoside in a more or less advanced state of oxidation ; and, 
 moreover, a certain proportion of free colouring matter, which either pre- 
 exists as such in the wood, or is formed during the boiling with water by the 
 splitting-up of the glucoside. 
 
 The colourable glucoside, which is very abundantly present in freshly- 
 made decoctions of the wood, is not precipitated by neutral acetate of lead, 
 but is thrown drown by the subacetate. When a solution of the neutral 
 acetate is added to a decoction there is formed a bulky brick-red precipitate, 
 which contains, besides tannin and some foreign substances, chiefly bresi- 
 line and colouring matters already oxidised. The filtrate from this precipitate, 
 a faintly yellow liquid, dyes up shades of equal richness, but of far more beauty 
 than the original decoction. This liquid, moreover, yields, on being treated 
 with basic acetate of lead, an abundant lilac precipitate. Oxidation of the 
 colouring matter is a slow process in the first place, and requires especially 
 conditions which favour it; and among these ammoniacal vapours and the 
 faintest traces of potassa or soda are the chief agents. Decoctions of most 
 of these woods may be kept even in open vessels for several months 
 without any very prominent change being observable. The colour of the 
 liquid remains bright yellow, while the rasped wood becomes rapidly brown, 
 an effect, as regards the latter, due to the presence in the wood of substances 
 
 * Generally Bpeaking our knowledge about wood is very limited, and it is to be regretted 
 that the wares here named have not been more fully studied. They deserve it equally with 
 such kinds of wood as ebony and iron-wood, and many others, the products of warmer climes. 
 

 334 
 
 DYEING AND CALICO PRINTING. 
 
 which aid the oxidation by becoming altered somehow themselves. To a 
 .certain extent the wood, after having been rasped, gains in tinctorial value by 
 contact with air for some time, but it should not be exposed too long, and 
 certainly not be submitted to the direct action of the sun's rays, which will 
 soon cause the destruction of the pigment altogether. The decoction of the red 
 woods is also very sensitive to the action of reducing agents ; sulphuretted 
 hydrogen discolours this liquid, and when boiled even with TV \r V th °f sulphide 
 of sodium, the decoction only exhibits a reddish hue due to the influence of the 
 alkaline reaction of the salt, but this colouration disappears if the alkali is 
 neutralised by an acid. When a decoction so treated, and quite colourless, is 
 used for a dye-bath, it would at first appear to be worthless, but as the tempera- 
 ture rises the colour returns, and the dyeing operation goes on as well as with 
 the original decoction though attended with a great loss of colouring matter. 
 Acids have the effect of rendering the colour of the decoctions yellow, with a 
 more or less orange shade, which depends on the fact of the more or less oxidised 
 state of the wood used for the decoctions. After the lapse of some time decoctions 
 so treated deposit a crystalline substance, which is yellow in case the decoc- 
 tion was quite deoxidised, otherwise it exhibits a red colour. Excess of 
 hydrochloric acid added to the decoction turns them a bright rose-red, but 
 this hue disapears on the addition of water. Caustic and carbonated alkalies 
 turn the colour of the decoction to a carmine-red. When lime or even chalk 
 is added to a decoction of these woods the liquid becomes carmine-red 
 coloured: this base has a specific effect in promoting the oxidation of the 
 decoction. The liquid thus treated soon becomes covered with a black 
 pellicle, which'after a while sinks to the bottom of the liquid, and the for- 
 mation of another coating in its stead begins. Alum turns the decoction to a 
 red, but does not cause a precipitate ; if, however, so much of an alkaline 
 carbonate is added as to make the alum basic and a gentle heat is applied, a 
 red-coloured lake is precipitated. Acetate of alumina heated with the decoction 
 behaves in the same manner. Neutral acetate of lead yields merely a slight 
 reddish precipitate. When the substance thus thrown down is removed from 
 the fluid by filtration, the filtrate is found to be as fit for dyeing and even to 
 give better and brighter colours than the primitive liquid. Hence it appears 
 that neutral acetate of lead precipitates only the super-oxidised matters, and, 
 moreover, removes from the decoction such compounds, tannin, for instance, 
 as may affect the purity and brilliancy of the dye. Subacetate of lead yields 
 a very abundant precipitate of a bluish colour; the filtrate from the liquid so 
 treated does not contain anything worth attention. Nitro-muriate of tin 
 yields with the decoction a red precipitate, which turns to a carmine-red of 
 the greater beauty the less the liquid was previously altered. The characters 
 here described are those which M. Persoz obtained while experimenting upon 
 decoctions of Bahia wood both old as well as freshly made. 
 
 M. Girardin's experiments on this topic differ in some particulars, but it 
 ought to be observed that in the first place the time elapsed since the rasping 
 of the wood has some influence, and, secondly, the different kinds of these 
 woods as met with in commerce may, and undoubtedly do, exhibit slight 
 differences when the decoctions are tested with reagents. 
 
 Brazil wood decoction is better fit for dyeing when it has been kept for a 
 good length of time in a cool place than when recently made. This fact, 
 
RED WOODS. 
 
 335 
 
 well known to all dyers, may be explained by the slow alteration and decom- 
 position of substances present in the decoction which affect the purity of the 
 hues; it is, moreover, possible that the colouring matter becomes reduced by 
 a special fermentation. 
 
 Dr. Dingier* has made known a simple method for purifying from the 
 yellow colouring pigment the decoctions made with some of the inferior woods, 
 viz., Bimas, Santa-Martha, Aniola, Nicaragua, Siam, and Sappan varieties, 
 which by this method are as excellent for dyeing as the best Fernambuco 
 wood. It consists in adding to the boiling liquid wood and small quantities 
 of very carefully skimmed milk. The coagulation of the casein causes the 
 precipitation of the yellow colouring matter along with the casein. Gelatin 
 also maybe applied for the purification of the inferior qualities of these woods. 
 If the shavings or raspings of the woods are moistened with water containing 
 2 kilos, of gelatin to the half hectolitre, and the mass left for some days heaped 
 together, the wood yields better results in the dye-beck, because^the colouring 
 matter is rendered more readily soluble, while the effect of a moist fermenta- 
 tion, which as observed by M. Leuchs, greatly improves some kinds of these 
 woods, may in the case mentioned have something to do with the improve- 
 ment of the quality. 
 
 The colouring glucoside of Brazil wood is only imperfectly known. Accord- 
 ing to Dr. P. Schutzenberger's experiments, it is a non-crystallisable substance 
 soluble in water in every proportion, and also in alcohol. Its taste is bitter or 
 sweetish ; its colour is a beautifully bright yellow when the substance has not 
 undergone any change. This glucoside may be obtained by concentrating the de- 
 coction in vacuum at the ordinary temperature of theair toone-tenth of its original 
 volume (sp. gr. 1*075), and then adding either sulphate of soda or common salt. 
 It is thereby precipitated in the shape of a pasty mass completely soluble in 
 pure water. The ordinary commercial extracts of the red woods (their sp. gr. 
 varies from f075 to I'iSa) yield, on the addition of water, a yellowish- 
 coloured flocculent precipitate, which would make it appear that the colouring 
 matter is more readily soluble in a concentrated than in a more dilute liquid, 
 but this reaction is explained by the partial decomposition and oxidation the 
 glucoside undergoes while the preparation of the extract is going on. The 
 product of the splitting-up is kept in solution owing to the state of concen- 
 tration, and by the aid of the saccharine matters present in that solution, and 
 the precipitation of the more or less modified glucoside, is due to the fact, 
 that on the dilution of the extract with water the solvent influence of the 
 other substances is decreased. 
 
 By the name of bresiline is understood the free colouring principle disengaged 
 from its glucosic combination. Bresiline was first studied and isolated by 
 M. Chevreul,t who obtained it by the following process: — The wood, pre- 
 viously ground, is exhausted with water, and the fluid obtained is evaporated 
 to dryness on a water-bath ; the dry residue is taken up by water again, and 
 the fluid shaken with some hydrated oxide of lead, in order to saturate the 
 acids present; the liquid is next filtered, and then again evaporated to dryness, 
 after which the residue is taken up by alcohol ; this solution is first somewhat 
 
 * See " Annales de Chimie," vol. xvii., p. 323. Dingler's " Polytechnisches Journal," 
 vol. xxv., p. 80. 
 
 1 See " Annales de Chimie" (first series), vol. lxvi., p. 225. 
 

 336 
 
 DYEING AND CALICO PRINTING. 
 
 concentrated by evaporation, next water is added, and it is then treated with 
 a solution of gelatin to remove tannic acid ; after nitration the fluid 
 is again evaporated to dryness, and the residue afterwards treated with 
 boiling alcohol. On cooling the bresiline is deposited in a crystalline state. 
 It often happens that in old decoctions of these woods (even when their 
 sp. gr. is as low as from roio to i"oi4), which have been kept for a long 
 time in contact with air in a cool place, an abundant deposit of bresiline in a 
 crystalline state is found at the bottom of the casks. Dr. Bolley has had an 
 opportunity of fully investigating this material, which was given to him by 
 Messrs. Muller, of Basel.* Dr. P. Schiitzenberger states that he also ob- 
 tained from the same parties a sample of this spontaneously-formed crystalline 
 deposit; on treating it with boiling alcohol, and evaporating it without the con- 
 tad of air and light, amber-yellow crystals of pure bresiline are obtained. The 
 shape of these crystals is that of hexagonal or klinorhombic prisms ; they 
 are soluble in water, alcohol, and ether ; the colour of the aqueous solution 
 is slightly more reddish than that of the alcoholic. Even the smallest trace 
 of ammonia is sufficient to turn these solutions intensely carmine-red. When 
 the crystals are kept in well-closed bottles they become darker, especially on 
 that part of the bottle which is most exposed to light. This is probably an 
 effect of oxidation favoured by the action of the light. When the alcoholic 
 solution of bresiline is preserved for a length of time, or is evaporated, 
 especially if slowly, it deposits, in addition to the yellow bulky crystals of 
 bresiline, small scaly crystals exhibiting a greenish cantharides-like reflection. 
 This substance, which contains nitrogen, is probably formed under the com- 
 bined influence of ammonia and oxygen. The crystals of bresiline are 
 anhydrous, and become decomposed when heated to from 130 to 140 . 
 
 According to the analyses of Bolley and Greift, the formula of this substance 
 is C22H20O7. As deposited from ordinary alcohol, which always contains 
 water, bresiline is obtained in the shape of golden-yellow crystalline needles 
 felted together ; this form belongs to the monoclinic system, and these crystals 
 contain 2 molecules of water of crystallisation, formula C 22 H2o0 7 + 2H 2 0. 
 This water is driven off at 8o° C. Dr. Bolley has not been enabled to obtain 
 any substitution compound by means of which this formula might be con- 
 trolled ; he states, however, that bresiline combines with bisulphite of soda, 
 yielding a colourless crystalline product : by this reaction bresiline ranges 
 with the aldehydes. 
 
 Dr. Schiitzenberger states that on heating pure bresiline and anhydrous 
 acetic acid to i40°he obtained a derivative insoluble in water and crystallising 
 from its alcoholic solution, forming bright yellow needles. Since bresiline is 
 thus acted upon by anhydrous acetic acid and combines therewith, it behaves as 
 an alcohol, and is in all probability therefore a polyatomic alcohol. Bresiline 
 heated along with ammonia to ioo° in a sealed tube and without excess of 
 air, yields an amidated colourless compound, which is very prone to decom- 
 pose in contact with air, and is a true base.f In this respect bresiline is 
 quite similar to the hematoxylin found in logwood; indeed the formula given 
 
 * See Bolley and Greift, " Schweizerische Polytechn. Zeitschrift," 18G4, vol. ix., p. 134. 
 t Schiitzenberger and Paraf, " Bulletins de la Societe Industrielle de Mulhouse," 
 vol. xxxi., p. 50. 
 
BRAZIL WOOD. 337 
 
 by Bolley for bresiline leads to the conclusion that bresiline and hematoxylin 
 only differ by the elements of phenol — 
 
 Bresiline C 2 2H 2 o0 7 
 
 Hematoxylin Ci6H I4 06 
 
 Difference C 6 H 6 = Phenol. 
 
 Some authors hold the opinion that bresiline and haematoxylin are identical, 
 but though there exist a great analogy between these substances they are not 
 identical, as is proved, moreover, by practice on the large scale as well as 
 by recent chemical researches. Hematoxylin when acted upon by nitric acid 
 yields only oxalic acid, whereas bresiline under the same conditions yields 
 trinitro-phenic or picric acid. Brazil wood, or the colouring matter contained 
 therein, is employed in dyeing in the following conditions : — 
 
 i. The wood itself, either reduced to shavings, raspings, or powder, serves 
 for the production of red, rose-red, amaranth colour, and carmine-red ; some- 
 times the wood is mixed in smaller or larger proportion with garancin for the 
 dyeing of the so-called garancin colours. The wood is used in a mechanically 
 divided state for the preparation of the decoction and concentrated extracts. 
 
 2. Decoction, or liquor of Brazil wood, obtained by boiling by means of 
 steam the raspings of the wood with from 18 to 20 times its weight of 
 water, or by the exhaustion of the wood by displacement with boiling water. 
 This liquor is used for dyeing, for the preparation of concentrated extracts, 
 and for the manufacture of the Brazil lakes. 
 
 3. The concentrated extracts having a sp. gr. of i'075, i - ii6, 1*162, or 
 even evaporated down to solidity. In these states the dye is more convenient 
 for carriage, whence the employment of such extracts is rather increasing. 
 The mode of preparation of these and similar extracts will be fully described 
 in a separate chapter. It need hardly be said that the quality of these extracts 
 varies greatly, not only in respect of the richness of the colouring matter 
 therein contained, but also as regards the purity and freshness of the shades 
 produced ; these differences depend partly upon the kind of wood used, and 
 partly also upon the care taken to prevent oxidation during the process. 
 
 4. Lakes, of which there are a great variety, made with Brazil wood, known 
 commercially by various names, as, for instance, Venice ball lake, Vienna, 
 Florentine, Berlin, and New lakes; they are chiefly used for the preparation 
 of coloured paper, for printing paper-hangings, and by artists, decorators, and 
 carriage painters. The mode of manufacture of these and other lakes will 
 also occupy our attention more fully hereafter. 
 
 Bresiline belongs to that class of pigments which cannot be fixed upon any 
 kind of textile fibre, except by the aid of a mordant, which, in this instance, 
 just as in the case of madder, not only fixes the pigment, but also determines 
 and develops the shade. With a piece of cotton previously mordanted with 
 alumina, hydrated oxide of iron, or a mixture of the two, we obtain with 
 bresiline, or any preparation of Brazil wood, colours which to some extent 
 resemble those produced by madder, or rather by cochineal. The alumina 
 mordants will produce red or rose-reds; the iron mordants, a greyish violet or 
 black ; the mixture of alumina and iron mordants yields a brown. Binoxide of 
 tin again yields red; the black is nothing very particular; the violet absolutely 
 ugly; the reds and roses are temporarily brilliant, but soon become dull, and 
 
 z 
 
SB IB SEE obbb 
 
 33« DYEING AND CALICO PRINTING. 
 
 disappear by the action of light. Hydrated oxide of chromium yields an olive 
 colour. All these colours are characterised by their looseness, and by being 
 readily affected by all kinds of reagents; they do not stand soaping, or even 
 ordinary washing with soap. The Brazil wood reds are rendered a violet-blue 
 by alkalies, while acids turn them yellow. 
 
 In calico dyeing and printing the red woods are used in connection with 
 garancin, as well as for the purpose of sightening the mordants temporarily. 
 The decoctions and extracts are frequently used for producing steam-reds : 
 the properly thickened liquor is mixed with — (i), acetate of alumina; 
 (2), protochloride of tin and oxalic acid; (3), a salt of copper (chiefly the 
 acetate), destined to promote oxidation during steaming. A good steam- 
 red can be made with a mixture of Brazil wood liquor with chloride of 
 aluminium and chlorate of potash. The chloride of aluminium is decomposed 
 by drying, and hydrochloric acid is given off, which reacts on the chlorate of 
 potash, liberating chloric acid, which oxidises the colouring matter, the ulti- 
 mate result being a compound of alumina with oxidised colour. This red is 
 very fast. These steam-colours contain, therefore, in solution all the mate- 
 rials required to form a red lake, which, by the steaming, is precipitated as 
 well as fixed upon the fibre. 
 
 The following are some of the reds and rose-reds used for steam and spirit 
 colours upon calico : — 
 
 Deep Red for Machine-work and Steaming. — 9 litres of a decoction of 
 St. Martha wood, sp. gr. 1-022 ; 1 litre of berry liquor, sp. gr. i - o6o ; 1*5 litres 
 of red liquor; 1-5 kilos, of starch ; 125 milligrms. of a solution of nitrate of 
 copper, sp. gr. 1-532. 
 
 Steam Rose-Red, upon Previously Mordanted t Cloth. — 2*5 litres of liquor, 
 sp. gr. 1-022 ; 5-5 litres of water ; 3 kilos, of gum ; 300 grms. of solution for 
 rose-red (see immediately below) ; 50 grms. of nitrate of copper, sp. gr. 1-618. 
 
 The Tin Solution for Rose-Red is made up of — 12 kilos, of nitric acid, sp. gr. 
 i'334 ; 3-25 kilos, of water; 1-25 kilos, of sal-ammoniac; 2-5 kilos, of bi- 
 chloride of tin ; 1-5 kilos, of pure tin (either Banca or Cornish). 
 
 Spirit-Red. — 5 kilos, of decoction of St. Martha wood, sp. gr. 1022 ; boil 
 therein 0-25 kilo, of gum tragacanth, and add 600 grms. of bichloride of tin, 
 sp. gr. 1-532 ; 180 grms. of salt for rose-red ; 150 grms. of nitrate of copper, 
 sp. gr. 1-532; 2-1 kilos, of tin solution as for rose-red. This colour is not to 
 be steamed, but becomes fixed by keeping the cloth hung up in a suitable 
 room. 
 
 Spirit-Rose is made up of 1 kilo, of the red mixture above mentioned and of 
 1-5 kilos, of gum tragacanth water. It is usual to apply a mixed mordant for 
 these colours, — that is to say, tin and alumina mixed, or each of these sepa- 
 rately; oxide of tin yields better colours on cotton than alumina. 
 
 Woollen tissues which are to be dyed with red woods are first mordanted 
 with protochloride of tin or an aluminous compound. For a quantity of 
 10 kilos, of wool, 1 kilo, of cream of tartar and 2 litres of a so-called red 
 solution are taken ; the wool is put in this mixture, and kept boiling for an 
 hour. The red solution consists of 8 litres of water, 400 grms. of common 
 salt, 1-25 kilos, of tin, and 8 litres of nitric acid. The alum-bath suitable for 
 10 kilos, of wool consists of 2 kilos, of alum and 20 grms. of sulphuric acid. 
 The woollen goods are left boiling an hour. 
 
 The employment of the red woods, at least for the production of red steam- 
 
SANTAL WOOD. 
 
 339 
 
 colours upon wool and silk, and even for dyeing, has been in some cases 
 superseded by the new aniline colours, but they are used for clarets and browns 
 along with orchil and other colouring matters. They are also largely used in 
 dyeing so-called " mock crimsons," in imitation of those produced with 
 cochineal. In scarlet and crimson coburgs, and other mixed goods, the cotton 
 warp is got up with a wood of this class in conjunction with a per-salt of tin. 
 The best method of testing the woods, or the extracts thereof, for their value 
 is a mode of assay founded upon either a dyeing or printing process, con- 
 ducted as follows : — Take 10 grms. of the material to be tested, if wood 
 it must be previously pulverised, and also a piece of 25 square centimetres of 
 cotton cloth, mordanted, as indicated above, for testing garancin ; put these 
 materials into a suitable glass vessel, wherein is poured £ litre of water ; heat 
 the vessel in a water-bath, and keep the dyeing process up for half an hour, 
 care being taken to stir the contents of the vessel about with a glass rod. 
 The pattern, after having been washed with cold water, is placed for some 
 time in a bran-bath, at 8o°, and afterwards again washed with cold water, and 
 dried. This mode of testing requires the use of a standard sample for com- 
 parison. 
 
 Commercial samples of ground woods often contain an excess of moisture. 
 If on drying at 212 F. the loss exceeds 32 per cent, there is good cause for 
 complaint. If allowed, when very moist, to lie long in large heaps, heat is 
 developed, and the colouring matter is gradually destroyed. The extract, at 
 io° Baume (sp. gr. i"075), is about five times as strong as the wood. 
 
 If preferred, the following colour mixture may be made up : — Extract of the 
 wood, 20 grms. ; alumina mordant, 200 grms.; water, 140 grms.; pulverised 
 gum, 160 grms. After the latter substance has been dissolved the fluid should 
 be passed through a fine sieve. This mixture is printed on by means of a 
 roller; if calico, by means of block-printing; if muslin is the fabric upon 
 which it is desired to test, after drying the fabric so treated is steamed and 
 washed. This assay also requires a standard sample of extracl. 
 
 The red dyes produced by these woods or extracts, and fixed upon fabrics, 
 are recognised by the following tests : — Like the reds produced by madder and 
 cochineal, they are destroyed by chlorine and hypochlorous acid : on incine- 
 ration they leave a compound of alumina or tin, according to the mordant 
 employed ; but the reds produced by the woods are also destroyed by boiling 
 soap solution, which distinguishes them from madder reds. When successively 
 immersed, first in hydrochloric acid, and next in lime-water, the red wood 
 shades are turned violet, which is destroyed by boiling soap solution. Con- 
 centrated sulphuric acid turns the red of the woods to deep cherry-red, while 
 it converts cochineal to an orange-yellow. 
 
 B. Close or Insoluble Class. 
 The principal woods of this class are santal wood, cam wood, and bar 
 wood. These woods are of a more resinous character than Brazil wood and 
 its allies, yielding faster dyes, but from the insolubility of the colouring 
 matters they cannot be used in the state of extracts. 
 
 Sanders Wood, Santal Wood, or Red Sanders. 
 This wood is the product of Pterocarpus santaliiius, a tree growing in India, 
 Ceylon, Timor, and other tropical parts of Asia. The wood is hard, of a 
 
 z 2 
 
Iw HhBB B E 
 
 BB 
 
 340 
 
 DYEING AND CALICO PRINTING. 
 
 high specific gravity, viz. i'Oi4, very dry and compact, of a blackish-brown 
 colour externally, while within it is red. The fibres of this wood occur 
 alternately in layers running in opposite directions ; as a consequence thereof, 
 when an attempt is made to plane it, it will exhibit alternately a polished and 
 a rough torn-up surface. For dyeing purposes the old wood is the best, 
 because it is richer in colouring matter. 
 
 Santal wood is met with in commerce in the state of a powder specifically 
 lighter than water, with a smell like that of orris-root : its taste is somewhat 
 aromatic. This substance contains pigment, gummy and astringent matters, 
 chloride of calcium, sulphate of lime, chloride of potassium, organic potassa 
 salts, phosphate of magnesia, alumina, oxide of iron, and silicic acid. The 
 colouring matter of santal wood is insoluble in cold water, very slightly soluble 
 in boiling water, readily soluble in alcohol, ether, acetic acid, and caustic 
 alkalies, and precipitable from its solution therein by an acid. 
 
 The chemistry of this product is by no means quite complete. Pelletier 
 was the first who discovered and isolated santalin as a red resin, the solubility 
 and properties of which are those above described. Meier prepares santalin 
 by treating the wood with ether; the concentrated solution yields the sub- 
 stance in a crystalline yet impure state. These crystals are first washed with 
 water, and next re-dissolved in alcohol ; the alcoholic solution is precipitated 
 by acetate of lead, and the ensuing precipitate washed with boiling alcohol, 
 and next decomposed by means of sulphuric acid in the presence of alcohol. 
 After removing the sulphate of lead, the previously concentrated alcoholic 
 solution deposits santalin, in the shape of small crystals, of a beautiful red 
 colour, fusing at 104 . Dr. Dussauce's plan of preparing santalin is by pre- 
 cipitating the alcoholic extract: of the wood by means of hydrated oxide of 
 lead. After washing, the precipitate is dissolved in acetic acid, and to this 
 solution a large quantity of cold water is added, which indeed precipitates the 
 colouring matter, but in a rather impure state, since the dye thus obtained 
 does not yield good results. 
 
 Santal Wood contains on an average about 16 per cent of santalic acid. 
 According to the researches of Weyermann and Haeffely the composition of 
 santalin is C I5 Hi 4 5 . This result was controlled by the analysis of a baryta 
 salt of santalin, obtained in the shape of a violet crystalline precipitate 
 by adding chloride of barium to an ammoniacal solution of santalin : the 
 formula of this compound was found to be C 30 H 2 6BaOio. Dr. Bolley considers 
 that santal wood contains two different colouring matters, one of which is 
 richer in oxygen but poorer in hydrogen : this is the material occurring in the 
 old dark-coloured wood. The other is found in the younger and paler variety. 
 According to the researches of Meier and Wimmer santalin is accompanied 
 by divers red and brown coloured matters, more soluble in water than santalin 
 itself and the products of its oxidation. This assertion is certainly substan- 
 tiated by the fact that the young twigs of the Pterocarpus santalinus are inter- 
 nally yellow-coloured, and only become red by the action of the air. 
 
 Santalin exhibits the following properties : — It is a beautiful red crystalline 
 powder, almost insoluble in water, soluble in alcohol, ether, and acetic acid : 
 the colouring matter is very readily withdrawn from the acetic acid solution 
 by albuminous substances, which retain it energetically ; alkalies dissolve 
 santalin, yielding deep violet-red solutions, from which it is thrown down un- 
 altered by acids. Santalin fuses at 104 . 
 
BARWOOD. 
 
 34i 
 
 According to Prof. Girardin, the alcoholic tindure of santal wood exhibits 
 the following reactions : — Addition of water causes a yellow turbidity; with 
 alkalies the colour turns carmine ; lime-water produces a reddish-brown 
 ochreous precipitate ; protochloride of tin a blood-red precipitate ; bichloride 
 of tin a brick-red precipitate ; per-salts of iron a red-brown precipitate ; salts 
 of lead a violet precipitate ; corrosive sublimate a scarlet precipitate ; salts of 
 silver a red-brown precipitate. 
 
 Santal wood is used for some peculiar red shades upon wool and cotton 
 after having been mordanted with alumina or oxide of tin, and also as a bottom 
 for the so-called Nemours or "national blue" upon wool. Mixed with other 
 dyes, it is used for the production of brown, bronze, and olive colours. Santal 
 wood dyes wool permanently, even without the aid of any mordant. 
 
 The following woods met with in commerce belong, as far as is known, to 
 the same category as santal wood : — 
 
 Caliatur or Cariatur Wood is imported from India in blocks of from 2 to 
 3 metres in length ; it is a hard, compad, and imperishable wood, internally 
 bright red, and is superior to santal wood as a dye-stuff, but is rather expensive, 
 and is rarely used. 
 
 Madagascar Wood is of a wine-red colour. 
 
 Barwood may be considered as the type of the insoluble class of red 
 woods. It is obtained from the west coast of Africa, especially from Sierra 
 Leone and Angola. The botanical name of the tree is Bapliia nitida, which, 
 singularly enough, is also said to yield camwood. In the log barwood is 
 compact, and has an orange colour when polished. When rasped — the state 
 in which it is generally met with in trade— it is a rough, harsh, red powder, 
 without smell. Cold water, after maceration for five days with the ground 
 wood, acquires merely a pale fawn-colour, about 085 per cent only of colour 
 being taken up. Boiling water takes up about 7 per cent of colour, which on 
 cooling is almost entirely re-deposited as a reddish powder. Hence all 
 attempts to prepare from it a liquor or extract fit for use in dyeing and printing 
 have failed. In alcohol the tindorial principle is more soluble, but it is only 
 by repeated treatment with boiling spirit that the wood is entirely exhausted. 
 The amount of colouring matter is high, averaging 23 per cent. In caustic 
 soda and ammonia it dissolves with a violet-red hue, and is re-deposited on 
 neutralising the liquor with an acid. An attempt has been made to utilise 
 the solvent power of alkalies in order to obtain an extract, but the brightness 
 and permanence of the colour are so much impaired that the process is of no 
 pradical value. Acetic acid extracts the colour, and becomes of a dark brown 
 hue, but if this extrad is mixed with water it dyes very flat and meagre 
 shades. 
 
 The alcoholic solution gives the following precipitates : — With proto-salts 
 of iron, a violet ; with salts of copper, a brownish-violet ; acetate of lead, a 
 deep violet ; chloride of tin, a light red ; sulphate of zinc, a bright red ; tartar 
 emetic, a cherry-:ed ; nitrate of bismuth, brilliant crimson ; corrosive subli- 
 mate, a brick-red. 
 
 Barwood is very extensively used in producing upon cotton-yarn the well- 
 known " barwood red." This is a shade much more permanent than any 
 obtained from the soluble red woods, and is used as a cheap substitute for 
 Turkey-red. The cotton is first well mordanted with an astringent, — generally 
 
t '- v»; ."yJV V> -< >*• V} M «#-,v A ■ 
 
 ^^^^^H^H 
 
 IMMI|l|<yfl^^M|«jMM« 
 
 342 
 
 DYEING AND CALICO PRINTING. 
 
 sumach, — and with " barwood spirit," a preparation of tin, receipts for which 
 will be given in a special chapter. It is then boiled along with the loose 
 wood. This process presents two interesting peculiarities : absolute contact 
 between the ware and the mordanted goods appears necessary, and, unlike 
 ordinary cotton-dyeing operations, it is carried on at a boiling heat. A reduc- 
 tion of temperature is fatal to a good result. 
 
 Cam Wood or Kambe Wood. — This dye ware is brought from the Gaboon 
 and Sierra Leone. It yields its colouring matter to water much more freely than 
 barwood and sanders, but is still not sufficiently soluble to produce an extract. 
 The shades which it yields are, under all circumstances, more yellow than 
 those produced by Brazil wood. It is used by woollen dyers to produce certain 
 fast reds, maroons, and especially browns of a very permanent character. It 
 also serves as a ground or " bottoming" for certain blues, whether produced 
 with the vat, extract of indigo, or with anilines, especially Guernsey blue. 
 
 Logwood, or Campeachy. 
 
 Logwood, Campeachy wood, called formerly " blue wood " and " black 
 wood," is met with in commerce in the shape of large irregular-shaped blocks, 
 weighing on an average about 400 lbs. Externally this wood is deep brown- 
 red, but within, where no air has been in contact with it, its colour is brighter. 
 It is very hard, and capable of taking a good polish ; the blocks or billets are 
 usually full of cracks and crevices ; its taste is saccharine and astringent, and 
 it colours the saliva red. 
 
 The Hcvmatoxylon campechianum is the tree which yields the wood in ques- 
 tion. This tree also belongs to the natural order Leguminosa, and is a native 
 of the entire warmer portion of South America, the larger American Antilles, 
 viz., Jamaica, Cuba, St. Domingo, and also of Mexico. This wood has been 
 known and used in Europe from a short period after the discovery of America, 
 and since 1715 the tree has been cultivated in Jamaica. This wood has been the 
 subject of an Ait of Parliament, made in the twenty-third year of the reign of 
 Queen Elizabeth, by which its use was forbidden as a dye-material, because it 
 did not yield fast colours. This Act of Parliament was repealed, or at least 
 superseded, by an order in council of Charles II., which sets forth that 
 whereas great improvements had been made in dyeing generally, and greater 
 skill applied especially as regards the means of obtaining faster colours from 
 " black wood," the dyers might be allowed to use it, and Elizabeth's Act might 
 remain in abeyance. 
 
 The following are the chief varieties of logwood, distinguished by names 
 chiefly derived from the localities of exportation : — Spanish log, or campeachy 
 wood, from Yucatan and Mexico; English logwood, from Jamaica; wood 
 from St. Domingo ; Honduras (British) wood ; Martinique, and Guadeloupe 
 or French wood ; the last two kinds of less value as dye material than the 
 others. 
 
 To the researches of Chevreul (1810) and to those of the late Dr. Erdmann, 
 and of Runge of more recent date, we owe our knowledge of the properties and 
 composition of the colouring matters of logwood. The colouring matter of 
 logwood exists in the aqueous decoctions of that wood in three different 
 forms : — In an oxidised state ; as colourable matter, and is then known by, or 
 designated as, haematoxylin ; and, lastly, as a glucoside. The oxidised portion 
 
LOGWOOD. 
 
 343 
 
 is produced by the action of the atmospheric oxygen upon the wood, and it is 
 to that alteration that the aqueous decoction owes its darkish tint. It is quite 
 clear that this alteration may be more or less advanced, and, as a consequence 
 thereof, common salt causes in concentrated liquid extracts (unless they have 
 been made in vacuum) a precipitate of an almost black-coloured resinous 
 substance, while in the freshly-made aqueous decoction the precipitate is of a 
 bright brick-red. The colouring power of the wood is largely increased if it 
 is suffered to ferment, after having been rendered moist, by being placed in 
 heaps, on a well-made wooden floor, the height of the heaps attaining from 
 i to i*5 metres : the wood thus heaped up should be frequently turned over, so 
 as to renew the currents of air, and to prevent also a too great elevation of 
 temperature. If " heating," as it is technically called, once sets in, it is not 
 easily checked, and the colouring matter is soon entirely destroyed. This 
 fermentation has the effect of partly eliminating and greatly modifying those 
 substances which accompany haematoxylin : as a proof thereof we may state 
 the fact that the so-fermented powder causes less soiling of the white portions 
 of the cloth in the dyeing process. The increase of colouring power observed 
 under these conditions is, in all likelihood, due to a saponification of the 
 colouring glucosides. 
 
 Haematoxylin in a crystalline state was first obtained by Chevreul, by ex- 
 hausting with alcohol the dry residue left on cautiously evaporating the 
 aqueous extract of logwood. Prof. Erdmann prepared this substance by 
 treating either the aqueous extract or the finely-pulverised wood, after previous 
 admixture with pulverised quartz, with ether. The solution so obtained is 
 evaporated to the consistence of a thick syrup, mixed with water, and, on 
 being left standing by itself, the crystallised hematoxylin is deposited after 
 some days. It now and then happens that, at the bottom of the casks or 
 vessels wherein liquid extract of logwood is kept, brilliant crystalline tufts of 
 haematoxylin are fourid in the shape of prismatic crystals, externally of a 
 brownish metallic hue, but bright yellow within. The following are the 
 properties of haematoxylin : — Bright yellow transparent crystals, yielding 
 a yellowish-white powder, and belonging to the tetragonal system ; in taste 
 very like liquorice root ; sparingly soluble in cold water, but far more readily 
 so in alcohol, ether, and boiling water. The prismatic crystals contain 15*1 
 per cent of water. When a hot saturated solution of haematoxylin is left to 
 cool in a stoppered bottle it deposits, after some time, granular irregular crys- 
 tals, containing 5*6 per cent of water. Both these crystalline forms correspond 
 to two different states of hydration. 
 
 According to Erdmann's analysis the formula of haematoxylin is C16H14O6; 
 the prismatic crystals contain 3 atoms of water, and the granular crystals 
 only 1 atom. A portion of the water is expelled at ioo°, but the last traces 
 can only be volatilised at a higher temperature. When haematoxylin is heated 
 it first fuses in its water of crystallisation ; by continued and increased heat 
 it is decomposed, leaving behind an abundant carbonaceous residue. 
 
 Haematoxylin is not volatile, and when quite pure ads as a weak acid, 
 yielding with bases colourless compounds, which exhibit, however, a very 
 great tendency to absorb oxygen and become coloured : we obtain, for instance, 
 a precipitate which is at first white, but becomes rapidly bluish when exposed 
 to air, and finally assumes a reddish-brown tinge. It is extremely difficult to 
 

 EBBH 
 
 344 
 
 DYEING AND CALICO PRINTING. 
 
 obtain a white combination of hematoxylin and the alkalies, because the 
 affinity of that substance for oxygen is so greatly increased by the presence of 
 potassa or soda, and it is, moreover, difficult to have hematoxylin in solu- 
 tion so completely free from any trace of oxidation, that the addition even of 
 any alkali to a liquid containing it brings out at once a violet tint, which 
 darkens rapidly on exposure to air. 
 
 A colourless alkaline haematoxylate may be obtained by taking advantage of the 
 sparing solubility of these salts in a liquid containing common salt in solution. 
 A cold decoction of logwood, or a solution of hematoxylin, is first saturated 
 with common salt, and next a solution of caustic soda is gradually added ; 
 the first portion of the ensuing precipitate will be more or less coloured, be- 
 cause it carries down the oxidised substance, but by a rapidly managed 
 filtration this purlion of ihe precipitate may be eliminated, and en continued 
 addition of alkali to the filtrate a white precipitate of haematoxylate of soda 
 will be obtained, which becomes, however, rapidly coloured on access of air. 
 Neutral and basic acetates of lead yield, with solutions of haematoxylin, 
 bluish-white precipitates, which also become rapidly darkened by contact with 
 air. Solutions of salts of gold and silver yield precipitates which soon alter, 
 and deposit reduced metals; salts of copper also precipitate haematoxylin 
 solutions. Protochloride of tin produces a permanent rose-coloured preci- 
 pitate ; solution of alum gives a bright red colour, but no precipitate is at 
 first formed, though after some time a slight blackish-coloured precipitate 
 ensues ; acetate of alumina gives a fine purple. Dilute mineral acids have 
 no particular action upon hasmatoxylin ; concentrated nitric acid converts it 
 into oxalic acid ; chlorine converts it into a brown non-crystallisable substance, 
 not thoroughly examined ; chromic acid and bichromates are, in contact with 
 haematin, instantaneously reduced, forming a deep black, which is extensively 
 applied in cotton dyeing and printing. 
 
 The characters and reactions of the decoction of logwood, as first described 
 by M. Chevreul, refer to mixtures of colourable matter (hasmatin) and actual 
 colour (haematein). Dilute mineral acids turn the decoction yellow ; if the 
 acids are concentrated a red is produced. Since sulphuretted hydrogen enters, 
 by causing deoxidation, into a colourless combination with the already more 
 or less oxidised substances present, that gas or its aqueous solutions bleach 
 the decoction. Sulphurous and carbonic acids turn the decoction yellow ; 
 alkalies produce first a red, and ultimately a violet; baryta, lime, and hydrated 
 metallic oxides yield blue precipitates ; basic salts act as bases, and acid 
 salts like acids ; aiuminatc of soda yields an abundant violet blue precipitate, 
 insoluble in excess of alkali — this test is so delicate and so characteristic that 
 by means of it logwood may be detected in a mixed decoction with great 
 facility.* Hydrated protoxide of tin combines with the colouring matters of 
 logwood decoction in the same manner as the alkalies, yielding a violet-lake. 
 Protochloride of tin yields with the decoction a violet precipitate. Stannic 
 hydrate acts as an acid, and turns logwood liquor red. Solution of alum 
 yields first a yellow colouration, which after a while turns red. Salts of iron 
 yield a blue-black (hence the application of logwood for the preparation of 
 writing ink). Salts of copper give a blue precipitate. Salts of zinc yield a 
 
 * E. Mathieu-Plessy, "Bulletin de la Societe Industrielle de Mulhouse," vol. xxvii., p. 403. 
 
LOGWOOD. 
 
 345 
 
 deep purple precipitate ; corrosive sublimate, an orange precipitate ; chloride 
 of antimony, a carmine precipitate ; nitrate of bismuth, a beautiful violet 
 precipitate. 
 
 When haematin is treated with caustic ammonia it gives a violet liquid, 
 which, when heated to ioo° in closed vessels for some time, becomes nearly 
 colourless, owing to the reducing action of the ammonia. On cooling, this 
 liquid becomes almost solid, from the precipitation of a white flocculent sub- 
 stance, soluble in acids, with a bright yellow colouration, and re-precipitable 
 from that solution by alkalies, with a white colour. This substance, which 
 contains the elements of hematoxylin and ammonia, acts as an organic base, 
 and it becomes rapidly blue in contact with air. Dr. Schiitzenberger ascer- 
 tained that this body contains nitrogen combined in another form — an ammo- 
 niacal salt. 
 
 When haematoxylin is heated to 140 , with anhydrous acetic acid, it yields 
 a bright brown acetic derivative, insoluble in water, but soluble in alcohol. 
 On evaporating the alcoholic solution the material exhibits an amorphous, 
 resinoid, very fusible substance. Prof. Erdmann gave the name of haematein 
 to the product of the action of haematoxylin when it absorbs oxygen in the 
 presence of an alkali. When a saturated solution of haematoxylin in ammonia 
 is gently heated, and shaken about so as to promote contact of air, the liquid 
 assumes a deep cherry-red colour and deposits granular crystals of haemateate 
 of ammonia. When this is decomposed by acetic acid there is formed a bulky 
 brown-red precipitate, which, on drying, becomes deep green and exhibits a 
 metallic hue. When reduced to a powder this body is red. Haematein is 
 sparingly soluble in cold water, but more readily at a boiling heat ; it is 
 soluble in alcohol, and slightly soluble in ether ; its composition is expressed 
 by Ci6H I2 06, differing from haematoxylin only by two atoms less hydrogen. 
 Its formation is shown by the following formulae : — 
 
 C l6 H I4 6 + O = C l6 H I2 6 + H 2 0. 
 
 Alkalies and ammonia dissolve haemateine, yielding solutions which are at 
 first blue or purple, but become gradually brown on contact with air and ad- 
 vancing oxidation. Haemateate of ammonia is a deep violet powder, formed 
 of very small microscopical four-sided prisms, which are transparent, soluble 
 in water, with a purplish colour, and in alcohol with a red-brown : the 
 haemateate of ammonia loses its ammonia at 100°, or even in vacuo, over 
 sulphuric acid. This salt precipitates solutions of metallic salts, giving rise 
 to coloured precipitates, — as, for instance, with sulphate of copper, a violet- 
 blue ; protochloride of tin, violet ; iron alum, a black precipitate ; nitrate of 
 silver is reduced to the state of metal. Haemateine is therefore only the first 
 term of the process of oxidation of haematoxylin. When the oxidation pro- 
 ceeds farther ulmic compounds are formed, as is the case with the alkaline 
 solutions and under the influence of bichromate of potassa. Sulphuretted 
 hydrogen decolourises haematein while combining with it, but does not re- 
 convert it to haematoxylin ; but probably the more energetic reducing action 
 of hydriodic acid would effect the re-conversion. 
 
 The colourable substance of logwood acts as a phenol, capable of entering 
 into combination with bases as well as with the radicals of the acids. In its 
 general properties haematoxylin very much resembles bresiline, but they are not 
 identical : it is probable, however, that haematin may be converted into 
 bresiline by the addition of the phenyl radical. 
 

 » 
 
 346 
 
 DYEING AND CALICO PRINTING. 
 
 For industrial purposes — that is to say, in dyeing — are used (1), the wood 
 reduced to powder or shavings ; (2), the cold infusion ; (3), the decoction ; 
 (4), the extracts, in a more or less concentrated state, and sometimes even 
 inspissated so as to form a dry material. The tinctorial value of these sub- 
 stances is estimated by a process of dyeing on the small scale precisely similar 
 to that described for the Brazil woods ; but since logwood is richer in colouring 
 matter, only 5 grms. weight of that wood are taken for 25 square centimetres 
 of tissue. The mode of manufacture of the extracts of logwood on the large 
 scale will be afterwards separately treated. Logwood yields, with aluminous 
 mordants, deep violet-grey shades ; with proto-salts of iron a bluish-black, and 
 with per-salts a black of a more brownish shade ; a mixture of both yields a 
 finer black than either separately. With chromates of potash logwood yields 
 a black colour, which on exposure to light gradually takes a greenish shade. 
 These colours are, however, unstable, and readily destroyed by the action of 
 light, soap, alkalies, and acids. Logwood violet or logwood black is therefore 
 very readily recognised by simply applying to the dyed fabric a drop of a some- 
 what concentrated acid, which has the effect of turning these colours red, 
 while if the black be that of nut-galls the colour is changed, but not turned red. 
 Logwood is very extensively used in the dyeing of cotton, wool, silk, leather, 
 and in the preparation of some steam-colours : the tone of the colours varies 
 according to the mode of application. 
 
 Logwood blue is produced upon cotton by working the goods in a beck con- 
 taining a liquor or decoction of logwood, varying in specific gravity from 1*007 
 to i'oi6, with the addition of acetate of copper. The liquid is raised from an 
 ordinary atmospheric temperature to 50 in one hour. The blue thus pro- 
 duced resembles a vat-blue, and is very intense : this process of dyeing may 
 be executed by alternately passing the woven fabric through a copper bath 
 and logwood bath. 
 
 In order to produce uniformly black-coloured grounds upon cotton, it is first 
 mordanted with a suitable mixture of pyrolignite of iron and acetate of 
 alumina, sometimes with the addition of nitrate of soda, to promote the 
 oxidation of the iron. The dyeing operation is performed starting at 30 , and 
 heating up to boiling; sumach or quercitron are occasionally added to the 
 dye-beck. Uniformly black-dyed fabrics generally admit of being discharged if 
 treated with oxalic acid. The printing of logwood colours upon cotton does 
 not differ from the method just described herein, excepting that the aluminous 
 or ferric mordant is printed on by the engraved roller instead of being uniformly 
 padded. In order to fix the chrome logwood black, as it is termed, a mixture 
 of a logwood liquor, properly thickened, is printed on, and, after drying, the 
 fabric is placed in a bath of bichromate at 40 . The black colour thus 
 produced is fast as compared^ with the other logwood blacks, and is the result 
 of a special oxidation which hematoxylin undergoes under the influence of 
 chromic acid : the lake thus produced contains oxide of chromium. Another 
 kind of logwood black is obtained by printing a mixture of a logwood 
 decoction to which protosulphate of iron and persulpho-nitrate have been 
 added, and by passing the cloth so prepared through tepid milk of lime. By 
 the aid of the bichromate process cotton-yarn or woven fabrics may be very 
 cheaply dyed black: to 500 litres of the logwood extract, 1-007sp.gr., are 
 added 1*5 kilos, of bichromate of potassa, previously dissolved in water, to 
 
LOGWOOD. 
 
 347 
 
 which solution are added 3-5 kilos, of hydrochloric acid. The goods are 
 placed in this mixture, and the temperature raised to boiling, when the fibre 
 takes a deep indigo-blue, which passes into bluish-black after washing in 
 water. The two last-mentioned dyeing processes resemble those in use for 
 the fixation of catechu colours: there is, indeed, a similarity of behaviour, as 
 far as the dyeing process is concerned, between hematoxylin and catechin. 
 Uniform greys are obtained by means of logwood, by first mordanting the 
 fabric by working in a weak solution of pyrolignite of iron. After oxidation 
 and cleansing, the goods are dyed by being winced in a dye-beck containing 
 the logwood reduced to powder, or in the shape of shavings, and by elevating 
 the temperature gradually to boiling. The decoctions and extracts of logwood 
 serve for the preparation of a very large number of steam and application 
 colours, of the making up of which we quote the following as representing 
 the ingredients : — 
 
 Steam-Black on Cotton. —Extract of logwood, at 6° Baume (sp. gr. 1-044), 
 5 kilos. ; acetic acid, 1*25 kilos. ; pyrolignite of alumina, at io° Baume (sp. gr. 
 1-07^), 1-25 kilos.; pyrolignite of iron, at 14 B. (sp. gr. 1*106), 1-25 kilos.; 
 white starch, 750 grms. This mixture is to be boiled for an hour, and kept 
 stirred until cold. It is next printed on, dried, and steamed. 
 
 Steam-Black for Roller-Printing. — Extract of logwood, at 17 B. (sp. gr. 
 i"i34), 5-5 litres ; pyroligneous acid, at 2° B. (sp. gr. roi4), 2 litres ; pyrolignite 
 of iron, at 12 B. (sp. gr. rogi), 6 litres ; starch, 2-125 kilos. ; gum substitute, 
 2-125 kilos. ; oil, 0*12 litre. 
 
 Steam- and Application-Black for Roller-Printing. — Water, 2-5 litres ; pyro- 
 lignite of iron, at 14° B. (sp.gr. 1-106), 11 litres; pyroligneous acid, at 2 
 (sp. gr. 1-007), 4*5 litres; extract of logwood, at 20 B. (sp. gr. 1*162), 
 675 litres ; white starch, 3-508 kilos. ; gum substitute, 4 kilos. ; Gallipoli oil, 
 1*5 litres. 
 
 Bluish Application-Black. — Logwood decoction, at 4 B. (sp. gr. 1-029), 
 20 litres ; white starch, from 3 to 4 kilos. This mixture is boiled, and after it 
 has become cool there are added to it, of chlorate of potassa, 40 grms., and of 
 rose-red liquor (mordant for), 2 kilos. The black produced by this mixture is 
 very rapidly developed by exposing the fabrics in heated ageing-rooms. 
 
 Extract of logwood is also used mixed with the extracts of the red woods 
 and of quercitron, for the production of brown and pomegranate application- 
 colours upon cotton, while the logwood extract by itself is applied for steam- 
 and application-lilacs. The following may serve as instances of the making 
 up of these colours : — 
 
 Deep Lilac Colour for Block- Printing.— Water, 48 litres ; extract of logwood, 
 at io° B. (sp. gr. 1-075), 8 litres ; gum, 17 kilos. ; alum, 3-8 kilos. ; nitrate of 
 copper solution, at 50 B. (sp. gr. 1-532), 250 grms. 
 
 Steam-Lilac for Roller-Printing. — Logwood extract, at 8° B. (sp. gr. 1-060), 
 8 litres; acetate of alumina, at 15 B. (sp. gr. 1/116), 1-5 litres. This acetate 
 is made up of — Water, 5 litres ; alum, 2*5 kilos. ; acetate of lead, i - 8 kilos. ; 
 oxalic acid, 240 grms. ; gum, 1-25 kilos. 
 
 Application-Lilac. — Logwood decoction, at 5° Baume (sp. gr. i'036), 10 litres ; 
 water, 4 litres ; gum, 8 kilos. ; sal-ammoniac, 750 grms. ; salt for rose-red,* 
 
 * Has been described above under Brazil Wood, and is prepared as follows : — 12 kilos, nitric 
 acid, at 30° B. (sp. gr. fzbi); water, 3-25 kilos. ; sal-ammoniac, 125 kilos. ; bichloride of tin, 
 2"5 kilos. ; pure metallic tin, 1-5 kilos. 
 

 99S9B wy 
 
 ' S9I BBH 
 
 348 
 
 DYEING AND CALICO PRINTING. 
 
 1-85 kilos. ; sulphate of copper, 250 grms. ; oxalic acid, 150 grms. In addition 
 to the ingredients just named mordants are added, consisting of iron and 
 alumina salts, or salts of tin : the addition of the salt of copper and of sal- 
 ammoniac is oxidising. Instead of the salt of copper the sulphuret of that 
 metal may be employed, as proposed by M. Lauth. 
 
 Steam-Grey for Roller-Printing. — Water, 5 litres; pyroligneous acid, at 2° B. 
 (sp. gr. 1-014), o - 5 litre; decoction of logwood, at 2° B. (sp. gr. 1-014), T 9 s th 
 litre ; quercitron decoction, of the same strength, ,»jth litre ; sal-ammoniac, 
 0-25 kilo. ; gum substitute, 1*5 kilos. To every litre of this mixture are added 
 60 grms. of the undermentioned blue mordant, made up of — Ferrocyanide of 
 potassium (yellow prussiate), 500 grms. ; chlorate of potassa, 150 grms. ; 
 water, 0-75 litre ; sulphuric acid, at 65 B. (sp. gr. 1-827), 640 grms., diluted 
 with 012 litie of water : the acid and water should be mixed and left to cool 
 before being added to the rest of the ingredients. 
 
 These steam-greys may be varied in divers ways ; for instance — Logwood 
 decoction at 2° B. (sp.gr. 1014), 2*5 litres ; pyroligneous acid, at 2 B. (sp. gr. 
 i , oi4), 1 litre ; red liquor (mordant as used for madder colours), at 8° B. 
 (sp. gr. 1-060), 2-5 litres ; water, 13 litres ; pyrolignite of iron, at 10° B. (sp. gr. 
 1*075), 2*5 litres ; starch, 2*25 kilos. 
 
 Application-Grey. — Water, 1 litre. The following substances should be 
 dissolved therein or added thereto : — Gommeline, 1 kilo. ; solution of gum 
 tragacanth, 0-125 kilo.; pyroligneous acid, at 3 B. (sp. gr. 1-022), 0-060 litre; 
 solution of sulphate of iron, at 20 B. (sp. gr. 1-162), 0*18 litre [such a solution 
 contains about 28 per cent of the crystallised salt] ; red liquor, as used for 
 madder, o - o6o litre. 
 
 Logwood decoctions also enter into the preparation of olive, reseda, oak- 
 brown, and some other dyes. In dyeing wool and silk with logwood, blue is 
 obtained on wool by mordanting it with alum and cream of tartar, and im- 
 mersing the woollen material in a boiling bath of logwood, or extract thereof, 
 to which sulphate of copper has been added, 
 
 For the so-called king's blue the following quantities are used : — For, 
 100 kilos, of wool : alum, 10 kilos. ; cream of tartar, 2 kilos. ; sulphate of 
 copper, 1 kilo. ; shavings of logwood, a sufficient quantity. 
 
 Logwood is also employed for the production of French blue upon wool, 
 along with indigo, santal, orchil, and nut-galls. 
 
 The well-known excellent Elbeuf and Sedan blacks, on broad cloth, are 
 dyed first more or less deep blue, by means of the indigo vat, and afterwards 
 dyed black, in a boiling bath made up of )ogwood ; sumach, and sulphate of 
 iron. If the cloth is not first indigo vatted, it is mordanted with alum and 
 red argol, and dyed in a bath to which logwood, fustic, orchil, alum, argol, 
 and copperas are added. 
 
 A fast black upon wool, which does not fade, is produced with logwood, when 
 the woollen fabric is first mordanted with bichromate of potash and cream 
 of tartar, and next dyed with logwood, orchil, and alum. On the Continent 
 the best blacks upon woollen tissues of superior description are very generally 
 obtained by means of madder. 
 
 The fastest logwood-black upon woollen and worsted goods is that obtained 
 by the old logwood and copperas process. It is now little used, not from any 
 imperfection in the results, but because it requires more time, labour, and 
 
LOGWOOD. 
 
 349 
 
 space than the modern chrome-blacks. These are rapidly completed, and look 
 well for a time, but on prolonged exposure to direct sunlight they assume an 
 unpleasant greenish hue. A logwood and copperas black upon a vatted — or, 
 as it is technically termed, woaded — bottom yields in permanence only to a 
 madder-black upon the same ground. It is not inappropriate to remark that 
 dyers have much less inducement to study fastness than was formerly the 
 case, as the rapid changes of fashion leave consumers no time to discover the 
 fugitive character of the shades. 
 
 By adding, to the logwood or its decoction, fustic,* santal wood, turmeric, 
 and alum, there are produced upon woollen fabrics, previously mordanted 
 with bichromate and cream of tartar, beautiful bronze colours, of various 
 shades. The dyeing operation is carried on at boiling heat. 
 
 Steam-blacks for wool are made up of — Extract of logwood ; a salt of 
 copper (sulphate, chromate) as oxidising material ; alum as mordant ; per- 
 nitrate of iron as mordant, and oxalic acid; sometimes bichromate of potassa 
 and sal-ammoniac are also added. 
 
 Steam-grey for wool contains — Extract of logwood ; nitro-sulphate of iron. 
 Logwood is also employed for some kinds of steam-brown and fancy colours on 
 wool. 
 
 Steam-black upon silk is produced by printing a properly thickened mixture 
 of logwood decoction, extract of nut-galls, a salt of copper, generally the 
 nitrate, and a proto-persalt of iron. Silk is dyed black by means of logwood, 
 or the decoction thereof, after having been mordanted in either sulphate of 
 iron (proto-salt), or in a mixture of that salt and nitro-sulphate of iron, or also 
 in nitrate of protoxide of iron. Silk is very frequently dyed black by a twice 
 or thrice times repeated immersion in the dye-beck, and the colour is modified, 
 if required, by the addition of fustic. If the proto-nitrate of iron is used as a 
 mordant for silk, that material, after dyeing, becomes very harsh, and its sup- 
 pleness and pliancy is therefore restored by padding in emulsified olive oil. 
 The brilliancy of black silk is often enhanced, and its weight very considerably 
 increased, by immersion in a solution of subacetate of lead, and exposure to 
 an atmosphere of sulphuretted hydrogen gas. 
 
 Logwood dyes are detected on dyed fabrics by the following tests : — 
 Logwood-black dyed tissues leave, on incineration, ash composed of peroxide 
 of iron, or a mixture of that oxide and alumina, or also, sometimes, of oxide 
 of chromium. The dyed tissues are discharged by chlorine and hypochlorites, 
 and are turned red by hydrochloric acid and tin-salt : when the reddened 
 spot, while yet moist, is pressed against white filtering-paper, it yields thereon 
 a cherry-red stain, which turns blue if touched with a glass rod moistened 
 with aluminate of soda. 
 
 The lilacs or violets produced by logwood leave, on incineration, a white 
 ash containing alumina : the dyed tissues are discharged by chlorine and 
 hypochlorites, and turn red with hydrochloric acid, presenting, further, the 
 same features as those just described for black. When the lilac or violet 
 goods are put into milk of lime, and next washed with soap, the colour is 
 discharged. 
 
 * Of this we shall say more hereafter, but it may be briefly stated to be the wood of the 
 Morus tinctoria. It is known in the trade also as Cuba wood, and largely used, especially in 
 woollen dyeing. 
 
HBHHHHHHHHHHHHHHHHHHHHBHHBHHBHHHHH8HHHHBBBM 
 
 350 
 
 DYEING AND CALICO PRINTING. 
 
 RED COLOURING MATTERS. 
 Cochineal, Kermes, Lac-lake, Gum-lac, Lac-dye. 
 The beautifully red substance known in commerce as cochineal is the dried 
 body of an insect belonging to the order Homoptera and family of Cocciche. 
 Although the discovery of the coal-tar colours has greatly diminished its con- 
 sumption as a dye-ware, it is yet largely used for the production of crimson 
 and scarlet on wool and worsted. The red dye insects inhabit various plants, 
 and are distinguished as: — Genuine cochineal or Coccus cacti; Coccus ilicis or 
 kermes ; Coccus lacca or Ficus ; Coccus ccrificus and Coccus polonicus radicens. 
 The family Coccus is divided into two groups, the one including the insects 
 not yielding any colour at all, while the other contains pigment, and these are 
 especially termed cochineal. These insects are not larger than a small pea or 
 lentil, and live upon those parts of certain plants which are exposed to air or 
 on the roots. The insects exhibit the shape of an oval shield, it being difficult 
 to distinguish their head, thorax, and abdomen with the naked eye. As a 
 rule the females remain fixed to those parts of the plants to which they fasten 
 themselves with their suckers. The male inse&s, however, move about, and 
 sometimes are even provided with wings so as to be able to fly, but they 
 are only few in number, and do not make their appearance until an advanced 
 period of the season. The females remain stationary after having laid eggs ; 
 and, dying soon after, their dried-up shell or shield serves as a shelter for 
 the eggs, whence has arisen the erroneous notion that they are viviparce. 
 The natural term of life of the insects is about a year; when fully developed 
 they appear as small hemispheres fixed by the base upon the surface of the 
 plant ; sometimes the shape is more ovoid ; their colour varies from brown 
 to red, or from violet to black. 
 
 The insect known as cochineal lives upon a species of cactus (the Cactus 
 opuntia or Nopal, or also Opuntia cocc'uiilifera), a plant which grows in a wild 
 state in Mexico, but which for the sake of the insect alluded to is cultivated 
 in gardens, being termed nopaleries. The flowers of this plant are small ; 
 the colour is red or yellow. The whole of the Cactaccce seem to be rich in 
 red colouring matter, whence has arisen the question whether the insect really 
 originates the red colouring matter, or only collects and elaborates what is 
 pre-existent in the plant. In Mexico and Central America two kinds of 
 cochineal are distinguished, viz., the Mesteque, or grana fina, home-grown or 
 fine cochineal, principally grown in the Mexican Province of Mesteque and 
 in Honduras, and the wild or forest cochineal, grana silvestra. collected from 
 the wild nopal. The former of these is more valuable than the latter, because 
 it is far richer in colouring matter. The Mexican Indians cultivate the nopal 
 plant sometimes in gardens near their dwelling houses, sometimes, also, at 
 more remote places towards the forests, where a spot is cleared by burning 
 the trees and properly tilling the soil so as to render it fit for the culture of 
 the cactus, which is reproduced from the shoots, and is fit for receiving and 
 feeding the insects after a lapse of two years. 
 
 The harvesting of the insects takes place before the setting in of the rainy 
 season, while the reproduction of the insect is secured by cutting off from the 
 nopal plant such young twigs as are covered with the young brood. These 
 are placed under shelter from the stormy weather, and kept until the return of 
 
COCHINEAL. 
 
 35* 
 
 the fine season, when the insects are brought to the nopal plantations again, 
 placed in moss. This operation takes place in the plains during the month of 
 August, and during November on the table-lands. A moderately warm 
 climate is best suited for the insects, which soon after having been placed in 
 the plantations deposit their young brood by thousands in the shape of 
 granules the size of small pins' heads. The young spread over the nopal 
 plant, and fix themselves thereon with their suckers. After the lapse of some 
 three or four months a first gathering of the Coccus takes place, just before 
 the females begin to deposit their eggs, and when a few young insects are to 
 be seen on the plants; the insects are gathered either in baskets made of 
 straw, or, better, in basins of tinned iron, and provided with a contrivance 
 suitable for embracing or enclosing the articulations of the plant, while the 
 insects are removed from the leaves by means of a soft brush. A number of 
 females are left on each plant for breeding purposes, and thus a new genera- 
 tion is produced, which is again gathered before the rainy season sets in. 
 This second gathering is effected by means of scraping off from the surface of 
 the leaves of the cactus the insects with a blunt knife ; the effect is, that not 
 only the full grown, but also only half developed insects are removed, and a 
 product obtained which, under the name of granilla, is less esteemed in com- 
 merce. The insects are killed by being immersed in boiling water for a 
 moment, and are next dried either in the sun or in ovens expressly arranged 
 for this purpose. By this treatment the peculiar white down which covers the 
 insect is lost, and its red-brown colour becomes apparent. Such kind of 
 cochineal is known as Rcncgrida. Very frequently the insects are enclosed in 
 a linen bag and killed by being placed in an oven. In this case the natural 
 grey colour is preserved, and the cochineal thus treated is known as jfaspeada. 
 The best mode of killing the insects is to expose them for a few moments to 
 the vapours of boiling water. In Mexico the insects are dried on the iron 
 plates used for baking maize cakes, an operation which imparts to the insects 
 a blackish colour, and hence it is known as Negra. The female insects which 
 die after having laid their eggs lose more weight on drying than the females 
 which are killed while with young. 4 kilos, of the first kind and 3 kilos, of 
 the latter kind yield 1 kilo, of dry cochineal. 1 hectare (2'47i English acre) 
 produces about 300 kilos, of cochineal with the labour of three men ; 140,000 
 insects produce 1 kilo, of dry cochineal. 
 
 Dried cochineal exhibits an orbicular shape ; its colour is blackish, reddish, 
 or grey; its diameter varies from 2*05 to 3 millimetres. If a few grains are 
 steeped in tepid water they swell up, assume an hemispherical shape, while 
 then, also, the peculiar form of the insect becomes distinguishable, so that the 
 body, head, the articulations where the feet are inserted, and the sucker are 
 readily visible. When the insect thus swollen up is pressed it bursts, emitting 
 thousands of very small deep red-coloured granules, presenting the appearance 
 of eggs, but viewed under the microscope these granules are recognised as 
 fully developed young brood. The Mesteque cochineal is white, covered by a 
 mealy powder, while the wild cochineal is smaller sized and enveloped with a 
 downy wool-like substance, which prevents the articulations and shape of the 
 insect from being seen. Notwithstanding all these facts, which prove the 
 animal nature of cochineal, it was for a long time considered of vegetable origin. 
 
 In the year 1592, Lopez de Gomara, and, exactly a century later, Plumier, 
 

 NUB 
 
 352 
 
 DYEING AND CALICO PRINTING. 
 
 stated that cochineal was an insect ; they even described it carefully, and also 
 the plant on which it lived. The Dutch physician and naturalist, Hartsoeker, 
 called attention to this subject in 1694, and so did De la Hire in 1704 and 
 Geoffrey in 1714 ; but no one would believe their statements, and it was not 
 until 1729 that, through the assiduous researches of Dr. Ruisch, who went on 
 purpose to Mexico, where he visited the nopaleries of Oaxaca, and published 
 a work on this subject,* that the question was settled. Mexico has for a 
 length of time been the chief cochineal-producing country, it being obtained 
 from the provinces of Tlascala and Oaxaca, as also from Guatemala and 
 Honduras, in Central America. Oaxaca alone used to yield annually some 
 400 serons. Spanish vessels used to import into Amsterdam about from 2000 to 
 3000 serons of cochineal annually, each seron containing from 130 to 200 lbs. 
 weight. 
 
 The cultivation of cochineal was practised in Mexico by the Aztecs long 
 before the conquest of the country by the Spaniards. The old Spanish 
 Government of Mexico caused the nopal plantations in Yucatan to be burnt, in 
 order to enhance the price of cochineal. It is only since 1830 that the culti- 
 vation of the nopal cactus and the cochineal insects has been spread into 
 Spain, near Malaga and Valencia, the Canary Islands, Algeria, and Java. All 
 these plantations have succeeded, but the most productive are those of Java. 
 Professor Girardin gives the following account of the different commercial 
 kinds of cochineal : — 
 
 1. Honduras cochineal is brought directly to England; it is a very superior 
 quality of cochineal, and is classified as — (a) Black or zacatilla, blackish or 
 brownish red, shiny, and bearing the traces of a whitish-coloured envelope; 
 the powder of this species is carmine-red coloured, but in water it becomes 
 deep red-brown. The value of this substance is about igs. the kilo, (b) Grey or 
 silvery-coloured cochineal ; wrapped up in a whitish mother-of-pearl-like but 
 pulverulent coating, consisting of a peculiar volatile substance, which seen 
 with a magnifying glass exhibits a very distinct crystalline appearance. In 
 the state of powder its colour is less deep than that of the foregoing, and the 
 colour of the moistened powder is less intense. The value of this kind is 
 about 17s. a kilo, (c) Reddish cochineal, only covered with a white powder 
 in the wrinkles of the body. This kind is less valuable, and does not fetch 
 more than about 15s. the kilo. All these qualities are imported either in sacks 
 covered by basket work made of cane, or in bags made of leather, and then 
 termed serons, each package weighing from 75 to 80 kilos. 
 
 2. Vera-Cruz cochineal, so named from the port of exportation. This is 
 chiefly sent to Bordeaux or Havre in serons weighing from 80 to 100 kilos. 
 The first quality is known as zacatilla ; the second as grey ; the third as reddish. 
 The insect should be hollow, light, and much shrunk. The sort which is 
 coarse grained, dull looking, mixed with small and resinous particles, is the 
 least valuable. 
 
 3. Cochineal from the Canary Islands is imported into Cadiz or Marseille. 
 It is not met with at all in large quantity, but the quality is superior even to 
 that from Mexico. It is packed either in small sacks weighing from 25 to 
 30 kilos., or in small boxes or casks. 
 
 * " Histoire Naturelle de la Cochenille," Amsterdam, 1729, in 8vo., p. 175 ; also " Philosophical 
 Transactions," xxxvi., p. 265. 
 
GUM-LAC. 
 
 353 
 
 4. Java cochineal is imported into Amsterdam and Rotterdam direct by the 
 Netherlands Society for Trade. It is packed in small tinned iron boxes 
 (square canisters), placed inside stout wooden cases, and varying in weight 
 from 40 to 60 kilos. This cochineal is reddish coloured ; its tinctorial value 
 is below that of the zacatilla kinds, but better than the wild cochineal. The 
 quantity annually brought to Europe is considerable, and it is owing to the 
 cultivation in Java that the price of this article has greatly fallen.* 
 
 Animal or Vegetable Kermes, Scarlet Grain, Oak Cochineal (Coccus 
 ilicis). — The oak kermes or green oak with prickly leaves (Qucrcus cocci/era) 
 is a tree which is found in large numbers in the South of France, Spain, 
 Italy, the Greek Islands, and in Candia. The kermes, an insed living 
 upon the leaves of this tree, is gathered by the peasantry, and is so little 
 known at present in England that when occasionally (yet rarely, and at 
 great intervals of time) a parcel of this substance arrives in London hardly 
 any of the brokers recognise it. It is more extensively used in France. No 
 colouring substance or other material used in dyeing possesses so great an 
 antiquity ; it was known in the time of Moses, and is mentioned by its 
 Hebrew name Tola. Its name, Coccus, frequently occurs in the Greek and 
 Latin writers. Kermes, like cochineal, was supposed to be berries or grains, 
 and colours dyed with them were said to be grained or engrained, and since 
 the kermes colours were fast and durable the term grained expanded in its 
 signification, and meant a fast colour whether dyed with kermes or not. But 
 kermes are insects, and the word is Arabic, signifying " little worm," and in 
 the middle ages they were called Vermiculi, and the cloth dyed with them 
 Vermiculata, whence through the French we have vermillion, a word now 
 employed as the name for one of the compounds of sulphur and mercury. 
 The term crimson is also derived from kermes through the Italian and 
 French languages. Kermes when alive on the trees is fixed to the twigs 
 either in groups or alone. It appears as if forming bluish berries, covered 
 with a whitish powder; it occurs in commerce as pale reddish brown grains, 
 which colouration is due to the vinegar used for killing them. Kermes 
 may now be considered as having merely a historical interest, and need not, 
 therefore, further occupy our attention. 
 
 Gum-lac or Resin-lac. — The substance known as gum- or stick-lac is a 
 produdt of India, 'which, when having undergone some preparations, is known 
 as lac-dye, lac-lake, or simply lac. It is derived from the Coccus lacca or 
 Ficus, an insect which lives on the young twigs of various kinds of trees, 
 more especially the Ficus rcligiosa and Indica, the Rhainnus jujuba, and 
 others. The unprepared material, stick-lac, is a kind of resinous crust 
 adhering to the twigs, and is the product of the digestive organs of a small- 
 sized insect, no bigger than a pin's head ; its body is oval shaped, somewhat 
 flattened, and composed of twelve red-coloured rings ; its antennae are half as 
 long as its body, which is at its posterior part provided with two divergent 
 hairs. These insects appear in November and December, when they walk 
 about for a short time on the twigs, and in January they fasten themselves 
 to the fleshy succulent portions of the young branches. Gradually the 
 
 * Girardin, " Traite de Chimie Appliquee," vol. ii., p. 553. Persoz, " Impression des Tissus," 
 vol. i., p. 509. Thiery de Menonville, " Traite de la Culture du Nopal, et de l'Education de la 
 Cochenille," 2 vols, in 8vo., Paris. 1787. 
 
 2 A 
 
■BE BflH BH IS I BB B BHlx !BHW 
 
 354 
 
 DYEING AND CALICO PRINTING. 
 
 abdomen of the insects becomes surrounded by a viscous transparent liquid, 
 which glues them to the plant, and which, continuing to be secreted, forms 
 a cellule surrounding the animal. The substance composing this cellule 
 is the stick-lac. The cellule attains its full size in March, and the insect 
 then exhibits the appearance of a red oval-shaped, smoothly-polished, lifeless 
 sack, entirely filled with a beautifully red liquid ; its size is then about the 
 same as the full-grown cochineal. So it remains for some months, until 
 in October the liquid will be found to contain twenty to thirty young insects. 
 The old inhabitant of the cell dies, and the young brood leave the cell by 
 piercing the top. The stick-lac when carefully viewed will be seen to contain 
 the pierced, empty, somewhat hollow cells. The young brood is so closely 
 packed together that out of a number of six only one finds room to construct 
 its cells by being enabled to pierce the twigs of the trees ; the remaining 
 insects die or are devoured by birds. The young twigs of the trees, which are 
 inhabited by the insects, appear as if dusted over with a red powder, and the 
 presence of the insect causes the death of the twigs by exhaustion. The 
 insects are carried from one tree to another by the feet of birds. 
 
 When an incision is made in the softer branches of any of the trees upon 
 which this insect lives, a milky juice exudes, which coagulates instantaneously, 
 yielding a glutinous material, which after drying resembles stick-lac. The 
 stick-lac of commerce is chiefly gathered along the hilly banks of the Ganges, 
 and in sufficient quantity to supply all demands. The stick-lac best suited 
 for dyeing purposes should exhibit a deep red colour; the pale-coloured per- 
 forated kind is only fit for varnish-making, because it does not contain the 
 insects. The stick-lac covers the branches of the trees to a thickness of some 
 millimetres, the cellules being placed longitudinally. Their diameter is 
 5 millimetres, and each contains the carcase of a dead insect. The resin 
 obtained from this material is amber-coloured, and is known as shellac. We 
 do not know whether the lac is secreted by the animal after it has been 
 modified by passing through its organs, or whether it is directly produced from 
 the vegetable parenchyma of the tree by the piercing of its bark by the insect. 
 
 In India the lac, that is to say the resin, is applied by the natives for various 
 ornamental purposes, viz., the making of bracelets, neck-chains, and the like ; 
 also as sealing-wax, and for preparing varnish. In Europe it is used for 
 dyeing and varnish. 
 
 Shellac, the main constituent of our sealing-wax, is, as already noticed, 
 produced by the insect, but the shape it is met with in trade is due to artificial 
 preparation.* The tree known as Celastrus ceriferus, a native of India and 
 the warmer part of China, and producing a wax largely used in these countries 
 for candle-making, supports an insect of the same kind known as Coccus 
 ceriferus. The Chinese cultivate this insect, and it yields a waxy red-coloured 
 substance, known as pela.t Of stick-lac the following varieties occur: — 
 
 i. Stick-lac in sticks gathered in March and October. The cellules are 
 fastened to the twigs upon which they were formed. It is a hard, dark red, 
 transparent resin, which shines when broken ; if chewed it colours the saliva 
 
 * Kerr, " Phil. Transactions," lxxi., 1781, p. 374, Figs. 1 to 6 
 tions," lxxxi., p. 228. " Asiatic Researches," ii., 1799, p. 361 
 du Didt. des Sc. Med.," x., 1821, 193, Figs. 1 to 7. 
 
 1 "Anderson, " Monographia Cocci Ceriferi," 1791. Pearson, in 
 1794, p. 383. 
 
 Kerr, " Roxburgh Transac- 
 Virey, "Journal Complem 
 
 ' Phil. Transactions, 
 
LAC DYE. 
 
 355 
 
 violet, its taste being astringent and bitter. It is insoluble in water, to which 
 it, however, imparts its colouring matter, rendering it red. It is partly soluble 
 in alcohol, yielding a red solution, but it is insoluble in fatty and essential 
 oils. Its composition is, according to Hatchett — Resin, 68; colouring 
 matter, 10; wax, 6 ; gluten, 5-5; foreign matters, 10-5. Dilute sulphuric and 
 hydrochloric acids are better solvents for the colouring matter than water, 
 whence they are applied in the lac-dyeing process. '1 he best kind of this 
 variety of stick-lac is imported from Siam, the Bengal product being very 
 inferior. 
 
 2. Grained lac consists of the cells detached from the wood of the branches. 
 It occurs in small, variously-shaped, broken-up pieces, and, as met with in trade, 
 is frequently robbed of a portion of its colouring matter by treatment with 
 water. It consists of — Resin, 88 - 5 ; colour, 2*5 ; wax, 4/5 ; gluten, 2 - o ; woody 
 fibre, sand, &c, 2. 
 
 3. Lac in the shape of cakes is simply the material just mentioned after 
 having been fused and cast into moulds. 
 
 4. Lac in the shape of thin scales is obtained in the following manner: — 
 The crusty resinous substance is pulled from the branches of the trees, broken 
 into small fragments, macerated for twenty-four hours in cold water, washed, 
 dried, and put into a bag made of stout calico, which is tied at the mouth, 
 and placed over a clear charcoal fire. The resin liquefies, and on pressure 
 being applied the molten material runs in thin layers over a plank of polished 
 fig-tree wood, when it soon solidifies. This material goes by the name 
 of shellac, and contains gi per cent of resin, only about i percent of colouring 
 matter, while the rest is wax, gum, and other substances. 
 
 Lac-lake and lac-dye are the secondary- or by-products of the process just 
 described, carried on with the following modification: — The crude matter as 
 taken from the trees is coarsely powdered and exhausted by maceration in hot 
 water, to which sometimes a little soda is added. The liquid thus obtained, 
 sometimes after previous filtration through coarse canvas, is evaporated in 
 pans placed on a charcoal fire, or left to spontaneous evaporation by the sun's 
 rays in shallow earthenware vessels. The dry residue is in the shape of 
 square cakes, 36 millimetres by 13. This material consists on an average of— 
 Resin, 25 ; colouring matter, 50 ; earthy impurities, 22. It is shipped from 
 Calcutta, and is chiefly brought to London and Hamburg. This substance 
 has been known and prepared in India for centuries ; its English name was 
 given to it by Mr. Stephens, who at the end of the last century made it known 
 in Europe. 
 
 Although the colouring matter of lac-dye is analogous to that of cochineal, 
 its identity is not established, the shades produced being less bright but more 
 permanent. The richness of this and similar products in colouring matter is 
 determined in the same manner as has been stated for cochineal, viz., by a 
 dyeing process on the small scale. The lac-lake is obtained by precipitating 
 with alum the decoction of stick-lac prepared with weak caustic soda. The 
 ensuing deposit is pressed, moulded into cakes, and dried. It consists of — 
 Colouring matter, 50; resin, 40; alumina, 9; impurities, 1. For dyeing it is 
 best first decomposed by weak hydrochloric or sulphuric acids. There are met 
 with in commerce a great number of brands of lac-lake and lac-dye, but the 
 trade-mark is r.o guarantee of the quality. 
 
 2 a 2 
 
&$5&£^^ 
 
 ViA'iiUi 
 
 356 
 
 DYEING AND CALICO PRINTING. 
 
 Messrs. Brooke, Simpson, and Spiller have introduced into commerce a 
 lac-dye superior to that imported from India. Their improvement consists in 
 treating stick-lac with weak ammonia, and adding to this solution chloride of 
 tin, when a fine red insoluble matter is formed, and precipitates. This is 
 collected, and is ready for use. These different preparations are chiefly applied 
 for dyeing woollen fabrics scarlet ; 2 to 3 parts produce the same effect as 
 1 part of cochineal. In order to neutralise the influence of the alumina, a 
 larger proportion of tin solution is required to be added to the acidified dye- 
 liquor. 
 
 The India Museum (India Office, Westminster), contains a very complete 
 and valuable collection of all the substances here described, and also of various 
 products which are never met with in the European trade, belonging to this 
 class of materials. 
 
 What is, or at least was, known as Polish grain, Coccus polonicus, or Polish 
 kermes, is an insect living on the roots of the Sclcranthus, a plant growing 
 wild, in various parts of Central Europe, in a sandy soil. This insect — of the 
 size of a peppercorn, exhibiting a purplish-red colour — was formerly gathered 
 about the middle of June, but now it is altogether forgotten, having been dis- 
 placed by cochineal. 
 
 As far as the colouring matters of genuine cochineal and stick-lac have been 
 investigated, it appears that, if not identical, they at least agree closely in 
 their properties. Cochineal owes its tinctorial properties to a red acid, soluble 
 in water. Within the body of the living insect the colouring matter is present, 
 not in the state of solution, but as small granules grouped around a larger 
 colourless nucleus, in state of suspension, in the midst of a colourless liquid. 
 The insect is richest in this substance just before the period of laying eggs. 
 This acid, though in an impure state, was first isolated by MM. Pelletier and 
 Caventon, who called it carmine, considered it to be a nitrogenous matter, and 
 expressed its formula by C8H I3 N0 5 . Arppe, Warren de la Rue, and Hugo 
 Miiller proved it to be an acid, and found that in a perfectly pure state it does 
 not contain any nitrogen, though it is accompanied by nitrogenous matters, 
 which render its purification very difficult. According to the authors just 
 named, the pure substance in the amorphous state consists of C I4 H I4 08. 
 Carminic acid in crystals, as obtained by Dr. Schiitzenberger, consists of 
 C 9 H80 5 ; but Dr. Schaller, who also obtained this acid in a crystalline state, 
 represents this composition as C g Hs06. Dr. Schiitzenberger found, more- 
 over, that the colouring matter exists in cochineal in two degrees of oxidation ; 
 to one of these the formula CgHs0 5 belongs, and to the other C 9 Hs0 7 , 
 Schaller's formula being intermediate. Schiitzenberger, however, desires that 
 these researches should be taken up by some one, in order to settle this point 
 definitively. 
 
 Carminic acid may be obtained readily in the crystalline state by the fol- 
 lowing process : — Cochineal is exhausted first with ether, which removes fatty 
 matters, and next with boiling water. The red liquid is precipitated with neutral 
 acetate of lead, slightly acidified with acetic acid. The bluish-violet precipi- 
 tate which falls carries down all the colouring matter, and the filtrate is nearly 
 colourless. When well washed with hot water the precipitate consists chiefly 
 of carminate and phosphate of lead, mixed with a small quantity of nitro- 
 genous matter, a larger portion of which is found in the filtrate, which, on 
 
CARMINIC ACID. 
 
 357 
 
 being evaporated to a syrup, yields tyrosine in crystals. The plumbic precipi- 
 tate is suspended in water, and decomposed by sulphuric acid, taken in 
 sufficient quantity to effect the conversion of the whole of the lead-salts 
 present into sulphate. The liquid is filtered while hot, and the carminic acid 
 thus set free is dissolved in the filtrate, while the phosphoric acid remains 
 with the residue upon the filter. The filtrate is evaporated to dryness, at 50 , 
 on a water-bath, and the dry residue is taken up by absolute alcohol. When 
 the partly evaporated alcoholic solution is cooled, the carminic acid is obtained 
 in a crystallised state, exhibiting a somewhat red, cauliflower-like, appearance. 
 The crystallised mass contains frequently, however, yellow hexagonal-shaped 
 crystals, which may be separated by treatment with cold water, wherein these 
 crystals are insoluble. The filtrate, again evaporated, is either again taken 
 up by absolute alcohol or by ether, because, although the carminic acid is 
 sparingly soluble in that liquid, it yet yields the cauliflower-like shaped mass. 
 Pelletier and Caventon prepared their carmine (an impure carminic acid) by 
 exhausting the cochineal, previously treated with ether, with boiling alcohol. 
 This solution, when concentrated, yielded a semi-crystalline precipitate, 
 which, when again dissolved in alcohol, gave, on the addition of its own bulk 
 of ether, a precipitate of carmine. The product thus obtained appears to be 
 a compound of carminic acid and a nitrogenous substance (tyrosine ?) 
 
 Pure carminic acid is a solid, purplish-red substance, which, when reduced 
 to a very finely-divided powder, is bright red ; it crystallises, as already ob- 
 served, from its alcoholic solution, tastes decidedly acid, is very soluble in 
 water and alcohol, but hardly soluble in ether. It may be heated to 136 
 without decomposition. It dissolves, without decomposition, in strong sul- 
 phuric and hydrochloric acids ; the haloids readily and rapidly destroy it. 
 Nitric acid of sp. gr. 1-4 converts it into oxalic and nitrococcussic acid, while 
 red vapours are given off. Nitrococcussic acid is a nitrated compound, forming 
 yellow-coloured foliated crystals, of the formula CsH^NOa^CXj-f-HaO. The 
 aqueous solution of pure carminic acid is not spoiled by contad with air; 
 caustic alkalies colour it purplish-blue ; with lime and baryta water purplish- 
 blue precipitates are thrown down ; the acetates of lead, zinc, copper, and 
 silver yield purplish precipitates. The argentic precipitate is readily decom- 
 posed, metallic silver being set free. Alum does not cause a precipitate in 
 this aqueous solution unless some ammonia be next added, when a carmine 
 lake is thrown down. Hydrate of alumina immediately withdraws carminic 
 acid from its solutions ; the ensuing compound remains red as long as heat is 
 not applied, but if heated becomes first carmine-red and next violet. The 
 same effedt is produced by the addition of a drop of any acid, or a small 
 quantity of any solution of a salt of alumina, while alkalies, on the other 
 hand, give stability to the red colour. The neutral alkaline salts turn carminic 
 acid to violet, while the acid salts of alkalies (bitartrate of potassa, for instance) 
 render the shade more orange. Neutral salts of lime, baryta, and strontia 
 give a violet colouration to the aqueous solution ; sulphate of lime produces a 
 precipitate. 
 
 The chemical history of the carminates is as yet very far from complete. 
 The alkaline carminates are soluble ; the others are, as far as ascertained, 
 amorphous, pulverulent substances. Carminate of soda, in the shape of 
 purplish-coloured foliated crystals, may be obtained by cautiously adding 
 

 358 
 
 DYEING AND CALICO PRINTING. 
 
 alcohol to an aqueous solution of that salt. According to Schaller, carminate 
 of soda may be obtained in crystals from its aqueous solution ; its formula is 
 
 \r 8 4 |- 2 . Nascent hydrogen reduces solutions of carminic acid, but the 
 
 red colour returns on contact with air. 
 
 The decoctions of cochineal behave, to some extent, different!}' with re- 
 agents, this difference being due to the presence of nitrogenous substances 
 and phosphates. The following are the characteristic reactions of a decoction 
 of cochineal : — Acids turn the colour to a yellowish-red, the fieriest shade 
 being produced by oxalic acid, and cause a slight precipitate ; alkalies turn 
 the colour violet ; lime-water gives a violet-coloured precipitate ; alum turns 
 the colour first red, and then gives a precipitate ; chloride of aluminium, 
 reddish-vioiet precipitate, the supernatant liquid being amaranth-coloured ; 
 chloride of tin turns the colour yellowish, forming a cherry-red precipitate ; 
 chloride of tin (as usually met with in the trade), violet precipitate ; bichloride 
 of tin turns the colour to scarlet ; sulphate of iron gives first a violet-grey, 
 and next a precipitate ; acetate of iron, a brown-coloured precipitate, turning 
 to olive ; sulphate of copper and lead salts, violet-coloured precipitates ; 
 proto-nitrate of mercury, a precipitate exhibiting the colour of dregs of wine; 
 per-nitrate of mercury, a brownish-red precipitate ; sulphate of zinc, deep 
 violet precipitate ; cream of tartar, salt of sorrel, and alum, yield each red 
 precipitates ; constituting the carmine of commerce. 
 
 Ammoniacal Cochineal. — When a solution of carminic acid in ammonia 
 is for some time left to itself a modification takes place, whereby the acid 
 combines intimately with the elements of ammonia, there being formed an 
 amide or an amidated acid : this fact, long since known, has been utilised for 
 the preparation of a new colouring matter, termed ammoniacal cochineal, or 
 carminamide. This colouring matter does not produce red and scarlet 
 colours, but violets, amaranths, and mauves, and the action even of oxalic 
 acid in excess does not turn the colour of this pigment to yellowish-red. 
 With bichloride of tin a deep violet, not a scarlet, precipitate is formed. 
 There are met with in commerce two different kinds of ammoniacal cochineal, 
 in cakes and in paste ; the former is prepared by digesting for three months, 
 in a closed vessel, 3 parts of ammonia and 1 part of ground cochineal. The 
 liquor is decanted, and then is added to four-tenths of its weight of gelatinous 
 alumina. This magma is evaporated in a copper basin, so as to expel all 
 ammoniacal smell, when the thickish mass is cut up into the shape of cakes, 
 and dried. The paste is prepared in a similar manner, but the operation only 
 lasts eight days ; the liquor is evaporated to two-thirds of its bulk, and no 
 alumina is added : this paste is one-third less rich in colouring matter. Dr. 
 Schiitzenberger states that the colouring matter of the ammoniacal cochineal 
 of commerce, and also that obtained by the direct action of ammonia upon 
 carminic acid, contains nitrogen in another form than that of an ammoniacal 
 salt ; and the formula of this compound is CgH 9 N0 4 . 
 
 The substance known as carmine is a preparation of cochineal, exhibiting a 
 very bright red colour ; it is met with in commerce as an almost impalpable 
 powder, or as cakes packed in thin glazed paper or in small boxes ; it is also 
 sold mixed up with white of egg, gelatin, or isinglass solution : the value of 
 this substance depends upon various causes, but its beauty and the fineness of 
 
CARMINE. 
 
 359 
 
 powder are the chief points which determine its price, and the purer the 
 material the better are its qualities. 
 
 Pure carmine is entirely soluble in ammonia, and upon that property its 
 use in the dyeing of tissues is based. The true nature of the combination of 
 carminic acid which forms this compound is unknown ; in its formation the 
 intervention of the nitrogenised matters naturally present in cochineal, or of 
 those which can be added to a solution of carminic acid, is required. The 
 preparation of carmine itself is not a matter which is very well known ; every 
 maker keeps secret that method which yields him the most beautiful and 
 remunerative product. According to Prof. Girardin, the manufacture was 
 accidentally discovered, at Pisa, by a Franciscan monk, who, while experi- 
 menting with cochineal and carbonate of potassa, observed, on adding an acid 
 to that mixture, the precipitation of a beautifully red-coloured substance. 
 Dr. Homberg published, in 1656, a method for the preparation of carmine. 
 Generally speaking carmine is prepared by exhausting previously pulverised 
 cochineal with boiling water, to which sometimes an alkaline salt is added ; 
 and the precipitation of carmine is effected either by a weak acid or an acid 
 salt. Sometimes albumen or gelatin is added to the liquid, and also alum. 
 
 The following prescriptions are practical, and give an idea of the method of 
 preparation of this colouring matter: — Take J kilo, of powdered cochineal, 
 boil with 10 litres of water for a quarter of an hour, add 30 grms. of alum, 
 boil up for three minutes, let settle ; the clear liquid carefully decanted will 
 deposit, on standing for a few days, from 40 to 50 grms. of carmine ; the clear 
 decanted liquid deposits, after some few days longer rest, another but smaller 
 quantity of carmine of inferior shade. Or, take 1 lb. of powdered cochineal, 
 30 lbs. of water, boil for a quarter of an hour, add 30 grms. of best cream of 
 tartar, boil for ten minutes longer, then add 15 grms. of alum, and boil up for 
 a couple of minutes ; the clear and decanted liquid is left to deposit in shallow 
 glass vessels ; the carmine is washed with cold distilled water, and dried care- 
 fully in the shade. 
 
 The following is the prescription of Madame Cenette, a lady once in very 
 extensive business in carmine making) : — Take 2 lbs. of ground cochineal 
 and 150 lbs. of water, boil for two hours ; add 3 ozs. of pure nitrate of 
 potassa, boil for three minutes longer ; add next 4 ozs. of salt of sorrel, 
 boil again for ten minutes ; after the liquid has become clear, by standing for 
 a quarter of an hour, it is set aside in shallow glass vessels for three weeks, 
 after which time the carmine which has deposited is carefully separated from 
 the liquid, which, meanwhile, has grown mouldy on the top; the carmine is 
 dried in the shade. 
 
 The carmine of commerce is often adulterated with starch, kaolin, French 
 chalk, vermillion, and sometimes contains small bits of cochineal. Since pure 
 carmine is readily and entirely soluble in ammonia, such adulterations are 
 readily detected. 
 
 Carmine is chiefly used by artists in oil and water colours, for the colouring 
 of superior bonbons, artificial flowers, and, in rare cases, the printing of 
 tissues. Carmine is chiefly made in Germany, whence it is exported into 
 other countries. France obtains annually about 400 kilos, of superior, and 
 3500 kilos, of common, carmine from Germany. Carmine of the highest 
 quality, it should be here observed, can only be prepared under certain peculiar 
 

 360 
 
 DYEING AND CALICO PRINTING. 
 
 conditions of the atmosphere and daylight, but nothing quite definite is known 
 in this respect. 
 
 Carmine-lake is a substance of a beautiful red colour, and is obtained by 
 the addition of an alkali to a decoction of cochineal mixed with alum. This 
 substance was known before cochineal was discovered, and was made at 
 Florence from kermes, — hence the name of Florentine lake, still in use. 
 Cochineal is also met with in commerce in the state of cake. Although very 
 rarely thus brought to Europe, a parcel reached France some years ago from 
 Cordova, in South America : it was in the shape of solid, round, shiny, deep 
 red-coloured cakes, containing five-sixths of the ordinary colouring matter of 
 cochineal ; the rest consisting of broken-up pieces of the insect (Coccus Cacti) 
 mixed with vegetable matter. 
 
 Without being in the least adulterated, cochineal differs in richness of 
 colouring matter, according to its origin. Sometimes parcels reach the 
 European market which have been partly exhausted with boiling water and 
 re-dried : this fraud is always accompanied by the loss of the naturally- 
 adhering down of the insect, and in order to reproduce the appearance thereof 
 the inse&s are, before, being quite dry, placed in casks along with some white 
 powder or other, — as, for instance, white lead, sulphate of baryta, or French 
 chalk. In order to detect this sophistication it is only requisite to place the 
 cochineal in cold water for some time, when such adhering powders will 
 become detached, sink to the bottom of the vessel, and may be analysed after 
 decantation of the water. Partly exhausted cochineal is always more deeply 
 wrinkled, and does not, when placed in water, take up moisture equally; a 
 portion of the insects (grains, as they are termed by the brokers) float, and 
 others become only partly submerged. Various methods have been proposed 
 for determining the richness of cochineal in colouring matter. M. Robiquet 
 does this comparatively in the following manner : — One part by weight of 
 cochineal is five times successively exhausted with water, and the solutions 
 obtained are decolourised by a solution of 10 parts of bleaching-powder : this 
 method is obviously faulty, for the good reason that the decoction of cochineal 
 contains other organic matters beside the colouring material, and the oxidising 
 action of the hypochlorite of lime is partly expended upon these substances. 
 By Anthon's method a known volume of a solution of alum is applied to pre- 
 cipitate completely a decoction of cochineal, and a standard sample of that 
 ware is used for comparing the results. Penny's method is based upon the 
 ready oxidation of the colouring matter of cochineal (carminic acid) by the 
 red prussiafe of potassium (ferricyanide) in the presence of an alkali ; 1 grm. 
 of pulverised cochineal is dissolved in 36 grms. of a weak solution of caustic 
 potassa ; this solution is diluted with 24 grms. of water, and there is next 
 added by drops a standard solution of ferricyanide of potassium, containing 
 5 grms. of that salt to the litre of water, until the purplish-red colour of the 
 original solution be converted into a brownish-yellow. 
 
 Since carminic acid is completely precipitated by neutral acetate of lead, 
 M. Bloch proposes the use of a standard solution of that salt for estimating 
 quantitatively the acid alluded to ; unfortunately the reagent proposed precipi- 
 tates a variety of other substances likewise. 
 
 Those who apply cochineal for dyeing test its goodness by a dyeing process, 
 executed on the small scale, as for madder, taking 1 grm. of the ware ; or they 
 
COCHINEAL. 
 
 361 
 
 print upon a woollen fabric a colour prepared with a known weight of pul- 
 verised cochineal : in both cases standard samples of the ware are applied for 
 the sake of comparison. This method, however good, will give erroneous 
 results if the cochineal is mixed with Brazil wood ; but this sophistication 
 may be dete&ed, according to M. Persoz, by the following simple test : — 
 When lime-water (not milk of lime) is added to a dilute solution (decoction) of 
 cochineal the colour is discharged forthwith, but if Brazil wood is present 
 along with the cochineal a violet tinge remains. When a piece of calico is 
 impregnated with a decoction thus adulterated, and next steeped in a tepid 
 solution of bichromate of potassa, the tissue will assume a rather deep colour, 
 Cochineal is sometimes mixed with artificially-moulded insects, made up of 
 some coloured paste ; but this fraud is readily detected, even by steeping the 
 suspected substance in water, which has the effect of disintegrating the 
 moulded material, and making it crumble to pieces. 
 
 In the selection of cochineal considerable caution is needed. The grains 
 should be full, plump, dark, and glossy. Silvery kinds and samples of a 
 reddish-grey mottled appearance are not to be trusted, as the former are often 
 weighted, and the latter immature and deficient both in the quantity and 
 quality of their colouring matter. Gritty samples, in which small stones, 
 clay, and sand are perceived, should be rejected. The specific gravity is an 
 important characteristic, and may often be taken when there is not time to 
 dye swatches, or to try the amount of colouring matter by any chemical pro- 
 cedure. We may at least lay down the rule, that though a light sample may 
 be bad, yet a heavy one cannot be good. The specific gravity varies so much 
 that of samples dried at 212 F. the superior kinds weighed 60 to 66 grs., 
 whilst the same measure of the inferior qualities weighed 80, 90, and 
 even 100. A Rham's specific-gravity bottle, or, in default, a very small 
 li^ht beaker, will answer the purpose. The vessel is accurately tared, 
 and then filled exactiy full of the cochineal, not by pressing, but by gentle 
 tapping and shaking. If the same vessel is always used the results will be 
 comparable. 
 
 A good lac-dye should be soft enough to be broken by the fingers. The 
 fradture should be deep in colour, but should not appear shining and resinous, 
 and should, when breathed upon, give out a strong and peculiar odour. If the 
 lac is hard and has a resinous fradture, it is poor in colour and rich in shellac. 
 It should pulverise easily under the pestle. Excess of resin is especially 
 objectionable if the lac is intended for dyeing worsted goods which have to be 
 hot-pressed. If it is loaded with resinous matter the pressing-paper will stick 
 to the surface in patches, and can only be removed at a great outlay of time 
 and labour, if at all. To ascertain roughly the amounts of resin, equal weights 
 of the samples, in powder, are placed in small flasks, with the addition of 
 equal measures of alcohol, and they are set to digest in a warm place, loosely 
 stoppered, and occasionally shaken. The alcoholic solutions are then allowed 
 to settle in the cold, decanted off into light capsules, previously tared, evapo- 
 rated to dryness, and weighed. Or excess of water may be added to the alco- 
 holic extradts, when the shellac will be precipitated, and its comparative 
 amount may be judged by the eye with sufficient accuracy. 
 
 Cochineal is employed in dyeing and printing in the following states : — As 
 met with in trade, without having undergone any preparation at all ; ground 
 
mmnmuumm pm hbb 
 
 362 
 
 DYEING AND CALICO PRINTING. 
 
 up to a more or less fine powder; in the state of decoction, made either with 
 water only or with that fluid acidulated or rendered alkaline. 
 
 Carminic acid, although soluble in water, does not fix itself to any kind of 
 fibre, whether animal or vegetable : it dyes cotton, mordanted with alumina 
 only, amaranth-red, but when oxide of tin is simultaneously present as 
 mordant a flat and meagre scarlet-red is produced ; with iron mordants the 
 colours produced are grey, violet-grey, or greyish-black, according to the 
 strength. 
 
 Wool mordanted with preparations of tin is dyed a brilliant scarlet, of a 
 peculiarly bright hue, and not readily obtainable by any other dye ware or 
 upon any other fibre. The lac-dye of Messrs. Brooke, Simpson, and Spiller 
 yields, upon wool, a colour almost as bright and beautiful. 
 
 Amaranth-red, red, violet-red, scarlet, and red-purple are produced by 
 cochineal in its entire or ground-up state. Ammoniacal cochineal is used for 
 mauve and amaranth-purple, and is ; moreover, an ingredient of some compo- 
 site colours. The dyeing of mordanted cotton, and all the operations 
 pertaining thereto, are for cochineal the same as for madder. 
 
 Since carminic acid is rather a strong one, it has the power of dissolving 
 temporarily some of the aluminous mordant, if too much of the ware is 
 present along with the mordanted tissue : this would tend to weaken the colour 
 intended to be obtained, and, moreover, the lake thus set free in the dye-beck 
 might become fixed upon portions of the tissue intended to remain white; for 
 this reason the cochineal is either added in two portions to the dye-bath, or 
 the cloth is dyed first in a partly-exhausted bath, to which next a fresh portion 
 of cochineal is added. The temperature of the first bath is only 40 ; the second 
 is brought to boiling ; the addition of some nut-galls to the bath is intended to 
 give fastness to the colour, as well as to prevent the corroding action of the 
 carminic acid. Probably an excess of carminic acid forms a soluble acid 
 carminate, which during the dyeing process is rendered neutral and insoluble, 
 and thus fixed upon the white portions of the tissue. The goods, on being 
 taken from the dye-beck, are so slightly soiled that after a thorough rinsing in 
 water and a bran-bath the white is perfectly restored. The colours thus ob- 
 tained are not fast, and do not stand washing with soap nor the action of 
 either acids or alkalies. 
 
 Cochineal is very rarely, if ever, at all applied to mordanted cotton or calico 
 tissues since the introduction of aniline colours ; but its use as a steam- 
 colour upon cotton, and in dyeing and printing wool and silk tissues, is very 
 extensive. 
 
 Deep Rose-Red for Steam-Colour. — 1 litre of a decoction of cochineal made 
 with 250 grms. of the grain to the litre; 2 litres of water; 0-5 litre of red 
 liquor, at io° B. (sp. gr. i"075) ; 40 grms. oxalic acid ; 175 kilos, gum. 
 
 Application-Red. — 2 litres of a decoction of cochineal made with 375 grms. 
 to the litre ; 25 grms. tragacanth gum ; 185 grms. pink salt, prepared with 
 1 litre of nitro-muriate of tin mixed with a hot and saturated solution of 
 500 grms. of sal-ammoniac. 
 
 Cochineal-lake is employed for the purpose of printing, being fixed by means 
 of albumen. Cochineal is fixed upon wool and silk by means of alum and 
 cream of tartar, whereby carmine shades are obtained ; for scarlet, tin crys- 
 tals are added. 
 
COCHINEAL. 
 
 3°3 
 
 The following are the shades obtainable by means of cochineal and ammo- 
 niacal cochineal upon wool : — 
 
 1. Groseille* (bright). — For 10 kilos, of wool : 1 kilo, of cream of tartar and 
 
 2 litres tin solution, made up of 8 litres water, 400 grms. common salt, 
 1-25 kilos, tin, to which is gradually added 8 litres nitric acid. The 
 wool is kept in this mixture, at boiling heat, for an hour, and is next 
 dyed with ammoniacal cochineal for bright shades, in ammoniacal 
 cochineal mixed with raw cochineal and some orchil for medium shades. 
 
 2. Violet Groseille. — Mordant as above, and dye with ammoniacal cochineal 
 
 for clear as well as medium tints. 
 
 3. Amaranth-Red. — The same mordant ; dye with raw cochineal and orchil 
 
 for clear, bright, and medium tints ; the quantity of orchil has to be 
 increased for the latter. Deep shades are produced by the use of raw 
 cochineal with orchil and sulphate of indigo. 
 
 4. Redj is produced by the same process and ingredients as No. 3, only 
 
 taken in varied quantity. 
 
 5. Vermillion. — Mordanting and dyeing are done simultaneously. For 
 
 1 kilo, of wool 0*25 litre of the mordant for red is taken, and powdered 
 cochineal, the dye-bath being heated to boiling. 
 
 6. Rose-colour. — Mordant as for No. 1, dyeing with ammoniacal cochineal. 
 
 7. Bright Amaranth-Red. — Same mordant ; dye, at boiling heat, with raw 
 
 cochineal, ammoniacal cochineal, orchil, and for deeper shades some 
 sulphate of indigo. 
 
 8. Violet Amaranth-Red is produced by the same means, only the quantities 
 
 are somewhat varied. 
 
 9. Purple is produced with the same mordant, the raw cochineal being 
 
 applied at boiling heat. 
 10. Cherry -Red shades are produced by the same means, simply varying the 
 quantities of materials. 
 
 The following may serve as examples for steam-colours upon wool : — 
 
 Rose-Reds. — (a). 16 litres of a decoction of ammoniacal cochineal (made up 
 of 6 kilos, of ammoniacal cochineal, 2 kilos, acetic acid, and 12 litres of water, 
 to be boiled together) ; alum, 1-5 kilos. ; oxalic acid, 700 grms. ; tartaric acid, 
 700 grms. ; bichloride of tin, 1*5 kilos. ; thickened with gum Senegal. 
 (b). 500 grms. of ground cochineal, to be boiled with water, 12 litres to 9 litres ; 
 gum, 2 - 937 kilos. ; oxalic acid, 500 grms. ; bichloride of tin solution, at 
 55 Baume (sp. gr. i - 6i8), 600 grms. 
 
 Ponceau Red. — 2 litres of a decodtion of cochineal containing 250 grms. to 
 the litre ; starch, 300 grms. ; oxalic acid, 120 grms. ; tin solution, 120 grms., 
 made up with 1 kilo, of nitric acid, 2 kilos, of hydrochloric acid, and 360 grms. 
 tin ; 60 grms. of bichloride of tin. 
 
 Same colour, but different shade : — 4 litres of deco&ion of cochineal con- 
 taining 500 grms. to the litre ; 3 kilos, gum ; 350 grms. oxalic acid ; 500 grms. 
 of bichloride of tin solution (sp. gr. r6i8). 
 
 Amaranth-Red. — Exhaust 500 grms. of ammoniacal cochineal with pure 
 water, evaporate to 2 litres, filter (or pass through a fine silken sieve) ; add 
 
 * Since, technically, that word is in use in all languages to indicate that peculiar red exhi- 
 bited by ripe red gooseberries, we retain it here also. 
 
 t Differs from that obtained by madder, but is a true red. 
 

 364 
 
 DYEING AND CALICO PRINTING. 
 
 gum, 600 grms. ; alum, 60 grms. ; oxalic acid, 60 grms. — to this latter some- 
 times a little bichloride of tin is added. 
 
 Ammoniacal cochineal, mixed with various other substances, enters into the 
 compositions used for some colours ; for instance, with orchil, alum, and 
 oxalic acid, in proper proportions, pomegranate-red is produced. With carmine 
 of indigo, alum, and oxalic acid, violet is obtained. 
 
 The cochineal colours, especially upon cotton, are fugitive, and do not wear 
 well. They are affected by washing, acids, or alkalies ; soap suds and weak 
 alkalies, lime-water, turn the colour to a violet-blue. They are also damaged 
 by perspiration. 
 
 Silk t is dyed carmine with cochineal by the following process: — (1), mor- 
 danting in a bath composed of 20 parts of water and J kilo, of bichloride of 
 Lin ; (2), dyeing in a clear bath of cochineal, at a temperature of from 30° to 
 40 , the fabric being worked for about three hours : the shade may be improved 
 by an addition of ammoniacal cochineal. For scarlet the silk is previously 
 dyed yellow, with annatto. Silk is dyed ponceau by placing it in a bath pre- 
 pared with 10 kilos, of ammoniacal cochineal dissolved in ten times its weight 
 of water: this mixture is boiled for about ten minutes, and there is added to 
 it, after that, i kilo, tin crystals, 1 kilo, of cream of tartar, 2i kilos, of sul- 
 phuric acid, and 2 kilos, tin compound (viz., % kilo, tin, 1 kilo, hydrochloric 
 acid, and 1 kilo, nitric acid) : the whole mixture is boiled for an hour, decanted 
 after cooling, and, after the addition of 3 kilos, of safflower, the silk is 
 immersed in the liquid. 
 
 Harmala-Red. 
 
 The Syrian rue, known botanically as Peganum Harmala, is a plant growing 
 plentifully in Western Asia and in the South of Russia. From its seeds is 
 extracted a tinctorial principle known as Harmala-red. It is obtained by 
 steeping the seeds of the plant in alcohol for from eight to fourteen days. 
 The colour has basic properties ; it is insoluble in water, but soluble in ether, 
 and dissolves very readily in absolute alcohol. It combines with acids, 
 forming red salts. Harmala-red dyes up a variety of shades upon wool 
 sind silk, from a bright rose to a full scarlet. The most suitable mordants 
 appear to be the acetate and the sulphate of alumina. The harmala colours 
 are not very fast. In the seeds of the Syrian rue there are also found 
 harmaline and harmine, two alkaloids, soluble in acidulated water. They 
 have been examined by several chemists, but have no tinctorial interest. 
 
 Erythrose. 
 Erythrose, or erythrosic acid, is the name given to a tinctorial substance 
 prepared from the roots of rhubarb, as well the medicinal as the common 
 kind. It is prepared by digesting the roots, previously cleaned, dried, and 
 sliced, with 4 parts of nitric acid. The residue, which amounts to 8 to 10 per 
 cent, dissolves in alkalies with red and purple colours. With the tin and 
 aluminous mordants, erythrose may be made to yield pleasing shades, but it 
 has never been brought into the market, and, since the discovery of the 
 aniline colours, has been altogether lost sight of. Powdered rhubarb-root, 
 rubbed up with an essential oil (bergamot, aniseed, or fennel) and magnesia, 
 takes a bright rose-colour — a reaction which deserves to be further investigated. 
 
MADDER LAKE. 
 
 365 
 
 Fustic-Carmine. 
 
 From fustic, yellow wood, or Cuba wood, — a dye-ware which will be more 
 particularly noticed below, when we come to treat of yellow colouring matters, 
 — a red dye may be prepared which is known as fustic-carmine. It is obtained 
 as follows : — The extract of fustic is allowed to stand until the morine-lime is 
 deposited, when the clear liquid is evaporated to dryness. The residue i3 
 finely powdered, and rubbed in a mortar with strong sulphuric acid. From 
 the brown-yellow solution a brick-red mass separates, which gives a splendid 
 carmine solution with a little ammonia or soda. It yields, with alum and a 
 little alkali, a red precipitate ; with protochloride of tin and chloride oi 
 barium, a red precipitate ; and with nitrate of lead, a cherry-red. 
 
 This colour may be worth a closer examination than it has yet received. 
 The raw material for its preparation may also be found by taking the deposit 
 which is found on splitting blocks of fustic, and purifying it by repeated 
 solution in boiling water, and crystallising. It is then dissolved in more 
 boiling water with a little hydrochloric acid, and filtered. The clear liquor is 
 set aside till a yellow powder subsides, which is then treated with sulphuric 
 acid, as above. 
 
 PREPARATION OF LAKE COLOURS. 
 
 The increasing attention paid to the pigment-style in printing makes it 
 necessary for us to give a brief account of the preparation of lake colours. 
 
 A. Red Lakes. 
 
 1. Madder-Lake. — The following is a receipt for which the Society of 
 Arts awarded their gold medal to Sir H. Englefield, the inventor: — 2 ozs. troy 
 of the finest Zealand (crop) madder are inclosed in a bag of fine, dense calico, 
 large enough to hold three or four times the quantity. A pint of pure water 
 is poured upon it, in a Wedgwood or stone-ware mortar, and it is pressed and 
 beaten with the pestle — taking care not to rupture the bag — as long as any 
 colour can be expressed out of it. The liquid is then poured off. This treat- 
 ment is repeated five times, with successive portions of water. The collected 
 liquid is then heated to near boiling, in a silver or stone-ware vessel, and 
 poured into a pint of boiling pure water, in which 1 oz. of alum — absolutely 
 free from iron — has been previously dissolved. Into the mixed liquid 
 ij fluid ozs. of a saturated solution of carbonate of potash is now gradually 
 poured, with constant stirring. The product is washed, first by decantation, 
 and then on the filter, and carefully dried. The yield is £ oz. 
 
 Madder-lakes are at present generally made from charbon sulphurique, from 
 garancin, or commercial alizarin. If garancin is used it is boiled in a block-tin 
 pan with 20 times its weight of pure water, and alum, perfectly free from iron, 
 equal to one-fourth or one-half the weight of the preparation of madder 
 employed. The boiling is maintained for some hours. It is then allowed to 
 settle; the solution, which is not quite clear, is drawn off; and the same 
 operation is repeated three or four times with the former quantities of water 
 and alum. The red extracts thus obtained are filtered, as quickly as possible, 
 through flannel, but are preferably not mixed together. From the first, more 
 saturated solutions, brown flakes are deposited in the course of a few days, 
 
HMBBtt— MBBBBBBBBW— — MflflHHfl 
 
 .. 
 
 
 BB 
 
 3 66 
 
 DYEING AND CALICO PRINTING. 
 
 from which the very finest lakes can be prepared. For this purpose the clear 
 liquid is drawn off with a syphon as far as possible, and the flakes are 
 separated from the rest of the liquid by filtration. The clear liquid is used 
 for the preparation of ordinary lakes. The precipitation of the colour is the 
 next step : this can be effected by the addition of carbonate of potash or of 
 soda, or caustic, ammonia, with or without an admixture of tin-crystals. 
 Chalk may also be used instead of the alkali, in which case gypsum is thrown 
 down along with the alumina and colouring matter. If the whole of the 
 alumina is thrown down the colour of the product is, of course, lighter. All 
 lakes in which chalk is not employed have a smooth fracture. Each precipitant 
 modifies somewhat the tone of the red produced. If a little salt of tin is 
 added during the precipitation, or at its end, the fire of the lake is heightened, 
 as the tin appears to prevent the precipitation of a trace of a yellow colouring 
 matter. To retain this impurity in solution it is also well not to precipitate 
 the whole of the alum. When the bulk of the alum has been thrown down, 
 the lake is separated by filtration from the yellowish supernatant liquid. 
 
 To prepare the deepest madder-lakes, known as " crystallised " and 
 " Munich " lakes, the above-mentioned brown flakes are dissolved in the 
 smallest possible amount of caustic ammonia. The solution is filtered through 
 linen covered with good filter-paper, and with this solution lakes of uncommon 
 depth and brilliance can be prepared. The precipitation may be effected with 
 alum, with salt of tin, or with a mixture of both, either warm or cold. 
 
 "Splendid lakes can be prepared from artificial alizarin, and, doubtless, from 
 Perkin's artificial purpurin. (See also p. 268.) 
 
 2. Lakes of the Red Woods. — The chief points to be attended to in the 
 preparation of these lakes are — That the decoction of the wood employed be 
 not too recent ; it must have been allowed to stand for some time, and to 
 deposit certain impurities, before it can be used with advantage. The addition 
 of a certain quantity of dilute solution of glue, or of carefully skimmed milk, 
 is here advantageous. Alum, or tin-crystals, or a mixture of both, — of course 
 in known quantities, — is then added, and the precipitation determined by 
 means of alkaline carbonates, &c, as directed for madder. The common 
 lakes are let down with starch, sulphate of lime, China clay, sulphate of 
 baryta, &c. These articles are added during the precipitation, and greatly 
 increase the yield of the lake at the sacrifice of its brilliance. 
 
 Lakes of a great variety of shades may further be obtained by the substitu- 
 tion of bismuth or antimony for tin and alumina. 
 
 3. Cochineal Lakes. — See pp. 359 and 360. 
 
 B. Blue Lakes. 
 
 A blue lake may be obtained by mixing a decoction of logwood, duly aged 
 and clarified, with a little bichromate of potash, afterwards with a solution of 
 sulphate of copper, and lastly with ammonia. 
 
 C. Green Lake. 
 
 Extract 1 lb. of raw coffee-berries with a gallon of pure water, and add a 
 solution of 2$ to 3 lbs. of sulphate of copper. 
 
LICHENS. 
 
 367 
 
 D. Yellow and Orange Lakes. 
 
 1. Annatto Lakes. — A yellow lake may be obtained by mixing the aqueous 
 decoction of annatto with carbonate of soda, bringing the liquid to a boil, and 
 then precipitating it with a solution of alum in excess. 
 
 An orange lake may be prepared from the same dye-ware by boiling it in 
 carbonate of soda, and then precipitating with alum or salt of tin. A redder 
 orange is produced by boiling the ware first in water, and rejecting the solution ; 
 boiling again in solution of carbonate of soda, and precipitating this latter 
 extract with alum or salt of tin. 
 
 2. Fustic Lake. — Extract of fustic, which has been allowed to stand for a 
 few days, is mixed with basic acetate of lead, stirring constantly. 
 
 Yellow lakes can be obtained from other dye-wares by processes similar to 
 the above. 
 
 Aniline Lakes. 
 
 Dissolve in J kilo, of alcohol, at 95 per cent, 10 grms. copal and 1 grm. 
 magenta. Filter, and add dry starch to form a uniform mass, dry, and powder. 
 Other aniline colours may replace the magenta, giving a variety of colours. 
 
 Aurine yields a variety of beautiful precipitates if mixed with metallic and 
 earthy solutions and thrown down by the cautious addition of an alkali. 
 These, however, are not true lakes, but merely hydrated oxides, or sub-salts 
 with which the aurine is mechanically incorporated. On washing with dis- 
 tilled water they lose their colour. 
 
 COLOURING MATTERS DERIVED FROM LICHENS. 
 
 Several kinds of lichens acquire a fine violet colour under the joint influence 
 of ammonia and atmospheric oxygen. This fact, which depends on the 
 presence of one or more peculiar principles, has been empirically known and 
 applied industrially a long time before its theoretical explanation was dis- 
 covered. 
 
 About the year 1300 a Florentine nobleman, named Federigo, discovered 
 accidentally, while on a journey in the Levant, the colour-yielding properties 
 of lichens; and Italy, especially Florence, supplied for more than a century 
 the orchil manufactured with lichens from the Mediterranean. Afterwards 
 the lichens were obtained from the Canary and Cape Verd Islands, and in our 
 days they are imported from Madagascar, Zanzibar, Lima, Guayaquil, Angola, 
 Madeira, Corsica, the Greek Islands, and Sardinia. The weeds belong to the 
 genus known as Roccella, viz., tinctoria and fuciformis, and are distinguished 
 as sea or marine orchil, because the plant thrives on rocks in the sea and along 
 the sea-beach. These plants have a very short, circular base of implantation, 
 from which issue several cylindrically-formed stems, ramifying like the 
 branches of a tree, and terminating in fine points. Their specific characters 
 vary, and so do their colours when dried, ranging from greyish-white to a 
 brown. The richness in tinctorial matter, or rather in the principles capable 
 of becoming pigments, varies even for one and the same kind, but certain tests 
 enable the manufacturer to judge of the quality and purchase accordingly. 
 The land lichens are met with on the naked rocks of the Pyrenees, Cevennes, 
 Alps, and even the Scandinavian mountains, and belong to the genus Vario- 
 

 WMWiiiWiwyuMyW^^B 
 
 ■■■■■■■■■■ 
 
 REH 
 
 368 
 
 DYEING AND CALICO PRINTING. 
 
 laria :—dealbata (Pyrenees), orcina (Auvergne), lecanora tartarea (Sweden): 
 their exterior form is that of an irregular crust, exhibiting hardly any organised 
 texture visible to the naked eye, which distinguishes them very readily from 
 marine lichens. The entire plant was operated upon in the manufacture of 
 orchil from land lichens. The process, as carried on about a. d. 1812, was 
 described by M. Cocq. 
 
 In order to judge of the goodness of the material, a small quantity is put 
 into a glass, and ammonia is poured over it. The good kinds become brown, 
 but the useless, or at least inferior, qualities assume a yellow or green tint. 
 The collected lichen is dried by being spread out in well-aired lofts. 
 
 For the preparation of the colour 100 kilos, of lichen are placed in a wooden 
 trough, wider at the top than at the bottom, and the dimensions of which are 
 as follows :— Length 2 metres by a width of 1 metre, and a depth varying at 
 the top from 0-06 to 0*07 metre and at the bottom 0-04 metre. This trough 
 can be tightly closed by a wooden cover. To the lichen are added 240 litres 
 of human urine, and this mixture is stirred up every three hours during two 
 days and nights. There are added, on the third day, 5 kilos, of slaked and 
 sifted lime, 125 grms. of powdered whi;e arsenic, the same quantity of rock 
 alum ; whereupon the mixture is very frequently stirred. Fermentation sets 
 in ; forty-eight hours after another kilo, of lime is added, and the stirring is 
 less frequently performed. The action is at end after the lapse of a month, 
 when the produft, which becomes better by keeping, is put into casks. The 
 a&ivity of the putrefied urine is due to the presence of carbonate of am- 
 monia, formed by a well-known reaction from the urea. The lime is added in 
 order to set the ammonia free and bind the carbonic acid : the orchil thus 
 obtained is capable of yielding divers colours, viz., by simple treatment with 
 boiling water amaranth is produced, and the intensity of this colour is entirely 
 modified by the lapse of time the woven fabrics are left in the bath, so that at 
 last a brown may be obtained. One of the first improvements in this branch 
 of industry is the substitution of ammonia for the mixture of urine, lime, and 
 arsenic, by which means time is economised and the whole process better 
 regulated. The use of lime was, moreover, found to be rather injurious to the 
 process. 
 
 The principal forms in which these colours are now found in commerce are 
 orchil paste, orchil liquor, cudbear, and " French purple." The paste and 
 liquor are distinguished as " red " and " blue," according as they incline to 
 either of these colours. Cudbear, known on the Continent as persio, is a dry 
 powder, and, from the mode of its preparation, is of 0. reddish cast. The 
 manufacture of these dyes will be described below. 
 
 Since the colouring matter of orchil is soluble in water, that liquid has been 
 employed to extract it from the orchil weeds, — an operation similar to the pre- 
 paration of dye-extracts from the woods, with this difference, that the latter 
 contain the colours ready formed, while in the former it has to be developed. 
 In this way single and double extracts of orchil, and orchil lakes, may be 
 obtained. 
 
 The colourable material of the lichens is not uniformly distributed through 
 the plant, but is chiefly deposited as a greyish powder on the surface, easily 
 detached by mechanical means. M. Frezon has turned this observation to 
 account, by submitting the lichens to the joint action of fridion and water 
 
COLOURING MATTERS OF LICHENS. 
 
 369 
 
 upon a sieve ; a whitish starch-like powder is thus obtained, which, on being 
 treated with ammonia, yields a colour far purer and more beautiful than that 
 obtained by the maceration of the whole weed. 
 
 Before we can further enter into the details of the orchil manufacture, we 
 have to turn our attention to the remarkable discoveries made by chemists in 
 this field, since upon these the improved methods of applying the lichens as 
 dye-materials are based. 
 
 Chemical History of the Colouring Matters of Lichens. 
 
 M. Robiquet succeeded, in 1849, in extracting from the Variolaria dcalbata a 
 colourless, crystalline, saccharine, yet astringent, substance, which he termed 
 orcine. He found, also, that orcine, under the influence of air and ammonia, 
 fixes nitrogen, and becomes converted into a violet-coloured matter. The 
 composition of orcine and of the orceine thence derived were investigated by 
 Dumas, who also found the clue to the precise reaction which accompanies 
 the formation of orceine from orcine. Kane proved that orceine is not the 
 only colouring substance formed by the transformation of orcine. The re- 
 searches on this subject carried out by Heeren, Schunck, Stenhouse, Rochleder, 
 Hesse, De Luynes, Menschukine, Grimaux, and others, have led to the dis- 
 covery and examination of several acids pre-existing in the lichens, which, 
 under varying conditions, split up into orcine and other substances of no in- 
 dustrial moment. From these researches we learn that the existence of 
 ready-formed orcine in the lichens is the exception, since it is only formed 
 when the lichens are treated, and as soon as developed it is further 
 modified. 
 
 Although the chemical history of these acids is not fully elucidated, 
 they have been sufficiently studied to admit of their rational formulae being 
 established and their relations indicated. The acids are — 
 
 1. Erythric acid, or erythrine, C 20 H 22 20 , yielding, as immediate deriva- 
 
 tives, — (a), picroerythrine, C I2 Hi60 7 ; (b), orsellic acid, C8Hs0 4 : picro- 
 erythrine splits up into — (a), erythrite or erythromannite, C 4 H I0 4 ; 
 (b), orsellic acid, which in its turn is split up into carbonic acid, C0 2 , 
 and orcine, C 7 Hs0 2 . 
 
 2. Lecanoric acid.lecanorine, a or /3 orsellic acid, di-orsellic acid, Ci6Hi 4 7 ; 
 
 it is decomposed into orsellic acid, C8Hs0 4 , without production of 
 erythrite or picroerythrine. 
 
 3. /3-Erythrine or /3-erythric acid, C 2 iH 24 O io , a higher homologue of 
 
 erythrine: its products of decomposition are — (a), orsellic acid; 
 (b), /3-picroerythrine, C^H^C^, which differs from its homologue, picro- 
 erythrine, C I3 Hi80 7 , by having H 2 less : it (viz., the /3-picroerythrine) 
 is split up into erythrite and a mixture of carbonic acid, and /3-orcine, 
 C8H I0 2 , which, by combining together, form /3-orsellic acid, — that is 
 to say, a higher homologue of the orsellic acid : /3-orcine is a homologue 
 of orcine. 
 
 4. Evernic acid, C I7 Hi60 7 . the superior homologue of lecanoric or diorsellic 
 
 acid ; it is decomposed into orsellic and evernic, or /3-orsellic acid, the 
 homologue of the first, C 9 H I0 4 . 
 
 5. a and /3 Usnic acids, isomeric with and homologues of evernic acid, 
 
 Ci8H!80 7 ; it is also called di-/3-orsellic acid. Since it yields, when 
 

 EHHHI 
 
 37° 
 
 DYEING AND CALICO PRINTING. 
 
 split up, /3-orcine, we may admit that it might produce /3-orselIic or 
 evernic acid. 
 
 6. Roccellic acid, C I7 H 32 4 . 
 
 7. Roccelline, dsH^O;. 
 
 8. Parelline, or parellic acid, C 9 H60 4 : the two last-named bodies are not 
 
 very well known. 
 
 Erythric acid, or Erythrine, doH^O™, was discovered by M. Heeren, and 
 fully investigated by Drs. Schunck, Stenhouse, Hesse, and De Luynes. It 
 occurs in most of the orchil lichens, and especially in the species known as 
 Roccclla tinctoria, fucifomtis, and Montagnci. This acid is insoluble in cold 
 water, soluble in 240 parts of boiling water, whence, on cooling, it is deposited 
 in the crystalline state. It is more readily soluble in alcohol and ether, 
 boiling alcohol being its best solvent. On cooling, the solution deposits 
 groups of crystals. The alcoholic solution is neutral to test-paper, colourless, 
 inodorous, and tasteless. Erythrine is dissolved by strong sulphuric acid in 
 the cold, and by hot hydrochloric acid ; the former solution is precipitated by 
 cold water. Caustic and carbonated alkalies, and the hydrates of baryta and 
 lime, dissolve erythrine readily, whilst acids precipitate the substance unal- 
 tered, in the shape of a white, bulky, gelatinous mass ; but if the alkaline 
 solutions have been boiled, or kept for a long time, this precipitation does not 
 take place, since erythrine is then altered in a peculiar manner, which we 
 shall presently describe. The ammoniacal solution reddens on exposure to 
 air; with perchloride of iron a purplish colouration is produced. The 
 magnesia-solution of erythrine (erythrite of magnesia) is precipitated by neu- 
 tral acetate of lead, but the alcoholic solution of erythrine is not precipitated 
 by that reagent ; it is, however, thrown down by basic acetate of lead. When 
 erythrine is for a length of time boiled with water it fixes the elements 
 thereof, giving rise to the formation of picroerythrine, carbonic acid, and 
 orcine. This reaction is performed in two periods, during the first of which 
 picroerythrine and orsellic acid are generated, while during the second the 
 orsellic acid is split up into carbonic acid and orcine. If, instead of water, 
 alcohol or wood spirit (pure methylic alcohol) is taken, orsellate of ethyl and 
 orsellate of methyl are produced. Alkalies, especially if aided by heat and 
 lime, greatly favour the transformations of erythrine. 
 
 Dr. Schunck prepares erythrine by exhausting the lichens with boiling 
 water ; the crystalline powder deposited on cooling is purified by the re- 
 crystallisation from alcohol. By this method a portion of the product is 
 modified, and converted into orcine and picroerythrine, whence it is preferable 
 to treat the lichens with milk of lime in the cold. The calcareous solution 
 thus obtained is treated with carbonic acid, whereby carbonate of lime and 
 erythrine are thrown down. This mixed precipitate is next treated with tepid 
 alcohol, and the solution first purified by means of animal charcoal, and, 
 when decolourised and still hot, so much water is added to the alcoholic 
 solution as to produce a permanent turbidity : on cooling, the erythrine is 
 thrown down in a crystalline form.* The calcareous solution may also be 
 precipitated by hydrochloric acid. When the lichens are exhausted with cold 
 weak ammonia a yellow liquor is obtained, containing erythrine and roccellic 
 acid, the latter being a kind of fatty matter, insoluble in water, but soluble in 
 
 * Hesse, " Annalen der Chemie und Pharmacic,'' vol. cvii., p. 297. 
 
COLOURING MATTERS OF LICHENS. 
 
 37 1 
 
 alcohol, ether, and ammonia. These two substances are separated either by 
 precipitation with hydrochloric acid, and subsequent solution of the erythrine 
 in hot water, or by adding chloride of calcium to the ammoniacal liquor, 
 whereby the roccellic acid is separated as insoluble roccellate of lime. Since, 
 however, ammonia also dissolves a brown matter present in the lichens, the 
 purification of the erythrine is not so easy as when milk of lime is used. 
 
 Bromine converts erythrine, in presence of ether, into a crystalline bromated 
 product, insoluble in water, but soluble in alcohol. 
 
 Picroerythrine, C^H^O;, is a solid, white, very bitter body, sparingly 
 soluble in cold water, readily soluble in boiling water; soluble, also, in alcohol 
 and ether. It may be obtained from its concentrated aqueous solutions in 
 crystals; it fuses at 158 ; its reaction with test-paper is slightly acid, With 
 bromine, in presence of ether, it yields a bromated compound. If heated in a 
 sealed tube, orcine is formed. It is soluble in alkalies in the cold ; its ammo- 
 niacal solution reddens easily on exposure to air. Neutral acetate of lead 
 does not yield a precipitate with picroerythrine, but with the basic acetate a 
 precipitate is produced containing 68-94 per cent of oxide of lead ; perchloride 
 of iron gives a purple colouration ; ammoniacal nitrate of silver is reduced to 
 the metallic state. Prolonged boiling with water does not affect picroerythrine, 
 but if, at the same time, baryta or lime is present in excess, water is fixed, 
 orcine, and erythrite, and an alkaline earthy carbonate are formed. This re- 
 action is greatly accelerated at 150 , in sealed tubes. Picroerythrine is 
 obtained by boiling erythrine with water, when it dissolves gradually, and the 
 concentrated liquid yields a brown glue-like mass, which gradually becomes 
 crystalline : on treating this mass with cold water impure orcine dissolves, 
 while picroerythrine remains as a residue. Instead of water alcohol can be 
 taken, and, according to Dr. Stenhouse, erythrine should be treated with lime 
 previous to boiling, in which case the conversion is far more rapid. 
 
 Erythrite Synonyms: — Erythroglucine, erythromannite, pseudo-orcine, 
 C 4 H80 4 . This substance is an important member of the group, inasmuch as 
 the researches of Dr. Hesse and De Luynes have proved that erythrite acts as 
 a tetratomic alcohol, of which erythrine and picroerythrine are the orsellic 
 ethers ; orsellic acid is itself triatomic, and its rational formula is, according 
 
 to Dr. Grimaux, Cs ^ 5 ° r0 3 . 
 
 Without entering here into hypothetical details, we prefer to mention the 
 process of preparation of erythrite and orcine as suggested and carried out by 
 M. de Luynes. Lima lichens are exhausted with milk of lime, the filtered 
 liquid is precipitated with hydrochloric acid ; the erythrine thus obtained is 
 washed, and next heated for two hours in a closed iron vessel, at 150 , along 
 with a certain quantity of milk of lime, too small to effect the entire decom- 
 position of the substance : the carbonate of lime having been separated by 
 filtration, the liquid is evaporated slightly, when, on cooling, orcine separates 
 in the crystalline state ; the evaporation of the mother-liquor yields a crystal- 
 line magma, consisting of erythrite and orcine, which latter is removed by 
 means of ether. The erythrite is purified by solution in boiling alcohol, from 
 which it crystallises on cooling. The calcareous extract may also be boiled, 
 in order to concentrate it ; the lime may be removed by carbonic acid ; the 
 liquid, after removal of this deposit, is evaporated to dryness, and treated with 
 
 ether to remove the orcine. 
 
 2 u 2 
 
■■■MM MB RHHjHMI Hi 
 
 CEEEEE SB jB BEEffB BBBB 
 
 372 
 
 DYEING AND CALICO PRINTING. 
 
 Erythrite yields large crystals belonging to the tetragonal system, somewhat 
 sweetish to taste, neutral to test-paper, very soluble in water, less so in 
 alcohol, almost insoluble in ether; it does not assume any colour, either by the 
 combined action of air and ammonia, or when in contact with hypochlorite 
 of lime. It is neither precipitated by basic nor neutral acetate of lead. It 
 fuses readily, and does not possess the colourable properties of the lichens. 
 It is decomposed by caustic potassa, yielding hydrogen and acetic acid, and 
 when heated to 240 , with that base, hydrogen and oxalic acid are formed. 
 When treated with from 20 to 30 parts of concentrated sulphuric acid, at 6o°, 
 erythrogluci-sulphuric acid is formed : the aqueous solution of this substance 
 is readily and rapidly oxidised when in contact with air or with spongy pla- 
 tinum. When dry erythrite is fused, and heated along with twelve times its 
 weight of hydriodic acid (sp. gr. i'yg), it yields, on distillation, hydriodate of 
 butylen, C 4 H 8 IH. 
 
 Orsellic, or a-Orsellinic, Acid, CsHsO^. — Since orcine is diatomic, and 
 differs from orsellic acid by having C0 2 less, the orsellic acid is, according to 
 Grimaux, triatomic. This acid is best prepared by boiling the lecanorates of 
 lime or baryta for a short time with water ; the ebullition should be carefully 
 conducted, since otherwise carbonate of lime and orcine are formed : the or- 
 sellic acid is precipitated by means of hydrochloric acid ; the ensuing gelatinous 
 precipitate is treated with boiling alcohol or with warm water, and, on cooling, 
 prismatic crystals are deposited. This acid is more soluble in water than 
 diorsellic and lecanoric acids ; its lime and baryta salts are also more soluble, 
 and it is by far more soluble in ether ; its taste is sour and bitterish ; it reddens 
 litmus-paper ; fuses at 176°, but is then also decomposed into orcine and carbonic 
 acid. This reaction is also produced by long-continued boiling. Bleaching- 
 powder gives it a fugitive violet-red colour. In contact with air, caustic 
 ammonia colours it red. The alkaline and alkaline-earthy orsellates are 
 soluble in water, but if any excess of base be present are readily decomposed 
 into orcine and the carbonate of the base. Orsellic acid, combined also with 
 
 methyl, ethyl, and bromine, converts it into tribromorcine. 
 
 C 8 H 5 0| 
 Lecanoric, Diorsellic, o-Orsellic Acid, or Lecanorine, C8H 5 0[0 5 . 
 
 H 4 ) 
 — Schunck found this acid in lichens belonging to the species Lccanora and 
 Vaviolaria, Rochleder and Held in the Evcrnia prunastri, and Stenhouse in 
 the Roccclla tinctoria. It may be prepared by the following process : — The 
 lichens, previously pulverised, are exhausted with ether, the solution is evapo- 
 rated to dryness, and the residue first treated again with ether, next with 
 water, and lastly dissolved in alcohol. The lichens may also be treated with 
 milk of lime or with ammonia, the liquids filtered from the insoluble residue, 
 and the filtrate treated with hydrochloric acid ; the pasty precipitate is sepa- 
 rated by filtration, well washed, dried, and next taken up with alcohol, from 
 which the acid crystallises. This acid then forms white acicular crystals, 
 sparingly soluble in cold water and cold alcohol ; soluble in ether, boiling 
 alcohol, and acetic acid: 1 part of the acid requires for solution 2500 parts of 
 boiling water, 150 parts of alcohol at 15 , 5-15 parts of boiling alcohol, and 
 80 parts of ether. Bleaching-powder colours it temporarily red. The alco- 
 holic solutions of the acid are tinged purplish by the addition of chloride of 
 iron. When the acid is dissolved in ammonia, and left in contact with air, it 
 
COLOURING MATTERS OF LICHENS. 
 
 373 
 
 assumes gradually a violet-red. If boiled along with water and an excess of 
 lime and baryta, first an orsellate is formed, which is, in its turn, when the 
 process is continued, decomposed into carbonic acid and orcine. The sub- 
 stance known as a-orcine, or simply, also, orcine, first discovered by Robiquet, 
 is the colourable material of the lichens, or rather it is — among the ultimate 
 produces of the splitting up of the acids just mentioned — the only substance 
 capable of conversion into a colouring matter. It is not proved, and does not 
 appear probable, that the colouring matter which is the result of the simulta- 
 neous action of air and ammonia upon orcine is identical with the colouring 
 matters which ensue by the ammoniacal oxidation of the colourable acids 
 (viz., erythrine, lecanoric, orcellic, and picroerythrine). Indeed during the 
 manufacture of orchil by the ordinary methods there are formed several 
 colours, all exhibiting different tones. 
 
 Pure orcine forms colourless prismatic crystals, belonging to the monoclinic 
 system.* It is very readily soluble in water and alcohol, and soluble in ether ; 
 from its aqueous solutions it crystallises with one equivalent of water, but the 
 ethereal solution yields anhydrous crystals. Orcine has a sweetish, but at 
 the same time a disagreeable, taste. Its hydrate fuses at ioo°, losing its 
 water of crystallisation; but in the anhydrous state it may be distilled at 290°, 
 and sublimes without decomposition when not submitted to this experiment 
 in large quantity at once. The formula of orcine is C 7 H80 2 + H 2 0, the latter 
 eliminable at 100°, or over sulphuric acid in vacuo, being water of crystallisa- 
 tion. Though orcine is neutral to test-paper, it behaves in some instances as 
 an acid, so that in a state of fusion it decomposes alkaline carbonates, and 
 precipitates silica from alkaline silicates; orcine precipitates the quinine salts, 
 entering into a peculiar combination with that base. Solutions of orcine are 
 not precipitated by bichloride of mercury, neutral acetate of lead, sulphate of 
 copper, tannin, and gelatin, but yield with basic acetate of lead a white, and 
 with chloride of iron a deep red, precipitate. Orcine reduces salts of gold and 
 silver to the metallic state, if ammonia is simultaneously present. Orcine 
 combines with chlorine and bromine ; if thrown into fuming nitric acid which 
 is kept cool, it dissolves therein without giving off nitrous vapours. This 
 solution is precipitated by water, yielding a red substance soluble in alkalies. 
 When crystallised orcine is placed under a bell-jar, close to a vessel containing 
 nitric acid (sp. gr. 1384), it becomes first brown, and then red. This change 
 proceeds for some days. The substance thus produced differs essentially from 
 orcine ; it dyes silk and wool red, without requiring any mordant. Ammonia 
 changes this colour temporarily to a violet ; fixed alkalies do so permanently, 
 but acids restore the original colour. f On treatment with a large excess of 
 concentrated sulphuric acid, and exposure to a temperature of from 6o° to 80°, 
 oicine becomes black. If water is added to the acid after cooling, and the 
 liquid saturated while cold with carbonate of lead, then filtered, and 
 the clear filtrate concentrated by evaporation, a crystalline mass is obtained 
 which, if treated with ether, yields orcine. On dissolving the residue in 
 boiling water, re-treatment with carbonate of lead, filtering again, and setting 
 aside the liquid, it yields brownish crystals of basic orcino-bisulphate of lead, 
 
 * Laurent and Gerharc.lt, " Annales de Chimie et de Physique" [3], vol. xxiv., p. 317, 
 Miller, " Ann. der Chem. und Pharm.," vol. Ixviii., p. 99. 
 } Dc Luynes, " Comptcs Rendus de l'Academie des Sciences," vol. lvi., p. 715. 
 

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 374 
 
 DYEING AND CALICO PRINTING. 
 
 with a nacreous reflection. Contadl of air and sunlight tend to redden orcine 
 gradually ; bleaching-powder colours it first a deep violet, but which turns 
 gradually to a brown, and becomes finally yellow. Under the influence of 
 fixed alkalies orcine absorbs oxygen very rapidly, and assumes a red or 
 brown colour. Vapours of ammonia convert orcine into a deep brown 
 substance, orceine ; bichromate of potassa, either with or without addition of 
 sulphuric acid, converts orcine into a brown substance, while the prolonged 
 aclion of nitric acid, aided by heat, produces oxalic acid. 
 
 Orcine may be prepared by various processes. Robiquet obtained it by 
 exhausting Variolaria with boiling alcohol : this liquid deposits, on cooling, 
 crystals, which are first removed, after which the fluid is evaporated to 
 dryness. The dry residue, treated with boiling water, yields, on concentra- 
 tion, crystals of orcine. Dr. Schunck boils lecanorate of baryta with water 
 for a long time ; carbonate of baryta is precipitated, while orcine remains in 
 solution, and is purified by repeated crystallisation. Dr. Stenhouse extra&s 
 the lichens in milk of lime, boils and concentrates the liquid, precipitates the 
 lime by carbonic acid, evaporates the liquid to dryness, and takes up the 
 residue with concentrated boiling alcohol. The crystals of orcine which 
 separate from this liquid, on cooling, are re-dissolved in pure anhydrous ether. 
 The best process for preparing orcine is that above described, as devised by 
 M. de Luynes. Dr. Stenhouse has extracted from the Roccclla tine tor ia, of 
 the Cape of Good Hope, a substance termed roccellinine, by the following 
 process : — The lichen is treated with a cold milk of lime, the liquor is filtered, 
 and next precipitated by hydrochloric acid ; the ensuing pasty white precipi- 
 tate is first washed with water, and next boiled with alcohol : this procedure 
 causes the formation of orsellate of ethyl, which is soluble in boiling water, 
 while the unaltered roccellinine is not thereby dissolved, and maybe separated. 
 
 Roccellinine is soluble in ammonia and alkalies, but these solutions do not 
 become coloured on exposure to air; it is almost insoluble in alcohol and 
 ether when cold, but the boiling alcoholic solution deposits, on cooling, silky 
 needle-shaped crystals, which, according to Dr. Stenhouse, consist of 
 C I sH I 60 7 . 
 
 Parelline,or Parellic Acid, according to Dr. Schunck, accompanies lecanoric 
 acid. In order to obtain the former acid, lichens are exhausted with boiling 
 alcohol, and the liquid thus obtained boiled for some time, and next evaporated 
 to dryness. The residue is taken up in boiling water, to dissolve the orsellate 
 of ethyl ; the residue is treated with boiling alcohol, from which the parellic 
 acid separates; on cooling, in the shape of fine crystnllin? needles, insoluble 
 in water, but soluble to some extent in cold alcohol and ether. This sub- 
 Stance, C 9 Ho0 4 , it appears, does not yield, when treated with ammonia and 
 in contaft with air, any red or violet matters. 
 
 Colouring Matters of Orchil. 
 Although there is no doubt that in the dye known as orchil several different 
 pigments exist, only one of these, viz., orceine, — formed according to the 
 researches of MM. Robiquet and Dumas, at the expense of orcine,— has been 
 closely investigated. This orceine requires for its formation two conditions: 
 — the presence of atmospheric oxygen and that of ammonia, while a tem- 
 perature of from 30 to 50 favours its generation. When orcine in a crystal- 
 
ORCHIL. 
 
 375 
 
 lised state is exposed to the action of ammoniacal vapours this conversion 
 takes place, and equally so when an aqueous solution of orcine containing 
 from 10 to 20 per cent is exposed to the action of these vapours : time is a 
 very essential item in this process. According to M. Dumas, the formula of 
 orceine is C 7 H 7 NC>3, and the formation of this substance from orcine may 
 therefore be elucidated by — 
 
 C 7 H 6 2 + NH3 + 3 = C 7 H 7 N03 + H 2 0. 
 
 Orcine. Orceine. 
 
 Dry orceine is a brown powder, somewhat soluble in water, to which it 
 imparts a red colour. The neutral alkaline salts precipitate this solution. 
 Orceine is insoluble in ether, but very readily soluble in alcohol, giving a 
 scarlet solution ; alkalies and ammonia also dissolve it, yielding magnificent 
 purplish-violet solutions. Orchil as met with in commerce exhibits, under 
 similar conditions, the same phenomenon ; it is essentially orceine in combi- 
 nation with ammonia (orcineate of ammonia), which yields, when dissolved in 
 water with various metallic salts, diversely coloured precipitates or lakes, but 
 after drying the colour of these bodies is very faint. Orcineate of ammonia 
 is decolourised by reducing agents, as, for instance, by boiling along with 
 water and metallic zinc, or addition of sulphydrate of sulphide of ammonium, 
 but the colour reappears on exposure to air. When an ammoniacal solution 
 of orceine is acidified with hydrochloric acid, and zinc added, the fluid is 
 decolourised. The addition of ammonia to this liquid causes the precipitation 
 of a flocculent white matter, leucorceine, which, on exposure to air, becomes 
 violet and purplish. Chlorine converts orceine into a yellowish-brown matter, 
 chlororceine. Orceine is, by itself, a red substance, which, under the influence 
 of alkalies, becomes violet, but acids restore the primitive red colour. 
 
 Dr. Kane has found, in the orchil of commerce, two other red matters, 
 orceine and azoerythrine. and, moreover, a semi-fluid purplish substance, 
 erythroleic acid. The azoerythrine, CnH ig NOii, is insoluble in water, alcohol, 
 and ether, but soluble in alkalies, to which it imparts a wine-red colour ; ery- 
 throleic acid, C18H11O4, is soluble in alcohol, ether, and alkaline solutions, but 
 insoluble in water. These products have not been, however, sufficiently 
 investigated. 
 
 New Methods of Preparing Orchil. 
 The researches above mentioned, more especially those of Drs. Schunck, 
 Stenhouse, and Rochleder, have led to great improvements in the manufacture 
 of orchil, especially in this respect — that the colourability of the lichens is not 
 a property of these plants as a whole, but is due to some principles therein 
 contained, which are capable of being rendered soluble by suitable reagents, 
 or may be set free by mechanical means. These colourable materials form 
 only a very small portion of the total weight of the lichens. The chemical 
 operations are, moreover, rendered easier and more manageable if the large 
 bulk of ligneous matter is removed. 
 
 We have already observed that Frezon utilises the slight adherence of the 
 erythrine and the lecanoric acid, which are chiefly on the surface of the 
 plants, in order to isolate and detach these substances. This is effected as 
 follows: — The lichens, previously sorted and washed several times with cold 
 water, are ground up to a somewhat liquid paste. This paste is exhausted 
 by washing several times with cold water ; the liquids obtained are filtered 
 
■■■■■ WH 
 
 ^^^q junum 
 
 376 
 
 DYEING AND CALICO PRINTING. 
 
 through a peculiar kind of loosely-woven, felty, woollen tissue, which retains 
 the ligneous matter, but admits of the passage of the partly dissolved, partly 
 suspended colourable acids. By the addition of a small quantity of bichloride 
 of tin, the colourable matters are coagulated, and collected on filters made of 
 stout linen tissue. After having been once more washed with water the mass 
 is dissolved in ammonia, and placed in properly constructed tanks, wherein, 
 by the aid of a proper temperature and frequent stirring, the material is con- 
 verted into orchil, an operation which requires a long time. The progress of 
 this operation is tested by dyeing, with a certain weight of the orchil, a certain 
 size of woollen tissue. By this means, also, the end of the operation — that 
 is to say, the period of highest intensity of colouration — is ascertained. 
 
 M. Gauthier de Claubry has observed, and very properly so, that the pro- 
 longed contact of the lichens with water has the effect of rendering the 
 colourable matter soluble, so that, unless the operations described are carried 
 on very rapidly, a loss may be sustained. 
 
 Dr. Stenhouse suggests that the lichens should be treated, at the spots 
 where they are collected, with milk of lime, 30 per cent of lime of the weight 
 of the lichens ; the liquid filtered, precipitated with hydrochloric acid, and the 
 white pasty precipitate filtered off, which, after having been washed and dried, 
 should be conveyed to the orchil manufacturers, since it contains in small 
 bulk all the really valuable matters of the lichen, while the expense of transport 
 would become less. The great objection to this plan is, that (while it might 
 otherwise be also employed in the manufacture of orchil from the lichens brought 
 to Europe) in contact with lime the erythric and lecanoric acids are very 
 rapidly altered, and the matter spoiled, so that even so short a maceration 
 with lime as three hours is injurious. Ammonia might be used to extract 
 from the lichens the colourable acids, but the paste obtained by precipitation with 
 hydrochloric acid is yellowish-brown, owing to the ammonia simultaneously 
 dissolving a peculiar brown matter present in the lichens. Moreover, the 
 same objection as for lime holds good for the use of ammonia. When the 
 colourable principles of the lichens are extracted by prolonged boiling, with 
 either water alone or water to which an alkaline substance (any alkaline phos- 
 phate, borate, carbonate, or also any caustic alkali) is added, the conversion 
 of the insoluble substances precipitable by acids into soluble matters no longer 
 precipitable is rapidly brought about, and therefore the liquids have to be con- 
 centrated by evaporation. 
 
 The ordinary method of preparing orchil paste is as follows : — The apparatus 
 used is a wrought-iron horizontal cylinder, made very smooth within, about 
 6 feet in length and 3 feet in diameter. The lowest third part of the circum- 
 ference, for the entire length, is fitted with a steam-jacket for the application 
 of heat. A shaft runs through the cylinder axially from end to end, fitted 
 with paddles and worked by steam-power, in order to agitate the mass. 
 Along the top runs a slit from end to end, with a movable lid, for introducing 
 the charge of weed and ammonia. There are also a few small slides for regu- 
 lating the supply of air. In the front of the cylinder, below the axle of the 
 agitator, is a man-hole, for discharging, and above the axle, right and left, are 
 two small slides for the admission of air. A cylinder, of the dimensions 
 given, is charged with 180 lbs. of weed and 540 lbs. ammonia, at 5° of the 
 common ammonia-glass, which corresponds almost exactly with Baume's 
 
ORCHIL. 
 
 377 
 
 hydrometer for liquids lighter than water. The charge can be ready in three 
 days, but the quality is improved if worked for a week. Steam is admitted 
 into the casing by a pipe at the end opposite to the man-hole, and the tem- 
 perature is kept up at such a height that the paste feels slightly uncomfortable 
 to the hand — about 6o° C. or 140 F. The agitator is kept gently revolving 
 all the time. The admission of air is regulated according to the judgment of 
 the manufacturer. The yield, for the quantity given above, is 540 lbs., or 
 three times the weight of the weed employed. An excess of ammonia renders 
 the colour less stable, impairing its affinity for the fibre. It should be men- 
 tioned that the blue shade makes its appearance first, and by proper manage- 
 ment the change can, if desired, be arrested at this point. The red shade 
 appears when the joint action of air and ammonia is allowed to proceed to a 
 greater length. 
 
 To prepare orchil liquor the weeds are boiled out with water, and strained ; 
 the extradl concentrated to 8° to io° Tw., and then heated and agitated with 
 ammonia at 24 of the ammonia-glass. Continual agitation is here not neces- 
 sary. The arrangements for extracting the weed are various. It is generally 
 boiled in three successive waters, the first and second liquors being mixed and 
 concentrated, whilst the third serves for the first extraction of a fresh quantity 
 of the weed. The weeds for paste and liquor should not be ground too fine, 
 being bruised under edge-stones rather than pulverised. Certain additions are 
 frequently employed by manufacturers. Small quantities of red prussiate 
 (ferricyanide of potassium) give the orchil a redder tone, whilst a slight 
 addition of a fixed alkali — generally carbonate of potash — serves to give an 
 extra blue shade. An improved bloom and brilliance is imparted by a little 
 tartar, or white argol. 
 
 The manufacture of cudbear is very simple. Orchil paste, made as above 
 described, is dried at a steam-heat, and afterwards ground to a fine powder in 
 a lac-mill. It is very generally weighted with common salt, and its appearance 
 is often factitiously improved by the addition of a little magenta. 
 
 Orchil paste varies greatly in quality, from variations in the lichens used in 
 the manufacture, from the degree of care and skill used in the process, and 
 from the presence or absence of impurities. It may be too watery, containing 
 not more than 20 per cent of solid matter, in which case an extra quantity is 
 needed to produce the shades required. The amount of moisture is readily 
 found by weighing out a quantity, and drying, at the heat of boiling water, 
 till no further loss is experienced, and then weighing the residue. Orchil may 
 have been overdone with ammonia, in which case its affinity for the fibre will 
 be feeble. If a cask of orchil paste, when first opened, gives off a pungent 
 ammoniacal smell, it may be pronounced faulty, but time and exposure to air 
 will correct this defect. Practical men often judge the quality of an orchil 
 paste by rubbing a little on the back of the hand, and permitting it to dry. If 
 the colour is well made a stain will remain on the skin, which cannot readily 
 be removed by washing in cold water or rubbing with a cloth. If the colour 
 is bad, and especially if it be too ammoniacal, it is easily washed off with 
 cold water. 
 
 Orchil is sometimes fraudulently mixed with extracts of logwood, sapan, &c. 
 To detect these, about 50 grs. of the suspected sample are stirred up in 
 3 ozs. of water ; 50 drops of a solution of protochloride of tin, made by 
 
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 378 
 
 DYEING AND CALICO PRINTING. 
 
 dissolving tin crystals in double their weight of water, is then added, and the 
 whole is brought to a boil. A pure orchil gives only a faint yellowish colour. 
 The presence of logwood is shown by a greyish-blue residue, whilst sapan or 
 peach-wood is indicated by a reddish tinge. The actual beauty and tone of 
 different samples of orchil can only be ascertained by dyeing swatches of 
 some suitable material-such as white camlet, French merino, or flannel — with 
 equal weights of the samples under examination, under circumstances quite 
 similar. 
 
 Orchil liquor is used in dyeing wool and slubbings which could not readily 
 be freed from fragments of the weed if the paste were employed. Liquors 
 range in strength from 8° to 20 c Tw. They are best tested by dyeing compa- 
 rative samples. 
 
 Cudbear, in addition to salt, is sometimes adulterated with ground chalk. 
 These impurities may be detected by burning a weighed quantity to ashes. 
 If genuine, the residue will be inconsiderable. Or swatches of a white 
 woollen or worsted material, equal in weight, are dyed with equal weights of 
 the samples. 
 
 Since the year 1857, MM. Guinon, Marnas, and Bonnet have obtained from 
 lichens a product known as pourpre Franraisc, which yields not only an 
 extremely beautiful and brilliant but fast dye-material. This dye-material is 
 prepared as follows : — The lichens are treated with a cold ammoniacal liquid, 
 whereby the colourable acids are dissolved. After having been in contact with 
 this fluid only for a few minutes, the lichens are placed on a filter, in a bag, 
 which is squeezed very strongly, the filtered liquid is precipitated with hydro- 
 chloric acid, the ensuing precipitate is filtered, washed and left to drain, and 
 next dissolved in ammonia, and left exposed to the action of air in the cold. 
 Up to this part of the proceedings there is no difference from the ordinary 
 method of orchil making, but instead of allowing the process to go on until 
 the peculiar colour of orchil is completely developed, the moment when the 
 liquid mass becomes a cherry-red is watched, and, as soon as that point has 
 been reached, the material — semi-fluid, or thickish fluid — is brought to ebulli- 
 tion, which is kept up for some time. It is then run into flat-bottomed, rather 
 shallow vessels, of from 2 to 3 litres capacity each, so as to form layers of 
 from 5 to 6 centimetres in thickness : these vessels and contents are heated 
 to from 70 to 75 , in a properly constructed stove-room : the operation is 
 finished when the liquid has assumed a beautiful purple tint, and does not, 
 when painted over a sheet of white paper, change its colour after drying. 
 The purple matter thus obtained is accompanied by a red acid, which alters 
 its beauty. In order to eliminate that acid chloride of calcium is added, when 
 a precipitate, or lime lake, is obtained, which, after having been filtered, 
 washed, and dried, appears a bluish-purple mass, and when rubbed with the 
 finger-nails assumes a cupreous hue. By fractional precipitation lakes of 
 different shades are obtained. The mother-liquor retains, beside some of the 
 purple, a red substance, which may be applied to dye pomegranate-colour on 
 silk, and is also a fast colour.* 
 
 Instead of a lime lake an alumina lake may be prepared by employing 
 alum for the precipitation of the ammoniacal solution. By treating the lime 
 lake of the pourprc Franqaise with an equivalent quantity of oxalic acid, and 
 
 * J. Pcisoz, " Repert. de Chiin. Appliq.," vol, i., p. 189. 
 
ORCHIL. 
 
 379 
 
 exhausting afterwards with boiling alcohol, the purple matter is obtained, 
 when the alcoholic liquid is evaporated in the shape of crystals. This sub- 
 stance has not been as yet chemically investigated. The price of this French 
 purple was at first 200 francs (£8) per kilo. ; it has come down to 80 francs 
 (£$ 5 s -)' a "d > s distinguished from ordinary orchil by not being reddened by 
 vegetable acids. 
 
 The researches made by M. Gauthier de Claubry have proved that the pro- 
 duction of French purple is mainly due to that portion of the process (the 
 stoving) and the keeping up thereby of a very uniform temperature. The 
 same chemist also ascertained that when orchil is prepared at 6o° a product is 
 obtained yielding more solid dyes than when manufactured at lower tempera- 
 tures. Although the process of making orchil is known in its general 
 features, every individual manufacturer keeps his own peculiar process and 
 everything relating thereto secret. The quantity of colourable matter of the 
 lichens can vary from 2\ to 12 per cent. In order to ascertain comparatively 
 the tinctorial value of the various samples equal weights thereof (100 grms.) 
 are macerated for a short time — a few minutes — with milk of lime ; the liquid 
 is placed on a stout cloth, filtered, squeezed, and precipitated by means of 
 hydrochloric acid ; the resulting white paste is placed on a small silk sieve, 
 rapidly washed, well drained, and weighed. Dr. Stenhouse applies a standard 
 solution of bleaching-powder, which, on being added drop by drop to the 
 calcareous lichen extract, causes first the production of colouration, and as 
 soon as that has attained its summit decolouration ensues ; by comparing the 
 degrees of solution of hypochlorite required for the production of these 
 phenomena in different solutions of lichens their goodness may be approxi- 
 mately estimated. 
 
 Another process is to exhaust 100 grms. of lichens with water rendered 
 alkaline ; this liquid may be concentrated by evaporation to 100 grms., and 
 the coloisration may be caused by the addition of 30 grms. of ammonia. In 
 other terms the orchil manufacture is executed on the small scale; a dyeing 
 process with unmordanted wool will give some idea of the quantity of 
 colouring matter formed. The manufactured article, orchil, is tested by a 
 dyeing process with unmordanted wool ; for a piece of that material 5 centims. 
 long by 2 centims. wide from 0*5 to i - o grm. of orchil and 300 grms. of water 
 are taken. These materials are put in a suitably sized glass vessel placed in 
 a water-bath, and kept at a boil for half an hour. When it is desired to test 
 the orchil by printing, 100 grms. of gum water, 12 of sulphate of alumina, 
 100 of orchil are mixed and printed by roller or block over a sufficiently large 
 surface of wool, which is afterwards steamed. 
 
 Applications of Orchil in Dyeing and Printing. 
 Orchil is never applied to cotton or calico, for although it might be fixed 
 upon that fibre by means of animal mordants the colours thus obtained are 
 neither sufficiently fast nor brilliant enough to be of any use. This remark 
 does not apply to French purple, which is brilliant as well as fast. In order 
 to print French purple on cotton the lime or alumina lake is dissolved in a 
 mixture of acetic acid and alcohol, next a solution of albumen is added. 
 M. Kopp gives the following prescription, which may, of course, be varied to 
 some extent: — French purple, 25 grms.; acetic acid, 50 grms.; alcohol, 
 
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 3 8o 
 
 DYEING AND CALICO PRINTING. 
 
 80 grms. ; albumen water, 1 litre; if a bluish hue is desired some neutral 
 indigo extract should be added. The materials are printed, dyed, steamed, and 
 next washed in boiling water. 
 
 Cotton as prepared for Turkey -red dyeing (oiled cotton), or also cotton pre- 
 viously albuminised, take up this colouring matter when placed in a bath con- 
 taining the purple (previously decomposed with its weight of oxalic acid, 
 filtered, to eliminate the oxalate of lime, and next dissolved by the aid of 
 some ammonia) ; the temperature should be raised to 6o°. Non-mordanted 
 wool placed in a boiling hot bath of the ordinary orchil of commerce assumes 
 a beautiful and pure red, violet-red, or violet, according to the quality of the 
 product used. French purple decomposed, or rather deprived of its lime and 
 set free by means of oxalic acid and neutralised with ammonia, yields, upon 
 wool, a very beautiful and fast violet-purple. For the so-called bright groseille- 
 red and deep violet-groseille, wool, previously mordanted with tin, is dyed 
 with orchil only, 10 kilos, of wool, 1 kilo, of cream of tartar, 2 litres of tin 
 solution (made up of 400 grms. of common salt, 1-25 kilos, of tin, and 8 litres 
 of nitric acid) ; the wool is kept for an hour in this mixture at boiling heat. 
 For medium groseille-red ammoniacal cochineal and orchil are used together. 
 Orchil is also used along with other dye-wares to obtain the following 
 colours : — 
 
 Amaranth Red. — Mordant for red. Crude cochineal and orchil. 
 
 Amaranth Bright. — For medium and deeper hues the quantity of orchil 
 taken is increased, and as regards the very deep hues sulphate of indigo also 
 is added. 
 
 Amaranth Violet. — As for preceding. 
 
 Feuille Morte.* — The mordanting is done with alum and sulphuric acid 
 (10 kilos, of wool, 2 kilos, of alum, 20 grms. of sulphuric acid, boiled together 
 with water for an hour) ; the dye material consists of a mixture of orchil, 
 neutral extract of indigo, and turmeric. 
 
 Wood Colour (Bois). — Mordanting with cream of tartar and tin solution, 
 dyeing with orchil, neutral extract of indigo, turmeric, and fustic liquor. 
 
 The shades known as pommerolle and carmelite are produced by the same 
 mordants and dye-wares, the only difference being the quantities applied. 
 Very large quantities of orchil are consumed in printing woollen fabrics 
 (steam colours). As examples of the shades and of the mode of preparation 
 the following may serve : — Reddish brown (puce) orchil liquor, 2 litres ; 
 sulphate of alumina, 120 grms. ; Senegal gum, 200 grms. Brown (puce) 
 oichil liquor, 2 kilos. , sulphate of alumina, 120 grms.; Senegal gum, 200 grms.; 
 indigo carmine, 60 grms. After printing and dyeing the goods are steamed 
 and next washed. In order to apply French purple as steam colour upon 
 wool and silk the dye material is dissolved in acetic acid, neutralised with 
 carbonate of magnesia ; alcohol is added, and gum water as thickener; these 
 are applied by cylinder, and the fabric afterwards steamed. 
 
 Orchil dyes silk directly without the use of any mordant, the shades being 
 similar to those produced on wool. The French purple yields on silk a 
 beautiful mauve or dahlia colour when used alone. If mixed with indigo ex- 
 tract it yields a very good violet; with cochineal, peach-blossom, groseille, 
 
 * A peculiar hue which the leaves of many trees and shrubs assume in the autumn just 
 previous to falling. 
 
LITMUS. 
 
 38i 
 
 and lilac. The material known as litmus is also a product from lichens, and 
 is obtained by a modified process of setting in action the colourable principles 
 contained in them. Litmus is rarely if ever used in dyeing, although it 
 colours silk blue and violet, but the colours produced are so fugitive as to be 
 only employed in extreme fancy styles. 
 
 Litmus was chiefly used for washing blues, for colouring wine, vinegar, and 
 cordials, and is still employed by chemists for the preparation of the so-called 
 litmus paper. The ordinary litmus of commerce is made from the Roccella 
 lecanora and variolaria, lichens obtained on the coasts of the Mediterranean, 
 in Sweden, Norway, and the Canary Islands. The raw material is chiefly 
 sent to Holland for conversion into litmus, which is done by adding to the 
 lichens, previously ground to a pulpy mass, a mixture of ammonia and car- 
 bonate of potassa (pearl-ash). The paste is left to ferment until a violet 
 colour appears. When this stage is reached lime is added, and also another 
 quantity of pearl-ash and some stale urine, when the mixture is left to fer- 
 ment for some three weeks longer, until a blue colour is obtained. The pulpy, 
 semi-fluid mass is rendered more solid by the addition of chalk and some 
 plaster-of-paris, the excess of liquor is separated by means of sieves, and after 
 having become sufficiently dry is shaped in jujube or lozenge form, dried 
 either in the open air (in summer) or in heated drying rooms, and delivered 
 to the trade in seven different qualities, No. 1 containing most, and No. 7 least 
 chalk. Litmus so prepared is a dry, light blue substance, the better the 
 quality the less insoluble matter it contains. 
 
 The orchil prepared by the action of ammonia upon lichens does not become, 
 when treated with acids, perfectly red, and that colour is not rendered blue by 
 contact with ammonia and alkalies ; the presence of carbonate of potassa as 
 used in the manufacture of litmus has therefore the effect of modifying the 
 process of oxidation of the colourable matters, so as to result in the formation 
 of a red acid, which, with alkalies, forms a blue salt. The blue colour of the 
 litmus of commerce is therefore due to the colour of a potassa salt of a red 
 acid. The real colour of that acid is made apparent by the action of stronger 
 acids upon litmus, the aqueous or alcoholic solutions of which all contain 
 an excess of alkali, which has to be saturated first before the colour begins 
 to turn to red. 
 
 Since litmus is used as a reagent of some value in chemistry its pre- 
 paration so as to be most sensitive and delicate for that purpose may not 
 be here out of place : to the litmus solution is added a slight excess of 
 acetic acid; it is next carefully neutralised with ammonia, and then boiled for 
 a long time so as to expel the last traces of any free volatile alkali. All 
 chemists are aware that litmus tinctures when kept in stoppered bottles be- 
 come gradually discoloured in consequence of a peculiar reductive fermenta- 
 tion, but exposure to the oxygen of the air is sufficient to restore the original 
 colour in full strength. Something similar takes place with orchil ; both these 
 substances are similarly affected by the action of reducing agents. 
 
 Kane and Gelis have studied the peculiar blue produced from the lichens as 
 present in litmus. The former chemist has found in litmus from three to four 
 distinct colouring matters, which he isolates by the following process: — Litmus 
 is ground to a coarse powder and exhausted with boiling water ; the insoluble, 
 pale blue residue is treated with a slight excess of hydrochloric acid, whereby 
 

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 3S: 
 
 DYEING AND CALICO PRINTING. 
 
 a red flocculent matter is separated, which, on being collected on a filter, is 
 washed, dried, and next exhausted with boiling alcohol. This solution is 
 evaporated to dryness, and the residue being again treated with alcohol yields 
 a beautiful red semi-fluid substance (erythroleine), soluble in ammonia, with 
 a purplish colour. There is besides dissolved in the alcohol another deep red 
 matter, soluble in ether, and exhibiting a crystalline structure, forming a blue 
 compound with potassa, and with ammonia a blue but insoluble substance 
 (erythrolitmine). There remains after the first-mentioned treatment with 
 alcohol a brownish red, amorphous body, insoluble in alcohol and ether, but 
 soluble in water. It forms with ammonia and the alkalies blue solutions. 
 This is the most important constituent of litmus, being the material which in 
 the state of a blue potassa salt is dissolved in water, when the litmus of 
 commerce is treated with that liquid. The body has been named by Dr. 
 Kane, azolitmine, and contains nitrogen, which is not present in erythroleine 
 and erythrolitmine. According to the author just named, the composition of 
 azolitmine is C 7 H 7 N0 4 , its formation from orcine being according to the 
 following formula: C 7 H 6 2 + NH 3 + Og = C 7 H 7 N0 4 + H 2 0. The action of 
 carbonate of potassa produces a more energetic oxidation of the orcine. 
 
 Dr. Gelis first exhausts litmus with boiling water ; the residue is boiled 
 with a weak solution of potassa. Both liquids are then mixed and pre- 
 ciptated with subacetate of lead. The precipitate, after having been well 
 washed and suspended in water, is decomposed by sulphuretted hydrogen ; 
 the ensuing precipitate of sulphide of lead containing the colouring matter 
 is exhausted with an ammoniacal water. This solution being acted upon by 
 hydrochloric acid yields a flocculent precipitate of colouring matter, a small 
 portion of which remains in solution. This flocculent matter being treated 
 with ether yields a red, somewhat crystalline body, soluble in alkaline 
 liquids, with a violet colour. The residue insoluble in ether, being treated 
 with alcohol, yields a blood-red solution, which, when evaporated to dryness, 
 leaves a purplish red body with a golden reflection, the main coloured con- 
 stituent of litmus. There remains, moreover, a body insoluble in water, 
 alcohol, and ether, but soluble in alkalies. From this account it is sufficiently 
 clear that the chemical history of litmus is far from complete. 
 
 What is known as tourncsol en drapeaux, litmus on rags, is almost solely used 
 in Holland to impart to the outer crusts of cheese a red stain, which preserves 
 it to some extent from decay and from the attacks of insects. It is a colouring 
 matter obtained from a kind of euphorbiaccous plant, the Croton tinctorium, 
 purposely cultivated chiefly at Grand-Gallargues, Departement du Gard, 
 France. The juice of the fruits, berries, and the young top shoots of 
 this plant is squeezed out, and clean coarse linen or other rags are steeped 
 therein. When dry the rags are hung up in or over vessels partly filled 
 with stale human urine, to which alum and lime have been added, or 
 the rags are simply covered with horse-dung ; this operation is locally 
 termed aluminadou. The rags are inspected, and the action of the am- 
 moniacal vapours carefully watched, because excess of that action would 
 destroy the colour. They are next dried, and are steeped a second time in 
 the juice of the plant, but now mixed with urine, after which they are again 
 dried in the sun, and exposed as much as possible to wind. The researches 
 of Dr. Joly,* of Toulouse, have proved that the colouring principle of the 
 
 * Joly, " Ann. dc Chim. et de Phys." | j], vi., i n. 
 
LITMUS. 
 
 383 
 
 Croton tinctorium pervades the entire plant at every time of its life, but is 
 chiefly present in the cellular tissue, wherein it occurs as a colourable body. 
 By the action of the oxygen of the air and rapid drying a blue colouration is 
 produced. When the fruit of this plant is immersed in twice its bulk of water 
 and heated to from 50 to 6o°, that liquid assumes a rather deep violet-blue 
 colouration, and deposits, on being evaporated, a beautiful azure-blue resinous 
 substance. Acids turn the colour of the aqueous solution to a yellowish red, 
 which is not rendered blue again by alkalies, but becomes greenish. By this 
 reaction, therefore, the " litmus on rags " is distinguished from the litmus of 
 commerce. The researches of Dr. Langdale and Dr. Martius made with the 
 juice of the plant just described have proved that it dyes, without the aid of 
 mordants, a violet-red upon wool, silk, and cotton tissues, and that this colour 
 may be rendered fast by steaming and the simultaneous action of ammonia 
 vapours, which, however, turn the colour more blue. The red colour of the 
 outer crusts of some kinds of Dutch cheese is due to the presence of some 
 lactic and butyric acids in that substance. No good substitute for this 
 " litmus on rags " for the last-named purpose has as yet ever been found. A 
 sum of £10,000 is annually paid by Dutch farmers, chiefly to the inhabitants 
 of Grand-Gallargues, for a commodity which, at first sight, no one would 
 take to be anything else but dirty rags, best suited for paper-making after 
 having been bleached. A portion of the rags, after having being used to rub 
 cheese with, are sent back, because it has been found that the old rags take 
 up and develope the colourable matter far more readily than new ones. The 
 violet-red colour prepared with the various kinds of lichens above mentioned 
 is not the only one which these plants are capable of yielding 
 
 M. Westring has made a series of dyeing experiments* chiefly with lichens 
 growing in Sweden, a country wherein these cryptogamic plants are found in 
 
 great abundance. Among the varieties he experimented with are : The 
 
 Pertustis ; sanguinarius, cinereus, rugosus, hcemaloma, subcorncus, tartareus 
 Lichen auritus, centrofugus, saxatilis, parictinus, omphalodes, saxicola, and 
 many others, all found on rocks or the barks of trees. In order to dye with 
 these lichens, M. Westring employs ammonia as the most active solvent, or a 
 mixture of lime (10 parts), with s \, of sal-ammoniac upon 1 part of lichen. 
 The addition thereto of a small quantity of common salt is sometimes useful, 
 especially for silk, which thus acquires more lustre. Mordants were not used, 
 as being found to do more harm than good. The colours obtained varied ac- 
 cording to the mode of extraction applied, also according to the temperature 
 and the quality of the water employed. 
 
 The colouring matter of some of the lichens can be extracted by steeping 
 them in cold water, and the liquid obtained is immediately suited for the dye- 
 beck; maceration in tepid water extracts the colouring matter from almost 
 all the lichens. The author obtained the following shades upon divers tissues 
 by more or less varying the treatment above described : — Grey, nut-brown, 
 more or less deep cinnamon, feuille morte, brick-brown, straw-yellow, olive 
 brown, and violet. Some lichens, among them certain species of Usnea, wall 
 lichen, yield to solvents a yellow principle, about which more will be said 
 when the yellow colouring matters are treated. 
 
 * " Annales de Chimie," vol. xii., p. 240. 
 

 384 
 
 DYEING AND CALICO PRINTING. 
 
 Alkanet. 
 The tinctorial matter now rarely used, known as alkanet, alkana, or canette', 
 is the root of a plant belonging to the natural order of the Borai'inacca:, called 
 Anchusa tinctoria. It grows wild in Greece, Asia Minor, Italy, and some por- 
 tions of Southern Germany. The root has been used in pharmacy and 
 perfumery, chiefly as a colouring matter. Its immediate tinctorial principle 
 was first isolated by M. Pelletier, who called it anchusine, or anchusic acid. 
 MM. Bolley and Wydler obtained it in a state of great purity, and called it 
 alkana red. They prepare it by first exhausting the previously dried and 
 sliced root with water, which dissolves and eliminates soluble vegetable prin- 
 ciples. The residue is then dried, and treated with alcohol ; the violet- 
 coloured alcoholic solution is acidified with hydrochloric acid, and evaporated 
 to dryness. The residue is next treated with ether, which dissolves the 
 colouring matter ; the ethereal solution is mixed and well shaken up with 
 water, whereby the colour is obtained in an insoluble state, and is dried after 
 the removal of the fluids by decantation. Dr. Lepage employs sulphide of 
 carbon instead of alcohol, and, after having removed the excess of the former- 
 named liquid by distillation, he treats the residue with a solution containing 
 2 per cent of caustic soda, and precipitates with a slight excess of hydrochloric 
 acid. The precipitate is separated by filtration, and, after having been 
 allowed twenty-four hours for settling, is well washed with water, and dried. 
 The material thus obtained is a deep red, brittle, resinous mass, insoluble in 
 water, soluble in alcohol and ether, to both of which it imparts a beautiful 
 reddish-violet colour. An alcoholic tincture of this root is used for colouring 
 the spirit of thermometers. The alcoholic solution is turned blue by alkalies, 
 and yields with bichloride of tin a violet precipitate. The same solution 
 yields with subacetate of lead a greyish-blue, and with acetate of alumina, at 
 a boiling heat, a violet-blue precipitate. 
 
 The pure alkana red is not at all affected by boiling its alcoholic solution, 
 but if the alcoholic tincture of the root be evaporated to dryness, without 
 having previously been acidulated with hydrochloric acid, there is a residue 
 left partly soluble in water, and imparting to it a brown colour, while what 
 remains undissolved colours ether greenish. This greenish pigment is, 
 according to Dr. Bolley, formed at the expense of the anchusine, which fixes 
 water and gives off carbonic acid. The precise composition of alkana red is 
 not known. Dr. Bolley states that its formula is C 35 H 40 08, but this is not 
 proved with certainty to be correct. 
 
 Anchusine appears to act as a feeble acid. Its hot alcoholic solution dyes 
 cotton, previously mordanted with alumina, a violet, and when iron mordants 
 are applied a grey. To 1 litre of alcohol (sp. gr. 0-849) 62 grms. of the alkana 
 red are used. The colours obtained are not fast, and are very readily affected 
 even by very weak alkalies and acids. 
 
 M. Hausmann, of Mulhouse, introduced the alkana red in calico-printing, 
 
 but it has never been used to any large extent, and is now altogether obsolete 
 
 for that purpose. The root and the prepared red are largely used for colouring 
 
 pomades and hair-oils, as a rouge for the complexion, and as a colouring 
 
 matter for lozenges. 
 
 Saffiower. 
 
 This substance, also known as wild saffron, is the produce of the Carthamus 
 tinctorins, an annual plant, a native of Southern Asia, and cultivated in India, 
 
SAF FLOWER. 
 
 385 
 
 also in some parts of Spain, Southern Germany, Italy, Hungary, Persia, 
 China, the Sunda Islands, South America, and Southern Russia. It resembles 
 the thistle : the petals of the plant are, when dried, what is known as 
 safflower, of which the following varieties occur in commerce : — 
 
 Egyptian Safflower. — Met with as strongly compressed, somewhat moist, 
 deep red-brown cakes, of a peculiar odour. It is packed in coarse canvas 
 bags, weighing from 320 to 350 kilos. It is cultivated partly near Cairo, 
 partly in Upper Egypt, and is chiefly imported into Trieste, Venice, 
 Leghorn, and Marseilles. 
 
 Spanish Safflower. — A pleasant-smelling, deep red, loose mass, very like 
 saffron. 
 
 Indian Safflower. — Occurs in commerce in the shape of small, flattened, 
 circular cakes, internally rose-red. It is packed in good canvas, exter- 
 nally covered by wicker-work, the packages weighing from 75 to 150 kilos. 
 
 Batavia Safflower. — Deep red, well-developed flowers, pressed in bales. 
 
 The Egyptian kind is the richest in colouring matter, containing nearly 
 twice as much as that from other countries ; yet the Indian and Chinese 
 safnowers are highly esteemed. The goodness of this substance may be 
 judged already by its external appearance, which should be of a fiery red ; a 
 dull redness is a proof of bad preparation. 
 
 Safflower contains three distinct colouring matters, viz., two yellow prin- 
 ciples, one of which is soluble in pure cold water or water slightly acidulated; 
 the other is only soluble in an alkaline licpior : thirdly, a red colouring matter, 
 carthamic acid, the only useful constituent. The quantity of the yellow colour 
 insoluble in water varies in the inverse ratio of that of carthamin (carthamic 
 acid). 
 
 According to M. Salvetat, safflower contains — Yellow colour, soluble in 
 water, from 26 to 36 per cent ; carthamin, from o - 3 to o - 6 per cent ; extractive 
 matter, 3-6 to 6-5 per cent ; albumen, from 1*5 to 8 - o per cent ; waxy matter, 
 06 to i*5 per cent; cellulose, 38*4 to 560 per cent: further, some pe&ic com- 
 pounds and silica, from 1 to 8'4 per cent ; oxides of iron and alumina, 0-4 to 
 i*6 per cent ; oxide of manganese, o - i to o - 5 per cent. 
 
 On treating safflower with cold water, the yellow colouring matter, the salts, 
 and albumen are removed. If the dye ware is treated with water acidulated 
 with acetic acid, filtered, and first acetate of lead and next ammonia is added, 
 the yellow colour is precipitated along with the lead salt. This precipitate is 
 washed, decomposed by means of dilute sulphuric acid, the sulphate of lead 
 separated by filtration, the liquid next evaporated in a retort, preferably in an 
 atmosphere of carbonic acid, but in every case as much as possible with 
 exclusion of air ; the residue afterwards treated with alcohol, and this 
 solution evaporated to dryness, yields, on being again treated with water, 
 the yellow colour, which, however, becomes rapidly changed by contact with 
 air. The aqueous solution is acid to test-paper, has a bitter taste, but the 
 yellow matter it contains does not possess any particular interest. Its elimi- 
 nation from the safflower intended to be used as a dye material is of great 
 importance, since the beauty of the colour is impaired by the presence of this 
 yellow matter, especially if animal fibres are to be dyed with the ware. 
 
 Canhamin, or carthamic acid, may be prepared in a pure state by making 
 use of its insolubility in water and solubility in alkaline liquids, such as solution 
 
 2 c 
 
WWMIWwmhiwuWWm 
 
 
 
 RHBRH9BS 
 
 386 
 
 DYEING AND CALICO PRINTING. 
 
 of carbonate, borate or phosphate of soda. For this purpose safflovver is first 
 freed, as far as possible, from its yellow colouring matter, by being well 
 washed with acidulated water, and is next treated with a dilute cold solution 
 of carbonate of soda (ordinary washing soda, 15 per cent) ; the mixture is 
 well squeezed, and to the clear bright yellow liquid thus obtained an acid is 
 added, whereby the carthamic acid, along with many impurities, is precipitated. 
 It would be almost impossible to free the carthamic acid from these foreign 
 substances, but this result is very readily brought about by immersing into the 
 alkaline solution, previous to the addition of an acid, a quantity of cotton- 
 wool. This material attracts, by a special action, the carthamic acid at the 
 moment it is set free by the addition of an acid ; and the cotton-wool may 
 first be washed in a weak acid, and next in water, and, lastly, again with a 
 weak alkaline liquid, which re-dissolves the carthrmin. After removal of the 
 cotton-wool, plenty of which should be used, it is re-precipitated by an acid, 
 very dilute citric or tartaric being the best. It falls down in the state of a 
 beautifully rose-red flocculent matter, which may be collected on a filter, 
 washed, and dried. In order to obtain a still purer material, the flocculent dry 
 substance should be dissolved in alcohol, and this solution, after having been 
 strongly concentrated, is poured into a large bulk of water, and the precipitate 
 thus formed is again collected on a filter and dried. Care should be taken to 
 avoid the use of too strong alkaline solutions,, nor should they be exposed to 
 air for any length of time, since this completely alters the colouring matter. 
 
 Carthamin in a pasty state, as obtained by the processes just described, is 
 met with in commerce suspended in water for direct use. The paste is dried 
 upon suitable vessels — porcelain saucers, plates of porcelain, or even upon 
 polished cardboard. The colouring matter, when dry, has a pecular cantha- 
 rides-like gloss and brilliancy, not unlike fuchsine ; the powder is beautifully 
 red, and is used also when mixed with French chalk and rubbed down with 
 water and again dried, as a rouge. 
 
 Carthamin is insoluble in ether, almost so in water, but soluble in alcohol, 
 to which it imparts a cherry-red. This alcoholic tincture dyes silk imme- 
 diately, no mordant being required. Carthamin is altered by boiling with 
 water and with alcohol ; it is soluble in concentrated sulphuric acid, forming 
 a red liquid, but water does not precipitate it from this solution. Nitric acid 
 and dilute sulphuric acid dissolve the carthamin, producing yellow liquids. 
 Carthamin is an acid, the alkaline carthamates being yellow or orange-yellow, 
 and yielding when in solution, on the addition of an acid, precipitates of car- 
 thamic acid. 
 
 Carthamate of ammonia yields, with bichloride of tin, a yellowish-brown 
 precipitate ; with perchloride of iron, a brownish-red ; and with bichloride of 
 mercury, a red precipitate. 
 
 According to Dr. Schlieper, the composition of the yellow matter of saf- 
 flower is CioH 2 oOi , while the formula of carthamic acid is, according to him, 
 Ci 4 HicO I4 . 
 
 Before the discovery of the aniline dyes, safflovver was very frequently used 
 to dye silk, wool, and even cotton fabrics. In order to apply it to cotton the 
 ware is first placed in canvas bags, and thoroughly washed with slightly 
 acidulated water, so as to eliminate all the yellow colouring matter as much 
 as possible. It is next treated with carbonate of soda (15 per cent of the 
 
SAFFLOWER. 
 
 387 
 
 crystallised soda of commerce dissolved in water), and'in this solution the 
 yarn or fabric to be dyed is immersed ; a slight excess of lime-juice is added, 
 to cause the precipitation and adhesion of the carthamin to the cotton. 
 Since silk and wool strongly attract the yellow colour, it is essential to elimi- 
 nate that substance entirely in order to ensure the full beauty of the safflower 
 shades. For that purpose the method of preparation already described for 
 carthamin is made use of, and the substance precipitated on cotton-wool is 
 frequently submitted to a second purification. Frequently the woollen and 
 silk tissues are first grounded (dyed a first time) with annatto or orchil, previous 
 to the dyeing with safflower. 
 
 The goodness and quality of safflower is estimated by a dyeing process with 
 a known weight of cotton : about 4 ounces of safflower will dye 1 lb. of cotton 
 cloth light pink; 8 ounces will dye a full rose-pink; and from 12 ounces to 
 1 lb. will dye it a full crimson. In order to take up this quantity the cotton 
 must be several times dyed in fresh solutions of the colouring matter. No 
 mordant is used for safflower, since none of the mordants known either 
 increase the affinity of the cloth for the colouring matter or give it any 
 greater stability. 
 
 The quantity of safflower required to dye silk is nearly the same as for 
 cotton, and the process is precisely similar. There is one peculiarity about 
 the dyeing with safflower which is worthy of special notice : in most other 
 cases the dyer is generally careful to have his dye-wares in a perfectly soluble 
 state for dyeing, but here the exceptional method of precipitating the colouring 
 matter from its solution, before the goods are entered for dyeing, is practised. 
 It is curious to speculate how the coloured particles can be so rapidly and so 
 completely attracted by the fibre as is found to be the case in practice. 
 
 The colours safflower yields, although the most beautiful and delicate 
 shades which the art of the dyer can produce, have the disadvantage of being 
 very unstable : nothing is easier than to detect safflower colours upon fabrics ; 
 the rose, pink, or crimson hue is at once turned yellow by a single drop of 
 alkali, and is destroyed by any further washing ; this property is actually made 
 use of now and then as a discharge, so as to produce a yellow pattern upon a 
 pink ground; weak acids do not affect the colours, but chlorine and sulphurous 
 acid destroy the colour at once. 
 
 Practical men generally prefer to extract the red colouring matter from saf- 
 flower — or, as it is technically called, to bleed it — by several successive appli- 
 cations of the solution of carbonate of soda, using weaker lye at first and 
 stronger ones afterwards. If the resulting liquids are kept separate, it will 
 be found that the first extract yields the brightest and purest colour, whilst the 
 subsequent solutions are progressively inferior. This principle has been taken 
 advantage of in dyeing, the goods being grounded with the last-obtained, or 
 most impure, carthamin, and finally " topped " or finished with the first, or 
 pure, portion of the colour. In tin's manner an unrivalled "bloom" and 
 brilliance are obtained. The best quality of liquid carthamin, or extract of 
 safflower, may be known by its colour approaching a scarlet. If it be crimson 
 the colouring matter is in a less minute state of division, and the shades^pro- 
 duced will be less bright. 
 
 The consumption of safflower has been lessened by the introduction of 
 saffranin, which is, in some works on dyeing, designated satnower-substitute. 
 

 ISBR8P88I 
 
 (388) 
 
 CHAPTER V. 
 
 COLOURING MATTERS OF VARIOUS ORIGIN. 
 
 Chica, Crajura, or Carajara. 
 
 A PIGMENT used by the Indians in Central America, and which is applied 
 to their bodies mixed with the fat of the alligator. The chica is obtained 
 from the leaves of the Bignonia chica, which the Indians boil for a long time 
 with water, decant the liquid, which contains a reddish-coloured fecula in sus- 
 pension, and add to the liquid some particles of the bark of a tree known as 
 aryane, which causes the precipitation of the colouring matter. This, when 
 dried, is a vermillion-red, tasteless and inodorous mass, specifically heavier 
 than water ; it soils the fingers, and assumes, when rubbed on the nail, a 
 metallic aspect. This substance is decomposed by heat without previous 
 fusion. 
 
 Chica is insoluble in water, but boiling alcohol, at 36 per cent, dissolves it, 
 becoming thus ruby-coloured. It is also soluble in ether. The alcoholic 
 solution is not precipitated by water unless heat is simultaneously applied. 
 Alkalies dissolve chica with a vinous-red colour, the solution being precipi- 
 tated by acids. Caustic potassa, ammonia, and carbonate of potassa dissolve 
 chica, the solutions exhibiting an orange or orange-red colour. Con- 
 centrated acetic and hydrochloric acids also dissolve this substance, yielding 
 a reddish-brown liquid ; chlorine turns its original colour to a bright brown ; 
 with dilute sulphuric acid it yields, when heated, an orange liquid, from which, 
 on coolin", a granular, orange-red mass is separated, while addition of ammonia 
 causes in the remaining liquid the formation of a deep purplish precipitate. 
 When chica is treated, in a sealed tube, with a mixture of any alkali and glucose, 
 it yields, by reduction, a bluish liquid, which becomes rapidly brown again on 
 exposure to air, and from which hydrochloric acid precipitates an orange-red 
 flocculent matter. Nitric acid attacks chica, converting it into a mixture of 
 picric, oxalic, anisic, and hydrocyanic acids. 
 
 According to M. Boussingault, chica — which, he says, contains no nitrogen 
 
 dyes C otton a yellowish-orange colour. Dr. Erdmann assigns to chica the 
 
 formula CsHsC^,— that is to say, it is an isomer of anisic acid. 
 
 Chica is rarely met with in Europe, but, from the results of experiments 
 made to ascertain its applicability as a dye, it was found that after treatment 
 with an acid, or with muriate of tin, it would dye very deep shades upon 
 wool ; and by treating it with acid, and washing the free acid away, it yields, 
 with mordanted cotton (alumina and tin mordants), shades very similar 
 to those produced by lac-dye. The colours are not so bright as those of 
 
COLOURING MATTERS OF FLOWERS. 
 
 389 
 
 cochineal, but are more permanent, and resist washing and exposure somewhat 
 better. 
 
 Colouring Matters Contained in the Sorgho. 
 
 Sorgho-Red. — The plant known as" durrha," Sorghum, or Sorgho sacchari- 
 fcrum,—a. native of Northern China, and belonging to the family of the Gramineas, 
 imported into Europe, and cultivated in some portions of Spain, France, and 
 Germany, since the middle of the year 1853, chiefly for the purpose of the 
 extraction of sugar, — contains several colouring matters, among which sorgho- 
 red or sorgho-carmine, obtainable from the interior {of the stems, after the 
 sugar has been removed, by means of the action of dilute sulphuric acid. 
 The pericarpium of the fruits or seeds contains, according to MM. Sicard, 
 T. Itier, and Joulie,* two different red pigments, viz., sorghotin and sorghin, 
 which are employed in China as dye-wares, yielding fast but not very bright 
 colours, somewhat like madder. M. Itier had in his possession pieces of the 
 dyed linen and cotton fabrics which he had seen prepared while in China, and 
 he also had sorgho-red (from the stem of the plant), and sorghotin and 
 sorghin, as sold in some parts of China ; but the larger portion of the mate- 
 rials brought by him and his co-travellers to Europe had been deposited with 
 the authorities at Paris, who (the revolution of 1848 intervening) seem to have 
 lost sight of these matters. The cotton dyed with a mixture of sorghotin 
 and sorghin, the cloth having been previously worked about in an emulsion 
 of a peculiar nature, exhibit at first sight no difference from Turkey-red, but it 
 is not so fast, — that is to say, does not stand acids, alkalies, &c, so well as 
 genuine Turkey-red. 
 
 Dr. Winter prepares from the stem of the sorgho a red colouring matter, by 
 leaving the stems, deprived of the greatest portion of their juice, to ferment, 
 piled up in heaps, until the colour has become red-brown ; the material is then 
 dried, and next cut up to small fragments and treated with water, and after- 
 wards with a weak caustic soda-lye. By this means the colouring matter is 
 dissolved, and, on addition of dilute sulphuric acid, precipitated. The dye 
 thus obtained is a flocculent matter, soluble in alcohol, in weak acids, and in 
 feebly alkaline liquids. By the aid of tin salts, as mordants, this pigment can 
 be fixed upon woollen and silk fabrics, yielding a bright crimson-red colour, 
 tolerably fixed and stable, withstanding light and washing with soap. The use 
 of the sorgho stems as a dye material, after the elimination of the sugar and 
 destruction of the saccharine matter retained in the stems, is in China rather 
 general. There is nothing precisely known as to the nature and origin of the 
 pigment thus applied as a dye. The bark of this kind of sorgho contains a 
 yellow-coloured matter, xantholein. 
 
 Rose-Red, Pink, Red, and Blue Colouring Matters of Flowers. 
 
 Although the brilliant colours of flowers are not useful for application 
 industrially, a few words upon these pigments are not out of place. 
 
 MM. Fremy and Cloez infer from their researches that there exist three 
 chief colouring principles in flowers, viz., cyanin, or a blue colouring matter; 
 a rose-red or pink colouring material, in reality the same as cyanin, but 
 
 * During the reign of King Louis Philippe these gentlemen were, among some others, sent 
 to China as an industrial ami scientific mission, and from some of their reports (never pub- 
 lished) portion;, of this article are made up. 
 

 9BBBB 
 
 390 
 
 DYEING AND CALICO PRINTING. 
 
 reddened by the acidity of the vegetable juice ; and lastly, two yellow principles, 
 viz., xanthin, insoluble in water, and xanthein, soluble therein. 
 
 Cyanin is best prepared from the petals of the violet or iris (Florentine), 
 by exhaustion with boiling alcohol, when the petals become decolourised and 
 the liquid assumes a beautiful blue tint. This alcoholic solution turns rapidly 
 to a yellowish-brown, in consequence of a reduction which takes place, but 
 when the liquid is agitated in contact with air the original colour is restored. 
 This reaction cannot be often repeated without causing the destruction of the 
 cyanin. The alcoholic liquid (solution of impure cyanin) is therefore evapo- 
 rated to dryness on the water-bath, and the residue is taken up with water, 
 which dissolves the blue colour, leaving resinous and fatty matters untouched. 
 The aqueous solution is precipitated by neutral acetate of lead, and the beau- 
 tiful green precipitate is, after having been well washed with distilled water, 
 decomposed by means of sulphuretted hydrogen ; the liquid freed from sul- 
 phide of lead by nitration is again evaporated to dryness, the lesidue taken up 
 with absolute alcohol, and the cyanin precipitated by means of ether. 
 Cyanin thus prepared is a non-crystallisable solid substance, soluble in 
 alcohol and water, insoluble in ether : acids, even if very weak, turn this sub- 
 stance red, while alkalies render it green ; reducing agents decolourise it, 
 but oxygen restores the colour. 
 
 The red colouring matter of flowers is extracted from the petals by a method 
 similar to that just described, and the material obtained exhibits all the cha- 
 racteristic properties of cyanin. 
 
 According to MM. Cloez and Fremy, the petals of red or rose-red flowers 
 are acid, while those of blue flowers are neutral. Some red flowers assume, 
 while fading, first a blue and next a green colour : this appears to be due to 
 the partial decomposition of a nitrogenous principle, whereby traces of am- 
 monia are set free ; other flowers, on the contrary, change from violet to red ; 
 a very rapid drying of red, pink, or rose-red flowers, whereby the carbonic 
 acid contained in some of them is eliminated, may cause the colours to 
 become blue. The rose-red, pink, violet, and blue colours of flowers seem 
 therefore due to the same substance, the differences of hues being brought 
 about by a difference in the quality of the vegetable juice. Scarlet flowers, 
 and such as exhibit a high red tint, are assumed to contain cyanin, mixed 
 with yellow matters. Some red flowers, those of the aloe species especially, 
 do not contain cyanin, but instead thereof a peculiar substance, which is 
 hardly soluble in water, insoluble in ether, but soluble in alcohol, and not acted 
 upon, not turned to any other hue of colour, by either acids or babeb. 
 
 Cyanin appears to be related to the roseo-cyanin formed by the action of 
 boric acid upon curcumin, the colouring principle of turmeric. Both sub- 
 stances are very unstable, and the reactions they exhibit are very similar. 
 The paracarthamin obtained by Dr. Stein, by the action of sodium amalgam 
 upon a mixture of quercetin and meletin, is also in its characters analogous 
 to cyanin. 
 
 Colouring Matters of the Malvaceae. 
 The petals of the plant known as Althcea rosea, belonging to the natural 
 order Malvaceae, contain a peculiar colouring matter, soluble in water and 
 alcohol, but insoluble in ether. The aqueous solutions of the petals, freed pre- 
 viously from the calix and stamens, exhibits a violet-red colour, which is turned 
 
SOORANJEE. 
 
 39i 
 
 crimson by the addition of acids and green by alkalies. The alcoholic tindture 
 of the leaves is purplish-red, and leaves, on evaporation, a deep red residue, 
 free from nitrogenous matter. Cotton mordanted with iron is turned blue or 
 bluish-black by an aqueous infusion of the petals. With an aluminous mor- 
 dant a violet-blue, and with tin mordants a bluish-violet, is produced. 
 Woollen fabrics, previously mordanted with bichloride of tin, assume a deep 
 violet, and when mordanted with iron a bluish-black or grey ; if mordanted 
 with antimonic acid salts, a bluish-violet is obtained : silk mordanted with tin- 
 salts takes a violet. 
 
 For calico-printing purposes the alcoholic extract: suits better than the 
 aqueous infusion. The colours produced are faster than those yielded by 
 logwood, but they do not stand clearing with soap. 
 
 The colouring matter is yet, and was formerly far more so, in great request 
 for the artificial colouration of wines. Latterly it has come into use as a dye- 
 ware, and is chiefly so applied in Germany, and more particularly in Bavaria. 
 
 Sooranjee, Root of the Morinda citrifolia. 
 
 This ware was first imported into Glasgow from India, some years ago : it 
 occurs in pieces of from 2 to 8 centimetres in length, and from 5 to 10 milli- 
 metres thick. Externally it is brown, internally yellow ; the pigment, or 
 colouring matter, is exclusively concentrated in the bark ; its colour is orange- 
 yellow, and it has been named morindin. 
 
 The morindin is extracted from the root by exhausting with boiling alcohol : 
 on cooling, the colouring matter is deposited as an impure flocculent material, 
 mixed with a red substance. This crude material is purified by repeated re- 
 crystallisation, first from alcohol at 50 per cent, and finally from stronger 
 alcohol acidulated with hydrochloric acid. Thus obtained the substance 
 forms satin-like, needle-shaped, yellow crystals. Morindin is sparingly soluble 
 in cold water, more readily in boiling, but is deposited, on cooling, as a gelati- 
 nous mass. It is sparingly soluble in alcohol when cold, but readily when 
 boiling, and best in a weaker spirit ; it is insoluble in ether. The aqueous 
 solutions are coloured orange by alkalies ; lime and baryta water yield red 
 precipitates, while acetate of lead forms a crimson precipitate : a mixture of a 
 few drops of ammonia added to perchloride of iron causes a brown precipitate 
 in the aqueous solution, while ammoniated alum yields a reddish-yellow pre- 
 cipitate. Morindin dissolves in concentrated sulphuric acid with a deep 
 purple-red colour; the solution, after having been kept for twenty-four hours, 
 yields, on addition of water, a yellow precipitate, insoluble in water, which 
 re-dissolves in ammonia with a violet colouration. 
 
 If submitted to the action of heat, morindin first fuses and then enters into 
 ebullition, emitting beautiful orange vapours, which condense to beautiful red 
 needle-shaped crystals, insoluble in water, but soluble in alkaline liquids, with 
 a violet colour. This substance, which Dr. Anderson calls morindon, seems 
 to be the same as that formed under the influence of sulphuric acid, The 
 ammoniacal solution of morindon yields, with alum, a red lake, and gives, 
 upon the addition of baryta water, a blue precipitate. Morindin is dissolved 
 by cold nitric acid, and decomposed by that liquid at boiling temperature. 
 
 Prof. Rochleder thinks that morindon is identical with ruberythric acid, and, 
 according to him, morindon is alizarin, but this view is not confirmed by 
 

 BB 
 
 392 
 
 DYEING AND CALICO PRINTING. 
 
 Dr. Anderson's analysis, which should percentically contain — carbon, 65-81 ; 
 hydrogen, 4/18 : these figures agree very nearly with those which Dr. Schi.it- 
 zenberger found for purpurin, viz., carbon, 65-6; hydrogen, 3-2. 
 
 According to Dr. Anderson, the colouring matter of sooranjee does not dye 
 fabrics mordanted as usual, but cotton prepared for Turkey-red assumes, when 
 placed in a bath of the ground-up sooranjee, a deep brownish-red colour, very 
 fast, but not at all bright. 
 
 The Hindoos have used sooranjee for centuries. They prepare an emulsion 
 of sesam oil and carbonate of soda, steep the tissue therein, dry it in the air, 
 and next steep it in a mixture of sesam oil and pulverised sooranjee root. 
 The fabrics thus take a solid red. We ought to observe that Mr. Bancroft and 
 others, who have examined, in the beginning of this century, a substance also 
 brought from India, and bearing the same name, found no difficulty in dyeing 
 common mordanted cloth with it. The sooranjee is also known to, and used 
 by, the Javanese, and Dr. Rost van Tonningen states that it dyes as well as 
 madder, but the shades are neither so fast nor so brilliant. 
 
 Since there is in the India Museum (Whitehall, India Office) a very large 
 number of samples of this substance, which apparently differ, at sight at 
 least, while the Indian names vary, which may arise from the diversity of 
 dialects and languages of Hindostan, there is a field of research open in this 
 direction. 
 
 CEnolin, or Red-colouring Matters of Wine. 
 A few words on the substance just named may find a place here. The 
 subject has been studied by Dr. Glenard,* who obtained the colour from 
 genuine red wine, by precipitation with basic acetate of lead. The blue pre- 
 cipitate is well washed, dried at ioo°, put in a displacement apparatus, and while 
 therein treated with anhydrous ether previously impregnated with dry hydro- 
 chloric acid gas. The ether which passes through takes up a brown matter, 
 and the precipitate is washed with ether until all acid reaction ceases. The 
 residue of the precipitate, which has a deep red colour, is treated with alcohol 
 (sp. gr. 0*849), which assumes a bright red. This tincture is concentrated by 
 evaporation in a water-bath, and when reduced to a small bulk water is added, 
 which causes the precipitation of a red flocculent substance, insoluble in 
 ether, difficultly soluble in water, soluble in alcohol, insoluble in benzol. 
 When boiled with water for some time this substance turns brown, its compo- 
 sition is changed, and it loses its solubility in alcohol. Hence it is that when 
 wine is evaporated to dryness it gives, when taken up with alcohol, a dirty 
 brownish colour to that fluid. 
 
 The weak alcoholic solutions of the pure red colouring matter exhibits the 
 following reactions : — Chlorine destroys the colouring matter, converting it 
 into a yellow substance ; potassa solution turns the colour first blue, next 
 brown ; lime-water yields a precipitate of dead leaves colour (feuille worte) ; 
 bicarbonate of soda, a blue colouration ; chloride of calcium, a blue colouration ; 
 alum turns the colour to light red ; with hydrochloric acid, no change ; nitric 
 acid converts the substance into a yellow flocculent matter; acetate of lead, 
 
 * "Journal de Pharmacie et de Chimie," vol. xxxv., p. 113. " Comptes Rendus de l'Academ. 
 des Sciences," vol, xlvii., p. 268 ; vol. lviii., p. 268. ■' Annales de Chimie et de Physique," [ 3], 
 vol. liv., p. 366. " Repertoire de Chimie Appliquee," vol. iv., p. 328; vol. i., p. 32. " Repertoire 
 de Chimie Pure," vol. ii., p. 306. 
 
YELLOW VEGETABLE COLOURS. 
 
 393 
 
 blue precipitate; nitrate of lead, violet-red precipitate; acetate of copper, 
 chestnut-brown precipitate. 
 
 According to Dr. Glenard the formula of cenolin is Ci H I0 5 . Young 
 wines contain, moreover, according to Dr. Filhol, a peculiar blue colouring 
 matter, soluble in acetic and butyric ethers, yielding bright, beautiful, violet- 
 blue solutions, which, by the addition of some ammonia, become first green 
 and next brown. The chemist just named considers that this substance is 
 identical with cyanin as met with in many flowers. 
 
 The colouring matter of wine is not industrially employed as a dye, but its 
 properties are of importance, since they may assist in detecting frauds and be 
 useful in medico-forensic researches. Genuine wines are often artificially 
 coloured, but in the wine-growing countries this is done by the addition to the 
 fermenting must of a peculiar kind of grapes, of a very deep blackish-blue 
 colour, purposely cultivated— as, for instance, at Lespane and many other 
 localities— for its colouring qualities. 
 
 Among the vegetable colours we notice with a word the following : — 
 
 The red cabbage colour, probably cyanin (" Dingler's Polytechnisches 
 Journal," vol. xvi., p. 268) : this material becomes green by alkalies, 
 and was formerly in use as a test for them in chemical laboratories. 
 The red matter of the red poppy flower (" Dingler's Pol. Journ., vol. xxii., 
 
 p. 271). 
 The so-called dragon's-blood, a red-coloured resin, the produce of a kind 
 of palm tree, a native of Sumatra and Borneo (" Journal de Pharmacie," 
 vol. xvii., p. 225 ; " Annalen der Chimie und Pharmacie," vol. xliv., 
 p. 328 ; " Comptes Rendus," vol. xvii., p. 503 ; vol. xix., p. 505). 
 The Lithospermum rose-red (" Repertoire de Chimie Appliquee," vol. i., 
 
 p. 209 ; " Archiv. der Pharmacie," vol. cxlvi., p. 278). 
 The peculiar red of the red cinchona barks. 
 The bark of the Lithospermum arvcnse yields, when treated with alcohol, a 
 deep red-coloured resinous substance ; the alcoholic tincture of deep red colour 
 turns blue upon the addition of alkalies. This resin is soluble in strong sul- 
 phuric acid, and exhibits great analogy with anchusin, but is distinguished 
 from it by the colour of its ethereal solution, which is blue, and not red, as is 
 that of anchusin. 
 
 Yellow Vegetable Colours. 
 Of the colours met with in the vegetable world none is so abundant and 
 widely distributed as the yellow, which occurs in almost all plants to a greater 
 or less extent, while the researches of Dr. Thudicum on lutein, of which the 
 following is a brief abstract, prove the identity of some of the yellow 
 colouring matters of the vegetable and animal kingdom : — 
 
 By lutein Dr. Thudicum understands a yellow crystalline substance occur- 
 ring in various parts of animals and plants, as, for instance, the corpora lutea 
 of the ovaries, serum of blood, yolks of eggs, in seeds, as maize (Indian corn), 
 in annatto, in carrots, and the stamens and petals of a great many flowers. 
 Lutein is easily soluble in alcohol, ether, and chloroform, insoluble in water- 
 these solutions are yellow, but that in chloroform, when concentrated, has an 
 orange-red colour. The spectrum of its solutions is distinguished by great 
 brilliancy of the red, yellow, and green part, and by three absorption bands, 
 which are situated in the blue, indigo, and violet part of the spe&rum. The 
 
mm BH H 
 
 EEEEEEEEI 
 
 ■ 
 
 394 
 
 DYEING AND CALICO PRINTING. 
 
 crystals of lutein are apparently rhombic plates, of which two or more are 
 always superposed in a curious manner. The crystals are microscopic, yellow 
 when thin, orange to red when thick, and have no resemblance to any other 
 known animal or vegetable substance. Lutein combines with few substances, 
 mercury-acetate being, perhaps, the only reagent by which it is immediately 
 and completely precipitated as a yellow deposit ; mercury-nitrate produces a 
 yellow precipitate which, on standing, becomes white. Nitric acid poured 
 over the crystals produces a blue colour, which immediately passes into 
 yellow. The blue is not produced when nitric acid is added to either the 
 alcoholic, ethereal, or chloroformic solution of lutein, but appears with 
 the acetic acid solution, and disappears again rapidly. Lutein has great 
 affinity for fatty matters and for albumen. 
 
 In order to prove further the wide distribution of yellow colours, we quote 
 the names of those vegetable substances which contain a yellow colour in 
 sufficient quantity to make them applicable as dye-wares; these are: — 
 Quercitron bark (from the Quercus tinctoria) ; true or old fustic (Morns tinctoria, 
 or Broussonetia tinctoria ; young fustic, the wood of the Rhus cotinus ; the 
 bark, twigs, and berries of the dyer's buckthorn, obtained from various species 
 of the Rhamnus, as for instance, frangnla, cathartics, saxatilis, infectoria, 
 oleoides ; the Chinese yellow, Gardenia grandiflora ; saffron, Crocus sativus ; 
 safflower, Carthamus tinctoria , the fruit and leaves of the Bixa orellana (the 
 annatto plant) ; rhubarb root ; wall lichens, Pannelia parietina ; weld, the 
 Reseda luteola, entire plant ; the root of the Berberis vulgaris ; turmeric root 
 (Curcuma tinctoria) ; the aloe juice ; and, lastly, a host of yellow-coloured 
 flowers, some roots, among them the Eschscholtzia, the common carrot, and 
 the mulberry-tree root, and also the shells of various nuts and other vegetable 
 products. 
 
 Viewed as a pure immediate principle the yellow pigment obtained from 
 these several plants does not prove to be identical in composition ; but it 
 should not be thought, on the other hand, that every species of plant contains 
 a peculiar corresponding colouring matter. It has been proved that many of 
 the yellow pigments obtained from the plants above named are very similar to 
 each other as far as their chemical character is concerned, though their 
 physical properties may differ widely. The yellow colouring matters met 
 with in quercitron bark, Persian berries, fustic, young fustic, weld, and some 
 other plants, are very similar both in their chemical and physical characters ; 
 as. a result thereof the mode of their practical application and fixation on 
 textile fibres closely corresponds, and the only difference in the shade of the 
 colours produced is the greater or less brightness, a tone verging more or 
 less towards the orange, and the degree of fastness. It will thus render our 
 task easier, both as regards the chemical history of the yellow pigments, and 
 the mode of their application on the large scale, if we include these under the 
 head quercitron yellows. 
 
 These yellows as met with in plants are frequently soluble, crystallisable 
 glucosides, which on being boiled with dilute mineral acids are split up into 
 glucose or some analogous substance, and a new body, generally of a deeper 
 colour, and less soluble in water, but very readily so in alcohol, and also 
 crystallisable. This derivative, which while combined with the glucosic 
 molecule is to be considered as the real cause of the colour of the pigment, 
 
QUERCITRON. 
 
 39: 
 
 may also be met with in free state. Its properties rather differ in different 
 plants ; its chemical features are simultaneously those of a weak acid, which 
 can enter into combination with alkalies and metallic oxides, and of a poly- 
 atomic alcohol approaching to phenol. The alkaline solutions are orange or 
 brown-coloured, and do not change perceptibly when left in contact with air; 
 heated along with ammonia, contact of air being excluded, an amide is 
 formed remarkable for its ready oxidation in contact with air. 
 
 Hlasiwetz has proved that when fusing caustic potassa or sodium amalgam ads 
 upon an alkaline solution of this body it is converted into a saccharine matter 
 and phloroglucin (CgHeC^), frequently accompanied by a colourless acid. 
 When sodium amalgam is placed in contact with an acidified alcoholic solution 
 of this substance it is molecularly changed and converted into a red isomeric 
 principle. 
 
 Anhydrous acetic acid heated to 140 with this quercetric yellow converts 
 it into an acetic derivative, the hydrogen of the orginal body being partly re- 
 placed by acetyl. The quercetric glucosides or the yellow-coloured body 
 obtained therefrom can only be fixed on textile fibres by the aid of metallic 
 mordants. With hydrate of alumina a yellow shade is obtained, with iron 
 mordants olives, and with oxide of tin yellows or oranges. Quercitron bark 
 is the inner bark of some species of trees belonging to the natural order of 
 Amentaceas, and botanically known as Quercus nigra, digitata, trifida, and 
 tinctoria. The Quercus nigra, or black oak, so called because the outer 
 epidermis of the bark is black, is a native of the middle and southern states 
 of the U.S. of America. It is a tree attaining a height of from 25 to 30 
 metres, abundantly met with in the forests of Pennsylvania, Georgia, and 
 Carolina. Quercitron bark, as met with in commerce, is a mixture of fibres 
 and fine powder of a yellow or buff colour. Its preparation is very simple; 
 the bark previously deprived of its black epidermis is ground under millstones, 
 and the fibrous portion (which is the least valuable) is sometimes separated 
 by means of sieves. Three kinds of quercitron are distinguished in commerce, 
 imported from Philadelphia, New York, and Baltimore, the first being generally 
 preferred. 
 
 The celebrated Bancroft was the first to apply (1775) this now highly ap- 
 preciated dye-ware. The decoction of quercitron exhibits an orange-yellow 
 colour. If exposed to air it very slowly deposits its colouring matter 
 (quercitrin or quercin) in a crystalline state. After standing for a long time 
 thus exposed the colour turns brownish red, and at last it becomes a thick 
 clotted mass. Its properties are : odour of the oak bark decoction, like that 
 of freshly charged tan pits; taste, bitter astringent; readion, acid to test- 
 paper ; the addition of alkalies and alkaline earths deepens the colour of the 
 decoction, the latter simultaneously producing a reddish flocculent precipitate. 
 With the undermentioned substances the deco&ion of quercitron yields the 
 following reactions : — 
 
 Alum, a very slight precipitate; proto and bichloride of .tin, acetate of lead, 
 acetate of copper, chloride of barium, nitrate of silver, yield yellow precipitates 
 verging upon red or olive ; salts of iron, a green colouration and olive pre- 
 cipitate ; mineral acids render the colour of the decoction brighter, and produce 
 a flocculent precipitate ; acetic acid merely brightens the colour ; solution 
 of gelatin gives a flocculent precipitate. The more interesting immediate 
 

 m 
 
 999999 9999999999 
 
 396 
 
 DYEING AND CALICO PRINTING. 
 
 principles of this decoction are — (1) a peculiar tannic acid, called quercitannic 
 acid, which colours the iron salts like ordinary tannic acid, hut does not, 
 like that acid, yield gallic acid ; (2) the quercitrin or adtive principle. 
 
 In order to estimate the tinctorial value of quercitron (or, as it is commonly 
 called by dyers, " bark "J a piece of previously mordanted cotton is dyed with 
 the ware to be tested, the operation being conducted as described under 
 madder, and the results compared with those obtained simultaneously with a 
 sample of quercitron known to be of good quality. A pale yellow colour of 
 the quercitron may be taken as an indication of good quality. A few grammes 
 of the sample may be burned off in a platinum crucible as a test for mineral 
 adulterations, while the moisture also should be estimated by drying the 
 sample at 120 . 
 
 Colouring Matters Contained in Quercitron. 
 
 1 part of quercitron boiled for a quarter of an hour with 10 parts of water 
 deposits, after some days' standing, a crystalline body, named quercitrin by 
 M. Chevreul.* Dr. Bolley describes this principle as quercitric acid, and pre- 
 pares it by exhausting the quercitron of commerce in a displacement apparatus 
 with alcohol at 84 per cent. The tannin (ordinary tannic acid) contained in 
 the solution is first removed by gelatin, and after filtration the solution is 
 evaporated to dryness, yielding a crystalline mass, which is purified by 
 several re-crystallisations from alcohol. f Some varieties of quercitron con- 
 tain a substance soluble in cold water, and capable of being split up at 60°, in 
 the presence of water, into sugar and quercitrin. 
 
 M. E. Schlumberger once accidentally when working upon such quercitron 
 succeeded in extracting quercitrin therefrom with the greatest ease by simply 
 heating to 60° the cold aqueous infusion of the bark. The liquid when so heated 
 became turbid, and deposited the quercitrin in beautiful mother-of-pearl-like 
 shining crystals, which were nearly chemically pure. It rarely happens that this 
 phenomenon can be reproduced with the bark as imported; probably the result 
 would be more satisfactory with the fresh bark, since it is not unlikely that 
 the material known as flavin, and manufactured in the United States, 
 although chiefly consisting of quercitrin, is produced by a similar process 
 to that employed by M. Schlumberger. Any chemist desirous to prepare 
 quercitrin in quantity will do best to operate on flavin. It is only 
 necessary to boil it with a large quantity of water, and to filter while boiling 
 hot ; the liquid on cooling deposits quercitrin in a crystalline state, and 
 almost perfedHy pure. Q".erctrin is hardly soluble in cold water, but 25 parts 
 of boiling water dissolve it ; it is also soluble in alcohol, but not well in 
 ether. Ammonia and the aqueous solutions of caustic alkalies dissolve 
 quercitrin readily, the colour of the solutions being a greenish yellow. The 
 ammoniacal solution is rapidly oxidised by the aclion of air, and turns brown. 
 Baryta water causes in the aqueous solution of quercitrin a reddish yellow 
 precipitate ; with alum solution a beautiful yellow colour is produced ; the 
 acetates of lead and copper and the chloride of tin yield flocculent yellow 
 precipitates ; persulphate of iron turns the colour olive-green, and causes a 
 
 * Chevreul, "Lemons de Chimic Appliquee a la Ttinture, " a valuable and now very rare 
 book; for years out of print. 
 
 1 Bolley, " Annalen der Chemie und Pharmacie," xxxvii., 101. 
 
QUERCITRON. 
 
 397 
 
 gradual precipitation. Nitric acid colours quercitrin orange-red, and 
 concentrated sulphuric acid dissolves it. Quercitrin is a bright yellow 
 crystalline, inodorous powder, of a somewhat bitter taste and feebly acid 
 reaction. Under the lens the powder appears as small rectangular tubular 
 crystals. As obtained by the cooling of an aqueous solution quercitrin has 
 the appearance of a mother-of-pearl-like shining bright yellow substance. 
 When submitted to heat it yields a yellow sublimate, and leaves an abundant 
 residue of charcoal. There exists some uncertainty as regards the proper formula 
 of quercitrin ; several which have been proposed agree each with the results of 
 the elementary organic analysis, but since certain experimenters have over- 
 looked what was proved by Dr. Hlasiwetz, that quercitrin does not become 
 completely anhydrous below 200 , retaining a part of its water of crystallisation 
 nearly to that temperature, it is conceivable that there exist discrepancies in 
 the centesimal results of the elementary analysis. Quercitrin is a glucoside 
 capable of being split up into a kind of sugar, and a yellow principle, 
 "quercetin;" the formula to be assigned to quercitrin will therefore to a 
 certain extent, and within the limits of a more exact chemical analysis, 
 depend upon the formula of quercetin, and since we cannot discuss the 
 constitution of the latter as yet, we give here the centesimal results of 
 those analyses of quercitrin which appear most correct : — 
 Dried at 200 
 
 MM. Hlasiwetz 
 and Pfaundler. 
 
 Incompletely dried. 
 
 MM. Zwenger 
 and Drouke. 
 
 Carbon .. 56-0 562 55-7 54-1 52^4 
 
 Hydrogen 4-6 4-5 5-2 5-2 4-9 
 
 According to the researches of M. Rigaud,* an aqueous solution of 
 quercitrin acidified with sulphuric acid and boiled becomes turbid, and de- 
 posits even while yet hot an abundance of a flocculent material far more 
 deeply yellow than quercitrin, and nearly insoluble in boiling hot water. 
 This phenomenon is best seen by heating together pure quercitrin and water, 
 to which one-tenth of sulphuric acid is added ; at a moment when the tem- 
 perature is sufficiently high the quercitrin becomes dissolved, and a moment 
 after the liquid turns suddenly intensely yellow, next turbid, and then 
 deposits flakes of quercetin. The liquid from which the quercetin has 
 been separated by filtration is first treated with carbonate of baryta to 
 eliminate the sulphuric acid, and is, after filtration, evaporated, thus yielding 
 a syrup, which, according to Zamminer, may become a crystalline mass. The 
 sugar is not possessed of rotatory power; it reduces alkaline solutions of 
 salts of copper, and its composition corresponds to glucose (C6H I2 0c). 
 
 Hlasiwetz and Pfaundler have come to other results; the evaporation of 
 the syrup yielded them after a few hours a beautiful crystalline substance, 
 which crystallographically agrees with saccharose or cane-sugar ; these 
 crystals dissolve at 18 in 2*09 parts of water, and also in absolute alcohol ; 
 they taste sweeter than glucose, and deflect the plane of polarisation to the 
 right (specific deviatory power = o - 0763°). This sugar is incapable of fermen- 
 tation, and its formula is C6H I2 5 + H 2 0. The last molecule of water may 
 be eliminated at no ; it reduces the cupreous test liquor, and fuses at 107°. If 
 treated with a mixture of concentrated nitric and sulphuric acids, the sugar just 
 
 * "Annalen der Chemie und Pharmacie," xc, 283. 
 
hh mm Hi BBHani 
 
 
 398 
 
 DYEING AND CALICO PRINTING. 
 
 mentioned yields a body, C<5 ( N( ^Mo s . This sugar is isomeric with 
 
 mannite and dulcite, and has been named isodulcite. 
 
 Hlasiwetz and Pfaundler state that there exist various kinds of qucrcitrin, 
 which differ by the nature of sugar in combination, while the composition of 
 the other constituent, the quercetin, is constantly the same. Quercetin, first 
 discovered by M. Rigaud as the product of the splitting up of the quercitrin, 
 is, according to Dr. Bolley, also found either isolated or in a glucose com- 
 bination in other plants.* He states that Persian berries yield, when treated 
 with ether a yellow colouring matter, which, on being purified, first by the 
 evaporation of the ether, next precipitated by water, then taken up by alcohol, 
 and slow evaporation of this solution after addition of water, yields a substance 
 exhibiting all the characters as well as the composition of quercetin. 
 
 Schiitzenberger and Berlechi state in reference to this assertion of Bolley, 
 that a full investigation of rhamnetin, obtained by the splitting up by means 
 of sulphuric acid of the rhamnin (the coloured glucoside of the Persian 
 berries), has proved that rhamnetin, however much resembling quercetin, 
 cannot be confounded therewith, and the question therefore is, whether the 
 substance taken for quercetin by Dr. Bolley is not in reality rhamnetin. 
 
 Rochleder and Hlasiwetz have extracted quercetin from the flower-buds of 
 the Capparis spinosa, and Stein has found it in the immature flower-buds of 
 the Sophora japonica. Rochleder has proved the existence of quercetin in 
 the bloom and ripe fruits of the horse-chestnut (Msculus hippocastanum).\ 
 The yellow pigment found by Dr. E. Schunck in the leaves and stems of the 
 buckwheet plant (Polygonum fagopyrum), is identical with rutin. According 
 to Bolley and Mylius, the yellow pigments of fustic ought to be considered as 
 quercetin.]: Hlasiwetz thinks that thuyin of Kawalier|| does not differ from 
 quercitrin, while the meletin obtained by Stein by spitting up melin also 
 appears to be quercetin. The robinin obtained by Zwenger and Drouke 
 from acacia flowers (Robinia pseudo-acacia) differs from quercetrin, but may 
 be like that substance split up into sugar and quercetin. § Robinin is also 
 found in the flowers of the Carvus masciila.% These instances are quoted 
 here to prove the wide distribution of quercetin and its glucosides throughout 
 the vegetable kingdom. When pure, quercetin is a lemon-yellow, crystalline 
 powder, of a far richer shade than quercitrin. It is tasteless and colourless, 
 insoluble in cold, and nearly so in boiling, water, and it is thereby distinguished 
 from rhamnetin, which deposits from a litre of its boiling solution a weight 
 of 0-653 grm. on cooling, while the quantity of quercetin so deposited is 
 quite insignificant. Quercetin is very soluble in alcohol, and cannot be 
 readily obtained from such a solution in a crystalline state, except by the 
 addition of water. 
 
 Quercetin is readily dissolved by boiling acetic acid and solutions of alkalies, 
 the liquor in the latter case having an orange-yellow tint ; acids precipitate 
 
 * " Annalen der Chemie und Pharmacie," cxv., 54. 
 + " Chemisches Centralblatt," new series, iv., 162. 
 Vienne," xxxiii., 365. 
 
 } Schweitzerische, " Polytechnische Zeitschrift," ix., p. 22. 
 U " Comptes Rendus de l'Academie de Vienne," xxix., p. 10. 
 § " Ann. der Chem. und Pharmacie," supplementary vol. i., 257 
 IT " Journal fiir Prakt. Chem." lxxxviii., 280. 
 
 ' Comptes Rendus de l'Academie de 
 
QUERCETIN. 3gQ 
 
 the quercetin from these solutions unaltered. The ammoniacal solution of 
 quercetin becomes brown in contact with air; the alcoholic solution yields, 
 with lime and baryta waters and solution of acetate of lead, orange precipi- 
 tates. Quercetin yields with chloride of tin an orange colour, and a green 
 with perchloride of iron. When quercetin, suspended in water, is submitted 
 to the action of chlorine it becomes oxidised and dissolves ; the dry quercetin 
 yields, under the influence of chlorine, an orange matter, probably a substitution 
 product ; nitric acid, fuming and common, attacks quercetin, red fumes being 
 given off. The alcoholic solution of quercetin is decolourised and reduced by 
 nascent hydrogen ; when acted upon by concentrated sulphuric — or, better yet, 
 fuming sulphuric — acid, quercetin is dissolved, giving rise to the formation of 
 a yellow sulpho-acid, soluble in water, of an acid taste, and capable of directly 
 dyeing woollen tissues yellow without the aid of a mordant. 
 
 Quercetin is not even decomposed by a temperature of 350 C, and at 
 higher temperatures is destroyed without any volatilisation. It retains its 
 water of crystallisation most tenaciously ; 100 parts of air-dried quercetin 
 lose, at 120 , ii'5 parts of water, but it requires a temperature of 200 to 
 eliminate the last traces. Quercetin, dried at that temperature and analysed, 
 yielded, according to Hlasiwetz and Stein, centesimally — Carbon, 6o*o and 
 60-3; hydrogen, 37 and 3-9. Guided by his experiments on the splitting up 
 of quercetin into phloroglucin (C6H6O3) and into quercetic acid (Ci 5 H I0 7 \ 
 he assigns to quercetin the formula C 2 jHi%Oi 2 (centesimally = C, 607 ; H, 3*4). 
 Schiitzenberger and Berteche have proposed for quercetin the formula CuHsOj, 
 as better agreeing with the results of the analysis (centesimally =C,6o*o; H,3'8), 
 and that formula makes quercetin the lower homologue of rhamnetin 
 (C I2 H, 5 ). While heating quercetin with anhydrous acetic acid (CeH 4 3 ) 
 the two last-named chemists obtained a crystalline acetic derivative, of the 
 formula CnHsC^, containing 3 01-4 atoms of acetyl (C 2 H 3 0) substituted for 3 or 
 4 atoms of hydrogen. 
 
 Quercetin can combine with potassa, soda, and oxide of zinc : a hot and 
 concentrated solution of 1 part of quercetin and 3 parts of carbonate of potassa 
 deposits, on cooling, fine needle-shaped crystals, very readily changeable, 
 which may be dried between folds of blotting-paper, but cannot be again re- 
 dissolved in water without undergoing decomposition, unless carbonate of 
 potassa be added. The crystals are even somewhat altered by drying in the 
 air at common temperatures. When 5 parts of carbonate of soda and 1 part 
 of quercetin are taken, the corresponding soda compound is obtained. Ac- 
 cording to Hlasiwetz the formula? of these compounds are — C 27 Hi80 12 K 2 ; 
 C 27 H!80i 2 Na 2 0. Dr. Schiitzenberger prefers the formulae CnH 7 K0 5 and 
 Cj,H 7 Na0 5 . 
 
 Hlasiwetz and Pfaundler found, on thoroughly investigating the action of 
 caustic potassa upon quercetin, the production of three substances, viz. 
 phloroglucin, quercetic acid, and paradatiscetin, obtained by adding to a 
 solution of 3 parts of potassa in 1 part of water put into a silver dish, 1 part 
 of quercetin, and rapidly evaporating that mixture to dryness. In order to 
 separate these bodies the alkaline mass is first dissolved in water, and next 
 neutralised with hydrochloric acid. By this operation the first two bodies 
 remain in solution, but the paradatiscetin, still mixed with some quercetin, is 
 precipitated in an impure state ; the liquid is next filtered, and, after the 
 

 ■ 
 
 400 
 
 DYEING AND CALICO PRINTING. 
 
 addition thereto of the quarter of its bulk of alcohol, is repeatedly shaken up 
 with ether, which dissolves phloroglucin and quercetic acid. The liquids 
 having been allowed to settle, the upper layer (ether) is decanted off and 
 evaporated to dryness, the residue is taken up with water, and the solution 
 precipitated with basic acetate of lead. The filtrate yields, after treatment 
 with sulphuretted hydrogen, to eliminate the lead, and removal of the sulphide 
 of that metal, on concentration, crystals of phloroglucin, C6H6O3, a kind of 
 saccharine matter related to orcin, and also discovered by Hlasiwetz among 
 the products of decomposition of phloretin. The plumbic precipitate is first 
 washed, next suspended in water, and decomposed by a current of sulphuretted 
 hydrogen, and the resulting liquid, after filtering off the lead compound, is 
 concentrated either by evaporation in vacuo or by gentle heat in a current of 
 hydrogen gas. The crystalline matter obtained is purified by re-crystallisa- 
 tion and decolouration over animal charcoal. The silky-looking needle-shaped 
 crystals thus obtained are quercetic acid, — a weak acid, hardly soluble in 
 cold water, soluble in boiling water, alcohol, and ether; the acid slightly 
 reddens blue litmus-paper, and has an astringent taste ; it reduces nitrate of 
 silver, and imparts to perchloride of iron a blue colour, while the acid 
 assumes in the presence of alkalies a magnificent purple-red. Sulphuric acid 
 dissolves quercetic acid, yielding a red-brown solution, from which water 
 precipitates a red flocculent matter, soluble in alkalies with a purple colour. 
 The formula of quercetic acid is, according to Hlasiwetz, C I5 H I0 O 7 . 
 
 Paradatiscetin precipitated from the potassic solution by hydrochloric acid 
 is purified by being first washed with boiling water, next dissolved in strong 
 alcohol, and precipitated by acetate of lead, whereby the unaltered quercetin 
 is removed. The lead from the filtrate is removed by sulphuric acid, and the 
 liquid, after filtration, concentrated by evaporation to one-third its bulk. 
 This sta^e having been reached, the addition of water causes the precipitation 
 of a bulky, white, flocculent mass, which, when re-dissolved in boiling hot but 
 very dilute alcohol, yields, on cooling, shiny yellowish needle-shaped crystals. 
 This substance is an acid, yielding with bases — and especially baryta and 
 strontia — well-crystallised compounds. Paradatiscetin, the acid named, is 
 very sparingly soluble in cold or boiling water, but readily soluble in weak 
 alcohol; less soluble in ether. Its alcoholic solution is coloured an intense 
 deep purple by the addition of perchloride of iron ; acetate of lead does not 
 precipitate the alcoholic solution, but yields with the aqueous solution a yellow 
 precipitate ; weak caustic potassa and soda dissolve paradatiscetin, the liquid 
 at first appearing yellow, but soon turning grass green on contact with air; 
 addition of an aqueous solution of bromine colours the aqueous or alcoholic 
 solution first red, and next brilliant violet ; addition of an alkali to this liquid 
 turns the mixture blue; and if next hydrochloric acid be added, there ensues 
 a red flocculent precipitate, which yields with alcohol a red solution. Chlorine 
 water causes a brown-red colouration, while the solution of paradatiscetin 
 is coloured reddish-brown by solution of bleaching-powder. 
 
 When submitted to heat, paradatiscetin fuses, yielding a reddish-yellow 
 mass. The composition of this substance is — 
 
 C I5 H I0 O6= C I5 H I O 7 -O. 
 
 Quercetic acid. 
 The baryta salt, 2Ci 5 H 10 06,Ba,H202, crystallises in needle-shaped crystals. 
 
USE MADE OF QUERCITRON. 
 
 401 
 
 The formula C i5 Hi Oq is also given by Dr. Stenhouse to datiscetin, a body 
 extracted by him from Datisca cannabina. It appears that the properties of 
 this latter body and of paradatiscetin agree so closely as to allow the conclu- 
 sion that these substances are identical. When the reaction of caustic 
 potassa with quercetin is pushed further, the first-named substance is split up 
 into two new substances, viz., quercimeric and protocatechuic acids ; the former 
 is very soluble in water, alcohol, and ether, crystallises in granular masses, 
 and is coloured a deep blue by perchloride of iron ; its reactions are rather 
 similar to those exhibited by quercetic acid. Its formula is C 9 H60 5 + H 2 0. 
 
 Protocatechuic acid, CyH^O^, is soluble in ether ; it takes a greenish-blue 
 colour with the salts of peroxide of iron : addition of alkaline carbonates turns 
 this colour to a red. Neutral solutions of protoxide of iron (neutralised by 
 means of carbonate of baryta) yield, with protocatechuic acid, a beautiful 
 violet colouration. 
 
 When a sodic solution of quercetin is heated with sodium amalgam until 
 the deep brown first produced has become brownish-yellow, and the mixture 
 is next neutralised with hydrochloric acid, air being excluded, and the liquid 
 shaken up with ether, phloroglucin and two other substances are isolated, 
 one of which, C7H8O3, is very soluble ; the other, insoluble but readily 
 crystallised, is Ci 3 Hi 2 3 . An alcoholic solution of quercetin, acidulated with 
 hydrochloric acid, assumes, when in contact with sodium amalgam, a purple 
 colour, and the liquid yields, on concentration, red crystals analogous to 
 isomorin. This material kept in alcoholic solution reproduces quercetin very 
 readily, especially if an alkali be present. Dr. Stein* first described this sub- 
 stance as paracarthamin : it becomes yellow under the influence of alkalies, 
 but acids restore the red colour ; it differs from carthamin only by containing 
 more water. 
 
 Hlasiwetz and Pfaundler have fully described and illustrated, by a series of 
 formula?, all the reactions and the results thereof relating to quercitrin and its 
 various derivatives, but as yet the precise molecular weight of quercitrin and 
 quercetin are not established. 
 
 Use made of Quercitron. 
 
 Quercitron is met with in trade as a powder, and is also used in that state 
 in dyeing. Relying upon the labours of M. Rigaud, and upon the splitting up 
 of quercitrin into glucose and quercetin, M. Leeshing commenced, in 1855, to 
 boil the quercitron with dilute sulphuric acid : if this operation is succeeded 
 by a thorough washing of the material with cold water, the result is the 
 removal of the tannin and lime-salts from the ware, and the conversion of the 
 soluble quercitrin into sparingly soluble quercetin. Leeshing boils for an hour, 
 by means of a jet of steam, in a leaden tank supported by strong woodwork, 
 80 gallons of water, 100 kilos, of concentrated sulphuric or 200 kilos, of 
 hydrochloric (sp. gr. 1T92), and 200 kilos, of quercitron : after standing the 
 acid liquid is decanted, and the residue thoroughly washed with cold water, 
 first by decantation and next on cloth filters, and the mass (purified quercitron) 
 is finally strongly pressed. 
 
 Another plan is to boil 500 kilos, of quercitron with a solution of 15 kilos. 
 
 * "Zeitschrift fur Chemie und Pharmacie," 1863, p. 467. "Journal fur Prakt. Chemie," 
 vol. lxxxv., p. 351, and vol. lxxxix., p. 491. 
 
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 402 
 
 DYEING AND CALICO PRINTING. 
 
 of crystals of soda (carbonate), in 4000 kilos, of water, for a quarter of an 
 hour, and next 61 kilos, of concentrated sulphuric acid are added, and the 
 mixture boiled for three-quarters of an hour, and afterwards washed and 
 pressed. 
 
 M. G. Schseffer boils 100 parts of pulverised quercitron with 280 parts of 
 water and 25 parts of concentrated sulphuric acid. 
 
 M. Schlumberger prefers 100 parts of quercitron, 300 of water, and 15 of 
 acid: 100 parts of quercitron yield 85 parts of what is termed "commercial 
 quercetin," which has as much tinctorial value as 250 parts of quercitron.* 
 
 This material (viz., the commercial quercetin) possesses the following advan- 
 tages over the quercitron: — (1). The removal of the tannin contained in the 
 quercitron, whereby the injurious action of that tannin upon the brightness of 
 the colour is prevented. (2). An absolute gain as to colouring matter is 
 obtained. (3). The shades produced on the textile fabrics are more full-bodied 
 and livelier. On the other hand, dyeing with this preparation requires a 
 higher temperature (ioo c ) than quercitron ; the portions intended to be kept 
 white are more soiled ; the shades produced are more fugitive ; and, lastly, 
 owing to the insolubility, or at least sparing solubility, of the quercetin, no 
 decoctions of the commercial quercetin can be made. M. Schlumberger has 
 found, however, that boiling with dilute sulphuric acid, applied to other yellow 
 colouring matters, — as, for instance, sumach, weld, Persian berries, fustic, 
 turmeric, — yields excellent results, as far as the brightness of the colours pro- 
 duced and the productivity of the ware are concerned ; so that, just as in case 
 of quercitron, there are obtained, by the above treatment, preparations of 
 absolutely increased tinctorial value. 
 
 The most important commercial preparation of quercitron is flavin, a dye- 
 ware about which there is no little mystery, — due, perhaps, to the fad that the 
 name has been given to a variety of bodies obtained by totally different pro- 
 cesses. English made flavin is obtained by dissolving out the colour of quercitron 
 in weak alkaline solutions, and precipitating by the addition of sulphuric or 
 hydrochloric acid. It is sometimes adulterated with common salt to the 
 extent of 8 per cent. There are again flavins so-called, imported from 
 America, which appear to be merely bark, mechanically purified by a process 
 of thrashing and sifting. The superior American flavin is said to be made 
 by cutting up the perfectly fresh bark, freed from its epidermis, and extracting 
 it with steam at a temperature of 102 to 103 C. The condensed water con- 
 tains the flavin partly in solution and partly in suspension. Several patents 
 for the manufa<tnre of flavin have been taken out in the United States. 
 Some flavins, on chemical examination," prove to be nearly pure quercitrin, 
 and others nearly pure quercetin, a fact; which proves want of uniformity in 
 the mode of preparation. Good flavin has about sixteen times the tinctorial 
 value of quercitron bark. 
 
 For the purposes of calico-printing either the freshly-prepared decoctions of 
 quercitron are used, or liquid extracts of a specific gravity varying from 1*070 
 to i" 152, and known as bark liquor, or the substance known as flavin, and 
 imported from America in the form of an olive-yellow powder. 
 
 Quercitron and its commercial derivatives yield, to mordanted calico, the 
 undermentioned shades : — With aluminous mordants, canary-yellow ; with 
 
 * " Bulletin de la Societe Induatrielle de Mulhouse," vol. xxvii., p. 411. 
 
PERSIAN BERRIES. 
 
 403 
 
 iron mordants, grey, olive-green, and a peculiar kind of black, according to 
 the strength of the mordant applied ; with oxide of chromium, an olive-yellow; 
 with a mixture of alumina and iron, reseda-colour is produced (the colour 
 exhibited by the flower known as Reseda or mignonette) ; with tin mordants a 
 yellow is obtained. 
 
 Persian berries — often simply known as " berries," or with a series of addi- 
 tional aliases, chiefly indicating the country whence they are imported — are 
 the seed-bearing fruit of different species of shrubs known as Rhamnus, and 
 growing wild or cultivated in Southern France, in Spain, Italy, Turkey, 
 Roumania (the Moldo-Wallachian States), the Levant, and Persia. The berry 
 has the size of a pea, but bears three or four semicircular depressions, cor- 
 responding to the number of the flattened seeds it contains. The colour of 
 the dried ware, as met with in commerce, varies from yellowish-green to black, 
 but berries of the latter colour are too old to yield any good results in dyeing. 
 The taste of the berries is bitter, and they give off a very nauseous and sick- 
 ening smell. The following kinds are met with in the trade : — 
 
 1. The Persian berry properly so-called is larger than the other kinds, and 
 
 produced by the Rhamnus amygdalinus, oleo'ides, and saxatilis. It is 
 imported from Smyrna and Aleppo: the colour is beautifully green; 
 shape elongated; size that of a large pea, four seeds triangular-shaped ; 
 taste bitter; very rich in colouring matter; sorted, according to size, 
 in three varieties — large, middling, and small. 
 
 2. Levant berries, grown in Natolia and other parts of Turkey ; brought to 
 
 Europe by way of Constantinople and Smyrna. Their size is that of a 
 peppercorn ; they contain three seeds. Among the best kinds of the so- 
 called Levant berries are those grown in Roumania and Bessarabia. 
 
 3. Morea berries. A large-sized berry, containing two seeds; colour a 
 
 light yellow. 
 
 4. Avignon or French berries ; the produce of the Rhamnus infectorius and 
 
 alaternus. Colour deep green ; size of a peppercorn ; shape flattened, 
 contains two seeds ; quality less good than the Persian. 
 
 5. Spanish berries ; the produce of the Rhamnus saxatilis. In shape and 
 
 size like to the previous-named kind ; colour rather more yellow, and 
 considered of better quality. 
 
 6. Italian berries ; the product also of the Rhamnus infectorius, and very 
 
 similar to the Avignon berries. 
 
 7. Hungarian berries; the product of the Rhamnus catharlicus and saxatilis. 
 
 The size of peas; are considered of good quality. 
 The decoction of these berries has a yellow-greenish colour, and turns 
 orange on the addition of alkalies or alkaline earth, which latter also cause 
 the formation of a slight flocculent precipitate. The decoction is not precipi- 
 tated by acetate of lead or acetate of copper ; tin-salt turns the colour of the 
 decoction to a greenish-yellow. 
 
 • The colouring matters known as xanthorhamnin, rhamnin, chrysorham- 
 nin, rhamnetin, and rhamnoxanthin, contained in the berries just men- 
 tioned, now require our attention. The berries contain several colouring 
 glucosides soluble in water, and besides, according to Bolley, a yellow colour 
 insoluble in water, which he states to be qucrcetin. The existence of several 
 
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 404 
 
 DYEING AND CALICO PRINTING. 
 
 colouring glucosides in these berries appears proved by the labours of Persoz,* 
 Gellaty,f Ortlieb,+ Schiitzenberger and Berteche.|| 
 
 M. Persoz observes, that when decoctions of the berries are left for a length 
 of time to themselves they enter into alcoholic fermentation, thereby depositing 
 a crystalline matter, sparingly soluble in water. This appears due to a slow 
 saponification of one of the glucosides. M. Ortlieb found that when a decoc- 
 tion of the berries is acidulated with sulphuric acid, and then boiled, the same 
 reaction is effected in a few minutes. M. Gellaty has extracted from the 
 berries, by means of alcohol, a large quantity of a yellow, crystalline, insipid 
 matter, soluble in cold water and alcohol, but not in ether, and capable of 
 being split up, by means of ebullition with dilute sulphuric acid, into glucose 
 and another yellow flocculent body. The first-mentioned body he calls 
 xanthorhamnin, and the derivative rhamnetin, and represents this reaction by 
 the following formulas : — 
 
 C 23 H 28 I4 +3H 2 = CxaH^Oi a+ CnHtoOg . 
 
 Xanthorhamnin. Glucose. Rhamnetin. 
 
 The substance obtained by M. Ortlieb while boiling a decoction of the berries 
 with dilute sulphuric acid, and that investigated by Dr. Schiitzenberger and 
 M. Berteche, are evidently also rhamnetin, which latter, when properly puri- 
 fied by means of dilute alcohol and ether, is a crystalline golden-yellow body, 
 sparingly soluble, even in boiling water (1 litre of boiling water dissolves 
 653 milligrammes). What is dissolved is precipitated on cooling. The sub- 
 stance is easily soluble in alcohol and ether. The last-named chemist found 
 that the results of the elementary analysis of this substance agreed with the 
 formula C I2 Hi 5 . 
 
 When rhamnetin is heated along with caustic potassa it is, like quercetin 
 under the same conditions, split up into a saccharine matter and an acid, the 
 composition of which was not determined. If heated to 140 , in sealed tubes, 
 with anhydrous acetic acid, rhamnetin is converted into several acetic deriva- 
 tives, insoluble in water, of a pale yellow colour, and among which one is 
 found capable of separating from an alcoholic solution in white crystals. 
 Rhamnetin may therefore be viewed as a polyatomic alcohol ; and it would 
 appear probable that, if the formula of quercetin is taken at CnHsOj, it is a 
 lower homologue of rhamnetin, but even if the identity of the two bodies 
 just named were positively settled, which is not the case, there is no possi- 
 bility of confusing quercitrin and xanthorhamnin, the latter being far more 
 soluble in water than the former. 
 
 judging by its properties and composition, the substance extracted by 
 Dr. Kane from yellow berries, by means of ether, and named by him chryso- 
 rhamnin, appears to be rhamnetin, and the same remark applies to the body 
 which M. Fleury named rhamnin, and which he obtained from the young twigs 
 of the Rhamnus shrub. § The rhamnoxanthin, which BuchnerU obtained from 
 the bark and berries of a shrub related to the Rhamnus species, appears to 
 differ from rhamnetin by being volatile. 
 
 * " Traite de l'Impression des Tissus," vol. i. 
 
 + " Edinb. New Phil. Journal," vol. vii., p. 2 52. 
 
 t " Bulletins de la Societo Industrielle de Mulhouse," vol. xxx., p. 16. 
 
 II Ibid., vol. xxxv., p. 455. 
 
 § " Journ. de Pharm.," vol. xxvii., p. 666. 
 
 51 Ibid., 3rd series, vol. xxiv., p. 50. 
 
FUSTIC. 
 
 405 
 
 The colouring matter contained in the berries produces, upon mordanted 
 cloth, colours analogous to those mentioned under quercitron ; the yellow is 
 brighter and more intense, but also more fugitive. In dyeing, as well as in 
 printing, the berries — either whole or previously bruised — are employed, or de- 
 coctions more or less concentrated. When the berries are exhausted with 
 boiling water, the first decoctions are of better quality, and yield purer colours 
 than the second and third : the decoctions should be used when freshly made, 
 because they spoil and turn " greasy" as it is termed. The berries are also 
 applied in woollen dyeing, and for the colour -nown as stil de grain— a. kind of 
 yellow lake — used as paint, especially for in-door work and theatrical decora- 
 tions, and prepared by precipitating with milk of chalk a decoction of the 
 berries mixed with alum, either alone or with the addition of quercitron and 
 fustic, and by gently drying the precipitate thus produced. The chief use of 
 the berry-liquor is for steam- and so-called application-colours. The decoction 
 is often made with water and vinegar, as producing a liquor which keeps better. 
 The chief use of this yellow pigment is in greens. 
 
 Fustic, Yellow Brazil Wood, Cuba Wood, Yellow W T ood, Old Fustic. 
 
 Under the above names there is imported, from different tropical regions, the 
 decorticated wood of a tree botanically known as Moms tinctoria, belonging 
 to the natural order of the Urticaceae, and growing wild in some portions of 
 India, the hotter part of South America, Mexico, Jamaica, Cuba, Tobago, 
 often attaining a height of 20 metres. The wood is found in large pieces, 
 sawn straight at both ends, but otherwise rather of irregular shape, and 
 deprived of its bark. The wood is hard, but brittle and light ; its colour is a 
 pale lemon-yellow. 
 
 The trade distinguishes several varieties, according to the locality of ex- 
 portation, which is not always identical with the locality of growth. Among 
 these varieties we notice — Cuba wood, considered the best ; Tampico, gene- 
 rally a little brighter-coloured than the preceding ; yellow Brazil wood, colour 
 very bright, and usually more or less attacked by worms ; further, Porto Rico, 
 Carthagena, Macaraibo, St. Domingo, Jamaica, Tuspan, and India woods. 
 The higher qualities are the hardest and also the least worm-eaten, of a light 
 yellow colour, with reddish veins. This wood is often sold ground-up or 
 reduced to shavings. 
 
 The decoctions have the following behaviour with different reagents : — 
 Alkalies and alkaline earths, deep orange-yellow colouration, without any 
 precipitate : sulphuric, nitric, and oxalic acids produce a slight precipitate ; 
 alum, a yellow precipitate ; sulphate of peroxide of iron, first an olive 
 colouration, next a deep olive-black precipitate ;* chloride of tin, acetate of 
 lead, and acetate of copper produce a yellow or brownish-yellow precipitate ; 
 gelatin gives a yellow flocculent precipitate. 
 
 The colouring matters contained in this wood have been investigated by 
 Chevreul.t Wagner,* and, more recently, by Hlasiwetz and Pfaundler. || These 
 
 * The idea of olive-black may perhaps seem preposterous to those of our readers who never 
 saw that fruit fully ripe, but in that state its colour is indeed deep greenish-black, with a 
 bronze reflection. 
 
 + " Lecons de Chimie Appliquee a la Teinture," vol. ii., p. 150. 
 
 } " Journal fiir Prakt. Chem.," vol. Ii., p. 82. 
 
 II " Annalcn der Chemie und Pharmacie,'' vol. exxvii., p. 351, and " Comptes Rendus de 
 1' Academic des Sciences de V'icnnc," June, 1SO4. 
 
19 W^WWMNPPPPPPPPPPlP'WlHHfflliBMllli 
 
 HGBBEEHUSB 
 
 406 
 
 DYEING AND CALICO PRINTING. 
 
 authors agree generally in this, that the wood contains two entirely distind 
 principles, one of which is nearly insoluble in water, while the other is rather 
 readily soluble therein. The former is named morin, and the latter morin- 
 tannic acid, or maclurin. Hlasiwetz and Pfaundler thus describe the opera- 
 tions required for the separation of these substances from each other and from 
 the other matters contained in the wood : — The wood, previously rasped, is 
 two or three times exhausted with boiling water, and the mixed liquors are — 
 after having been concentrated by evaporation — left to stand for several days. 
 A crystalline matter is slowly deposited, which has to be rapidly washed by 
 decantation with cold water, and is next placed in a cloth and strongly 
 pressed. This substance, which contains the principles just named, is fre- 
 quently thrown down from the strong decoctions of the wood (sp. gr. 1*070), 
 as prepared for use in dye-houses, and that deposit may serve, with great ad- 
 vantage, for the preparations to be mentioned. The strongly-pressed dry 
 mass is first pulverised, and next repeatedly treated with boiling water ; the 
 remaining insoluble residue, crude morin, mixed with a small quantity of that 
 substance combined with lime, is therefore first acted upon by dilute hydro- 
 chloric acid, well washed, and next dissolved in alcohol, from which latter — 
 after the addition of two-thirds of its bulk of hot water — the morin separates 
 in the form of yellow acicular crystals, which are further purified by repeated 
 crystallisation from dilute alcohol. The morintannic acid is left in the water 
 employed for the exhaustion of the original deposit from this solution. It is 
 separated partly by the concentration of the solution by evaporation, and 
 partly by the addition of hydrochloric acid ; it is purified by means of 
 repeated crystallisations from an acidulated aqueous solution. This sub- 
 stance is the chief constituent of the crystalline deposits seen by M. Chevreui 
 in the blocks of the fustic. 
 
 Morintannic Acid. — The crystals of this body, as obtained by the mode of 
 preparation just described, are yellow, but may be obtained entirely colourless 
 by adding to the aqueous solution acetic acid and acetate of lead, and next 
 passing a current of sulphuretted hydrogen through the liquid ; the sulphide 
 of lead, while falling down, carries along with it the small quantity of yellow 
 colouring matter which contaminates the crystals. 
 
 This acid is very soluble in hot water, 1 part of the acid requiring 2*14 parts 
 of hot and 6 - 4 parts of cold water for its solution ; it is also soluble in alcohol, 
 wood-spirit, and ether, fuses at 200 , and is decomposed at 250 . Sulphate of 
 iron yields with it a greenish-black, and acetate of lead a yellow, precipitate ; 
 the latter soluble in acetic acid. It docs net completely lose its water below 
 140 . Its composition is C I3 Hi 06. By the action of concentrated and warm 
 solutions of caustic alkalies it is split up into phloroglucin and protocatechuic 
 acid. A moderately concentrated solution, boiled with zinc and dilute sul- 
 phuric acid, rapidly becomes intensely red : this colouration gradually, 
 however, fades away, leaving a wine-yellow colour (colour of Lunel or 
 Frontignac so-called white wine). By this operation phloroglucin and a new 
 product, machromin, are formed. The last-named substance is isolated in the 
 following manner : — To the liquid decanted from the excess of zinc is first 
 added the third part of its bulk of alcohol, and it is next shaken up with ether 
 as long as that liquid becomes coloured ; the ethereal solution is evaporated, 
 the residue diluted with water, and precipitated with acetate of lead ; the 
 
MORINTANNIC ACID. 
 
 407 
 
 ensuing precipitate is at first yellow, but gradually turns green. The filtrate 
 contains the phloroglucin ; the lead compound is suspended in boiling water, 
 and decomposed with sulphuretted hydrogen ; after filtration the liquid is 
 evaporated in vacuo over sulphuric acid. During the evaporation the liquid, 
 which deposits small crystals, becomes coloured ; the crystals are first washed 
 with cold water, and next dissolved in boiling dilute alcohol, from which, on 
 cooling, they are deposited in brilliantly shining needles. 
 
 The most interesting property of machromin is its great facility of turning 
 blue in solution, as well as in the solid state, on contact with air or under the 
 influence of oxidising substances. The solutions of this substance yield, with 
 hydrochloric acid, an indigo-blue precipitate ; with perchloride of iron and 
 bichloride of mercury this body developes a beautiful violet colouration, which 
 turns gradually blue ; the alkaline and ammoniacal solutions also become blue 
 on contact with air. Machromin in solution reduces nitrate of silver to the 
 metallic state, while the liquid assumes simultaneously a violet colour. Con- 
 centrated sulphuric acid dissolves machromin, yielding a liquid at first orange, 
 next yellow, but which on heating turns deep green, which hue remains after 
 dilution of the acid with water. This green liquid is turned violet by alkalies. 
 The formula of this body is C I4 H I0 5 -|-3H20 ; the blue material formed by 
 the oxidation of the machromin is most readily obtained by adding to an 
 aqueous solution of that body an excess of perchloride of iron. The blue 
 matter precipitates in the shape of a flocculent mass, is collected on a filter, 
 washed with water, dried and pulverised, and exhausted with ether, when it 
 appears as an amorphous dark blue mass, soluble in alcohol, the solution 
 having also a blue colour. This alcoholic solution, acidulated with sulphuric 
 acid, is decolourised by the addition of zinc and sodium amalgam. The 
 composition of this blue substance appears to be C I4 H80 3 , or machromin 
 less H 2 . 
 
 Dr. Hlasiwetz has directly prepared machromin from protocatechuic acid by 
 reduction. When machromin in alkaline solution is treated with sodium 
 amalgam the liquid becomes first deep brown, then red, turning finally yellow. 
 After saturating this alkaline solution with hydrochloric acid, and shaking up 
 with ether, the new result of the decomposition may be separated by evaporating 
 the ethereal solution, taking up the residue with water, and precipitating it 
 with acetate of lead. The precipitate, after having been well washed, and 
 being decomposed with sulphuretted hydrogen, yields, on evaporation of the 
 aqueous filtered liquid, an amorphous body, soluble in water, alcohol, and 
 ether, and composed of C14H12O5. 
 
 A solution of moritannic acid in sulphuric acid deposits, after having been 
 allowed to stand for some time, a new acid called rufimoric, in the shape of a 
 brick-red crystalline precipitate, soluble in ammonia, with a purplish colour. 
 On being boiled with caustic potassa, rufimoric acid is re-converted intomorin- 
 tannic acid. Moritannic, or morintannic acid, is by some termed Maclurin. 
 The plan of naming chemical compounds after their discoverers, or after 
 other chemists, even if eminent, is highly objectionable, -and if tolerated 
 would become a greater nuisance than the sesquipedalian nomenclature of 
 certain modern authorities. 
 
 Morin is nearly insoluble in cold, and very slightly soluble in boiling, water; 
 soluble in alcohol, very slightly soluble in ether, insoluble in sulphide of 
 
SSSS T*PCfKTPFi>L»LBLl 
 
 408 DYEING AND CALICO PRINTING. 
 
 carbon. Alkalies, and soluble alkaline borates and phosphates, dissolve 
 morin, giving yellow solutions, which are precipitated by acids. The alco- 
 holic solution is coloured a deep olive-green by perchloride of iron. Morin 
 loses its water of crystallisation with great difficulty. 
 
 According to Dr. Hlasiwetz the composition of morin, dried at 200 , is 
 Ci 2 Hs0 5 , while the air-dried substance is represented by C I2 Hs0 5 ijH 2 0. 
 Morin readily combines with potassa, soda, lime, baryta, oxides of zinc 
 and lead, all these compounds being yellow. It absorbs ammonia, even 
 so as to increase its weight by 127 per cent, causing the formation of a 
 body Ci2H 10 06 + 2NH 3 — H 2 0. It also combines with bromine, and is readily 
 converted into phloroglucin under the influence of nascent hydrogen or by 
 fusion with alkalies. 
 
 It appears from the investigations made by Hlasiwetz that there exists great 
 analogy between morin and quercetin, as .may be inferred from the following 
 brief quotations from the lengthy memoir of the author on this subject : — 
 Both these substances yield, when treated with sodium amalgam while in an 
 acidulated alcoholic solution, a red body ; treated with the same amalgam in 
 an alkaline solution, phloroglucin is formed ; both unite with potassa and 
 soda, as well as with zinc ; both are converted by fusing caustic potassa into 
 phloroglucin, and both withstand a high temperature and lose their water of 
 crystallisation with difficulty. 
 
 Fustic is employed for the preparation of decodions and more or less con- 
 centrated extracts which are used in dyeing, while it also serves for the 
 manufacture of lakes destined for paints and for calico-printing. The shades 
 of colours produced are nearly the same as those from quercitron, and are 
 equally stable. 
 
 Weld. 
 (French, Gaude ; German, Wciu ; Dutch, Wouw.) 
 
 This substance is the dried herbaceous plant known botanically as Reseda 
 lutcola. It is cultivated on the Continent of Europe, but in this country has 
 fallen into disuse ; it is sown in June, and gathered the next year : the plant, 
 which reaches about 1-3 metres in height, is brown, like grass dried in the 
 shade, and sold in sheaves, like straw. It consists of a main stem and several 
 smaller branches, of a yellow or greenish-yellow colour, according to the care 
 taken in drying. 
 
 Weld is cultivated in several parts of France, in Germany, and the Austro- 
 Hungarian empire. The colouring matter is dispersed through the entire 
 plant, but is most accumulated towards the upper extremity and in the seeds. 
 The decottions of this material have a greenish-yellow colour, a sweetish- 
 bitter taste, and a very disagreeable odour. Alkalies turn this decoction a 
 golden-yellow ; acids deepen the yellow hue ; with sulphate of iron an olive- 
 green is produced, while most of the metallic salts give yellow precipitates. 
 Gelatin causes only an insignificant precipitate in the decoction. 
 
 Though the use of weld in this country has almost entirely ceased, mainly 
 owing to the fact that farmers do not cultivate it here as they used to do, and 
 on account also of the bulk of the material, we must not omit to enter into 
 some details of the chemical history of this dye-ware, which is the oldest 
 European yellow dye known, and was used even by the Gauls and other 
 nations dwelling north of the Alps in the time of Julius Ca:sar. The 
 
WELD. 
 
 409 
 
 colouring matter contained in this plant has been studied by MM. Chevreul,* 
 Moldenhauer,f and Schiitzenberger and Paraf.J The mode of extracting the 
 colouring matter from this plant employed by the two last-named authors, is 
 based upon the fact that luteolin is readily soluble in water, heated under 
 pressure to 250 (equal to a pressure of about 40 atmospheres or 41*32 kilos. 
 to the square centimetre), and crystallises, on cooling, in the shape of yellow 
 needles, which are perfectly pure, and free from a peculiar, easily fusible, 
 resinous matter, which accompanies the luteolin in large quantity. The raw 
 weld is first cut up in small fragments, and exhausted in a displacement 
 apparatus with boiling alcohol. The solution thus obtained is first concen- 
 trated by evaporation, and next precipitated by water, which throws down 
 an abundant dirty green yellowish flocculent substance. This matter is put 
 along with water into a glass cylinder, which is placed inside a cast-steel or 
 a stout sheet copper cylinder, closed with a screw cap, and heated to 250 for 
 about twenty minutes. On cooling, the slides of the glass cylinder are, for 
 the space occupied by the water, found lined with brilliant golden needle- 
 shaped crystals, while at the bottom of the glass the resin is accumulated 
 fused to a cake. The mother-liquor, in the midst of which this crystallisation 
 took place, is perfectly clear and transparent. The crystals are purified by 
 another operation of the same kind as just described, and the resin is separately 
 submitted for two or three times to the same treatment, whereby it is entirely 
 freed from colouring matter. 
 
 The process employed by M. Moldenhauer is the following : — The dried plant 
 is exhausted with alcohol, and the tincture obtained is evaporated, whereby a 
 portion of the luteolin is deposited ; this substance is washed with water, 
 and next boiled with concentrated acetic acid. Being filtered while hot this 
 acid solution deposits the luteolin on cooling ; the deposit is first washed 
 with water, next dried in vacuo over sulphuric acid, then treated with ether, 
 and re-dissolved in alcohol ; to this solution from 24 to 28 parts of water are 
 added, and the fluid boiled, whereby the luteolin separates in the pure 
 crystalline state. Luteolin thus obtained is a yellow needle-shaped crystalline 
 substance ; its taste is bitter and astringent ; it is free from smell, fuses at 
 about 320°, and sublimes, undergoing a partial decomposition ; it is sparingly 
 soluble in cold, and not freely so in hot, water, but readily in alcohol and 
 ether. Luteolin dissolves in caustic and carbonated alkaline lyes, yielding 
 deep yellow solutions. In concentrated sulphuric acid it dissolves, yielding 
 an orange-red liquid, from which water re-precipitates the luteolin unal- 
 tered. Luteolin is also soluble in boiling acetic and hydrochloric acids, 
 but not in these fluids when cold ; treated when dry with anhydrous phos- 
 phoric acid luteolin is converted into a red body, soluble in ammonia, with a 
 violet colour; nitric acid converts luteolin into oxalic acid. The aqueous 
 solutions of this dye are coloured green by perchloride of iron, and are pre- 
 cipitated by nearly all metallic saline solutions. The formula of luteolin, 
 dried at 150 , is C I2 H80 5 , and the formula of the pigment, dried over sul- 
 phuric acid in vacuo, is C I2 H80 5 H 2 05; luteolin is not a glucoside. Weld or 
 wold only yields colours upon previously mordanted fabrics. The shades 
 
 * "Journal de Chimie Medicale," vi., 157. 
 
 t " Journal fur Praktische Chemie,"lxx., 428. " Ann. der Chem. und Pharmacie," cxii., 107. 
 
 J " Bulletin de la Societe Chimique de Paris,'" first series, 1861, p. 18. 
 

 ■bb 
 
 410 
 
 DYEING AND CALICO PRINTING. 
 
 produced are similar to those of quercitron, but so fast as to be comparable 
 to those of madder. 
 
 Before we enter into more details on the application of the yellow dye-stuffs 
 treated of, we have to pay some attention to certain colouring matters re- 
 sembling quercitron, and considered by some authors identical therewith, 
 while others deny such identity ; these matters are the following : — 
 
 Rutin, also called rutic or rutinic acid, melin, phytomelin. According to 
 Hlasiwetz, this substance, obtained by MM. Weiss, Kummel, and Borntraeger 
 from the leaves of the Rata graveolcns, does not at all differ from quercitrin, 
 while Dr. Schunck and M. Stein* declare this opinion incorrect, and pronounce 
 this body entirely distinct from quercitrin by its composition and properties. 
 Melin is less coloured than quercitrin, and the percentical composition of 
 these bodies differs considerably; melin containing in 100 parts — Carbon, 
 50-06 ; hydrogen, 5-65; but quercitrin — Carbon, 54*85; hydrogen, 5 - i5. 
 Melin is also more soluble in water, hot as well as cold, as also in alcohol. 
 The alcoholic solution of melin is precipitated by acetate of lead with a 
 golden-yellow, but that of quercitrin with an orange-red. Melin is most 
 readily obtained from the so-called Chinese yellow berries, the leaf buds of 
 the Sophora japonica, which are exhausted with alcohol at 80 per cent ; a 
 small quantity of hydrated oxide of lead is first added to the solution, in 
 order to eliminate impurities ; the ensuing precipitate is filtered off, and to 
 the filtrate is next added a larger quantity of the same oxide, and the ensuing 
 yellow precipitate, after having been collected on a filter and washed, is 
 suspended in alcohol and decomposed by sulphuretted hydrogen. The sul- 
 phide of lead having been filtered off, the solution yields, on evaporation, a 
 golden-yellow crystalline substance, which is melin, and which by being 
 boiled with dilute mineral acids is split up into glucose, and a new yellow body, 
 melletin, somewhat like quercetin. The formula of melin is, according to 
 M. Stein, C^r^O^, while Zwenger and Drouke maintain that the formula 
 of melin, a substance quite distinct from rutin, which latter they extracted 
 from capers (Capparis spinosa) and Ruta graveolcns, as well as from horse- 
 chestnuts, is C2 5 H 32 I7 . 
 
 Robinin has been extracted by the last-named chemists from the fresh 
 flowers of the acacia tree, Robinia pseudoacacia. The flowers are exhausted 
 with water, and the solution evaporated to the consistency of a syrup, then 
 treated with alcohol ; and the extract when evaporated to a small bulk 
 deposits yellow crystals, which are washed with cold alcohol and dissolved in 
 hot water. The solution is partially precipitated by acetate of lead, and the 
 ensuing precipitate having been filtered off the slight excess of lead is re- 
 moved by sulphuretted hydrogen from the yet hot solution, which, on cooling, 
 deposits yellow crystals of robinin. It is a neutral, insipid substance, very 
 sparingly soluble in cold water and alcohol, but more freely in these fluids 
 when hot ; and insoluble in ether. It fuses at 195 to an amorphous mass, 
 which in contact with water combines therewith, and crystallises. Robinin 
 is soluble in alkaline solutions with a yellow colour; nitric acid converts it 
 into oxalic and picric acids. If boiled with dilute sulphuric and hydrochloric 
 acids it is split up into an amorphous and unfermentable glucose, and into 
 quercetin. The glucose yields, on treatment with nitric acid, oxalic and picric 
 
 * "Journal fur Praktische Chcmie," lxxxv., 351 ; and lxxxviii., 280. 
 
RHA MNOXANTHIN. 
 
 411 
 
 acids. Robinin is distinguished from quercitrin by its greater solubility in 
 boiling water, and by the colour it yields with acetate of lead ; its formula is, 
 according to Zwenger and Drouke, C 25 H 30 O I 6. 
 
 Rhamnoxanthin. — Buchner* gives this name to a substance extracted by 
 him from the bark of the Rhamnus cathartica, and by Phipson, from the bark 
 and leaf buds of the Rhamnus frangula. It is a yellow crystalline substance, 
 sparingly soluble in water, but dissolved by alcohol, ether, and alkaline 
 solutions, with a purplish colour. It is volatile, even at common tem- 
 peratures, subliming readily as a yellow crystalline body. When crude 
 rhamnoxanthin is mixed with pure quartz sand and placed in a flask, and the 
 mixture very gently but continuously heated, a body is sublimed which has 
 all the appearance of alizarin, and yields with alkalies cherry-red solutions. 
 
 Colouring Matter of Thuya occidentalis. — Kawalierf has extraded from 
 the leaves of this well-known coniferous tree a yellow body, thuyin, which, 
 on being boiled with dilute sulphuric acid, is split up into an amorphous sugar 
 and thuyetin: — 
 
 C 2 oH 22 I2 + 2H 2 = C 6 H I2 6 -l-C I4 H I4 08 
 
 Thuyin. Sugar. Thuyetin. 
 
 It is probable that the two last-named bodies are identical with quercitrin and 
 quercetin, which they greatly resemble both in their properties and composition. 
 Fustet, Young Fustic, or Zante Fustic is the decorticated wood of a 
 shrub belonging to the natural order of the Terebinthaceae, and botanically 
 known as Rhus cotinus, a native of southern Europe, as well as of some of 
 the West Indian Islands. Fustet is a hard, compad, beautifully yellow wood, 
 imported in bundles and small fagots. The American fustet is more valued 
 than the Italian growth. The wood contains — (1) a crystalline yellow 
 colouring matter; (2) a red substance; (3) a brown astringent principle. The 
 yellow colouring matter was first isolated by M. Chevreul, who named it 
 fustin. Dr. Bolley has more recently investigated this substance, which he 
 considers as identical with quercetin, and prepares as follows:]: — The aqueous 
 decodion of the wood is evaporated to dryness ; the residue treated with 
 alcohol, the insoluble matter retains the red pigment; the alcoholic solution 
 is concentrated by evaporation and mixed with water, whereby the yellow 
 principle is precipitated as a crystalline crust, which after washing with cold 
 water is re-dissolved in alcohol and re-precipitated with water, thus yielding 
 the pure material. Although fustin thus prepared in many respeds resembles 
 quercetin it differs from the latter in some respeds, yielding, for instance, an 
 orange, and not, like quercetin, a yellow precipitate with protochloride of tin ; 
 the alkaline solutions of fustin are red. Dr. Bolley feels inclined to ascribe 
 these differences to a small quantity of the red colouring compounds. Still 
 the identity of quercetin and fustin is not at all proved, and requires further 
 investigation. The fustet red has never been examined, and is probably due 
 to an alteration of the yellow principle. The decodion of fustet exhibits the 
 following readions : — Its colour is orange -yellow ; alkalies turn it red ; 
 
 ♦"Journal de Pharmacie " [3], xxiv., 50; and Dinglei's " Polytechn. Journal," 1865, 
 clxxxviii., p. 143. 
 
 1 Kawalier, " Comptes Kendus de l'Academie de Vicnne, xxix., 10. 
 
 { "Bulletin de la Societe Chimique de Paris," ii., 479. SchweiUcrische, " Polytechnischc 
 Zcitschrift," ix., zz. 
 
niwrm 
 
 412 
 
 DYEING AND CALICO PRINTING. 
 
 alkaline earths redden it, and cause a precipitate ; tin crystals and acetate of 
 lead yield orange precipitates; acetate of copper a chestnut red-brown pre- 
 cipitate; acids turn the colour a greenish yellow. Fustet is chiefly used for 
 dyeing wool and some kinds of skins, and is also, though rarely, used as a 
 tanning material. With aluminous mordants it yields an orange-yellow colour, 
 and with tin mordants an orange-red. These colours are, however, fugitive, 
 and are altered by the action of alkalies and soap ; fustet is not applied in 
 calico printing, and very little in cotton dyeing. 
 
 Colouring Matter from Buckwheat (Polygonum Fagopyrum).* 
 
 Dr. Schunck has extracted from the leaves of this plant a yellow crystalline 
 colouring matter, sparingly soluble in cold, more readily so in hot, water; 
 readily soluble in alcohol, concentrated sulphuric and hydrochloric acids, and in 
 alkalies. According to the author, the formula of this substance is Ci5H 20 O I0 , 
 and he considers it identical with rutin, and also with the ilixanthin (obtained 
 from the leaves of the holly, Ilex aqitifolium). The aqueous solutions of this 
 substance yield, on the addition of acetate of alumina and acetate of lead, 
 yellow precipitates ; with acetate of copper a greenish yellow; and with per- 
 chloride of iron an olive-brown precipitate ; this dye yields, on previously 
 mordanted cotton, bright yellow shades. The pure dye is obtained by making 
 a decoction of the leaves, to which while boiling a small proportion of a 
 solution of acetate of lead is added, in order to precipitate thereby some other 
 vegetable principles; the liquid is filtered while still boiling; hot acetic acid 
 is next added, whereupon the pure material is deposited in the shape of small 
 acicular crystals. t The bark and root of the pomegranate contain beside 
 tannin a yellow colouring matter, which has not been hitherto scientifically 
 investigated, but which, judging from its behaviour in dyeing, approaches to 
 quercitrin and quercetin. It is used by dyers to a small extent for certain 
 shades of drab and grey. The husk or rind of the pomegranate fruit is rarely 
 used in this country as a source of tannin, though it contains upwards of 
 30 per cent of tannic acid, and it yields with iron mordants rich, bloomy blacks, 
 and is used in Spain in preference to sumach both for dyeing and tanning. As 
 regards the use made in dyeing and printing of the yellow colouring matters 
 belonging to the quercetric group, it is evident that the great analogy in 
 properties, composition, and chemical behaviour of these principles must 
 extend to their application as dye materials, but although this is actually so, 
 it is not in practice indifferent whether the one or the other be used, and this 
 i<? chiefly due to the fact that the practical dyer does not employ the pure 
 tinctorial principles, but either the vegetable matter in its native state or 
 aqueous extracts, which are complex substances containing impurities, which 
 in various ways affect the applicability of the dyeing process. 
 
 The following is the general outline of the use of these colours : — None of 
 them can be fixed without the aid of a mordant whatever may be the nature 
 of the fibre. With aluminous or tin mordants the tissues are dyed yellow, 
 orange-yellow, or nankin-yellow, according to the strength of the mordant. 
 With iron the shades obtained vary from grey to olive-green or black. With 
 mixed iron and alumina mordants olive and reseda-yellow colours are 
 
 * " Dingler's " Polytechn. Journal," cxv. , 157. 
 
 t " Repertoire de Chimic Pure," i., p. 438. " Chemical Gazette," Nos. 399 and 201. 
 
DYEING WITH WELD. 
 
 4*3 
 
 produced. With chromium mordants an olive-yellow is produced. These shades 
 are the same upon cotton, silk, and wool, but vary slightly within narrow 
 limits. In dyeing there are employed — (r) the raw vegetable material as it 
 occurs in commerce, generally in the state of a more or less finely pulverised 
 substance; (2) the same material after having been previously treated with 
 dilute and boiling sulphuric acid, the product of this action yields richer and 
 brighter colours, but requires in dyeing a higher temperature, and as a con- 
 sequence thereof the portions of the fabric intended to be left white are more 
 soiled. When the dye material contains tannin in larger quantity, as is the 
 case with quercitron, fustic, and others, it is best to add to the materials of 
 the dye-beck a sufficient quantity of gelatin, in order to neutralise the effects 
 of the tannin. 
 
 Calico is now very generally dyed yellow with quercitron or quercetin, but 
 formerly weld was used, and with the advantage that it yielded faster colours. 
 As regards cotton or calico, previously printed and mordanted, and treated 
 as described for madder, the pieces, four at a time, are placed in a dye-beck, 
 containing per piece, from 750 to 1500 grms. of quercitron, and 60 grms. of 
 glue to each 500 grms. of the last-named substance. The colouring matter 
 dissolves so readily that the goods can be put in the beck immediately after 
 the addition of the dye-ware. The process is commenced at the ordinary 
 temperature of the air; the heat of the contents of the dye-beck is raised in 
 an hour's time to from 38 to about 57 , but for greys the temperature should 
 not exceed 38 . On being taken from the dye-beck the pieces are first 
 thoroughly washed and rinsed in cold water, and next put for a quarter of an 
 hour in a bath of bran, containing 2J kilos, of bran per piece, and at a tem- 
 perature of from 38 to 51 . If the patterns have much white this operation 
 has to be repeated twice, the object being to clear and brighten the grounds. 
 This branning is the only clearing which this dye-ware will bear. 
 
 Dyeing with Weld. — The plant is first boiled in the dye-beck for about 
 half an hour ; it is then removed, and the contents of the beck allowed to cool 
 down to about 63 ; at this heat the goods are entered, four or six pieces at a 
 time. The quantity of weld applied varies from 5 to 10 kilos, per piece, 
 according as the pattern printed on the fabric is more or less heavy; when 
 a white ground is required, and the pattern is light, it is as well to add about 
 60 grms. of glue for each half kilo, of weld. The temperature of the dye- 
 beck is raised in half an hour's time to 75 ; on being removed from the beck 
 the goods are twice branned, the quantity of bran to be 5 kilos, per piece for 
 white ground, and 2i kilos, per piece for yellow ground. After this the pieces 
 are grass bleached for a few days, and next passed through dry bran. The 
 use of weld (although discontinued in this country) has the advantage of 
 leaving the whites purer and more readily cleared than is the case with quer- 
 citron. Pomegranate bark is employed like weld, that is to say, boiled in the 
 beck previous to use. 
 
 Fast cinnamon-yellow or brown shades in the madder style are often first 
 dyed with quercitron and bablah,*or quercitron and pomegranate bark. Where 
 
 * This is the name (also babula or Neb-nab) of a fruit imported from Senegal and India; 
 it was, when first imported, said to have the property of imparting permanency to all dyed 
 colours, but this was found to be an exaggeration. Bablah contains tannic and gallic acids 
 in large quantity, and may be used as a substitute for sumach. 
 
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 414 
 
 DYEING AND CALICO PRINTING. 
 
 a myrtle-green coloured ground is required, the goods are first dyed with quer- 
 citron and pomegranate bark, and next with Brazil wood. It is evident that 
 by varying the nature of the mordant and that of the dye-ware to be super- 
 imposed on the yellow, olive, or grey produced by quercitron or its allies, it is 
 easy to produce a series of various shades and colourations too many to be 
 here enumerated. Among the more important of these mixtures are those by 
 which greens are produced with yellow and blue, about which more will be 
 said when we shall have treated of blue colours. 
 
 We confine our observations here to the following : — When a fabric, pre- 
 viously dyed a vat blue, is mordanted with acetate of alumina, and next dyed 
 with quercitron, weld, or berries, it assumes a green shade ; and when a 
 mixture is made of such materials as will produce steam blue and steam 
 yellow, the result will be the production of a green : this, except the Chinese 
 green, " Lo-kao," and the aniline green, is the only means of producing upon 
 fabrics a green dye of organic origin. 
 
 When cotton yarn has to be dyed yellow it is first sumached, next mor- 
 danted with red liquor (sp. gr. 1*014), squeezed, and immediately placed in a hot 
 quercitron bath, to which tin-salt has been added; the cotton is next washed 
 and dried. For greens the yarn is mordanted with solution of acetate of 
 alumina (sp. gr. 1*034), squeezed, washed with warm water, dyed with quer- 
 citron, aged, mordanted with weak red liquor, well squeezed, and next dyed with 
 extract of indigo. Silk is dyed yellow with quercitron by the following pro- 
 cess: — It is first mordanted with alum (1 part of alum and 10 of water), next 
 dyed in a quercitron bath, to which alum or tin-salt has been added, and the 
 fabric next cleared with soap. If weld or fustic is applied the same process is 
 used for silk ; and if it is desired to produce green it is first dyed yellow, and 
 next indigo carmine is added to the contents of the dye-beck. Wool is first 
 mordanted in a boiling-hot bath, made up of cream of tartar and alum, or of 
 2 kilos, of alum and 20 grms. of sulphuric acid for 10 kilos, of wool ; the 
 specific mordant for wool or yellow spirit consists of 4 kilos, of water, 4 kilos, 
 of sulphuric acid, and 1 kilo, of tin crystals. 
 
 In steam- and application-colours the more or less concentrated decoctions of 
 the yellow dye-ware are frequently used upon cotton, wool, mixed fabrics, and 
 silk ; these decoctions yield when alone, and with suitable mordants, the same 
 shades as when applied in the dye-beck; and in association with other dye 
 materials for either red or blue or other colours, a large and varying series of 
 tints are produced. Decoction of Persian berries is often preferred for this 
 purpose, on account of the greater solubility of its colouring matter, p.nd also 
 because that pigment has not, as is the case with quercitron, a tendency, when 
 in decoction, to separate from the liquid. Extracts of fustic are little used 
 except in mixtures, as for green, because the yellow pigment of this ware is 
 not pure enough for use by itself in the steaming process, and has a tendency 
 to become rust-coloured. 
 
 Upon Cotton. — The fixing basis for yellow matter is alumina, to which 
 are added sometimes tin preparations, and sometimes also preparations of 
 copper, these latter playing a secondary part and acting as oxidisers. 
 
 The following are the chief substances in use for steam-yellows : — Extracts 
 of quercitron, Persian berries, and fustic. The mordants are — Acetate of 
 alumina (weak red liquor, as for madder) ; small quantities of proto- and 
 
ALOES. 
 
 41. 
 
 bi-chloride of tin, but always in small quantity as compared with the alumina, 
 since it is employed more as an alterant than as a mordant ; thickeners ; 
 various other materials, e.g., acetic acid, are added, though not absolutely 
 necessary. The goods are previously prepared with alumina or stannate 
 of soda. 
 
 Application-Yellows are generally prepared with berries and tin-salts, while 
 alumina is the mordant. 
 
 Steam Reseda-Yellow : made up with quercitron extract, pyrolignite of iron, 
 and an aluminous mordant. 
 
 Steam-Grey is chiefly made up of quercitron extract, extract of Brazil wood, 
 decoction of nutgalls, sulphate of iron, pyroligneous acid, and bichromate of 
 potassa ; or extracts of Brazil wood and quercitron, with pyrolignite of iron, 
 acetate of iron, and berry liquor; or acetate of iron, alum, berry liquor, 
 decoction of nut-galls. 
 
 Steam-Olive is made up of berry liquor, acetate of iron, and tin-salt. 
 
 Steam-Brown (Puce) is mainly made up of mixed extracts of Lima and 
 St. Martha woods, quercitron, pyrolignite of alumina, chlorate of potassa ; 
 also of berry liquor, fustic, and Lima wood decoctions, red liquor, acetate of 
 copper, sal-ammoniac — this latter material acting, during the printing process, 
 in a physical manner, and during the oxidation chemically, somewhat as in 
 aniline-black. 
 
 Application-Puce is made up of berry liquor, Lima wood extract, bichloride 
 and protochloride of tin, and nitrate of iron. 
 
 Steam-Orange is made up of berry liquor and extract of St. Martha wood, an 
 aluminous mordant, and acetate of copper. 
 
 Application-Orange is chiefly made up of berries, St. Martha wood, and bi- 
 chloride of tin. 
 
 Steam-Greens are prepared by a mixture of steam-blue with berry liquor, red 
 liquor (as used for madder), and tin-salts. 
 
 The steam-yellows are fixed upon wool and silk by means of a mixture of 
 alum, the chlorides of tin, and oxalic acid. 
 
 Aloes. 
 
 Aloes, or aloe resin, is the inspissated dry juice of a plant belonging to the 
 Asphodelea;, a native of the Cape of Good Hope, and cultivated in India and 
 the West Indies, as well as some parts of Southern Europe. The juice is best 
 obtained by cutting off the leaves at their bases, and causing the sap to run 
 into any suitable vessel over which the leaves are hung up. The juice becomes 
 dry by exposure to air, and is found in commerce as a resinous mass, of a 
 yellowish-brown colour, and very bitter taste. 
 
 There are several varieties of aloes, the chief being — 
 
 Cape aloes, the product of the Aloe spicata, arborescens, and lingua. 
 Socotrin aloes, the product of the Aloe socotrina, a highly-valued variety. 
 Aloe hepatica, the product of several species of aloe plants, and chiefly 
 
 imported from Greece and Egypt. 
 Barbados and Curacoa aloes, obtained from the Aloe arborescens by 
 steeping the leaves first in boiling water, and next pressing them. 
 Aloes is imported in boxes or bags, and very largely used, especially in 
 veterinary medicine. The colour of the pulverised resin is yellow to brownish- 
 
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 416 DYEING AND CALICO PRINTING. 
 
 yellow, and it emits an aromatic yet nauseous odour. The aloes contains — 
 A yellow crystalline principle, soluble in cold water, and named aloin ; a 
 resinous-looking substance, soluble in boiling water, and called aloctin. The 
 first-named substance, also known as aloes bitter, is best obtained by ex- 
 hausting Barbados aloes with cold water, after having previously mixed it 
 with sand, so as to prevent it from caking together. The solution yields, on 
 evaporation to a syrupy consistence, and after standing for a few weeks, a 
 crystalline deposit. The other varieties of aloes do not yield, when treated 
 as described, an aqueous extract of sufficient purity to obtain therefrom aloin 
 in a crystalline state. The latter substance has the following properties : — It 
 forms prismatic crystals, tasting at first sweetish, but with a very bitter after 
 flavour; sparingly soluble in cold water and cold alcohol, more readily in these 
 fluids when hot; neutral to test-paper; solutions bright yellow, becoming 
 orange upon the addition of alkalies; formula, according to Dr. Stenhouse, 
 C I7 H l8 7 . 
 
 Aloetin, or aloes resin, is viewed by Winkler as an acid, and by M. Bley as 
 a mixture of two acids : it is insoluble in cold, but readily soluble in hot, 
 water. 
 
 According to M. Ulex, commercial aloes consists, in 100 parts, of — Aloin, 
 69-2; aloetin, 25*6; albumen, 5*2. Dr. Kossmann* found that Cape aloes 
 contains chiefly two substances, one of which is soluble in water, and the 
 other insoluble therein, while both, on being treated with very dilute boiling 
 sulphuric acid, are split up into glucose and several resinous substances, 
 which act as acids. He finds that the aloetic principle is very readily 
 oxidisable, especially so in the presence of alkalies. The composition of the 
 soluble portion of the aloes is Ci 7 H2 2 IO , and by being split up by sulphuric 
 acid it yields aloeretic acid, being a resinous matter, formula C i5 H io 7 , and 
 aloeretin, C15H24O20. which the above-named author considers as a product of 
 the oxidation of aloeretic acid. 
 
 The aloin of Stenhouse is the substance which is primitively present in the 
 lactiferous vessels and cells of the Aloe spicata, and is originally a crystalline 
 and almost colourless substance, but by the action of air, water, and heat, 
 becomes brown and amorphous.! This substance, insoluble in water, has, 
 according to Dr. Kossmann, the composition C 5I H6 02 7 , and on being treated 
 with boiling dilute sulphuric acid it yields glucose and aloeresinic acid, 
 CijH^Og. The aloin as originally present in the juice of the plant, 3C I7 His0 7 , 
 yields, by hydratation and oxidation, products insoluble in water, and others 
 soluble : — 
 
 3 C I7 H l8 7 + 0., + 6H 2 = 3C I7 H220 I o; 3Ci 7 H l8 7 +03+3H20 = C 5I H6o0 27 . 
 
 Soluble aloin, Insoluble aloin. 
 
 When treated with nitric acid, aloin yields several nitrated coloured com- 
 pounds, and in the first place aloetic acid — prepared by heating, upon a water- 
 bath, 1 part of aloes of commerce with 8 parts of nitric acid (sp. gr. 1*31) : the 
 vessel containing the mixture is withdrawn from the water-bath as soon as 
 
 * " Journal de Pharmacie et de Chimie," September, 1861. " Repertoire de Chimie Pure," 
 vol. v., 1863, p. 530. 
 
 t Our readers may be reminded that the ornamental plant commonly called aloe by nursery- 
 men is not an aloe, but an Agave, and entirely different from the aloe here spoken of. 
 
ALOES. 
 
 4i7 
 
 effervescence sets in, and when this ceases cold water is added, whereby a 
 yellow powder is thrown down, consisting of a mixture of aloetic and chry- 
 sammic acids, which may be separated by utilising the property of the latter 
 of being insoluble in boiling alcohol, or also by first converting the joint acids 
 into potassa salts, and making use of the insolubility of the chrysammate of 
 potassa in water. 
 
 Aloetic acid is an orange-yellow, crystalline, pulverulent, bitter substance, 
 sparingly soluble in cold water, more readily so in boiling water and boiling 
 alcohol. Its solutions in caustic alkalies are red, while it yields with ammonia 
 a violet solution which contains an amide. The alkaline aloetates are crys- 
 talline and soluble in water, but the other aloetates are insoluble. The 
 formula of aloetic acid is C 7 H 2 (N0 2 ) 2 0. 
 
 When aloes is treated with an excess of boiling and concentrated nitric acid, 
 it is converted into chrysammic acid, C7H 2 (N0 2 )20 2 . According to Dr. Sacc* 
 this acid is prepared for industrial purposes as follows : — 8 kilos, of nitric acid 
 (sp. gr. 1*31) are heated on a water-bath, with the addition of 1 kilo, of aloes 
 in lumps : when the effervescence at first ensuing is finished, another kilo, of 
 nitric acid is added, and the heating is continued as long as any gas is given 
 off; the liquid is then poured into cold water ; the acid, which separates as a 
 flocculent matter, is washed first by decantation, and next on a filter, until the 
 filtrate begins to assume a purplish colour: the quantity of chrysammic acid 
 obtained amounts to about 45 grms. : there are also oxalic and picric acids 
 formed during this reaction. 
 
 Chrysammic acid is a crystalline, beautifully golden-yellow substance, 
 almost insoluble in cold water, to which it imparts, however, a fine purple 
 colour; it is readily soluble in alcohol and ether; the chrysammates are 
 sparingly soluble in water, and when crystalline display a golden-greenish hue. 
 Chrysammic acid explodes if suddenly heated ; sulphuric acid decomposes it, 
 causing an abundant evolution of gas and the production of a violet substance, 
 which, by the addition of ammonia, yields an insoluble blue and a similarly 
 coloured soluble matter. The alkaline sulphides convert chrysammic acid, in 
 potassic solution, into a blue crystalline compound (hydrochrysamide), inso- 
 luble in water and alcohol. Ammonia forms, with chrysammic acid, two 
 amides, viz., chrysamide, a crystalline brownish-red substance, with a metallic 
 hue, and chrysamidic acid, a deep olive-green matter. 
 
 The first attempts to apply industrially the colouring matters contained in 
 aloes, and those which are its products of decomposition, were made in 
 France, by Boutin in 1840, E. Robiquet in 1847, anc * Sacc in 1854. The 
 results obtained may be summarised as follows : — An aqueous decoction of 
 aloe yields, upon cotton, with acetate of alumina as mordant, and followed 
 by steaming, a pale nutty colour ; upon wool, a canary-yellow ; with pyro- 
 lignite of iron this decoction gives upon cotton a deep nut-colour, upon wool 
 a bright bistre-brown ; with aluminate of soda the decoction produces upon 
 cotton a very bright nut-colour, and with stannate of soda a bright dust-grey 
 colour. When aloes decoction and nitric acid or ammonia are mixed, wool is 
 dyed a deep brown ; aloetic acid yields upon wool a full deep brown colour, 
 which becomes brighter by being passed through a very weak solution of 
 bichloride of tin, and turns deep bistre-brown when passed through a solution 
 
 Bulletins de la Soc. de Mulhousc," vol. xxvi., p. 149 and following. 
 
 2 E 
 
■ 
 
 wBBBBBBBBBBBH 
 
 HhHIHvHBBBhHhHbI 
 
 BBBEBH1 
 
 418 
 
 DYEING AND CALICO PRINTING. 
 
 of protochloride of tin. A solution of aloetate of ammonia yields upon wool 
 a deep moss-green colour, and upon cotton a mouse-grey colour, which resists 
 washing with soap : when bichloride of tin is added to this bath, wool is coloured 
 deep bistre-brown ; and with addition of acetate of alumina the same bath 
 produces upon wool a good moss-green, and upon cotton a good grey colour. 
 When woollen fabrics are steeped in a solution of aloetate of ammonia, and 
 dried in the air, a solid green is produced. 
 
 Chrysammic acid by itself dyes wool a deep rich brown and silk a purplish- 
 brown ; chrysammate of soda dyes wool cinnamon-brown ; with aluminous 
 mordants chrysammic acid yields a beautiful violet, which, however, does not 
 resist soap well. Previously stannated cotton tissues are dyed grey by chry- 
 sammic acid, while upon the same fabric without any mordant at all it yields a 
 nut-colour; chrysammate of ammonia yields, with the addition of bichloride 
 of tin, a salmon upon cotton. 
 
 It does not appear that at present either aloes or chrysammic acid are used, 
 and in this country their application has never been extensive. 
 
 Turmeric. 
 
 The substance known in commerce as turmeric root is the underground 
 stem (tuber) of a plant belonging to the Scitamineae, and botanically known 
 as Curcuma tinctoria or longa. The shape of this article of commerce, which 
 grows in a wild state in some parts of China and India, is sometimes cylin- 
 drical, but more frequently ovoid ; its epidermis is yellowish-grey, while 
 within the colour is a bright yellow ; it emits a strong odour, and its taste is 
 peppery, aromatic, and bitter at the same time. 
 
 The plant producing this root is cultivated in Java and Bengal, the latter 
 country producing the better quality. 
 
 According to the Japanese there exists a variety of turmeric, known by them 
 as Yo-kin, yielding a root of about the thickness of a finger, and only about 
 an inch in length, and distinguished externally by transverse stripes of a 
 brownish hue. 
 
 Turmeric contains, according to Vogel and Pelletier, ligneous matter, starch, 
 and a yellow colouring substance ; while Dr. Schutzenberger found therein a 
 quantity of pectic acid and pectin. The colouring matter of turmeric is very 
 sparingly soluble in water, but alcohol, ether, the fatty and essential oils, 
 dissolve it readily. The alcoholic solution of turmeric is thrown down, by the 
 addition of tin crystals, as a red precipitate ; by acetate of lead, a chestnut- 
 brown ; by mercury salts, reddish-yellow ; salts of iron colour the tincture 
 brown ; alkalies turn it brown ; weak acids do not act upon the pigment, 
 which is turned red by concentrated acids. The colouring matter of turmeric 
 has received the name of curcumin. 
 
 We shall first give a brief review of the researches made upon this sub- 
 stance by Vogel, Pelletier, Schlumberger, and others, and then communicate 
 the results of certain researches just published, which in a great measure con- 
 tradict the results obtained by the chemists just named. 
 
 Curcumin may be prepared by first exhausting the pulverised turmeric with 
 water; the substance is next dried, and afterwards exhausted with sulphide of 
 carbon, which only dissolves fatty and resinous matters, but leaves the pigment 
 untouched. The residual matter is further treated either with boiling alcohol 
 
TURMERIC. 
 
 419 
 
 or alkaline lye : in the first case the alcoholic fluid is evaporated to dryness, 
 and the remaining extract taken up with ether, which dissolves the colouring 
 matter ; or, in case an alkali has been used, the pigment is precipitated by 
 hydrochloric acid, the sediment washed and dried, and next treated with 
 ether. The pigment obtained by the evaporation of the ethereal solution can 
 be further purified by re-solution in alcohol, precipitation by acetate of lead, 
 and decomposition of the precipitate so obtained by sulphuretted hydrogen. 
 The mixture of sulphide of lead and curcumin is dried and taken up with 
 ether, which, on evaporation, yields curcumin, as a translucent, amorphous, 
 cinnamon-coloured mass, which when powdered appears yellow. It is soluble 
 in ether, alcohol, alkalies, and concentrated acids, the alkaline solutions being 
 of a red-brown colour.* 
 
 M. E. Schlumberger has been the first to investigate the modifying action of 
 boracic acid upon curcumin. It is well known that turmeric paper becomes 
 brown under the joint influence of the boracic and any mineral acid, preferably 
 the hydrochloric. Ammonia turns this colour blue. When an alcoholic 
 solution of curcumin is boiled with boracic acid its colour turns orange, and 
 upon the addition of water to the previously cooled solution a vermillion- 
 coloured powder is thrown down, being a compound of the pigment with 
 boracic acid. This combination is broken up by the sufficiently prolonged 
 action of water ; the boracic acid dissolves, and there remains a yellow resinous 
 matter which differs from curcumin, inasmuch as it does not yield a red 
 colouration with boracic and hydrochloric acids, and on being dissolved in 
 alkalies gives a greenish-grey colouration. The boracic compound of curcu- 
 min dissolves with a purplish-violet colour in alkalies, but this soon turns to 
 grey. When hydrochloric acid is added to an alcoholic solution of bromo- 
 curcumin, and the fluid boiled, it rapidly assumes a blood-red tint ; on cooling 
 a new body is thrown down, while the boracic acid remains in solution. The 
 substance so deposited is first washed with dilute alcohol, next with pure 
 water, in order to eliminate all boracic acid ; the residue is dried, and next 
 dissolved in a boiling mixture of 2 parts of alcohol and 1 part of acetic acid. 
 This fluid, being filtered while hot, deposits on cooling rosocyanin, while the 
 pseudocurcumin remains in solution. By pseudocurcumin is understood the 
 organic resinoid substance resulting from the prolonged action of water upon 
 borocurcumin, just above mentioned. The rosocyanin is first dried, and next 
 treated with ether, in order to remove the last traces of yellow colouring 
 matter : thus purified, it is a crystalline substance, of a cantharides-like lustre, 
 insoluble in water, ether, and benzol, but very soluble in alcohol, to which it 
 imparts a most magnificent deep rose-red, quite comparable to fuchsin solu- 
 tions. This fluid becomes permanently yellow on being boiled. Ammonia 
 turns the alcoholic solution of rosocyanin a splendid blue, but this colour- 
 ation changes shortly into a dirty grey ; acids turn the blue ammoniacal 
 solution red again ; lime- and baryta-water yield blue precipitates in the alco- 
 holic solutions, which do not contain any boracic acid at all. 
 
 The relations existing between curcumin and rosocyanin (also called roseo- 
 cyanin) and pseudocurcumin are unknown, neither was until July, 1870, the 
 
 * "Journal de Pharmacie," vol. ii. (2). p. 20. Lepage, "Journal des Connaissances 
 Medicales et Pharmaceutiques," vol. xxvi., p. 315. " Repertoire de Chimie Appliques," vol. i., 
 
 P- 304- 
 
 2 E 2 
 
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 BBHB 
 
 MWWWWWWWWi 
 
 420 
 
 DYEING AND CALICO PRINTING. 
 
 true composition of curcumin known.* It is very probable that the phenomena 
 of colouration as exhibited by curcumin, which turns red and blue, and then 
 yellow again, under the action of comparatively weak reagents, bear a 
 relation to certain phenomena observed with flowers. 
 
 It is not impossible that the roseocyanin of M. Schlumberger is identical 
 with the red colouring matter of flowers or cyanin investigated by MM. Fremy 
 and Cloez, which latter substance is turned also blue by alkalies. If this sug- 
 gestion proves correct, on more precise investigation, turmeric could become a 
 useful source of preparation of the red colouring matter of flowers, which it is 
 very difficult to obtain by direct extraction. 
 
 Although turmeric is rich in colouring matter, its want of permanence is a 
 hindrance to its application as a dye-material. Some time back the use of 
 turmeric was almost exclusively limited to printing and dyeing silks. It is 
 now employed to a vast extent in stuff-dyeing, forming an important consti- 
 tuent in certain compound colours, especially the so-called " sour browns." 
 
 Turmeric is generally sold in powder, and is sometimes sophisticated with 
 common salt, which gives it a brighter appearance in the mass, but interferes 
 with its uses. It should be quite dry ; if damp it loses its colour, turns a 
 yellowish-brown, and dyes flat shades. The safest method of testing samples 
 is to dye equal weights of white woollen cloth with equal weights of the tur- 
 merics. The swatches are then compared, not only for depth of colour, but 
 are held up horizontally to the light and viewed along the surface. In this 
 " over-hand " position a good turmeric should show a beautiful golden lustre, 
 on the purity of which its value depends for many purposes, i.e., for yellows 
 on the cotton warps of figured table-covers. In India it is used for colouring 
 rice. It serves to make the well-known yellow test-paper for chemical use. 
 The Chinese use kiang-hoang (the vernacular for turmeric) for dyeing silk 
 yellow ; it is the cheapest yellow dye, but of course very fugitive. The dyeing 
 process is done as follows : — The pulverised turmeric is treated with boiling 
 water, and the mixture well stirred up ; the fluid, having become clear, is de- 
 canted from the dregs, and in the fluid the silk is immersed after addition of 
 lime-juice. 
 
 The colouring matter of turmeric fixes directly upon wool, silk, and cotton, 
 it being only required to put the tissue in a boiling decoction of the ware. By 
 printing on tissues an alcoholic or acetic solution of curcumin, and steaming, 
 the colour is also fixed. 
 
 M. Persoz has obtained good results by mixing an emulsion of carbonate of 
 
 a solutu 
 
 uid using 
 
 soda and Gallipoli oil 
 this mixture for printing. After drying, the fabrics are passed through an 
 acid. When a pattern is printed on silk by means of an aluminous and an 
 iron mordant, und the silk so prepared first put in a dye-beck containing 
 Brazil wood, and next in a turmeric bath, the patterns will come out red and 
 black upon a yellow ground. 
 
 We now turn our attention to the recently-made researches on curcumin by 
 M. F. W. Daube.f This author has succeeded in preparing pure and crystal- 
 line curcumin by the following process : — The root, coarsely pulverised, is first 
 submitted to a process of steaming, to get rid of the essential oil ; it is next 
 
 * " Bulletins de la Societe Chimique de Paris," 2nd series, vol. v., p. 194. 
 ■f "Berichte der Deutschen Chemischen Gesellschaft zu Berlin," third year, p. 609 and 
 following. 
 
CHINESE YELLOW DYES. 421 
 
 washed with boiling water as long as that fluid becomes coloured ; the material 
 is then strongly pressed, and dried. The dry residue is treated with boiling 
 benzol, which, on cooling, deposits crude curcumin. The author finds it abso- 
 lutely necessary to use benzol, although it is a bad solvent for curcumin, 1 part 
 requiring 2000 parts of boiling benzol for solution ; but only by its use is it 
 possible to prevent the solution of a resinous matter present in the root. The 
 crude curcumin so obtained is dried by pressure between folds of blotting- 
 paper, and next dissolved in alcohol, whereby a small quantity of a yellow 
 flocculent matter remains undissolved : the alcoholic solution is filtered, and 
 next precipitated by means of an alcoholic solution of acetate of lead ; the red 
 precipitate of plumbo-curcumin is first washed with alcohol, next decomposed 
 by means of sulphuretted hydrogen, after having been suspended in water ; 
 the pigment, curcumin, remaining mixed with the sulphide of lead, is extracted 
 by means of boiling alcohol, and this solution, having been left to evaporate 
 spontaneously, leaves curcumin as a prismatic crystalline body, incapable of 
 sublimation. It fuses at 165 , and is decomposed when heated to a higher 
 temperature. Curcumin is most soluble in alcohol and ether ; concentrated 
 mineral acids dissolve some curcumin, but do not leave it unchanged. Alkalies 
 dissolve it, the solutions exhibiting a bright red-brown colour ; acids re- 
 precipitate the curcumin. With compounds of lime and baryta, curcumin 
 yields reddish-brown precipitates. The formula of curcumin is Ci Hi O 3 , and 
 that of the lead compound C 20 Hi8PbO. When treated with nitric acid, cur- 
 cumin yields oxalic acid. The curcumin obtained by the author exhibits, in a 
 high degree the reactions above mentioned with alkalies and boracic acid. 
 The author has obtained rosocyanin from his pure curcumin, but his researches 
 in this direction are not yet complete : the substance hitherto known as cur- 
 cumin, and above described, is, according to the author, a mixture of resinous 
 matters and curcumin. 
 
 Yellow Colouring Matters of Chinese Origin. 
 
 Dr. Rondot, in his work on the Chinese-green, enumerates the following 
 yellow dye-wares of vegetable origin as more particularly used in China : — 
 
 The Hohang-teng (yellow-weed) is a kind of reed or rush, of from o - oio to 
 0-015 metre diameter; its taste is bitter; its shape cylindrical and knotty; 
 externally the colour is reddish-brown, internally bright yellow. This substance 
 seems to be the produce of the Menispermum tinctorium or of the Cocculus 
 fibraurea tiuctoria (tien-sien-tan of the Chinese and the cayvang-dang of the 
 Cochin Chinese). This substance yields its colouring matter to boiling water, 
 and dyes tissues without any mordant. It is used to give a ground to fabrics 
 intended to be dyed yellow with safflower. 
 
 The Hoang-pc-pi, the bark of the hoang-pe-mou, in all probability the bark 
 of the Pterocarpus Jiavus or of a species of Hymenolobium, is a tree growing 
 to great height in some parts of China. This ware likewise yields its pigment 
 to water, and dyes cloth a reddish-yellow. 
 
 The Ti-lioang is the root of a plant, probably the Rhamnesia sinensis. Its 
 colour is similar to that of our common carrot internally. 
 
 Wongsky, Wongshy, Wongschy, Hoang-tcliy, is the fruit of the Gardenia 
 grandi flora, a substance which has been investigated by Stein,* Von Orth,t 
 
 * " Chem. Pharm. Centralblatt," No. 9, p. 140. 
 t " Ncues Repcrtorium iiir Pharm., iv., 12 — 17. 
 

 BBBBSHKB 
 
 BBS 
 
 422 
 
 DYEING AND CALICO PRINTING. 
 
 F. Rochleder,* and also Th. Martius Mayer. According to Dr. Rochleder it 
 contains pectin, rubichloric acid, tannin, and a yellow colouring matter iden- 
 tical with the crocin present in saffron (Crocus sativus). This pigment is 
 obtained by exhausting the wongshy with boiling alcohol, and concentrating 
 the liquid by evaporation, followed by nitration. The alcoholic tincture is then 
 diluted with much water, and there is added gelatinous alumina. After a few 
 days standing the liquid is again filtered, and the filtrate precipitated with 
 acetate of lead. The precipitate thus formed is washed with cold water, and, 
 after having been suspended in water, is decomposed by sulphuretted hydrogen. 
 The colouring matter is extracted from the sulphide of lead by means of 
 alcohol, the liquid evaporated to dryness and taken up with water, by which 
 the colouring matter is left undissolved as an amorphous rose-coloured body, 
 about which more will be said under " saffron." 
 
 Wongshy is used in China for dyeing yellow, and also as a ground for green 
 dyes, and for imparting a first colour to silk and cotton which are intended to 
 be dyed cherry-red, scarlet, or crimson, with safflower. The colours thus ob- 
 tained are faster and brighter. Wongshy is not much used as a dye-material 
 in this country : it produces shades of yellow and orange upon woollen and 
 silk which do not appear to be possessed of much stability. 
 
 The late M. Persoz made some experiments with the colouring matter of 
 the hoang-tchy, which he obtained from the late celebrated botanist Dr. Mar- 
 tius. Persoz exhausted the fruit first with sulphide of carbon, which takes up 
 a fatty matter ; next with wood-spirit (methylic alcohol), which dissolves the 
 colouring matter, leaving it on evaporation as a reddish crystalline residue, 
 soluble in water. This colouring matter dyes cotton, mordanted with alumina 
 or oxide of tin, a yellow colour ; with oxide of iron an olive colour is obtained. 
 This colouring matter dyes silk directly without any mordant. The decoction 
 of the fruit was used, and to each litre thereof were added 2 grms. of alum 
 and 1 grm. of oxalic acid ; temperature, 40° to 50 : the shade obtained is 
 pure yellow, not affected by acids or alkalies : wool is dyed similarly, with the 
 addition to the bath of a tin-salt, or the wool may be first alumed. 
 
 The name of hoang-tchi applies to the yellow colouring principle of saf- 
 flower, which is extracted by first placing the safflower (previously tied in bags) 
 in pure water, and squeezing it by stamping on it with the naked feet ; and next 
 by placing it in sour rice-water. The yellow juice thus obtained is employed for 
 imparting a ground to silk intended to be dyed scarlet and red. Since Chinese 
 safflower is not brought into commerce until after it has been treated as just 
 described, it is clear that the ware imported from China is almost entirely de- 
 prived of its yellow colouring principle. According to the Chinese the fastness 
 and beauty of their safflower-dyed fabrics is due to the fact that they first dye 
 these fabrics a yellow colour, as just mentioned. 
 
 Saffron. 
 
 What is known as saffron is the pistils and stigmata of the flower of the 
 
 Crocus sativus, a bulbous plant of the liliaceous order, which is a native of 
 
 Southern Europe, and cultivated — for its use in pharmacy and as a condiment 
 
 — in Spain, Southern France, Austria, Greece, and England. This ware contains 
 
 t " Neues Repertorium fur Pharm.,'' iv., 365—367. " Dingler's Polytechnisches Journal,'' 
 cxiv., 136. " Repertoire de Chimie Appliq .," i., 87. 
 
BARBERRY BARK. 
 
 423 
 
 a pigment identical with that already described as present in the wongshy, 
 or fruit of the Gardenia grandiflora. The colour of saffron may be obtained 
 from it by first exhausting with ether, whereby fatty and resinous matters are 
 removed, and treating the residue with water ; the aqueous solution is preci- 
 tated with acetate of lead, and the precipitate is treated as directed for that 
 similarly obtained from wongshy. 
 
 Crocin is a rose-coloured inodorous powder, which turns brown by heat, and 
 is decomposed at 200 ; it is soluble in water, alcohol, and alkaline solutions, 
 imparting to them an orange colour. Crocin is hardly soluble in ether ; strong 
 sulphuric acid dissolves it, the liquid assuming first a blue, next a violet colour. 
 Boiling with dilute sulphuric acid splits crocin up into glucose and crocetin, 
 an amorphous deep red substance, almost insoluble in water, but soluble in 
 alcohol. Its formula is stated to be C^H^On. 
 
 Barberry Bark. 
 
 The substance known as barberry bark and root is obtained from the 
 Bcrberis vulgaris, a native shrub of Central Europe, and growing wild even in 
 India : it is used as a dye-material, and contains a yellow pigment, chiefly 
 accumulated in the bark, but met with in the wood as well as the root of the 
 shrub, which latter bears some likeness in outward appearance to ipecacuanha. 
 The colour of the root is yellowish, and its taste bitter. The colouring prin- 
 ciple of the barberry differs very essentially from the other yellow dies, inas- 
 much as berberine is a nitrogenous substance, — in fact, an alkaloid, — and is 
 also met with in Colombo root, in the root of Cocculus pahnatus, and also, 
 according to M. Dyson Perrins, in the Hydastis canadensis, to the extent of 
 4 per cent ; the yellow Assam wood (Woodumpar), of which the only specimen 
 present in Europe is at the India Museum ; a peculiar root from Rio Grande, 
 Brazil ; the yellow bark from Bogota (7 per cent), from the Pachnelo, a vege- 
 table product:, of which only one sample exists at the Kew Botanical Museum ; 
 the Coptis tecta, or Mahmira, a ranunculaceous plant, native of Hindostan and 
 China (8 per cent). 
 
 The substance which MM. Chevallier and Pelleton extracted from the 
 Xanthoxylum clava Herculis, a shrub belonging to the Rutaceae, is nothing 
 else than berberine. Berberine may be obtained from the root by adding, to a 
 previously concentrated aqueous decoction, alcohol, which precipitates foreign 
 matters. The liquid is filtered, and the alcohol removed by distillation ; after 
 some time the concentrated fluid deposits yellow needles of berberin, which 
 are purified by re-crystallisation from water. 
 
 The commercial extracts of barberry root and bark deposit, on standing, 
 crystals of berberine, which the root contains to an amount of 1*3 per cent. 
 
 Berberine has the following properties : — It forms yellow, silky, needle-shaped 
 crystals, soluble in 500 parts of water at 12 , very soluble in hot water and hot 
 alcohol, insoluble in ether ; its salts are yellow, and generally not very soluble ; 
 nascent hydrogen converts it into a colourless basic substance, C 20 H 2I N0 4 , 
 hydroberberin ; a dilute solution of iodine in iodide of potassium precipitates 
 the alcoholic solutions of the salts of berberine, producing green, mother-of- 
 pearl-like, shining, scaly crystals, which resemble chrysanilin, and, like that, 
 fix upon fibres without the use of mordants. 
 
 The root and concentrated liquid extracts of barberry are employed for 
 
Jf-W' 
 
 HHH 
 
 " 
 
 424 
 
 DYEING AND CALICO PRINTING. 
 
 dyeing silk yellow ; the colour produced is pure, 
 tion of the root in the dye-beck. 
 
 Alum is added to the decoc- 
 
 Yellow Colouring Matters contained in Flowers. 
 
 Fremy and Cloez have studied the yellow colouring matters contained in the 
 petals of flowers, and have found that they contain two pigments, viz., xanthein, 
 soluble in water, and xanthin, insoluble : the last-named substance is best 
 obtained from the petals of the sunflower [Helianthus annuus), which are ex- 
 hausted with boiling alcohol, from which, on cooling, is deposited the yellow 
 pigment mixed with fatty matters, which latter are removed by saponification. 
 The soap having been decomposed by an acid, the yellow fatty acid is 
 exhausted with cold alcohol, leaving the xanthin as a residue. 
 
 Xanthin is an amorphous resinous body, soluble in alcohol and ether, and 
 probably identical with the pseudocurcumin of M. Schlumberger. 
 
 Xanthein, very soluble in water, is readily obtained from yellow dahlia 
 flowers, which for this purpose are first exhausted with alcohol, evaporated to 
 dryness, and the residue taken up with absolute alcohol. This solution is 
 first diluted with water, next precipitated with acetate of lead, the ensuing 
 precipitate suspended in water, decomposed by dilute sulphuric acid, the 
 sulphate of lead removed by filtration, and the liquid evaporated to dryness. 
 The xanthein thus prepared is readily soluble in water, alcohol, and ether ; 
 alkalies turn the colour a deep brown, but acids restore the yellow again. 
 Xanthein yields coloured lakes with most of the metallic oxides, and dyes 
 bright yellow shades on tissues. 
 
 M. E. Schwartz has tried several dyeing experiments with various vegetable 
 products, — among these the blossoms of potatoes, lime-tree leaves and flowers, 
 willow, poplar, horse-chestnut, oak, and other leaves, — with the view to ascer- 
 tain whether these substances might answer as yellow dyes with aluminous 
 mordants, but the results were not encouraging. The finest colours, and 
 also the richest as regards yield of pigment, were horse-chestnut leaves and 
 potato blossom (flowers of Solatium tuberosum) ; walnut leaves yield an orange- 
 yellow. 
 
 It should be observed that there exist, in almost all parts of Europe, a large 
 number of plants, the bloom or flowers of which contain a sufficient quantity 
 of yellow colouring matter to be used for dyeing purposes, especially for olive 
 colours ; as an instance we name sage (Salvia colorans). 
 
 Carotin, Yellow Colouring Matter of Carrot Roots (Daucus Carota). 
 
 This dye has been investigated by Robiquet, Regnault, Zeise, and Huse- 
 mann. The latter prepares carotin by exhausting the previously pulped and 
 rasped root with water; the liquid is precipitated by tannin and a small quan- 
 tity of sulphuric acid ; the ensuing pasty precipitate is filtered, washed, 
 pressed, and next exhausted with boiling alcohol at 80 per cent, which takes 
 up mannite and a white-coloured substance, hydrocarotin, d8H 30 0. The 
 residue, insoluble in alcohol, is treated with sulphide of carbon, the ensuing 
 solution evaporated, and the dry residue treated with absolute alcohol. This 
 solution yields, on concentration, a precipitate of carotin as a brown-red, crys- 
 talline, bulky substance, with a metallic reflex. It is soluble in benzol and 
 sulphide of carbon, but insoluble in water and alcohol. This body becomes 
 
INDIAN YELLOW. 425 
 
 decolourised by exposure to light, and also by the action of heat. Sulphuric 
 acid dissolves carotin, forming a violet solution ; sulphurous acid colours 
 carotin indigo-blue. Formula, C18H24O. 
 
 Purrhee, or Indian Yellow. 
 
 Purrhee has been of late years imported into Europe, chiefly from India and 
 China. It appears to be of animal origin, and to consist of intestinal concre- 
 tions or urinary calculi, or deposits from the camel, elephant, and buffalo. 
 
 Purrhee is partly soluble in water, and is, on nearer investigation, found to 
 be the magnesia-salt of a yellow-coloured sparingly soluble acid, named 
 euxanthic acid, which may be prepared by first washing the dye-stuff with hot 
 water; the residue (euxanthate of magnesia) is dissolved in dilute boiling 
 hydrochloric acid, from which, on cooling, the euxanthic acid crystallises in 
 needle-shaped crystals ; sparingly soluble in cold, more readily in hot, water, 
 also in hot alcohol, from which the acid is deposited again on cooling. 
 
 The formula of this acid is C^H^On. By dry distillation, and also by the 
 action of strong sulphuric acid, it is converted into euxanthon, C 20 H I2 06, a 
 yellow substance, sublimable in needle-shaped crystals ; sparingly soluble in 
 cold water and alcohol, but more so in the latter liquid when boiling. 
 
 Cotton, previously mordanted with alumina, is dyed yellow in a bath made 
 up with purrhee water and borax or sal-ammoniac ; silk is dyed yellow when 
 immersed into a solution of purrhee in borax, the colour obtained being 
 sulphur-yellow. Euxanthate of magnesia (i.e., the main constituent of purrhee) 
 may also be decomposed by nitric acid not used in excess, and the aqueous 
 solution of that fluid may be applied in the dye-beck without the addition of 
 other substances : the colour thus obtained is apricot-yellow. 
 
 Yellow Colouring Matters of the Lichens. 
 
 Chrysophanic, Vulpic (Chrysopicric), and Usnic Acids. — We have al- 
 ready seen that some kinds of lichens contain colourless acids, capable of 
 yielding, under the joint influences of ammonia and air, coloured substances. 
 Other kinds of lichen contain ready-formed yellow dyes. Herberger, Rochleder, 
 and Heldt, have extracted from the wall lichen (Parmelia parietina) a yellow 
 acid (chrysophanic), largely found in the rhubarb root (Rhetim pahnatum), and 
 in the Rumex patientice and Rumex obtusifolius ; and Dr. Stein has obtained 
 from the lichen just named a yellow principle (chrysopicrin) identical with 
 vulpic acid, obtained by Mueller and Strecker from a variety of Norwegian 
 lichens (Citraria vulpina, Evernia vulpina), and by MM. Bolley and Kinkelyn, 
 the Evernia vulpina from the Alps. Usnic acid — found by MM. Knop, Roch- 
 leder, and Heldt, in the Usnca florida, Usnea hirta, Usnea plicata, Usnea 
 barbata, Cladonia rangiferina, Parmelia pnrpuracea, and Ramolina calicaris 
 — completes the list of the yellow substances produced by lichens, all of which 
 have great similarity with each other. The yellow-coloured matter found by 
 M. Picard* in the leaf-buds of the poplar tree (Populus nigra, Populus pyrami- 
 dalis), and named chrysinic acid, approaches vulpic acid. 
 
 Since the yellow-coloured acids of the lichens are scarcely soluble in water, 
 but readily soluble in alcohol, ether, and alkaline solutions, from which these 
 acids may be obtained in a crystalline state, the process of extraction from the 
 
 * " Journal fur Praktische Chemie," xciii., 369. 
 

 SBB 
 
 426 
 
 DYEING AND CALICO PRINTING. 
 
 raw material cannot be difficult. The lichens are best treated with an alkaline 
 lye, and then precipitated by an acid ; the precipitate thus obtained is dissolved 
 in alcohol or ether, and these solutions left to crystallise. 
 
 Chrysophanic, Rumicinic, or Rhubarbaric Acid, also called Lapathin.* 
 — Formula, Ci H80 3 . Yellow needle-shaped crystals, which turn red by the 
 action of nitric acid, and dissolve in concentrated sulphuric acid, yielding a red 
 solution. It also dissolves in caustic potassa, yielding likewise a red liquid, 
 which on evaporation deposits a blue flocculent matter, soluble in water, and 
 then again producing a red solution. This acid is decomposed when strongly 
 heated, yielding a yellow flocculent sublimate. 
 
 Vulpic Acid. — Chrysopicrin, scarcely soluble in water, either hot or cold ; 
 soluble in 588 parts of cold and 88'3 parts of boiling alcohol, and soluble in 
 ether; fuses at no°; sublimes at 120 ; the sublimate forms brilliant golden- 
 yellow, scaly particles, soluble in alkaline liquids. This solution is not acted 
 upon by air ; when treated with hypochlorite of lime it yields an oily liquid 
 and a red resin. This acid does not yield good results in dyeing. 
 
 Usnic Acid is a scaly, crystalline yellow substance, insoluble in water, 
 sparingly soluble in boiling alcohol, soluble in ether and alkalies. These last- 
 named solutions become carmine, and at last black, on exposure to air. If 
 submitted to dry distillation this substance yields beta orcin. 
 
 Chrysinic Acid above mentioned is of no importance at all, and hitherto 
 none of these substance have been applied industrially. 
 
 Gentianic Acid. — The well-known gentian root contains a yellow acid, 
 forming needle-shaped crystals, sparingly soluble in water, more readily so in 
 alcohol and ether ; with alkalies it yields golden-yellow crystallisable salts ; 
 nitric acid converts it into a green insoluble substance, which appears to be 
 nitro-gentianic acid. 
 
 Annatto, or Anotto, also known as Rocon, Bixin, or Orleans. 
 
 Annatto is mainly the pulp which surrounds the fruit of the Bixa orellana, 
 a shrub native of South America, and cultivated in Mexico, Brazil, Guiana, 
 and the Antilles. When the fruit has reached maturity the fruits are gathered, 
 the seeds pulled from the capsules and coarsely pounded up with the pulp 
 while placed in water, and left to ferment for several weeks. After this time 
 the pulp and liquid are passed through a sieve; the colouring matter soon 
 settles to the bottom of the liquid, and having been collected is evaporated by 
 heat, put in boxes, and dried in the sun. 
 
 Annatto is imported into Europe in the shape of cakes, weighing from 5 to 
 8 kilos., packed in banana leaves (Guiana anotto), or as cakes packed in casks 
 (from Brazil), or in tinned iron boxes from Cayenne. This latter kind is about 
 twice as rich in colouring matter as the ordinary annatto of commerce ; its 
 colour is bright, its smell pleasant; it contains about 5 per cent of mineral 
 matter, and from 67 to 70 of water. f It has been regularly manufactured at 
 Cayenne since 1837 by M. Daubriac. 
 
 In the year 1848 Dumontal introduced an improved mode of preparation of 
 
 * " Annalen der Chemie," cvii., 324. " Repertoire de Chimie Pure," iv., 371. "Journal fur 
 Prakt. Chemie," lxxxiv., 43G. 
 
 + " Girardin, " Memoire sur la Bixin." "Journ. de Pharm. et de Chimie," xxi. 174 [3]. 
 Girardin, "Memoire sur la Falsification du Rocon." "Journal de Pharmacie, Cahicr de 
 Mars," 1836. 
 
AN NAT TO. 
 
 427 
 
 annatto, whereby the fermentation is evaded, and the pulp simply washed out 
 from the capsules, and off the seeds. In this way a product is obtained from 
 five to six times more valuable than the ordinary annatto, and the product has 
 become known as bixin, since it yields better and purer shades. The ordinary 
 annatto of commerce is a homogeneous unctuous paste, of a dull yellowish 
 red externally, more bright internally, and giving off a disagreeable urinous 
 smell. It contains on an average — Water, 72 per cent ; leaves and other foreign 
 organic matters, 22 per cent ; colouring matter, 6 per cent. The annatto as 
 usually met with in trade is frequently adulterated, either designedly, or by 
 ignorant preparation, with red- or yellow-coloured mineral matters, as ochre, 
 colcothar, ground-up bricks. These impurities are detected by drying the sub- 
 stance first at ioo°, and then igniting it in a platinum crucible. Annatto of 
 good quality does not yield more than from 8 to 13 per cent of ash, of a 
 yellowish colour. As regards the quantity of real colouring matter contained 
 in annatto, this varies according to the quantity of water present, which is 
 estimated by drying at ioo° about 10 grms. of the substance. The colouring 
 matter is estimated by a dyeing process, for which M. Girardin gives the 
 following instructions : — For cotton he takes of previously dried (at 100°) and 
 ground annatto, 5 grms. ; carbonate of potassa, 10 grms. ; water, 400 grms. 
 For silk — Annatto, 0*5 grm. ; carbonate of potassa, 1 grm. ; water, 200 grms. 
 The mixture is heated to boiling, along with 12 grms. of cotton-thread or yarn, 
 or 2 grms. of skein silk; the ebullition is continued for fifteen minutes ; the 
 vessel is then removed from the source of heat, and left standing for an hour; 
 the yarn is then taken out, squeezed, and dried in the shade. This assay is 
 made in comparison with a standard sample. 
 
 The colouring matters of annatto have been investigated by Chevreul,* 
 Bousingault.t Kernot,+ Picard,|| Bolley, and Mylius§. When treated with 
 water, annatto yields a yellow colouring matter, soluble in water and alcohol, 
 insoluble in ether, and capable of imparting a yellow colour to tissues pre- 
 viously mordanted with alum. The colour has been named orellin. The 
 residue, after exhausting the annatto with water, contains its chief colouring 
 matter, bixin, which may be obtained, according to Bolley, as follows : — 
 Cayenne annatto is first washed with water and dried, next exhausted with 
 very strong boiling alcohol ; the tincture is filtered, and then evaporated on a 
 water-bath ; the residue digested with ether, which dissolves a portion thereof, 
 leaving a cinnabar-red powder, fusible at ioo°, soluble in alcohol, but insoluble 
 in water ; not affected by a heat of 145 , nor by boiling with dilute sulphuric 
 acid, soluble in weak alkaline solutions, and in soap-water, exhibiting a yellow 
 or orange-yellow colour. According to Dr. Bolley, the formula of this substance 
 is C 5 H60 2 ; the matter soluble in ether has not been further investigated. 
 
 According to Kerndt, there is left on the evaporation of the ethereal solution 
 a substance which fuses at ioo°, and the formula of which should be Ci 2 H 22 0. 
 Picard considers this to be an error, stating that the product is a mixture of 
 substances, including fatty matters. The impure bixin (obtained as above 
 
 * " Lecons de Chimie Appliquee & la Teinture. 
 t " Annalcs de Chimie et de Physique [2], xxviii., 440. 
 
 } " Jahresbericht der Rcinen und Angewandten Chemie," &c, by Liebigand Kopp, 1849^.457 
 H Schweitzerische, " Polytechnische Zeitschrift," 1861. " Rcpert. de Chimie Appliquee," 
 1S61, 419. 
 § Schweitzerische, " Polytechnische Zeitschrift," ix,, 134 
 
428 DYEING AND CALICO PRINTING. 
 
 described) is first dissolved in alcohol, soda solution is next added, and the 
 alcohol distilled off; the liquid is then shaken up with ether, which extracts a 
 soft fatty matter, and afterwards treated with carbonic acid, whereby a soda- 
 soap is precipitated. Acetic acid is then added to neutralise the alkali, and 
 the ensuing precipitate of organic matter is treated with ether, which, on 
 evaporation, yields an amorphous blood-red pulverulent substance, sparingly 
 soluble in ether and alcohol when cold, but soluble in boiling alcohol and 
 in benzol. As this substance is not fusible at ioo°, orellin is, according to 
 Dr. Kerndt, derived from bixin, by having become altered by the action of air 
 and water. Concentrated sulphuric acid dissolves bixin as well as annatto, 
 yielding a deep blue-coloured liquid. From these particulars it will be evident 
 that the chemical history of annatto is very incomplete. 
 
 Annatto is used in dyeing and printing tissues, and for colouring oils, grease, 
 butter, cheese, and varnishes. The shades yielded by annatto upon tissues 
 are bright, and resist the action of acids and soap; but though even chlorine 
 scarcely affects this dye, it fades on exposure to light and air. When annatto 
 is used alone it yields bright orange-red or orange-yellow colours, and it is 
 sometimes used to enhance the brightness of other dyes which produce red, 
 yellow, orange, or pink. In order to dye cotton with this ware it is first dis- 
 solved in carbonate of potassaor soda, the liquor boiled, or in some instances 
 (according to the nature of the fabric) heated to 6o° ; the goods dyed are left 
 in the bath for a quarter of an hour, after which they are pressed out, and 
 washed in slightly acidified water. Better results are, however, obtained by 
 first mordanting with stannate of soda and sumach, and by nearly neutralising 
 the alkaline bath with sulphuric acid, so as to prevent the precipitation of the 
 colouring matter, and yet keep the the latter quite ready to become fixed im- 
 mediately on the fibre. For printing on cloth a solution of annatto in caustic 
 potassa is used, the tissue next aged, and then placed in either a weak acid 
 bath or in a weak solution of alum or chloride of tin. For steam colours the 
 following mixture may be used : — 
 
 Caustic soda solution (sp. gr. 1*086, containing) g litres 6 litres 
 about 7-8 per cent of actual soda . . . . J 
 
 Annatto paste 750 grms. 5 kilos. 
 
 Boil for ten minutes, and add next of — 
 
 Tartaric acid go grms. 70 grms. 
 
 Alum 350 ,, 1 kilo. 
 
 These preparations are thickened with gum or farina water, and next printed, 
 steamed, and washed. Silk requires no mordant for dyeing with annatto ; the 
 bath is made up of equal parts of annatto and crystallised carbonate of soda, 
 to which sometimes soap is added ; the temperature is 50°, and the silk is 
 worked for a quarter of an hour. The reddish yellow or deep orange shade is 
 rendered yellow-orange by rinsing the fabric through lemon-juice or a weak 
 solution of tartaric acid. 
 
 Green Colouring Matters. 
 Chinese Green. Lo-kao.* — During the first portion of the year 1848 
 D. Kcechlin-Schouch found, while examining some cotton cloth brought from 
 
 * Dinglcr's "Polytechn. Journ.," cxxvi., 23S; cxlvi.; cxlix., 140; clxv., 397. " Comptes 
 Rendus de l'Academie dcs Sciences," xxxv., 558. " Bulletins de la Socicte ti'Encouragement," 
 
LO KAO. 
 
 429 
 
 China a few years previously, that it had been dyed green by a substance un- 
 known in Europe.* A piece of this cloth having been sent to M. Persoz for 
 investigation, he found that the dye was of organic origin, and quite different 
 from any then known in Europe. The first genuine sample of the dye-ware 
 ever sent to Europe was received by M. Persoz, f through the kindness of M. 
 Forbes, then United States Consul at Canton. Shortly after this sample had 
 been sent to Paris a comparatively large quantity of lo-kao came via Batavia 
 to Holland, and having attracted the attention of the silk dyers at Lyons, was 
 sold at 533 francs per kilo. 
 
 Lo-kao is met with in commerce, or rather was, since it is now-a-days 
 almost entirely superseded by the aniline greens, in the shape of thin 
 lamina?, varying in thickness of from 1 to 4 millimetres, and from 2 to 5 centi- 
 metres square. These laminae exhibit a blue colour, with a violaceous or green 
 reflection; they are fragile, yet difficult to pulverise, becoming a pasty mass. 
 Lo-kao contains from 21*5 to 33 per cent of ash, chiefly oxide of iron, lime, 
 and alumina; 9*3 percent of water; and 6i - g per cent of colouring matter. 
 It is decomposed by heat, but does not yield any sublimate; it is insoluble 
 in alcohol, wood-spirit, sulphide of carbon, and ether. Water does not 
 dissolve lo-kao, but makes it swell up; dilute and cold acetic, hydrochloric, 
 sulphuric, and tartaric acids aid its solution. With the aid of heat the 
 solutions of lo-kao are rendered olive-brown by concentrated acids, an iron- 
 grey precipitate being deposited, and the supernatant liquid becomes yellow, and 
 turns orange on the addition of an alkali. Concentrated sulphuric acid 
 dissolves lo-kao, yielding a reddish brown solution. 
 
 Alkalies at first aid the dissolution of this green pigment, but when it is 
 left a long time in contact with the alkaline fluid the colour turns brown, and 
 more rapidly at a boiling temperature, being converted into a new pigment, 
 which cannot be again made green, but which has the property of becoming 
 fixed upon previously mordanted cotton. The alkaline carbonates also destroy 
 the green colour on prolonged action along with water at a pressure of from 
 2 to 3 atmospheres. 
 
 The reducing acids, such as phosphorous, arsenious.hyposulphurous, oxalic, 
 and formic, when added to lo-kao, cause the formation of a purple-violet 
 precipitate. Hydrosulphuric acid converts lo-kao and its solutions into a 
 blood-red substance, but by the action of air the liquid becomes gradually 
 green again, after having passed through a series of intermediate shades. 
 Hydrosulphuret of ammonia also reduces and energetically dissolves lo-kao. 
 Protochloride of tin dissolves lo-kao largely, and turns its colour blood-red. 
 
 liv., 415; lv., 290. "Repertoire de Chimie Appliquee," 1., 11, 75, 78, 370; ii., 53 ; iv., 405. 
 Buchner's " Repertorium," viii., 69. " Bulletin de la Societe Industrielle de Mulhouse," 
 xxv., 96. "Notice du Vert de Chine et de la Teinture en Vert chez les Chinois," par M. 
 Natalis Rondot ; suivie ri'une " Etude des Proprietes Chimiques et Tinctoriales du Lo-kao," 
 par M. J. Persoz ; et de " Recherches sur la Matiere Colorante des Nerpruns Indigenes," par 
 M. A. F. Michel. Paris: chez Lahure et Co., 1858. 
 
 * Letter from the Chamber of Commerce of Mulhouse to the then Minister of Commerce, 
 &c, viz., M. Dumas, 27th April, 1850. 
 
 t This is the statement as found in the published papers above quoted, but from a private 
 communication we know with perfect certainty that a sample of the dye was brought over along 
 with the cloth. 
 

 430 
 
 DYEING AND CALICO PRINTING. 
 
 The primitive green colour is, however, restored by the addition of an 
 alkaline acetate, or of a strong base and simultaneous exposure to air. 
 
 Oxidising agents, such as nitric, chloric, iodic, and chromic acids, destroy 
 the Chinese green, the ultimate result being the formation of a red substance 
 different from that which is formed from the lo-kao by reducing agents, since 
 the latter is .capable of being re-converted into the original green colour. 
 Some salts, among which are alkaline phosphates, pyrophosphates, borates, 
 margarates, oleates, and stearates, assist the solution of lo-kao in water, while 
 the salts of magnesia and zinc turn its colour to a pure blue ; nitrate of silver 
 and ferricyanide of potassium oxidise the colouring matter if an alkali is 
 simultaneously present. Lo-kao possesses the peculiar property of so masking 
 the presence of certain bases, e.g., lime, oxide of iron, and others, that they 
 can only be detected after the complete destruction of the organic matter by 
 incineration. The opinion of M. Persoz on lo-kao is, that it is a mixture of 
 lime, magnesia, and iron-lakes, along with some phosphate of alumina, and 
 partly soluble in water. He gave the name of cyanin to the pure colouring 
 matter, freed as much as possible from the accompanying inorganic sub- 
 stances. It has a blue colour, and contains no nitrogen. 
 
 Persoz gives the following directions for the purification of the commercial 
 article: — (1). Lo-kao is dissolved in a saturated solution of carbonate of potassa; 
 after the liquid has lost its turbidity, water is added to the previously decanted 
 clear liquid ; after a while there is formed a green precipitate, which, after 
 being washed and drained, may be successfully used for dyeing and printing. 
 (2). Lo-kao is first soaked in water, and after it is swollen and softened it is 
 mixed with one-and-a-half times its weight of acetic acid; next 5J parts of 
 water are added, the liquid filtered, and to the filtrate ammonia is added, 
 whereby a lake far richer than the original substance is obtained. 
 
 An aluminous lake may be obtained when a solution of lo-kao, to which an* 
 alum solution is added, is precipitated by an alkaline carbonate, or also by the 
 addition of a salt of alumina to a solution of lo-kao in carbonate of soda. 
 The double chloride of ammonium and tin yields, with an aqueous or acetic 
 acid solution of lo-kao, a beautiful blue precipitate if care be taken to add . 
 acetate of soda at the same time. The purple-violet precipitate obtained by 
 the action of the reducing acids, such as arsenious and formic, is soluble in 
 acetate of lime, and that solution deposits after some time a deep blue powder, 
 verging upon violet. 
 
 As regards the origin and mode of preparation of lo-kao, the results of the re- 
 searches made in China by Father Helot ; by MM. Montigny. Edan, Arnaudtizon, 
 Fortune, Remi, Edkins, and others, coupled with the botanical investigations 
 of samples of plants sent over to M. Decaisne, prove that lo-kao requires for its 
 preparation two different plants, viz., the Rhammts utilis, called in the Chinese 
 language, hong-pi-lo-chou, and the Rhammis chlorophorus, pe-pi-lo-chou. One 
 of these shrubs grows wild, while the other is purposely cultivated, but 
 which of the two is not known with certainty. The hong-pi-lo-chou, also 
 known as hom-bi-lo-za, is said to yield by itself a deep and fast colour, but 
 void of brilliancy, while the pe-pi-lo-chou yields a weak but brilliant colour. 
 In order to render the mode of preparation of lo-kao in China properly under- 
 stood, we have first to describe the mode of dyeing the cloth by means of 
 the vegetable matters in question, the lo-kao being obtained by detaching 
 from cloth the excess of colour fixed thereupon. 
 
LO-KAO. 
 
 43i 
 
 The following is the description of the process as carried out at A-z6, and 
 witnessed by Helot: — The fresh (green) bark of the hong-pi-lo-chou is first 
 boiled with water, and left standing in that liquid for two days ; the preparation 
 of the infusion of the green bark of the pe-pi-lo-chou lasts for ten days. Each 
 of these infusions is separately employed, and when used lime-water is added. 
 The cloth is first dipped from seven to ten times in the hong-pi bath, and next 
 three times in the pe-pi bath, but the fabric is dried after each separate im- 
 mersion. This drying is effected in meadows, where the cloth is spread out 
 at about nightfall, and left until noon the next day, the action of the sun 
 being indispensable for the development of the colour, only the side of the 
 cloth exposed to the sun's rays being dyed. It is a remarkable fact that this 
 Chinese cloth thus green-dyed is very intensely coloured on one side, and 
 only faintly so on the other. This appearance induced Persoz to doubt the 
 correctness of Helot's statement, Persoz expressing himself on this matter 
 as follows : — Since the Chinese green-dyed fabrics have a right and wrong side, 
 they cannot have been dyed by immersion, but the dye has evidently been im- 
 parted to the cloth either by a brush or other mechanical means ; while, 
 moreover, the change which the colour undergoes by exposure to the sun's 
 rays proves that the dye has not been imparted in the way described by 
 Helot. 
 
 The researches, however, of M. Michel on indigenous European plants of 
 the same genus as those used in China clear up this subject, as we shall see 
 presently. The cloth dyed as above described, having become quite dry, is 
 placed in cold water, and thoroughly washed and rinsed through ; the wash- 
 waters are collected together, poured in a large cauldron, and the water is boiled 
 after there has first spread over its surface a tight network of cotton yarn, 
 upon which the colouring matter is deposited during the process of ebullition. 
 In order to collect a quantity of the colouring matter, this process of ebullition 
 has to be repeated with fresh quantities of water wherein the previously dyed 
 cloth has been washed. When the cotton yarn is sufficiently charged with 
 pigment the former is washed in cold water, and well rubbed with the hands, 
 by which means the lo-kao becomes detached, and slowly settles in the water; 
 the precipitate is washed by decantation, and the thin pasty mass of pigment 
 is placed upon paper, and dried by first absorbing a portion of the moisture 
 by means of ashes, and next dried in the sun. The layer of lo-kao while 
 drying becomes detached from the paper, and by the latter being bent the pig- 
 ment presents the aspect of the irregularly shaped, small, thin, yet hard 
 lamina? as met with in commerce. The weight of cotton yarn required to 
 exhaust the pigment from 300 pieces of dyed cloth, the length of these pieces 
 not being mentioned, is 3-62 kilos. In order to obtain the weight of 1 kilo, of 
 lo-kao, 1060 pieces of dyed cloth are required, and since, according to the 
 statements of Helot, the five manufactories of lo-kao at A-ze cannot annually 
 yield more than from 18 to 24 kilos, of lo-kao, the high price of that substance 
 is readily explained. 
 
 M. Michel, at Lyons, has experimented with the bark of the Rhamnus 
 catharticus, following the same mode of operation as that described, — that is 
 to say, placing cloth in aqueous infusions of the bark, and repeating these 
 dippings, each being followed by a drying of the cloth by exposure upon grass 
 during the night and a portion of the daytime : he obtained a rather intensely 
 

 ;S» S&3SS 
 
 
 jH W jH Bff 
 
 BBB 
 
 i— — — — 
 
 Si 
 
 432 
 
 DYEING AND CALICO PRINTING. 
 
 violet-coloured cloth, which turned green on being washed in a boiling dilute 
 solution of alum. The green dye thus obtained lacked the brilliancy and 
 intensity of the Chinese dyed cloth, but the reactions were the same, and, 
 moreover, the cloth prepared by M. Michel had a wrong and right side, just 
 as described for the Chinese cloth. The cloth dyed by M. Michel had 
 its right side there where it had been exposed to diffused light. There does 
 exist, therefore, in the Rhamnacese a peculiar substance, not yet isolated, which 
 has the preperty of becoming green under the influence of the white diffuse 
 light of the sky. 
 
 Green Dyeing. 
 
 The Chinese dye the woven tissues or yarns green either by making use of 
 the barks already mentioned, in which case the dyed fabric has — as regards 
 the colour — aright and wrong side, or they use the lo-kao, in which latter case 
 both sides of the cloth are dyed alike : this difference is readily explained by 
 the researches of M. Michel, because, as regards the first case, there is fixed 
 on the cloth a colourless but colourable matter, which does not develope its 
 colour but when exposed towards the light ; in the second case, there is used 
 a ready-formed pigment. 
 
 When the dyer desires to use the bark only, the following processes are 
 used : — 
 
 a. Process of Khiu-tcheou-fou. — The fresh bark of pe-pi-lo-chou is boiled, 
 
 and to every 100 kilos, of the liquid are added 63 grms. of Chinese pot- 
 ash ; the cloth is immersed in the liquid from two to three times, and 
 dried in the sun after immersion. At Chan-toung alum is used instead 
 of potash. 
 
 b. Process of Emou-l, as described by Mr. Sinclair. — The bark of lo-tse* is 
 
 placed in hot water, and next boiled for an hour ; potash and alum are 
 added; the liquid is next decanted and filtered, and left standing over 
 night ; the goods are next immersed in the bath, and after that dried by 
 exposure to open air, the pieces being stretched out over the grass, but 
 only during the earlier hours of the day. This dyeing and drying ope- 
 ration has to be repeated several times before the desired shade of colour 
 is obtained. 
 Lo-kao is not used in China even for dyeing more common and coarse kinds 
 of cotton goods, but only for bright colours. The pigment is dissolved in a hot 
 solution of potassa, and the previously well-washed cloth is immersed in this 
 bath, kept at a temperature of 50 or 60°. Immediately after the first immer- 
 sion the goods are wrung out by mechanical means, and the dyeing operation 
 is repeated a second time, again followed by wringing out, and next a washing 
 in fresh water and drying in the open air, which ends the proceedings. There 
 is not the least doubt that the Chinese use lo-kao for silk-dyeing, and also 
 apply the Rhamnus barks for that purpose, but their process of operating is 
 unknown. 
 
 The researches of Stanislas Julien, who was a resident in China for many 
 years, have proved that the use of the lo-kao and the bark from which it is 
 
 * Although this word differs from that mentioned under a, the material is no doubt the same, 
 it being a well-known fatt that there are very many dialects in use in China, the extent of that 
 country exceeding by one-third that of the United States of America, which measure fully 
 3,500,000 square miles. 
 
DYEING WITH LO-KAO. 
 
 433 
 
 obtained has only been known to the Chinese themselves since about thirty-five 
 years. It is quite certain, also, that no mention whatever is made of Chinese 
 green and the use of the barks, for any purpose whatever, in the otherwise 
 very-correctly written and published Chinese books on botany and agriculture 
 issued about the middle of the last century. 
 
 French Process for Dyeing with Lo-kao. 
 
 E. Michel, at Lyons, dyes silk green {Vert-Venus, Vert-Azof, or Vert- 
 Lumiere, the latter appellation being given because this green colour does not 
 appear blue when seen in artificial light) by soaking in an aqueous solution of 
 alum (sp. gr. i'034), for three days, a quantity of 5 grms. of lo-kao and 
 30 grms. of the solution just alluded to. The pigment is next thoroughly 
 incorporated with the solution of alum by stirring and rubbing with a glass 
 rod, while the fluid is simultaneously diluted by the addition of 250 grms. of 
 the alum solution ; the liquid is left again standing for twenty-four hours, and 
 then carefully decanted from any sediment. The colour of this fluid is very 
 deep green, nearly black. This operation is repeated with a fresh quantity of 
 pigment, so as to obtain at least a litre of the solution, which keeps very well. 
 M. Michel found that if to this solution of lo-kao a sufficient quantity of 
 spring water were added, containing lime salts, there ensues gradually a pre- 
 cipitate of a calcareo-aluminous lake, and he contrived to find, by a series of 
 experiments, what quantity of such spring water would be required for obtaining 
 a fluid from which this lake did not precipitate immediately, or even after a 
 length of time, but which yet possessed the property of depositing the 
 colouring matter it contains on the fibre of textile fabrics when they come into 
 contact with it. The quantity of spring water at Lyons required for 1 litre of 
 lo-kao solution was found to be 15 litres : in a solution of that description 
 silk was dyed without any other precaution than a slight deviation of tem- 
 perature, and the depth of the shade is regulated by the number of repeated 
 immersions. He found that, in consequence of the various operations silk is 
 submitted to before being dyed, it contains a small quantity of lime-salts, 
 which act in this case as a mordant ; but in some cases the silk might advan- 
 tageously be immersed in spring water containing lime before the dyeing 
 process. Instead of using the lo-kao of commerce, it is preferable to apply 
 it in the purified state prepared according to the method of M. Persoz, 
 described above. 
 
 The following is another method for dyeing with lo-kao, suggested by 
 Persoz : — The lo-kao is dissolved in a moderately strong and slightly acidu- 
 lated solution of tin-salt, and the silk is immersed in this liquid and kept at 
 the ordinary temperature : it assumes a pale salmon-colour, and is next 
 washed in a liquor made up of ammonia, potassa, or acetate of lime. The 
 colour thereby becomes first purple, and next blue, and the blue is converted 
 into green by dyeing in a cold infusion of Persian berries : the silk may, if 
 preferred, be aluminised first, and next put into a solution of lo-kao m sulphy- 
 drate of ammonia. After the immersion of the silk in this liquor it is 
 thoroughly aged, and in order to obtain the requisite depth of shade the 
 immersion is repeated once, twice, or oftener. The lo-kao may also be first 
 steeped in a weak alkaline lye, and next saturated with hydrated protoxide of 
 tin ; the silk is placed in this solution, and the fabric exposed to air, when it 
 
 2 F 
 

 BHSE 
 
 434 
 
 DYEING AND CALICO PRINTING. 
 
 turns blue by the oxidising action of the atmosphere, and is converted into 
 green by a yellow dye. 
 
 According to M. Persoz's opinion, the Chinese green-dyed cotton is, like all 
 greens of organic origin (excepting aniline green), the result of a combination 
 of blue and yellow, and he also thinks that there is no ground at all for sup- 
 posing that the green dye imparted to cotton in China and the pigment known 
 as lo-kao are identical, because in the former the yellow, and in the latter the 
 blue, predominates. This opinion is strengthened by the fact that the process 
 of dyeing of M. Michel produces upon silk a colour which is a bluish-green, 
 and only by the aid of picric acid can this be converted into a pure green. 
 
 If desired to dye cotton a green with lo-kao the following process is recom- 
 mended by M. Persoz : — From 50 to 60 grms. of white soap are dissolved in 
 10 litres of water, to which is added a sufficient quantity of lo-kao, previously 
 steeped and consequently swollen in water, or, better yet, the purified 
 pigment. The liquid so obtained is heated, and the cotton, on immersion, is 
 at once dyed. 
 
 For the purposes of printing the cotton fabric may be alumed first, but this 
 is not indispensable. The colour consists of gum-water wherein lo-kao, pre- 
 viously steeped and swollen up, is finely divided, or an aluminous lake may be 
 used, with or without the addition of acetate of alumina. Another plan is to 
 print on a thickened solution of lo-kao in tin-salt : after drying, the fabric is 
 passed through a solution of acetate of lime, to which an excess of lime is 
 added. Cotton may be dyed, also, with a solution of lo-kao in sulphydrate 
 of ammonia, followed by a well-conducted exposure to air. 
 
 M. Persoz has succeeded in fixing lo-kao on woollen fabrics by preparing 
 first a tin lake of that pigment : this lake is suspended in water, which is next 
 heated, and the wool being entered, and some drops of a solution of oxalic 
 acid added, it becomes perfectly dyed. The same lake may be thickened with 
 gum-water acidulated with oxalic acid, and printed on to woollens and 
 worsteds, yielding, after steaming, a beautifully green colour. 
 
 The beautiful shades of green as obtained from lo-kao have almost disap- 
 peared from the market, first, from their want of stability, and, secondly, 
 because of the discovery of the coal-tar colours. 
 
 Lo-kao is also noticeable as being the only substance we are acquainted 
 with capable, with proper reagents, of producing all the seven colours of the 
 spectrum. Though driven from the market, it remains an interesting sub- 
 stance. 
 
 It is an interesting fact, that while the greens produced by indigo and picric 
 acid appear blue in artificial light, those produced with Prussian blue and 
 picric acid appear green under the same conditions. 
 
 Other Green Dyes of Vegetable Origin. 
 
 We will now briefly notice some green pigments and dyes which have been 
 noticed, but are, after all, very little known in Europe, and which may be 
 identical with or analogous to Chinese green. 
 
 M. Poivre, French Minister-Plenipotentiary in Cochin China (1749), and 
 Father Horta, who visited that country as a missionary (1766), speak of a plant 
 called Tsai, which was cultivated in Cochin China and neighbouring countries, 
 and which plant, on being fermented, as indigo usually is, produced by that 
 

 CHLOROPHYL. 
 
 435 
 
 process a mealy green substance, which yielded by itself an emerald-green 
 on cloth. Since that period nothing further has been learned on this substance, 
 nor of the plant, but there is no reason at all to doubt the statements of the 
 two travellers above named. 
 
 Dinh-schan, also belonging to Cochin China, is noticed by M. Charpentier 
 de Cossigny, who resided there (1770), in the following terms : — The natives 
 of this country have a plant which they call dina-schan, and which bears some 
 resemblance to our Melissa : from that plant they obtain, by macerating it in 
 water, a green mealy substance, which is used by them for dyeing all kinds of 
 fabrics different shades of green. It is not unlikely that the pigment here 
 alluded to is the tsai above mentioned, and the plant from which it is obtained 
 is either the Mercurialis perennis, or, perhaps more correctly, as stated by the 
 Jesuit Correa, the Justicia tinctoria, belonging to the natural order of the 
 Acantheae. 
 
 Green Indigo may be obtained, according to M. Charpentier de Cossigny, 
 from the Indigo/era tinctoria, by steeping the leaves of that plant for some 
 time in fresh water, or in weak milk of lime for an hour only, and then pressing 
 the leaves and repeating the steeping process, with a fresh quantity of water, 
 for another hour : the two liquids thus obtained are poured together and 
 filtered ; lime-water is added. The filtrate is vigorously stirred about, depo- 
 siting a green mealy substance, which is first washed with lime-water, and 
 next with fresh water. The green indigo brought over from India in 1790, by 
 Prinsep, appears to have been, according to the statements and researches of 
 Bancroft, a substance analogous to chlorophyl, soluble in alcohol, and mixed 
 with some ordinary indigo. 
 
 Barasat Green was in 1793 imported from Calcutta in very small parcels, 
 said to be obtained from the Asclepias tinctoria, but in the opinion of M. Persoz 
 this substance is merely an impure and immature indigo. The same observa- 
 tion applies to the green indigo investigated by M. Kurer (1801), and to the 
 vegetable green sent from China and Java by M. Cezard (1837).* This sub- 
 stance was analysed by M. Schwartz, and found to contain, in 100 parts — 
 Yellow colouring matter, 10-40 ; gluten and salts, 35'30 ; indigo-brown, 39*20 ; 
 mucilaginous matter, 5 - io; indigo-blue, io - o. 
 
 The substance known in China as Whi-mei, and exhibited at the London 
 Exhibition of 1851, is the product- of the Sophora Japonica, the bloom of 
 which is called Hoai-hoa, and used as a green dye. 
 
 Chlorophyl ; Chromule ; Green Colouring Matter of Leaves and other 
 Green Parts of Plants. 
 
 The green colouring matter or pigment widely diffused through the vegetable 
 kingdom is, notwithstanding the many researches made by different authors, 
 as yet only imperfectly known. Some investigators consider it as a green 
 principle, while others, and among them M. Fremy, state that it is a mixture 
 of a yellow matter (phylloxanthin) and a blue pigment (phyllocymin), but the 
 chemical reagents used for the separation of the two supposed pigments are 
 powerful enough to cause the probable decomposition of a substance so readily 
 altered as chlorophyl. 
 
 M. Verdeil isolates the chlorophyl by exhausting the plant or leaves with 
 
 'Bulletin de la Societe Industrielle de Mulhouse," xi., 27. 
 
 2 F 2 
 

 436 
 
 DYEING AND CALICO PRINTING. 
 
 alcohol ; the solution is precipitated with lime, and the lime lake thus produced 
 is washed, and next decomposed by hydrochloric acid ; the acid solution is 
 shaken up with ether, which takes up the green pigment. On evaporating the 
 ether the pure chlorophyl is left. The chlorophyl thus obtained is a deep 
 green powder, unacted upon by exposure to air, not decomposed at 200 , and 
 not fusible at that temperature ; insoluble in water, but soluble in alcohol, 
 ether, acids, and alkalies : hydrate of alumina combines with this pigment, 
 and withdraws it readily from its alcoholic solution provided it be first properly 
 diluted with water. 
 
 Nascent hydrogen reduces and decolourises chlorophyl, which, according to 
 M. Verdeil, contains a large quantity of iron in a peculiar state of organic 
 combination analogous to the state iron is found in the haematin (red colouring 
 matter of blood). 
 
 According to Dr. G.J. Mulder, chlorophyl should contain nitrogen, but it is 
 presumable that the chlorophyl he prepared from grass was not sufficiently 
 purified, and therefore contained some protein compound. When an alcoholic 
 solution of chlorophyl is first diluted with water, and next treated with gela- 
 tinous alumina, there is formed a deep green lake, while the supernatant 
 liquid becomes yellow. This experiment has suggested to M. Fremy the idea 
 above alluded to, and the following plan of separating the supposed pigments : — 
 First, a saturated solution of hydrochloric acid in ether is made, by mixing in a 
 glass stoppered bottle 2 parts of ether and 1 part of hydrochloric acid, slightly 
 diluted with water ; the acid is made to saturate the ether by strongly shaking 
 the bottle containing the mixture : on the other hand, the chlorophyl is treated 
 with an alkali, whereby it is converted into a beautiful yellow body, soluble in 
 alcohol, ether, sulphide of carbon, and capable of forming with hydrate of 
 alumina a yellow lake, which, on being decomposed by means of an acid, gives 
 up its pigmentary matter to any of the solvents just named. 
 
 When the yellow pigment just mentioned is treated with the mixture of 
 hydrochloric acid and ether the latter fluid becomes purely yellow, while the 
 lower layer of hydrochloric acid assumes a beautifully blue tint. The expla- 
 nation of this phenomenon is given by M. Fremy in the following terms : — 
 Chlorophyl, he says, is a mixture of a blue and a yellow pigment, the blue of 
 which is temporarily bleached by alkalies, and the yellow pigment — which they 
 produce from the originally green-coloured substance— is a mixture of the 
 primitive yellow and the colourless product formed by the action of the alkalies 
 upon the cyanin. When, therefore, the yellow matter is treated with ether 
 and hydrochloric acid, the original yellow pigment of the chlorophyl is dis- 
 solved in the ether, and the cyanin, being restored to its colour by the acid, 
 becomes dissolved in the latter, forming a blue solution. This experiment 
 may be readily made, either with chlorophyl or with previously dried green 
 leaves. 
 
 The name of phylloxanthin is given by M. Fremy to the supposed original 
 yellow constituent of chlorophyl, while he calls the yellow substance resulting 
 from the temporary alteration of the blue principle (phyllocyanin) contained 
 in chlorophyl, phylloxanthein. 
 
 The regeneration of phyllocyanin by acids does not require the action of 
 air. When plants are reared in the dark, or at least nearly so, direct sunlight 
 being excluded, they contain phylloxanthin and phylloxanthein, and by the 
 
CHLOROPHYL. 
 
 437 
 
 adtion of acids the green colour is rapidly restored. The yellow leaves which 
 fall in autumn contain phylloxanthin only, and their alcoholic extract does 
 not yield — when treated with the above-named mixture of hydrochloric acid 
 and ether — the characteristic phenomenon : the cause, therefore, of the 
 autumnal change of the leaves is the fact that while the phylloxanthin — a 
 rather stable compound — remains, the phyllocyanin is oxidised and completely 
 decomposed. We mention these facts here because they give a clue to the 
 failures of chlorophyl as a dye-ware. 
 
 It may interest our readers to learn what kind of attempts have been 
 made, especially by M. Verdeil, to fix the green colouring matter of 
 plants to woven textile fibres. He extracts from the fleshy parts of the im- 
 mature flower-buds of the thistle and artichoke a green-coloured pigment, 
 apparently different from chlorophyl as well as from lo-kao. The juice 
 squeezed from the buds is originally colourless, but by the action of air and 
 the addition of carbonate of soda it assumes a greenish-yellow, which is con- 
 verted into a bluish-green after neutralising with acetic acid. The colouring 
 matter is next precipitated by acetate of lead, and the ensuing precipitate is 
 decomposed by means of sulphuric acid diluted with alcohol, and kept at a 
 temperature of 40 . The alcoholic solution becomes yellowish-brown ; the 
 sulphate of lead having been removed by filtration, the colouring matter is 
 precipitated by the addition of ether, and the precipitate, having been collected 
 on a filter, is first washed with ether and next with water. The substance 
 thus obtained is insoluble in water, ether, and acids, but soluble in alcohol 
 and alkalies, forming, with the oxides of aluminium and tin, deep green lakes, 
 which resist the action of light, and might be applied for the purposes of 
 printing on tissues, as well as for artists' colours. The green is not, however, 
 particularly beautiful. 
 
 M. Hartmann* has experimented for the purpose of applying the chlorophyl 
 of grass to woven fabrics. This chlorophyl is prepared in the following 
 manner; — The grass is first washed with warm and slightly alkaline water, 
 and then steeped for twenty-fours in a caustic soda-lye of sp. gr. 1*070, con- 
 taining about 775 percent of dry caustic soda; the deeply coloured fluid is 
 decanted, and next precipitated with hydrochloric acid, yielding a flocculent 
 green matter, which is collected upon a filter and washed. The quantity of chloro- 
 phyl thus prepared is far from abundant, being only 1 part for 100 parts of 
 grass. The pigment, suitably thickened with gum, to which lime-water or 
 ammonia is added, yields, when printed and steamed, colours which — although 
 not exactly beautiful — are fast, and prove, moreover, that chlorophyl may be 
 fixed on woven fabrics. 
 
 M. Cordillot prefers the following process: — Grass is first exhausted by boiling 
 water, and next treated with a very weak caustic soda solution (sp. gr. i , oi3), 
 which also contains some phosphates of alumina and lime ; the previously 
 decanted green liquid is neutralised with hydrochloric acid, whereby a green 
 flocculent matter — a lake of chlorophyl — is thrown down. 
 
 For the purpose of printing the author takes 250 grms. of a caustic soda 
 solution, sp. gr. i"333, containing about. 31*2 percent of dry caustic soda to 
 1 kilo, of the moist pasty lake : this solution has a specific gravity = 1-070. 
 100 kilos, of grass yield about 8 litres of the pasty lake, which, after having 
 
 * " Bulletins dc la Societe Industricllc de Mulhousc," xzvi., 283. 
 

 438 DYEING AND CALICO PRINTING. 
 
 been thickened with gum-water, is printed and steamed. The following sub- 
 stances may, if desired, be added to the lake: — Phosphate of soda, either 
 alone or mixed with past}' hydrated binoxide of tin, binarseniate of potassa, 
 alone or with the same preparation of tin. 
 
 When silk or wool is put in a bath made up of extract of chlorophyl 
 (sp. gr. 1-070), and containing phosphate[of soda and oxide of tin, very deep 
 shades are produced. 
 
 It is a well-known fact that dead wood often exhibits a green colour : such 
 wood yields, when treated with chloroform, a beautifully bluish-green matter, 
 which differs from chlorophyl by its chemical properties, and has been named 
 xylochloric acid.* 
 
 The flowers of the tree Sophora jfaponica, a native of Japan and China, 
 belonging to the Leguminosea;, yield a yellow and green pigment, the former 
 being, according to Dr. Stein, identical with the rutinic acid obtained from the 
 flower-buds of the Cnpparis spinosa, and occurring in the Ruta graveolens. 
 The yellow flowers of the tree known in China as hwae or hoai are collected 
 just before they begin to fade, sun-dried, moistened with the juice of some 
 other flowers which are pounded along with salt in a mortar, formed into the 
 shape of small balls, and next gently dried in the shade. When it is desired to 
 dye silk yellow by means of this preparation, the silk is first steeped for twelve 
 hours in a solution of alum, and next placed in a boiling decoction of the hoai. 
 MM. Michel and Guinon state that the colouring matter only exists in the 
 flowers. Alkalies redden the pigment, acids discolour it ; bichromate of 
 potassa turns the colour a bright mahogany-brown. In order to dye green 
 with this substance the Chinese make use of the action of sunlight : they im- 
 merse, according to the statement of M. Madows, the cotton in a boiling 
 alumed solution of hoai', and repeat this operation frequently. After drying 
 the cloth so treated, each time by exposure to sunlight, the late Mr. Walter 
 Crum obtained, by following this method, only a faint green. 
 
 Blue Colouring Substances. 
 
 We have already cursorily noticed some blue and bluish-violet colouring 
 matters of vegetable origin. Such blue substances, however, are practically of 
 little use : the only immediate blue vegetable principle which deserves our 
 attention is indigotin, a nitrogenous perfectly well chemically-defined prin- 
 ciple, the produce of several plants, and probably also generated under certain 
 conditions in the animal organism. 
 
 Wc shall first speak of indigotin as a chemical substance, without taking 
 into account its variable origin. We shall next describe the natural history of 
 the plants wherein indigotin is formed, and the industrial preparation of indigo, 
 its qualities and applications. 
 
 Indigotin has not been hitherto artificially produced with certainty, and the 
 relations it bears to one or other of the great series of organic chemistry are 
 only imperfectly ascertained : the elementary ultimate composition of indigotin 
 is perfectly well known, and its formula, C8H 5 NO, or any multiple thereof, is 
 thoroughly controlled by a great number of derivatives. 
 
 Indigotin may be obtained in a crystalline state by sublimation, and in that 
 case the crystals exhibit a eoppery reflection. If reduced to powder it is deep 
 
 * Forclos, " Rcpertoiie de Chimie Appliquee," v., 331, 1863. 
 
INDIGOTIN. 
 
 439 
 
 blue, and the form of the crystals is a right rhomboidal prism, terminating in 
 two strongly inclined planes. 
 
 Amorphous indigotin, as obtained by the oxidation of solutions of white 
 indigo in contact with air, is deep blue, with a purplish hue, and assumes by 
 rubbing a coppery lustre. 
 
 Indigotin volatilises at 290 , but the volatilisation is usually accompanied by 
 partial decomposition ; and only when the pure material is operated upon, and 
 the volatilisation aided by some inert gas, decomposition is prevented. 
 
 Sublimed indigotin may, according to Dumas, be readily obtained by placing 
 a thin layer of indigo in a clean frying-pan, and using another frying-pan as 
 cover, the lower pan containing the indigo being cautiously heated, preferably 
 on a sand-bath. Indigotin and indigo produce, when strewed over red-hot 
 coals, violet vapours, not unlike those arising from heated iodine, and simul- 
 taneously a peculiar aromatic odour is given off. 
 
 Indigotin is insoluble in water, alcohol, ether, fatty and essential oils, and 
 dilute acids and alkalies, either hot or cold. Creosote (Reichenbach's) and 
 phenic acid and aniline dissolve a small quantity of indigotin at a boiling 
 heat, but, on cooling, it is re-deposited. When finely pulverised indigotin is 
 mixed with anhydrous acetic acid, and a single drop of concentrated sul- 
 phuric acid is added, there is obtained a beautiful deep blue liquid, from which 
 the indigotin is separated unaltered on the addition of water. If the original 
 acetic acid solution is applied to any woven tissue, and immediately after- 
 wards washed in water, the tissue is dyed blue. It should be observed that 
 this process is the only manner hitherto known in which indigotin, without 
 being reduced, is reproduced in its primitive state. Indigotin is a thoroughly 
 neutral substance, void of taste and smell ; its sp. gr. is i"35. When decom- 
 posed by dry distillation indigotin yields, among other products, aniline. By 
 oxidising agents, such as concentrated solution of chromic acid and chlorine, 
 indigotin is converted, when water is simultaneously present, into a new sub- 
 stance, which differs from indigotin only by having one atom of oxygen more in 
 its composition, and which is named isatin. It is usually obtained from indigotin 
 by the action of moderately diluted nitric acid. Strong and hot nitric acid 
 converts indigotin into indigotic or nitrosalycilic and picric acids : in either of 
 these reactions some carbon is eliminated, in the shape of carbonic or oxalic 
 acid. The most interesting, and practically most valuable, property of indigotin 
 is its great power of fixing hydrogen, and becoming converted into a colourless 
 body, soluble in alkalies or alkaline earths, and capable of reproducing indigotin 
 by simple exposure to the oxidising action of the air. This phenomenon of 
 hydrogenisation, improperly called reduction, requires the hydrogen to be in 
 the nascent state, and it is generally considered that this reaction can only take 
 place in the presence of alkalies or alkaline earths only, but Schlumberger has 
 observed this phenomenon taking place in an acid liquid, the conversion of 
 indigotin into white indigo being quite complete. 
 
 It is well known that the freshly-prepared solution of zinc in sulphurous 
 acid decolourises energetically the solution of sulphate of indigo, as well as 
 other colouring matters. When a concentrated solution of sulphurous acid 
 is poured over granulated zinc, the liquid becomes first yellow, and rapidly 
 acquires this decolourising property, there being formed a mixture of sulphite 
 and hyposulphite of zinc : none of the substances present in this mixture 
 
44Q 
 
 DYEING AND CALICO PRINTING. 
 
 possess, by themselves alone, the property of decolourising sulphate of indigo, 
 and, moreover, this zinc solution only retains that property for a few hours. 
 M. Schcenbein* states that sulphurous acid and neutral sulphites barely act 
 upon the solution of indigo in sulphuric acid, but that acid sulphites (bisul- 
 phites) decolourise this solution very energetically; the original blue colour is 
 restored by the action of strong acids, alkalies, water in excess, lowering as 
 well as raising the temperature, and other influences. The zinc solution also 
 decolourises powdered indigotin if, simultaneously, ebullition be applied. The 
 instance is the only exception to the rule that the reduction! of indigotin 
 requires, and is effected by, the intervention of alkalies or alkaline earths, the 
 latter acting as solvents for every particle of hydrogenised or white indigo. 
 The resulting solution is a clear, transparent, golden-yellow liquid, which in 
 contact with air becomes covered with a coppery looking thin film of regene- 
 rated (re-oxidised) indigotin. 
 
 Dyers apply the term indigo-vats to solutions of reduced indigo prepared on 
 the large scale, by means which we shall presently explain. 
 
 The following substances have the power of converting indigotin (including 
 of course indigo as well) into what is termed white or hydrogenised indigo. 
 The substances and methods applied in practice on the large scale will be 
 afterwards fully explained. 
 
 i. Alkaline metals : as might be expected, these bodies — which, in contact 
 with water, yield hydrogen as well as an alkaline solution — are highly 
 reducing agents, and their mode of action is greatly regularised by 
 being made into amalgam with mercury. If sodium amalgam is 
 brought into contact with finely pulverised indigotin and water, reduc- 
 tion rapidly ensues. 
 
 2. The metals and non-metallic elements which decompose water in the 
 
 presence of an alkaline base, viz., tin, antimony, aluminium, phos- 
 phorus : these, bodies, however, only act when an alkali is present, and 
 require a higher temperature. 
 
 3. Such metallic oxides as are readily capable of higher degrees of oxidation, 
 
 as, for instance, the protoxides of iron and tin. 
 
 4. The acids which, as phosphorous and hypophosphorous, are readily per- 
 
 oxidised ; but these acids only act as reducing agents when bases are 
 present. 
 
 5. Some sulphurets, phosphurets, and arseniurets; for instance, sulphuret of 
 
 arsenic (realgar). 
 
 6. Such organic matters as are oxidisable in the presence of alkalies, as, 
 
 for instance, glucose and gallic acid. 
 
 7. Reducing and alkaline fermentation, butyric fermentation. 
 
 Sulphur and the oxides thereof, of a higher degree than sulphuric acid, not 
 only do not act as reducing agents upon indigotin, but are without any action 
 whatever, even in the presence of alkalies, and it appears, even, that — as re- 
 gards all the polysulphurets of the latter — they abstract from already-reduced 
 white indigo its combined hydrogen, and precipitate, consequently, blue 
 indigotin. 
 
 * " Poggendorff's Annalen," civ., 300. 
 
 t Although, as already stated above, this word is not precisely a correct expression for the 
 real process hereby alluded to, we preserve its use here, t.ince it is a generally accepted term. 
 
WHITE INDIGO. 
 
 441 
 
 The sulphurets which act as reducing agents — as, for instance, realgar, orpi- 
 ment, the protosulphurets of tin and antimony — exert their reducing action 
 as a consequence of their tendency to become oxidised by the influence of 
 alkalies ; the sulpharsenic and sulphantimonic acids, and bisulphide of tin, 
 are inert. 
 
 On the small scale, the hydrate of protoxide of iron and glucose are fre- 
 quently applied in chemical laboratories for the purpose of preparing indigo- 
 vats. For this purpose the following mixture answers very well : — 1 part of 
 finely ground indigo,* 2 parts of pure sulphate of protoxide of iron, 3 parts of 
 slaked lime in fine powder, and 200 parts of water : the dry substances are, 
 when ground, well mixed together, and introduced into a narrow-necked flask, 
 into which should be inserted a tightly-fitting cork ; the water (best tepid) is 
 poured in after the dry substances have been put into the vessel, which should 
 be completely filled by the liquid, and immediately afterwards closed by the cork. 
 The flask is shaken now and then, and left standing for several hours ; the yellow 
 liquid is a solution of white indigo in lime-water ; the deeper yellow precipitate 
 is a mixture of sulphate of lime and hydrated peroxide of iron. The reactions 
 which take place in this experiment may be briefly summarised thus : — A por- 
 tion of the hydrate of lime decomposes the sulphate of iron, forming hydrated 
 protoxide of iron, which begins to decompose water, immediately the nascent 
 hydrogen reacts upon the indigotin, converting it into white indigo, which in 
 its turn combines with another portion of the lime, and becomes dissolved in 
 water as a calcic compound — 
 
 2(C 8 H 5 NO) + H 2 = C l6 H I2 N 2 2 . 
 
 Indigotin. White indigo. 
 
 According to Fritzsche the glucose-vat is prepared as follows : — 125 grms. 
 of finely-powdered indigo, along with an equal weight of grape-sugar, are 
 placed in a flask of about 6 kilos, capacity, filled partly with boiling alcohol 
 at 71 per cent ; to this fluid are added 200 grms. of a concentrated alcoholic 
 solution of caustic soda, and next the flask is entirely filled with boiling 
 alcohol ; the flask, well corked, is shaken for a time, and then left standing; 
 the clear supernatant liquid, having been decanted, yields, when stirred up in 
 contact with air, a precipitate of blue indigotin, in the shape of coppery- 
 looking, small, needle-shaped crystals, these being only obtainable in the 
 humid way by the process here described. 
 
 While it is easy enough to prepare white indigo in alkaline solutions, it is 
 difficult to obtain that body in a pure and solid state, — a preparation which 
 requires great care and dexterous manipulation. White indigo is so readily 
 oxidisable, when once exposed to air, that the manipulations required for pre- 
 cipitating, washing, filtering, and drying it, cause it to be almost entirely 
 re-converted into blue indigotin, unless it is completely kept from contact 
 with air. 
 
 M. Dumas gives the following description of his process devised for pre- 
 paring white indigo : — An indigo-vat, with sulphate of iron as above described, 
 is made with 500 grms. of indigo, in a thoroughly-closed vessel suitable for 
 the purpose : after having been left standing the clear liquid is, by means of a 
 
 * Although somewhat difficult to pulverise, on account of a peculiar toughness of this sub- 
 stance, it is preferable not to purchase it in the powdered state, as it is then far more likely to be 
 adulterated. 
 

 442 
 
 DYEING AND CALICO PRINTING. 
 
 syphon, transferred to bottles previously filled with carbonic acid gas, and on 
 the bottom of which is poured also some pure hydrochloric acid freed from 
 air, in sufficient quantity to saturate the lime and precipitate the white indigo. 
 Every bottle should be completely filled, stoppered immediately, and next 
 immersed in a tub filled with water, and left standing until all the white indigo 
 is precipitated. As soon as this is the case the clear supernatant liquid is 
 withdrawn by means of a syphon, and the precipitate placed on a filter and 
 left to drain under a bell-jar filled with carbonic acid gas : the precipitate is 
 washed with cold water, freed from air by long-continued boiling, and cooled 
 in well-stoppered bottles ; the precipitate is next dried over sulphuric acid 
 under the receiver of a good air-pump. White indigo so prepared is a 
 coherent whitish-grey mass, of silky lustre, void of taste and smell, insoluble 
 in water, soluble in alcohol, ether, alkaline solutions, and lime and baryta 
 waters, forming yellow solutions. When in contact with air the white indigo 
 becomes gradually blue, through and through ; but this change takes place far 
 less slowly than when the compound is moist. Oxidising substances produce 
 the same effect, and this also applies to a comparatively slight elevation of 
 temperature, which has the effect of turning the white substance suddenly 
 blue : dry distillation decomposes this body, there being formed a small quan- 
 tity of sublimed indigotin, while a bulky charcoal is left. Strong sulphuric 
 acid dissolves white indigo, producing a deep purple liquid ; after addition of 
 water a solution of sulphindigotic acid remains. 
 
 White indigo is a very weak acid ; it dissolves in and combines with alkalies, 
 alkaline carbonates, and the alkaline earths ; but the combination is so feeble 
 that even the attraction of textile goods is sufficiently powerful to break it up, 
 and cause the precipitation of the acid on the fibre. 
 
 Many of the metallic salts yield, with the alkaline solutions of indigo, heavy, 
 white, sometimes even crystalline, precipitates, which may be considered as 
 constituting compounds of white indigo with the corresponding metallic 
 oxides. Such are the following : — Salts of magnesia, alumina, zinc, protoxide 
 of iron, cobalt, manganese, lead, silver, protoxide of tin. Salts of copper ad: 
 as energetic oxidising substances, converting the white indigo into blue 
 indigotin. 
 
 According to Berzelius white indigo forms two compounds with lime, a 
 soluble and an insoluble, the latter containing excess of lime : this fact is of 
 practical interest, inasmuch as if— in the making up the so-called copperas-vat 
 — too much lime is added, a portion of the indigo will precipitate and remain 
 inactive at the bottom of the vat. 
 
 A boiling, concentrated, caustic potassa-lye, sp. gr. 1-45, containing about 
 45 per cent of dry caustic potassa, dissolves indigo, yielding an orange solution. 
 On the addition of water the liquid becomes at first brownish-yellow, and de- 
 posits, when in contact with air, indigotin, while isatate of potassa (isatin 
 + hydrate of potassa) remains in solution. There takes place, in this 
 instance, an oxidation as well as a reduction of indigotin, according to the 
 following formula : — 
 
 3C8H 5 NO + KHO + H 2 = C8H6NK0 3 + C I 6H I2 N 2 2 . 
 
 Isatate of potassa. White indigo. 
 The oxidation of this last body gives rise to the formation of indigotin : 
 indigotin fused with caustic potassa gives off hydrogen, and is converted into 
 
INDIGOTIN. 
 
 443 
 
 anthranilic acid (C 7 H 7 N0 2 ), and if heated to 300 , along with solid caustic 
 potassa, indigotin yields salicylic acid (C 7 H60 3 ), and when submitted to dry 
 distillation along with caustic potassa, aniline (CeH 7 N) is formed. 
 
 Without entering here into lengthy details which belong strictly to the 
 domain of theoretical organic chemistry, we may observe that these reactions 
 evidently denote an intimate relation between indigotin and the phenyl 
 group ; salicylic acid, indeed, may be formed by the combination of carbonic 
 acid with phenate of soda, whereby salicylate of soda is obtained, While 
 anthranilic acid can be considered as phenyl-carbamic acid, and aniline as 
 representing phenylamin. Dry indigotin is not acted upon by either chlorine 
 or bromine, but if water is simultaneously present oxidation takes place, 
 and isatin is first formed, but entering into combination with the haloids the 
 ultimate result is the formation of substitution products, such as chlorisatin 
 and bromisatin. Iodine has no action upon indigotin, either in the dry or 
 moist state. Concentrated sulphuric acid yields, with indigotin, sulpho- 
 conjugated acids and sulphuric acid derivatives, the production of which 
 depends upon the nature of the acid (fuming or ordinary), the duration of the 
 contact, and the temperature applied. There are thus formed either sulpho- 
 purpuric acid (C I 6H I oN 2 02,S0 3 ) or sulphindigotic acid (C8H 5 NO,S0 3 ), or the 
 hyposulphindigotic acid, which is described only by Berzelius, and the com- 
 position of which is not accurately known. Sulphopurpuric acid, also known 
 as sulphophenicic acid, phenicin, and indigo-purple, is the product of the first 
 moments of the action of sulphuric acid upon indigotin, and even when the 
 contact of the acid and the indigotin is very short, especially if fuming acid 
 be employed, it is very difficult to obtain sulphopurpuric acid perfectly free 
 from sulphindigotic acid. 
 
 M. Camille Kcechlin* states, contrary to the observations of Berzelius and 
 Gerhardt, that when fuming acid is employed, though the contact of the acid 
 and indigotin be only for a few minutes before the addition of water, no 
 sulphopurpuric acid at all is obtained. He advises the use of strong common 
 sulphuric acid. This last-named acid converts indigotin readily into sulpho- 
 purpuric acid ; the best mode of preparing the latter consisting in mixing 
 finely ground indigo with the acid, so as to form a homogeneous mass, which 
 is to be poured at once into at least from fifty to sixty times its bulk of cold 
 water, in order to prevent gradual conversion into sulphindigotic acid. 
 The former acid is sparingly soluble in an acidified liquid ; it is therefore 
 deposited from the large bulk of water in the shape of a red flocculent body, 
 which is collected on a filter, and washed with water slightly acidified with 
 hydrochloric acid. This washing, however, is not sufficient to obtain the acid 
 in a pure state, for which purpose wool-yarn or worsted should be immersed 
 in a bath of it, and next washed in a solution of carbonate of soda, whereby 
 the sulphindigotic acid which might have been present is washed out, sulpho- 
 purpuric retained, and may be removed by washing in acidulated water. A 
 better method of purifying sulphopurpuric acid is to apply the unequal solu- 
 bility of the potassa or soda salts of the two conjugate acids ; the sulpho- 
 purpurate being far less soluble, it is clear that after careful neutralisation of 
 the acid mixture, previously diluted, however, to some extent with water, the 
 effect of a prolonged washing will be the elimination of the blue, while the 
 
 ' Bulletins de la Socicte Industrielle de Mulhouse," vol. xxiv., p. 33i- 
 

 flHtW 
 
 444 
 
 DYEING AND CALICO PRINTING. 
 
 purple remains, and may be employed to dye wool in an acidulated bath. 
 The aqueous solutions of sulphopurpuric acid are blue, and yield when 
 neutralised with either an alkaline carbonate or acetate a purple flocculent 
 precipitate; the ensuing alkaline salts are red in the dry state and blue in 
 aqueous solution. Their solubility in water is not very great, i part of the 
 potassa salt requiring ioo parts of water ; even very dilute solutions of sulpho- 
 purpuric acid are precipitated by the salts of lime, magnesia, alumina, 
 iron, tin, and copper. Reducing agents, such as protochloride of tin, albumen, 
 &c, bleach this acid, but its colour is restored by exposure to air. Concen- 
 trated sulphuric acid converts sulphopurpuric acid into sulphindigotic acid, 
 which latter is in its turn re-converted into sulphopurpuric acid by digestion 
 with indigo. By long-continued boiling with water the colour of sulpho- 
 purpuric acid is converted into a deep blue ; hot alkaline lyes turn it green, 
 but in the cold alkalies are without action upon it, though they cause sulph- 
 indigotic acid to become yellow. 
 
 Sulphindigotic acid, C8H 5 NO,S0 3 , is readily obtained by the action of sul- 
 phuric acid either upon indigotin or crude indigo. When ordinary concentrated 
 sulphuric acid is employed the best proportion is from 15 to 20 parts of the acid 
 to 1 of indigo ; the reaction is rendered more complete by the aid of a tem- 
 perature of 40° to 50 ; when fuming sulphuric acid (so-called Nordhausen) is 
 used the proportion of acid is from 6 to 8 parts; the blue liquid (which, if 
 fuming acid is used, inclines more to a purple) is poured into from thirty to 
 forty times its bulk of cold water; any sulphopurpuric acid present is thereby 
 thrown down, and after having been removed by filtration, there is obtained 
 a deep blue liquid, containing sulphindigotic, and a certain quantity of 
 hyposulphindigotic, acid. These acids are separated from each other, according 
 to Berzelius, by immersing white woollen worsted yarn in the liquid ; the 
 dye is attracted by the wool, which is next digested for some time with a weak 
 solution of carbonate of ammonia, whereby the coloured acids are re-dissolved. 
 This solution is evaporated to dryness at 50 on a water-bath, and the dry 
 residue exhausted with alcohol at 83 per cent strength, which dissolves the 
 hyposulphindigotate of ammonia ; the insoluble residue is taken up with 
 water, and precipitated with acetate of lead ; the sulphindigotate of lead 
 having been collected on a filter and washed, is suspended in water, and de- 
 composed by a current of sulphuretted hydrogen gas. The sulphide of lead 
 being removed by filtration, the filtrate is at first colourless, but becomes blue 
 by contact with air. On being evaporated at 50 sulphindigotic acid remains 
 behind as an amorphous deep blue, hygroscopic m.3ss ; which has an arid and 
 simultaneously astringent taste, and a pleasanTvery characteristic smell; this 
 acid is very soluble in water and alcohol. The salts of this acid are blue, 
 amorphous, and exhibit in the dry state very strongly the coppery lustre of 
 good indigo. These salts are prepared either by the direct reaction of the 
 acid and a base, or by the reaction of the acid with a carbonate or acetate, 
 while the sulphindigotates, which are insoluble, or only very slightly soluble, 
 may, of course, be prepared by double decomposition. The alkaline salts of 
 this acid are very sparingly soluble in liquids which contain neutral salts in 
 solutionis, for instance, chlorides of potassium and sodium, sulphate of soda, 
 and, consequently, the alkaline sulphindigotate is precipitated as a flocculent 
 matter when to any of its aqueous solutions a solution of any neutral salt is 
 

 SULPHINDIGOTIC ACID. 
 
 445 
 
 added. Sulphindigotate of potassa requires 140 parts of water for solution ; 
 trie soda salt is somewhat more soluble ; the baryta salt is rather sparingly- 
 soluble in cold, but more readily so in hot, water ; the lime, magnesia, and 
 alumina salt are very soluble, but the lead salt is insoluble. 
 
 All reducing agents, such as mixtures of zinc and sulphuric acid, tin-salt, 
 hydriodic and hydrosulphuric acids (at 50 ), zinc and sulphurous acid, de- 
 colourise sulphindigotic acid. The alkaline salts, which are reducing agents, 
 e.g., sulphites, also readily bleach solutions of sulphindigotates, but the blue 
 colour is restored by the action of the air. Hyposulphindigotic acid may be 
 obtained from the alcoholic solution of the ammoniacal salt by precipitating 
 with acetate of lead, and decomposition of the lead salt by sulphuretted 
 hydrogen. This acid is only distinguished by the solubility of its alkaline 
 salts in alcohol at 83 per cent ; practically this acid is of no importance. 
 
 The following is a brief summary of the results of the investigations made 
 by Berzelius and Gros-Renaud on the sulpho acids of indigo when a&ed upon 
 by alkalies and alkaline earths. These researches are indeed interesting, and 
 might, if resumed and more fully gone into, produce useful practical results, 
 since the savans just named found that these blue substances are capable of 
 yielding red, yellow, green, and violet derivatives, which dye wool and silk 
 without the aid of mordants. Hydrosulphindigotate of baryta in solution 
 becomes green when evaporated on a water-bath ; the residue, very soluble in 
 water and alcohol, yields with subacetate of lead a greyish green precipitate, 
 from which, after treatment with sulphuretted hydrogen, is obtained sulpho- 
 viridic acid, the solution of which appears green by reflected and red by 
 transparent light. 
 
 When sulphindigotate of potassa is mixed with 30 parts of lime-water, and 
 this mixture submitted to heat in a sealed tube, a purplish liquid is formed; 
 when, after opening of the tube, the excess of lime is precipitated by means of 
 carbonic acid, and the liquid, after having been filtered to remove carbonate 
 of lime, evaporated to dryness, the residue first washed with alcohol, and 
 next treated with water, there is obtained a beautiful purple liquor, which 
 yields, when precipitated with acetate of lead, a reddish-brown deposit, which, 
 after having been treated with sulphuretted hydrogen while suspended in 
 water, and after separation of the sulphuret of lead, leaves [a purple liquid, 
 from which, after evaporation to dryness, is obtained an amorphous brown 
 mass, sulphopurpuric acid. When sulphindigotate of potassa is acted upon by 
 lime-water in contact with air, the liquid becomes first red, next yellow. When 
 the lime is withdrawn from the liquid while still red by means of carbonic 
 acid, and the carbonate of lime is first filtered off, and the liquid next 
 evaporated, a brown residue is obtained, from which alcohol at 82 per cent 
 dissolves out a yellow compound. This yellow fluid yields, when precipitated 
 with acetate of lead, a yellow mass, which, on being decomposed by sul- 
 phuretted hydrogen, produces sulphide of lead, and sulphoflavic acid, a yellow 
 crystalline substance, after evaporation of its solution. The residue from the 
 treatment with alcohol just named dissolves in water, giving a red liquid, 
 precipitable by basic acetate of lead ; the resulting lead salt having again been 
 treated by sulphuretted hydrogen, yields, to absolute alcohol, after evapora- 
 tion, sulphofulvic acid, a reddish-yellow substance; while the residue after 
 treatment with absolute alcohol consists of sulphorufic acid, a red matter. 
 Both these acids are amorphou 5 and soluble in water. 
 
w 
 
 
 IBB 
 
 H 
 
 446 
 
 DYEING AND CALICO PRINTING. 
 
 M. Gros-Renaud's researches* gave in many aspects analogous results. 
 When indigo-carmine (that is to say, sulphindigotate of soda as met with in 
 trade) is suspended in water, and there is added to that mixture a caustic soda 
 lye, of sp. gr. i'333, containing about 30 per cent of dry caustic soda, there is 
 obtained a yellow liquid and a black precipitate, soluble in water, with a blue 
 colour. If to the yellow liquid strong sulphuric acid is added a few hours 
 after it (the liquid) has been prepared it becomes blue, this colouration being 
 permanent; if the acid is only added after twenty-four hours the liquid 
 becomes first green, next red, and at last violet. When the yellow-coloured 
 liquid is strongly acidified forty-eight hours after having been prepared it 
 becomes rapidly red after having passed through a variety of intermediate 
 hues. This red liquid dyes, if previously incompletely saturated with car- 
 bonate of soda, unmordanted wool, imparting to it tints varying from rose to 
 deep amaranth-red, according to the concentration of the liquid and the length 
 of the immersion of the wool, as well as the temperature. The violet- 
 coloured liquid just before mentioned dyes wool violet. This red substance 
 differs essentially from sulphophenicic and sulphopurpuric acids, being far 
 more soluble in water, and becoming immediately yellow on the addition of 
 a small quantity of caustic soda, but being rendered violet again by the addition 
 of as much sulphuric acid as is necessary to neutralise the alkali. Acetate of 
 lead does not form with the red matter any precipitate. Wool which has 
 been dyed amaranth with this red matter yields, when treated with strong 
 sulphuric acid, a red liquid, while wool which has been dyed with sulpho- 
 purpuric acid yields, under the same conditions, a blue liquor. The pro- 
 duction of red or amaranth dyes upon wool with sulphopurpuric acid requires, 
 after dyeing, an alkaline bath, which is unnecessary for the red liquor just named. 
 When caustic soda is made to aft for three days upon a mixture of sulph- 
 indigotic and sulphopurpuric acids, and the liquid next supersaturated with 
 concentrated sulphuric acid, there results a red liquid and a yellowish brown 
 precipitate. This latter having been collefted on a filter, and more or less 
 washed, dyes deeper or lighter yellow shades, according to the more or less 
 complete washing of the precipitate. It has not been hitherto possible to 
 reproduce indigotin from its sulphuric acid derivatives, though frequent 
 attempts have been made. 
 
 When indigotin is heated up to 180 along with chloride of benzoyl the 
 former body is converted, with evolution of hydrochloric acid, into a brown 
 matter, which fuses at 108 . It is soluble in alcohol and ether, and consists 
 of a benzoic indigotin compound, C8H 4 (C 7 H 5 0)NO.t 
 
 Isatin is a coloured matter, but not a tinftorial produft, about which, how- 
 ever, since it is an immediate derivative from indigotin, and, moreover, formed 
 during some of the industrial applications of that body, viz., during the appli- 
 cation of the discharge style upon blue-dyed grounds by means of oxidising 
 substances, we give the following particulars : — Isatin is produced by the 
 aftion of oxidising agents upon indigotin, such as chlorine water, dilute nitric 
 acid, chromic acid, ferricyanide of potassium, and caustic alkalies. It is 
 best prepared by mixing 1 kilo, of finely pulverised indigo with water, so as 
 to form a thickish paste, to which, while being gently heated, there are 
 
 * " Bulletins de la Societe Industrielle de Mulhouse," vol. xxiv., p. 343. 
 t " Comptes Rendu* de l'Academie des Sciences," lvi., p. 1050. 
 
INDIGO. 
 
 447 
 
 gradually added from 600 to 700 grms. of common nitric acid. As soon as 
 the blue colour has disappeared a large quantity of water is added, the liquid 
 next boiled, and filtered while still hot. From the filtrate impure isatin 
 separates in the shape of a brown amorphous mass, which being accompanied 
 by a rather large quantity of a semi-fluid resinous matter, is, in order to elimi- 
 nate that substance, dissolved in caustic soda, and next very carefully neutralised 
 by hydrochloric acid, and immediately after filtered. By this process the 
 resin is separated, and in order to obtain isatin from the deep orange filtrate 
 it is only requisite to acidulate the liquor thoroughly, whereby the isatin is 
 separated as a crystalline deep orange-red body, sparingly soluble in cold, but 
 better in hot, water ; soluble in alcohol, ether, benzin, and consisting of 
 C8H 5 N0 2 , that is is say, indigotin plus oxygen. Isatin is converted by nascent 
 hydrogen at the ordinary temperature into isatyd, a white, very sparingly 
 soluble substance, which bears the same relation to isatin as white indigo 
 does to indigotin. When isatin and isatyd are heated together to 130 in 
 sealed tubes, along with either hydriodic acid or with biniodide of phosphorus 
 and water, they are converted into a mixture of insoluble products, viz., isato- 
 purpurin, a red substance, soluble in alcohol and ether; isatoflavin, a yellow 
 matter, insoluble in ether, but soluble in alcohol ; and, lastly, a deep green 
 substance, insoluble in alcohol and ether. These bodies are derivatives from 
 isatin by the elimination of oxygen, and may be viewed as polymers of in- 
 digotin, with more or less oxygen in their composition. The reproduction of 
 indigotin from isatin by this reaction has not been successful, not a trace even 
 of that substance being found. 
 
 Caustic potassa converts isatin into isatic acid, while chlorine forms chlor- 
 isatin and bichlorisatin, and bromine mono and bibromisatin. Isatin combines 
 with ammonia, forming, while water is simultaneously eliminated, imesatin, 
 imasatin, isamic acid, isamid, and isatimid. Sulphurous acid combines with 
 isatin, provided either potassa or ammonia be simultaneously present, yielding 
 compounds known as isatosulphites. Isatyd combines with sulphuretted 
 hydrogen to form sulphisatyd and bisulphisatyd, the sulphur taking the place 
 of a portion of the oxygen of the compound. 
 
 Accoiding to M. Laurent, the adion of caustic potassa upon isatyd produces 
 a red body, indin, which, although not fully identical with isatopurpurin, is 
 very similar to it. An alcoholic solution of caustic potassa converts indin 
 and the sulphatisyds into hydrindin, a white or light yellow body, and into 
 flavindin, a deep yellow substance. Dr. Schiitzenberger has obtained similar 
 products by the reducing action of hydriodic acid upon isatin. 
 
 The substance known as indigo is chiefly a product of vegetable origin, 
 but occurring also or formed in the lower as well as higher organised animals, 
 including man, in some rare pathological cases of production of a blue urine 
 and blue pus. Indigo has undoubtedly been known in Asia from a very remote 
 period of antiquity, since there exist in very ancient records, written in 
 the Sanskrit language, descriptions of its mode of preparation, mainly not 
 different from the methods yet in use. The ancient Greeks and Romans have 
 also been acquainted with this drug, as proved by the testimony of Pliny, 
 while the ancient Egyptians dyed linen and cotton fabrics with indigo, since 
 pieces of woven tissues dyed blue with this substance have been occasionally 
 found among the wrappings of mummies. 
 
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 WUUUUUIHWI 
 
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 44 8 
 
 DYEING AND CALICO PRINTING. 
 
 During the middle ages indigo had become almost unknown in Europe, but 
 it is quite certain that now and then some small quantities came to Italy by 
 way of Alexandria, and it was used there to some extent. The old Dutch East 
 India Company (1602) first brought indigo from India via the Cape to Europe 
 in large quantity. The introduction of this dye-ware into Europe gave rise at 
 various times to legal ordinances and acts of Parliament in England prohibiting 
 its use. It was called a " devilish drug," pernicious to the growers of woad 
 (Isatis tinctoria), and injurious to the fabrics; but, notwithstanding severe 
 opposition, as early as 1631 half a million pounds of indigo were brought in 
 one year to Amsterdam and sold at very high price. Shortly after the discovery 
 of America it was found that some parts of that country also produced plants 
 from which indigo could be obtained. 
 
 The plants which yield indigo are rather numerous, and do not all belong to 
 the same family, though none of them contain the colouring matter ready 
 formed. It owes its origin to a peculiar colourless principle, about which more 
 hereafter, and which is converted into indigotin by a process of fermentation. 
 Among the indigotin-producing plants the most important are the genus 
 Indigofcra, belonging to the natural order of the LeguminosecE. The following 
 are the names of the more important plants cultivated for its production : — 
 Indigofera tinctoria, Indigofcra disperma, Indigofera anil, Indigo/era argentea. 
 The following are less frequently planted, or, at any rate, less valuable : — 
 Indigofera pseudotinctoria, hirsuta, sericea, cytisoides, trifoliata. 
 
 These plants are natives of Guzerat, but have been cultivated from time 
 immemorial in the rest of Hindostan, especially Bengal, Java, the Philippine 
 Islands, and also in China, though there to a far more limited extent. The 
 Spaniards brought some of these plants over and acclimatised them in several 
 parts of their former extensive South American possessions. The roots of 
 the Indigoferas are very fully developed, and the plant exhales, especially 
 towards night time, a strong and somewhat disagreeable odour. The taste 
 of the leaves is disagreeable, and they putrefy rapidly when immersed in 
 water. The experience of the indigo planters in Java is that the natives who 
 work in the fa&ories and handle the plant in various ways are liable to suffer 
 from sexual impotence, accompanied by a temporary semi-lameness of the 
 lower limbs. The exhalations emanating from indigo fields where the plants 
 are grown produce headache and nausea to those not accustomed to the 
 smell. Indigo is used internally as a therapeutic agent of some repute against 
 cataleptic and other fits. 
 
 The indigo plants are grown in India from seed sown in a loamy soil, pre- 
 viously thoroughly well ploughed and dressed. The sowing seasons are in 
 the spring and autumn, according to the special kind of the plant, the nature 
 of the soil, the situation of the field in reference to water supply, because on 
 low lying lands subject to inundations the crops must be gathered before the 
 rivers are swollen by rain. As soon as the young plants are sufficiently 
 forward they are re-planted in regular parallel rows, care being taken to weed 
 out from the soil any useless parasitic plants. The flower buds are pulled off 
 before they are fully developed, experience having taught that by so doing the 
 leaves of the shrub become larger and yield more indigo, the colourable 
 matter which produces that substance being chiefly present in the leaves. In 
 some localities the leaves, which have become bluish green, are pulled from 
 
INDIGO. 
 
 449 
 
 the plant and gathered, but in most cases the entire plant is cut down close to 
 the ground about the months of June or July, when the few flower buds left begin 
 to open. The roots left in the soil soon sprout again, producing a second and 
 even in some instances a third and fourth crop of the shrub, but in each case 
 the quality of the product becomes weaker both in quantity and quality. The 
 plants when cut down are collected in bundles and brought to the factory before 
 evening, so that they may be operated upon at once. 
 
 M. Kcechlin-Schwartz* has published an interesting account of the manu- 
 facture of indigo as carried on in Lower Bengal. The following is an abstract 
 of that paper: — Lower Bengal is renowned for the excellent quality of its 
 indigo, and the factories are among the best which exist as regard all arrange- 
 ments, containing niters, presses, cauldrons, and boilers ; drying rooms, large 
 water tanks, and, lastly, the very essential tanks for the extraction of the 
 leaves by means of water. These tanks are placed in two rows, containing 
 from 15 to 20 each, one row being placed higher than the other. The tanks 
 are built firmly of brickwork, lined inside with a strong cement; their shape 
 is rectangular, about 6 metres by 6*5, and from eg to i*o metre in depth ; the 
 uppermost row of tanks is placed about 0*9 metre higher than the lower 
 range. The tanks of the upper range serve for the purpose of the fermen- 
 tation of the plant. 
 
 Pure water in large and almost unlimited quantity is an absolute requisite 
 of an indigo factory, and in this respect the situation on or near the Ganges is 
 of great importance ; the water of that river is relatively very pure, and in 
 order to cause the deposition of suspended matter it is brought by conduits 
 into large ponds, and, after having become clarified, is conducted to large 
 tanks, which are on the same level with the masonry tanks just described. 
 The plant being cut down in the forenoon is delivered in neatly made-up 
 bundles at the factory in the afternoon. The bundles are placed neatly in the 
 tanks, each containing 100 thereof, and care is taken to pack them tightly, 
 while they are prevented from floating by the placing of stout pieces of timber 
 across the tank tightly wedged. It is essential that there should be left as 
 little open space as possible to ensure the proper progress of the fermentation. 
 As soon as the tanks are filled with bundles a sluice valve is opened, which 
 causes the water to run in, and so to fill them that the bundles are entirely sub- 
 merged. The process of fermentation goes on more or less slowly, according 
 to the prevailing temperature, but it lasts on an average from nine to fourteen 
 hours. The progress of the operation is considered good when a small 
 quantity of the liquid from the fermenting tanks, run off into the tanks of the 
 lower row, exhibits a straw colour; for although the quantity of the product 
 will in that case be rather less abundant, the quality will be better than if the 
 colour of the liquor be golden-yellow, and a turbidity be apparent at the same 
 time. When the liquor is run off from the fermenting tanks its colour is more 
 or less yellow ; after having been left at rest for a few moments twelve naked 
 men descend into the tanks and begin to stir the water very vigorously, 
 while at the same time the fermenting tanks are emptied, cleaned, and made 
 ready for another operation. The operation of stirring and beating the water 
 is continued for several hours, there being seventeen workpeople, viz., twelve 
 men and five women, employed to each tank. While this operation is going 
 
 " Bulletin de la Socicte Industriclle de Mulhouse," vol. xxvii'., p. 307. 
 
 2 a 
 
BjBjjfifi ffffffB Bfi M 
 
 450 
 
 DYEING AND CALICO PRINTING. 
 
 on the colour of the liquor becomes gradually pale green, and the indigo 
 becomes visible, being in a state of suspension as a flocculent matter. As 
 soon as this change is complete the workpeople leave the tanks, and, after the 
 liquid has been left at rest for a time, the supernatant water is run off gradually 
 by the opening of plugs placed from the top to near the bottom of the tanks 
 at convenient distances apart. The water flows again into the river, and 
 the precipitated indigo, in the form of a thickish semi-fluid mass, runs along a 
 spout into a well-constructed tank. This mass is next drawn up by the aid of 
 a hand-pump, and conveyed to a large cauldron, where it is boiled with the 
 view of preventing a further fermentation, which would spoil the produce by 
 turning it black. After having been left at rest for twenty hours in the 
 cauldron, of which, in a large factory, there are at least five often heated by 
 means of steam, the pasty mass is boiled again for from three to four hours, 
 and next, while yet hot, run on to a large filter, constructed in the following 
 manner: — In a large tank of masonry of 6 by 2 metres and 0-9 metre deep, 
 are placed pieces of bamboo cane, over which are spread lightly woven mats, 
 and next over these a strong piece of sail-cloth. Upon this latter remains a 
 thick deep blue, nearly black, paste ; the water collected in the tank still 
 deposits some indigo, and is therefore boiled up again the next day, and after- 
 wards filtered. The pasty and still very soft mass which remains upon the 
 sail-cloth is removed to small wooden boxes, perforated with holes, and 
 lined inside with a stout and strong cotton tissue. These boxes having been 
 filled, and a lid having been put on the top, likewise perforated, and so con- 
 structed as to fit in, not on, the boxes, care being also taken to place a piece 
 of cotton on the top, the boxes are placed under a screw-press, and pressure 
 having been gently and gradually applied, the water is squeezed out as much 
 as possible, that liquid being run again to the filter tank to collect any indigo 
 it may yet contain. The pressure having been withdrawn the boxes are 
 opened, and the contents, shaped like blocks of soap, are placed in the drying 
 room ; this is a large and high brick building, containing a series of window- 
 like openings, closed by Venetian blinds, so as to prevent the access of direct 
 sunlight ; while, moreover, there are planted outside and close to the building 
 large trees for the same purpose. The process ought to proceed very slowly ; 
 and it takes from three to five days to dry the contents of each box. Artificial 
 heat is not required, but in case of heavy rain shutters are put up outside the 
 Venetian blinds. As soon as the cakes of indigo are thoroughly dry they are 
 packed in well-made wooden boxes, the seams of which are made water-tight 
 with pitch, and are often lined with sheet ^inc or tinned sheet iron. After 
 having been packed the drug is sent to Calcutta, the chief market. Each 
 fermenting tank produces from 18 to 25 kilos, of indigo if the plant be 
 grown on alluvial soil, and from 16 to 32 kilos, if cultivated on older for- 
 mations. The quality of the former produce is, however, preferable to that 
 of the latter. The spent plant (after fermentation) is only used as manure. 
 The plants shoot out again if properly placed in the soil, but the indigo 
 they would produce would be altogether of a low quality, and not pay the 
 expense and trouble of the manufacture. 
 
 The details above quoted refer to the manufacture of indigo as carried on 
 by European planters, provided with a sufficiently large capital to defray the 
 heavy expenses of establishing works and beginning cultivation. The natives 
 

 INDIGO. 
 
 45i 
 
 carry on operations in a somewhat similar manner, but working on a small 
 scale, do not succeed so well, and the quality of their produce is inferior. 
 The average quantity of indigo annually made in the Bengal Presidency 
 amounts to about 4 millions of kilos. 
 
 M. Twist* states that in the Guzerata country the leaves of the indigo 
 shrubs are dried in the sun, and next steeped for four or five days in pure 
 water, previously poured into well-made tanks, care being taken to stir the 
 mixture occasionally. The liquid is run off from the tanks after lapse of the 
 above time ; and, after having deposited the indigo as a semi-fluid mass, the 
 supernatant clear liquid is slowly run off; and the indigo having been thrown 
 on to a coarsely-made but thick and tightly-woven woollen cloth, is left to 
 drain, and next dried in the sun. The natives of the above-named country 
 are in the habit of adding to the yet pasty mass some blue mineral, or clay. 
 
 The Chinese cut the plants in the manner above described, and treat 
 them further in the same way as already mentioned ; but they add powdered 
 slaked lime to the mass in the fermenting tanks, thereby causing a more rapid 
 deposition of the precipitate afterwards. The Chinese also dry the indigo in 
 the sun, according to some authors.! It is rather doubtful whether the state- 
 ment concerning the drying of indigo exposed to sunlight is quite correct. 
 
 M. Kcechlin-Schwartz relates what he has seen during a journey and lengthy 
 sojourn in Bengal ; and he was told that the exclusion of sunlight is absolutely 
 necessary to ensure good produce ; yet a great many authors, among them 
 those named in the foot-note below, speak of drying in the sun, which, as 
 regards Twist, is a communication made from personal inspection on the 
 spot. From private communication made to us by a Java indigo planter we 
 can reconcile these discordant statements ; the fact is, that as long as the 
 indigo is still soft and pasty, so that it can easily receive impressions from the 
 finger, it is kept in the shade, and almost in the dark, being merely exposed 
 to strong ventilation ; but as soon as the mass has become dry and sufficiently 
 solid to bear handling, it is further dried during the daytime in open air, being 
 placed upon hurdles made of bamboo, and purposely exposed to the sun, pro- 
 vided there be no danger of rain. This proceeding is also carried on in Bengal, 
 but is very frequently there done not at the factory, but at or near Calcutta, 
 and has therefore been overlooked by M. Kcechlin-Schwartz, who has also 
 forgotten to mention the care taken with regard to the boxes, as above specified, 
 in which the indigo is sent over to Europe. The fact is, that the ware is 
 packed for sea transport, chiefly at Calcutta, being sent thither from the 
 factories, when fit for handling though not quite dry, in light bamboo baskets, 
 as kindly communicated to us by Mr. J. A. Longridge, C.E., who has 
 travelled in India while on Government duty as Inspector and Reporter 
 on Railways. The process of indigo manufacture in America and the West 
 Indies is similar to that already described. In southern China, and especially 
 in Kouang-si, Kouang-toung, and Fo-kien, indigo is largely produced for home 
 consumption only. 
 
 We have now to consider the theory of this process of manufacture. The 
 following questions arise : — What are the chemical phenomena observed during 
 
 * " Descriptio Guzeratae ;" a very rare book. 
 
 t Sloane, Gaertner, Lamarck, Plagne ("Annales Maritimes," 1825). Vilmorin, " Journal 
 d'Agriculture Pratique," i., 449. Hervy, "Journal de Pharmacie," xxvi., 290. 
 
 2 G 2 
 
Mj JBflj 
 
 452 DYEING AND CALICO PRINTING. 
 
 the process of the fermentation of the plant, and under what influence and 
 from what substance present in the plant is indigo derived ? Since no 
 researches on the fresh indigo plants have yet been made, and since, more- 
 over, the different phases of the operations whereby indigo is produced on the 
 large scale have never been scientifically examined, we can therefore only 
 reason by analogy or from observation of what happens with other similar 
 plants, and give an explanation which is probably, but not necessarily, correct. 
 It has been at one time supposed that the leaves of the Indigoferce contained in- 
 digotin in the hydrogenised state, and that this substance became soluble under 
 the influence of a peculiar fermentation, while the stirring and beating of the 
 fermented liquid afterwards by promoting contact of the liquid with air caused 
 the oxidation of the white indigo. Although this explanation agrees with the 
 well-known chemical properties of indigo, it is not tenable on account of the 
 following facts : — The yellow liquid which runs off from the fermentation 
 tanks has a decidedly acid reaction (according to Dr. Croockewit, who, by 
 a lengthy residence in Java, has been frequently enabled to test this liquid), 
 and contains both acetic and lactic acids ; and we know by experience that 
 white indigo is not soluble in an acid liquid, and only dissolved by the aid of 
 alkalies or alkaline earths ; and unless we therefore admit the existence of an 
 unknown principle, capable of keeping white indigo dissolved in such a liquid 
 as that running off from the fermentation tanks until it is oxidised by the oxygen 
 of the air, the existence of the hydrogenised indigotin in the plant is not very 
 probable. Another opinion is, that indigo does not pre-exist in the leaves or 
 plant at all, but is formed during the process of fermentation which is usually 
 employed for the extraction of the drug (dye material) from the indigo/era as 
 well as from woad. 
 
 Dr. Schunck has discovered in the Isatis tinctoria* a principle very soluble 
 in water and alcohol, viz., a kind of glucoside, capable of being split up by 
 the action of dilute acids and alkalies, and even simply by evaporation of its 
 solutions into a peculiar sugar (indiglucin) and into indigotin; to this product 
 the chemist just named gives the name of indican, its formula being 
 C 2 6H 3I NOi 7 : the splitting-up of indican into indigotin and indiglucin may 
 be elucidated by — 
 
 C 26 H 3I NO I7 + 2H 2 = C 8 H5NO-l-3(C6H I o06) 
 
 Indican. Indigotin. Indiglucin. 
 
 The preparation of the indican will be referred to when we treat of woad ; 
 but it is probable indican may exist also in the Indigoferce ; and, if so, the 
 indican will become soluble in the fermentation tanks, and this body in 
 solution will be entirely split up into indigotin and indiglucin in the beating 
 tanks, a result which, under the prevailing high temperature (often 30 to 35 C), 
 will cause the further decomposition of the indiglucin, and also cause the 
 production of other brown, red, and yellow matters, which remain mixed up 
 with the indigo. During the process of beating up the liquor a large quantity 
 of carbonic acid is disengaged, and consequently a good ventilation has to be 
 kept up in the buildings wherein the tanks are placed. If the temperature of 
 the liquid is too low (the workpeople know by experience the most suitable 
 temperature) hot water is added, but is rarely needed. 
 
 Indigo is only, or at least chiefly, prepared from the real Indigoferce, although 
 
 * This dyeing material, known as woad, will be mere fully mentioned bekw. 
 

 INDIGO. 
 
 453 
 
 the following plants, which are used for blue dyeing, contain likewise indigotin, 
 viz., the woad, or pastel, Isatis iinctoria ; Polygonum tinctorium, largely cul- 
 tivated in Russia, and there applied for the manufacture of indigo ; Nerium 
 tinctorium, Asclepias tingens, Eupatorium tinctorium, Galcga tinctoria. 
 
 According to Dr. Schunck, indigo-blue is obtained from the leaves of 
 Blesia Tankcrvillice, a fad established also by the late Dr. Calvert. They 
 contain also indican, which the former chemist considers to be in every case 
 the parent substance of indigotin. Dr. Schunck did not succeed in obtaining 
 indigo-blue from the Galega tinctoria and Spilanthes tine tortus grown in the 
 open air in this country, but considers it possible that the colour might be 
 developed in a warmer climate. 
 
 Woad, or Pastel (Isatis tinctoria), is a biennial plant, belonging to the 
 CrucifcrcB. Its leaves are gathered in the month of June of the second year, 
 and are sometimes simply cleaned, and serve, after having been dried, for the 
 purpose of dyeing; more frequently, however, the leaves are converted by the 
 aid of water into a paste, which is heaped together to a height of from 
 go centimetres to i metre, and left fermenting for about a fortnight, and 
 then made up into the shape of small balls, similar in size to those sold as 
 washing blue. In some few instances the fermented mass is submitted to 
 another fermentation, which is accompanied by a disengagement of ammonia. 
 The material thus obtained is known in the trade (at least on the Continent, 
 since woad and its preparations are quite out of use in England)* as pastel ; 
 the best kind thereof is made in Provence and Languedoc ; next in value is 
 the Normandy ; while the growths of Thuringia, Bohemia, and Hungary are 
 of equal quality. Pastel is very frequently used for dyeing along with indigo, 
 and some dyers pretend that they cannot get good shades without it. Pastel 
 balls of good quality should be light, exhale a sweetish odour, have a green or 
 greenish yellow colour, and should when cut exhibit a greasy lustre, and leave 
 when rubbed on paper a greenish streak. They improve in tinctorial power 
 by being kept, so that when six or eight years old their value is nearly 
 doubled. It does not appear that indigo ever has been industrially prepared 
 either from pastel or the fresh plant, but there is no doubt that it can be 
 obtained from these substances; and before the re-introduction of indigo in 
 Europe in the 17th century woad was generally applied for dyeing a fast blue. 
 
 From the dried leaves of the same plant Dr. Schunck obtained indican by 
 the following process: — The leaves are treated with cold alcohol; to the 
 liquid thus obtained water is first added, and it is next concentrated by 
 evaporation at the ordinary temperature, aided by a current of dry air. The 
 concentrated liquid is filtered and shaken up with freshly precipitated hydrated 
 oxide of copper. The liquid is again filtered, and the filtrate treated with 
 sulphuretted hydrogen to eliminate the oxide of copper which had been 
 dissolved. It is again filtered, and the filtrate evaporated by the aid of a 
 current of air at the ordinary temperature until there remains a syrupy mass, 
 from which indican is extracted by cold alcohol. This solution deposits a 
 brown material, and on the addition of ether other foreign matters are thrown 
 down. The liquid having been filtered is evaporated, leaving indican as a light 
 brown, syrupy, bitter mass, which has an acid reaction with test-paper ; it is 
 soluble in water, alcohol, and ether, and susceptible of yielding, under the 
 influence of acids or of a ferment in the plant, indigo-blue and sugar. 
 
 * Woad, though no longer used as a dye, aids the fermentation of the indigo-vats. 
 
H3 
 
 BBSBSJ 
 
 454 
 
 DYEING AND CALICO PRINTING. 
 
 To obtain this interesting decomposition with acids, it is simply necessary 
 to heat the indican with strong sulphuric or hydrochloric acid, when the 
 indigo precipitates, while the sugar remains in solution. But indican is so 
 liable to undergo modification that, if the action of the acids be continued, 
 besides the indigo-blue an indigo-purple is formed, called by Dr. Schunck 
 Indirubin. This author's researches have a very important bearing upon the 
 manufacture of indigo, since they show that under the influence of a ferment 
 the indican is converted into sugar and white indigo; and they also explain 
 that if the manufacturer is not very careful he may experience great loss in 
 the amount of indigo obtained. Dr. Schunck has observed that indican, when 
 dissolved in water, is liable to undergo rapid modifications, and that instead of 
 yielding, in contact with acids, indigo-blue and indirubin, it gives indiretin, 
 indihumin, and other compounds of decomposition. 
 
 Indican is met with as an ordinary constituent of human urine and blood, 
 and also the blood of oxen. Its discovery in blood is due, we believe, 
 to Carter. The plant botanically known as the Isatis indigotica, in 
 China Tein-hoa, Tein-ching, is a native of that country, and is largely culti- 
 vated for the purpose of manufacturing a kind of indigo, which is sold in a 
 pasty, viscous state, since when once dry it only yields a blackish tint on 
 dyeing. It is used as a fast blue dye at Canton, Emoui, and other places. 
 The Polygonum tinctorium, a herbaceous plant of the natural order of the 
 Polygonese, is also used in China for the purpose of indigo manufacture, 
 yielding a material of good quality; but according to M. Natalis Rondot, the 
 plant, called lau in Chinese language, is not the Polygonum above mentioned, 
 but a kind of asclepiad. However this may be, the Polygonum tinctorium 
 has been acclimatised in Europe from seed obtained from China. The small 
 quantity of indigo it yields, only about I per cent on an average, was not found 
 to make the cultivation a paying business* in those parts of Europe where 
 indigo is readily obtainable. 
 
 M. E. Schwartz states that the indigo obtained from the Polygonum is not 
 so good as that obtained from India, in so far as the colouring value of the 
 former is less. The yield also of the plant varies according to its age, the 
 climate, the nature of the soil, &c. The manufacture of indigo from the 
 Polygonum is performed precisely in the same manner as is above described 
 for the preparation of indigo. 
 
 The indigo obtained by the process above described from the different 
 species of the Indigofcrce may vary considerably as regards its richness in 
 tinctorial matter, and the quality also of the latter differs sometimes con- 
 siderably. This is due to various causes, among which are the following: — 
 In the first place, too frequently, sufficient care is not taken in carrying out 
 the manufacturing process, the workmen, and even the planters, being often 
 entirely ignorant of the principles upon which the manufacture is based. 
 There are also employed different varieties of plants, gathered under atmo- 
 spheric conditions, which are not the same year by year ; while, moreover, the 
 ripeness of the plants and the nature of the soil on which they are grown are 
 of considerable importance. 
 
 The following kinds of indigo are distinguished in commerce, according to 
 
 * "Bulletin de la Societe Industrielle," vol. xi., p. 186; xii., 216; xiv., 212. "Journal de 
 Pharmacie," No. 5, May, 1840. 
 
INDIGO. 
 
 455 
 
 the countries whence they are imported : — Asiatic indigos, from Bengal, Oude, 
 Madras, Java, and Manilla. African, imported from Egypt, Mauritius, 
 Senegal. American, from Guatemala, Caraccas, Mexico, Brazil, the Antilles, 
 and South Carolina. 
 
 The Bengal, Java, and Guatemala indigos are considered the best ; these 
 varieties exhibit the following general characteristics : — Java indigo contains 
 generally the colouring matter in a very pure state, along with a minimum of 
 extractive organic matter ; but in some of the sorts of this drug the quantity 
 of indigotin is greatly decreased by the amount of siliceous matter present. 
 This indigo feels soft, and adheres strongly to the tongue if pressed against it. 
 The sp. gr. of this material is low ; its colour a pure soft blue, the inferior 
 qualities exhibiting an ash-grey hue, while the superior qualities are mag- 
 nificently violet-blue, and assume, when rubbed with the nail, a beautiful 
 coppery hue. The Java indigos, although not the very richest in indigotin, 
 are superior to all others as regards the purity and beauty of the colouring 
 matter ; they, moreover, contain no carbonate of lime, and are, also on account 
 of the very small quantity of organic matter they contain, in very high re- 
 quest for the manufacture of indigo carmine. Practical dyers complain that 
 Java indigos do not work well, their tinctorial value, i.e. the amount of wool 
 they will dye up to a given shade, being smaller than their appearance, either 
 in the lump or in solution, would lead the observer to expect. 
 
 The Java indigo is imported chiefly, but not exclusively, into Holland, and 
 is packed in very carefully-made wooden boxes, weighing when full from 20 to 
 60 kilos. ; the ware is in square or cubical cakes. 
 
 Bengal indigo is the indigo par excellence, on account of the yield, in- 
 cluding a great variety of sorts from the richest to the most common. This 
 ware comes chiefly to London in the shape of large prismatic lumps, packed in 
 wooden boxes, containing from 130 to 140 kilos. The higher qualities are a 
 deep blue violet. The paste is very homogeneous and fine grained ; it adheres 
 to the tongue, but less strongly than Java indigo. Bengal indigo is easily 
 pulverised, and exhibits also, when rubbed with the nail, a coppery hue ; it 
 contains on an average about 72 per cent of indigotin. The sp. gr. of indigo 
 is on an average, according to M. Ziurek, =0769, while that of indigotin is 
 = i'35- The brokers distinguish no fewer than forty-five different kinds of Bengal 
 indigo, among which are certain varieties which exhibit a reddish hue, due 
 to the presence of a larger quantity of a brown extractive matter, which, indeed, 
 far from acting injuriously on the dyeing operations, seem to exercise a bene- 
 ficial effect, because it appears to assist the fixing of the indigo on the tissues. 
 Dyers very generally prefer the reddish Bengal indigo, but reject the light 
 blue kind, which has a strong greyish or greenish tint, and is hard and dense, 
 containing a large amount of an inert extractive matter. Such indigo scarcely 
 adheres to the tongue, and does not, on being rubbed with the nail, assume a 
 coppery hue. There is met with among the Bengal qualities a variety which 
 is light blue, yet rather free from extractive vegetable matter, but contains a 
 large quantity of mineral impurities, and for the rest exhibits pretty much 
 the characters of the last-named sort. 
 
 The Oude and .Curomandel Indigos are generally heavy, brick-shaped 
 masses, difficult to break, approaching in tinctorial value the medium fine 
 Bengal kinds, and are further distinguished into violet and ordinary coppery- 
 looking:. 
 

 ■P 
 
 ■ 
 
 M 
 
 456 
 
 DYEING AND CALICO PRINTING. 
 
 Manilla Indigo is found in light, brick-shaped, or irregular masses ; colour 
 light blue ; fine-grained and homogeneous ; it effervesces with acids, in conse- 
 quence of containing carbonate of lime. This indigo is rarely used for dyeing* 
 being too poor, but it is largely employed for making washing-blues. It also is 
 imported in wooden boxes, generally weighing from 50 to 60 kilos. 
 
 Madras Indigo : fine blue or bluish-violet, less rich than, but equally light 
 (specifically) as, Bengal indigo, and characterised by the feature that the cakes 
 have retained the impression of the folds and texture of the cloth on which 
 it was placed while soft. The low Madras qualities have an unpleasant 
 greenish hue, and contain sometimes 50 per cent of mineral matter. The 
 boxes in which it is sent to Europe weigh on an average from 80 to 90 kilos. 
 
 Guatemala Indigo occurs in small irregularly-sized lumps, packed in serons 
 — bags or bales made of cow-hides, weighing about half as much as the 
 Bengal boxes. The Guatemala indigo is, as regards quality and variety, not 
 unlike the Bengal, but the ware is never so well sorted, and therefore generally 
 less valuable : the light blue kind is more rare amongst this indigo, and when 
 it occurs it is poorer in colouring matter than the same variety of Bengal 
 indigo. The reddish-coloured Guatemala is not well suited for dyeing, since 
 it is very poor in blue, and contains too great an excess of brown extractive 
 matter. Notwithstanding these defects the indigo in question often contains 
 excellent qualities. The distinguishing marks or brands are — Indigo Guatemala 
 flor, Sobre saliente, and Corte. 
 
 Caraccas Indigo resembles greatly the last-named kind, but is generally less 
 esteemed : it is packed in surons. 
 
 Mexican Indigo stands between the two last-named, but does not of late 
 years come into the market any large quantity. 
 
 From a paper published* by M. R. E. Meyer on a sample of indigo 
 manufactured in Cochin China, we learn the following particulars, first, as 
 regards that sample, and secondly, about some other varieties of indigo: — 
 The Cochin China growth consists of small, flattened, irregular lumps, 
 weighing from 3 to 6 grms. each. Judging by the impression left on the sur- 
 face, the paste has been pressed between linen while yet wet : the colour is a 
 pure bright blue, without any violet hue. It adheres to the tongue, exhibits a 
 coppery gloss, is very homogeneous, and its fracture does not show any foreign 
 substance. The author estimated the indigotin in this ware, and found its 
 average quantity to be 5i'85 per cent, while the estimation of this colouring 
 matter in the following sorts of indigo gave the following quantities : — Bengal, 
 ordinary deep blue, heavy substance, not adhering to the tongue, 55 : Bengal 
 deep reddish-blue, 63*5 ; Bengal, fine violet-blue, light (specifically), 68 - 25 ; 
 Bengal, superior quality, 69/5; Guatemala, very common brownish-blue, 55*25 ; 
 Guatemala, bright blue, common sort, ST75- The author was unable to obtain 
 either any of the Java or of the best Guatemala kinds. The quantity of ash 
 present in the Cochin China indigo amounts to 22-36 per cent, consisting 
 chiefly of phosphate of lime, accompanied by small quantities of carbonate of 
 lime, iron, alumina, magnesia, soda, but not even a trace of potassa; traces, 
 however, of copper and lead were found, due to the vessels employed in the 
 manufacture. The ash in Bengal indigo only amounts to 663, and in two 
 varieties of Guatemala to n - 34 and 7-28 per cent. 
 
 " Bulletin ck la Socictc Industrielle dc Mulhousc," May, 1870, p. 253. 
 
INDIGO. 
 
 457 
 
 Brazil Indigo occurs in small rectangular blocks, or irregular lumps : it is 
 firm, breaks readily, the fracture is not conchoidal ; it assumes, also, when 
 rubbed with the nail, a coppery hue, and is externally greenish-grey. 
 
 Carolina Indigo is in the shape of small lozenges, externally grey : both the 
 last-named sorts are superior in quality to the other American products. 
 
 Among the improvements Egypt owes to its last three rulers, the cultivation 
 of indigo-producing plants is not one of the smallest: the result is, that for 
 about the last twenty-five years there has been in the market an excellent 
 quality of this ware, met with in the shape of flattened cakes, of fine-grained 
 texture, very light, and coloured either pure blue or pure violet-blue : it is 
 packed in boxes. 
 
 Senegal and Mauritius Indigos are rarely seen in the market, but are, gene- 
 rally speaking, of very good quality. 
 
 Low qualities of indigo are characterised by a dirty, more or less greenish, 
 colour, a coarse and unequal texture, and great specific gravity ; they do not 
 adhere to the tongue, and do not become coppery by friction with the nail. 
 Such are never of any real use to the dyer, notwithstanding the low price at 
 which they are offered. The fact that some samples of indigo contain only 
 from 12 to 14 per cent of indigotin is of itself sufficient proof of the necessity 
 of adopting scientific investigation for the proper valuation of this ware. 
 Such indications are of immensely more value than the empirically obtained, 
 often useless, valuation and sorting of the brokers. All indigos which contain 
 a large percentage of impurities are a loss to the dyer, since these cause by 
 their presence a loss of colouring matter, which is rendered unavailable and 
 inactive. 
 
 The best kinds of indigo for use in the so-called cold-vat, for dyeing linen 
 and cotton,* are the medium good qualities of Bengal and Guatemala, and 
 especially the reddish varieties : the inferior qualities just mentioned are less 
 injurious when applied in the so-called hot-vats, used for dyeing wool ; and 
 this branch of industry consumes the inferior kinds to a large extent. For 
 the purpose of calico-printing the better qualities only of indigo are used. 
 
 The following are a few of the trade terms applied to indigo generally, 
 without reference to the country of its production : — 
 Sandy Indigo, containing much earthy matter. 
 Ribboned Indigo, exhibiting various shades of colour, running in the shape 
 
 of ribbons. 
 Spotted Indigo, the colour varying from spot to spot. 
 Burnt Indigo, when it happens that the ware, on pressure in the hand, 
 
 falls to black pieces. 
 Large Squared Indigo, when the cakes are broken up into several large 
 
 lumps. 
 Half Broken Indigo, when the cakes are broken in two only. 
 Coarse Granulated Indigo, the ware broken into comparatively small 
 
 lumps. 
 Cold Indigo, when the ware does not adhere to the tongue. 
 Fig Indigo, a very low quality, used possibly by the makers of laundry blues. 
 Since indigo is an expensive dye-material, and since its value depends not 
 only on the percentage of indigotin it contains, but also on its physical 
 
 * Cotton yarn, wc need hardly state, is dyed blue in the hot copperas bath. 
 

 pPPPH BPWWMB j^g 
 
 458 DYEING AND CALICO PRINTING. 
 
 properties, hardness, specific gravity, the quantity and nature of the foreign 
 matters it contains, either naturally present or fraudulently added, all these 
 conditions have to be studied when a sample of indigo has to be reported on, 
 and the chemical assay of the ware is preceded by a physical examination, for 
 which purpose several pieces are taken and attentively examined. First, a9 
 regards the recent fradure, it should be seen whether the different cakes con- 
 tained in a box are alike, and whether the fragments broken off from one and 
 the same lump exhibit the same hue. The porosity of the sample is examined 
 simply by applying the moist tongue to the recently fractured lump ; the 
 greater the adherence to the tongue the greater also will be the porosity of the 
 indigo. The coppery lustre of the drug is determined by rubbing it with the 
 nail, and the specific gravity is taken by the well-known method of weighing 
 with the 1000-grain bottle. By these determinations, aided by piactice, some 
 idea of the value of the ware may be obtained, and a great many dyers do not 
 apply any other tests at all ; but even the most experienced men are liable to 
 errors, and it is therefore better that the quantity of indigotin should be esti- 
 mated, but this estimation, however valuable in a sense, is also not sufficient 
 by itself. When the percentage of indigotin in two samples is the same, the 
 preference should be given to products which are light and soft, and for the 
 application to indigo-vats it is best to take the violet-red in preference to the 
 bright blue kinds. 
 
 For the quantitative estimation of indigotin many methods have been pro- 
 posed, but some of these are not sufficiently accurate, while others are too 
 cumbrous and lengthy, and hence not available when a large number of 
 samples have to be analysed simultaneously. We shall here only quote the 
 really useful methods, and those which are actually applied or capable of 
 being so. A weighed quantity of indigo is dried at ioo°, and next exhausted 
 by boiling water, weak acids and alkalies, and alcohol (indigo is soluble to 
 some extent in the latter liquid when boiling and very concentrated, but is re- 
 deposited on cooling) ; the residue left after these operations, deducting from 
 the weight thus obtained the quantity of ash as determined by the ignition of 
 a separately weighed sample, is considered to be pure indigotin. The pre- 
 sumption is that this body is insoluble in all the liquids applied, while the 
 foreign matters are withdrawn. 
 
 M. Pungh proposes the following method, which, although accurate, takes 
 too much time, and is hence impracticable where several samples have to be 
 assayed : — 30 grms. of previously dried indigo are mixed with lime and sul- 
 phate of iron (see " White Indigo ") ; the clear hquid is decanted, and the 
 sediment submitted to another reduction process. The joint liquids are 
 oxidised and precipitated by an acid ; the indigotin which is thrown down is 
 collected on counterpoised filters, washed, dried, and weighed. A certain 
 weight of woven tissue or yarn may be also dyed by this process, and the 
 quality of the indigo judged from the intensity of the colour. 
 
 M. Mittenzwei* reduces the indigo by means of an alkali and a proto-salt of 
 iron, pours on the liquid a layer of light petroleum oil, takes — by means of a 
 curved pipette — a known volume of the clear liquid, and introduces this into a 
 graduated tube containing a known measured bulk of oxygen gas standing in 
 a mercurial trough : from the quantity of gas absorbed the quantity of indigotin 
 
 * "Journal fur Praktische Chcmie," cxi., 81 . 
 
INDIGO. 
 
 459 
 
 is calculated, it being known that i grm. of this material absorbs 45 c.c. of 
 oxygen gas while being converted from white into blue indigotin. This 
 method is utterly unfit for the commercial laboratory, and still more for the 
 workshop, warehouse, or dye-works. 
 
 Another series of methods are based upon solution in sulphuric acid : for 
 this purpose, however, only the strongest fuming acid, sp. gr. 1-89 to 1-92, is 
 available; but what is then quantitatively determined is not so much indigotin 
 as the sulphindigotic acid, and this portion of the process varies in different 
 methods. Sometimes the assay is a colorimetrical estimation, the liquid, of 
 course, having been diluted to a certain invariable bulk; or a weighed quantity 
 of wool is dyed with the sulphindigotic acid. 
 
 Another group of methods for the quantitative estimation of indigotin 
 previously convertedjntojsulphindigotic acid depends upon the use of an 
 oxidising material which can be used in the shape of a titrated liquid ; for in- 
 stance, solution of chlorine, of bleaching-powder (hypochlorite of lime), 
 of bichromate and permanganate of potassa, &c. The end of the operation is 
 readily enough seen, since it coincides with the total destruction of the blue 
 colour of the substance. If the normal liquid can be preserved without 
 undergoing any change, it is only required to determine exactly the quantity 
 of indigotin converted into sulphindigotic acid which can be decolourised by 
 1 c.c. of the oxidising liquid; but it is undoubtedly better as advised by 
 M. H. Schlumberger, that whenever an assay is made, the experimenter should 
 operate upon equal quantities of pure indigotin and of the sample to be valued 
 at the same time. 
 
 Berthollet first suggested the use of chlorine: this method has been im- 
 proved upon by M. H. Schlumberger, and is executed as follows : — Weigh off 
 exactly 1 grm. of each of the samples of indigo to be tested, and previously 
 dried at 100°, and very finely pulverised ; weigh off also 1 grm. of pure indigo- 
 tin (easily obtainable, in dye and calico-printing works, from the vats, and to 
 be washed previous to use, first with acidulated water and next with pure 
 water) ; the substance is put in small porcelain capsules, and thoroughly 
 mixed with 12 grms. of strongest fuming sulphuric acid ; the capsules are 
 covered with glass plates, and kept standing for at least twenty-four hours at 
 a temperature of from 20 to 22 ; the liquid is diluted with water so as to fill 
 a litre measure : take of that fluid 59 c.c. by means of a graduated pipette, 
 pour it into a suitable glass vessel, and add next, gradually, by means of a 
 burette, a weak solution of hypochlorite of lime, at a strength of i° Baume 
 (sp. gr. 1-007), m quantities of about 2*5 c.c. at a time ; cease adding as soon 
 as the blue colour is entirely destroyed : in order to estimate the excess of 
 chlorine which may have been used, there is added, drop by drop, from a 
 burette, a solution of sulphindigotic acid : the same solution, as above men- 
 tioned, may do, until a yellow-greenish hue reappears. Suppose that 5 c.c. of 
 the bleaching-powder solution have sufficed to decolourise exactly 59 c.c. of sul- 
 phate of indigo (viz., 50 c.c. primitively taken, and 9 c.c. added to restore the 
 greenish-yellow colour). It is, however, advisable not to rely upon one expe- 
 riment, but to repeat it to judge more correctly. Suppose, further, that 46 c.c. 
 of the indigotin taken — treated, of course, as has been mentioned for the 
 indigo — is also equal to 5 c.c. of the chlorine solution, then the following 
 simple proportion will serve to calculate the results : — 46 c.c. of sulphuric 
 
^m um mmb www 
 
 460 
 
 DYEING AND CALICO PRINTING. 
 
 indigotin = 59 c.c. of sulphuric indigo ; 59 c.c. contain therefore 0*046 grm. 
 of indigotin ; how much is contained in 1000 c.c. ? or how many times x is 
 contained in 1 grm. of x = $5 = the weight of indigotin contained in 1 grm. 
 of indigo. This process is deficient in the following particulars : — The solution 
 of bleaching-powder changes, and therefore has to be tested afresh, and its 
 value in relation to indigotin estimated whenever a new series of experiments 
 is commenced — say at one or two days interval ; it is also impossible to guard 
 completely against loss of chlorine at the moment of mixing the hypochlorite 
 solution with the acid indigo or indigotin solution. In consequence of these 
 defects this process has been improved upon by substituting for the use of 
 chlorine other more manageable oxidating matters, as, for instance, perman- 
 ganate of potassa, by itself; a mixture of chlorate of potassa and hydrochloric 
 acid ; and bichromate of potassa mixed with the last-named acid, as proposed 
 and carried out by the late Dr. Penny. This method has met with general 
 approbation, especially at the hands of the Mulhouse and other Alsatian 
 manufacturers, who unanimously speak in favour of this process, based upon 
 the following facts : — When very finely pulverised indigo is acted upon by very 
 strong fuming sulphuric acid, the foreign organic matters it contains are car- 
 bonised, and remain behind upon the filter, after the addition of water, while 
 the indigotin becomes soluble ; when to this solution first hydrochloric acid is 
 added, and next to the previously thoroughly warmed fluid bichromate of 
 potassa, the sulphindigotic acid is decomposed and converted into sulphisatic 
 acid. When, therefore, a titrated solution of bichromate of potassa is em- 
 ployed, it is plain that the amount of indigotin may be calculated from the 
 volume of the bichromate solution used to destroy the blue colour. 
 
 It has been found, by experience, that in order to bleach a given weight of 
 indigotin, in the shape of sulphindigotic acid, the quantity of bichromate re- 
 quired is precisely that which is necessary to convert the indigotin into 
 sulphisatic acid : the reaction is very precise, and as long as any indigotin 
 remains the bichromate only attacks it: 3 molecules or 393 parts of indigotin 
 require 1 molecule or 297*2 parts of bichromate, or, percentically, 100 parts of 
 indigotin require 75*6 parts of bichromate. This process is executed in the 
 following manner : — The sulphuric acid solution of indigo is made with 1 grm. 
 of that substance, and further proceeded with as above stated in Schlumberger's 
 method; the titrated bichromate solution is to contain 7-66 grms. of the pure 
 salt to the litre : 1 c.c. of this liquid corresponds to 10 c.c. of a solution of 
 1 grm. of pure indigotin to the litre, equal to o*oi grm. of indigotin, so that 
 every c.c. of this fluid is equal to 1 centigrm. of indigotin. Take 100 c.c. of 
 the diluted solution of indigo in sulphuric acid, boil it gently in a porcelain 
 basin, add 10 c.c. of hydrochloric acid, and add next with the burette the bi- 
 chromate solution, taking care to cease adding the very moment the greenish 
 hue disappears and makes place for the orange -yellow colour. M. Meyer, in 
 the paper above quoted, while testing by this method the various kinds of 
 indigo, found that the end of the operation is not so readily seen as is gene- 
 rally stated, because the colour of the sulphisatic acid is rather more a deep 
 yellowish-brown than orange-yellow ; the original colour of the indigo solution 
 being deep blue, the disappearance of that colouration is, according to him, 
 somewhat obscured from view. It is, at all events, always desirable to make 
 two, if not three, estimations of the same sample: the number of tenths of 
 cubic centimetres of the chromic solution consumed gives directly the 
 
INDIGO. 
 
 461 
 
 percentage of indigotin contained in the indigo under examination. In order 
 to obtain reliable results by this method it is, in the first place, necessary to 
 take a fair average sample of the indigo, by breaking off lumps from a number 
 of the cakes or squares contained in a chest ; the next point to be attended to 
 is the pulverising of this substance so as to be really an impalpable powder, 
 to be sifted through a very fine silk-gauze sieve, every morsel passing through 
 the sieve. After the indigo has been acted upon by the fuming sulphuric acid, 
 and this fluid has been diluted with water, that solution must be carefully 
 filtered, in order thereby to remove the brown-coloured particles of extractive 
 matter which float about, and which, by their presence, might give rise to 
 errors of more than 15 per cent in the estimation of the indigotin, especially 
 for the lower sorts of indigo. When the indigo is dissolved in the fuming sul- 
 phuric acid,|it may happen that sulphurous acid is given off;* this is sometimes 
 present in the fuming acid itself, but it is completely removed before water is 
 added : if, however, the indigo happens to contain iron in the state of per- 
 oxide, that body would, by the action of the sulphurous acid, be reduced to 
 protoxide, and would of course in that case vitiate the action of the bichromate 
 by taking up some of that for its own oxidation. In case, therefore, indigo 
 contains peroxide of iron, it is necessary to treat it, previous to estimating the 
 indigotin, with boiling dilute hydrochloric acid — a precaution also required 
 when the indigo contains a large amount of carbonate or other salt of lime. 
 
 Indigo as met with in commerce rarely, if ever, contains so much iron as to 
 make the use of hydrochloric acid necessary, but it sometimes happens that 
 in dye-works indigo residues from the vats have to be analysed which contain 
 a large proportion of iron, and in that case the treatment with hydrochloric 
 acid becomes necessary. 
 
 Some chemists propose to dissolve the indigo in flasks, aiding the admixture 
 of the ware with the acid by the addition of some few grains of lead shot ; 
 but by adopting this method the escape of the sulphurous acid gas is prevented, 
 and it is preferable to conduct the operation in porcelain capsules or basins. 
 
 M. H. Schlumberger has published! a comparative review, in tabulated 
 form, of the value of different kinds cf indigo : the highest proportion of 
 indigotin was found by him in a superfine purplish-coloured Java indigo, at 
 96 per cent, a figure which M. E. Schlumberger considers by far too high : the 
 researches on this subject of Dr. G.J. Mulder, who has been for nearly forty 
 years the analytical chemist and scientific referee to the Dutch Society of 
 Trade and the Dutch Indian Department, prove that occasionally a few samples 
 of indigo, some few boxes, have been sent from Java containing indigo of 
 great purity, but the average varies from 16 to 82 per cent for different 
 qualities, and the superior is a rare article, not daily met with. M. E. Schlum- 
 berger states that by using the bichromate process, and testing by it various 
 kinds of indigo, he found that the quantity of indigotin averaged from 12 to 
 72 per cent. 
 
 * The production of sulphurous acid by the action of the sulphuric acid upon the impurities 
 of the indigo is a very grave objection to the use of all decolourising methods. The errors 
 thus produced are considerable, and become greater the lower the quality of the sample. 
 Dr. Schunck — certainly no mean authority — considers that no rapid and trustworthy means of 
 determining the amount of indigo-blue in commercial samples is known. 
 
 + " Bulletin de la Societe Industrielle de Mulhouse," xv., 277. 
 

 ESS 
 
 IHHh 
 
 SSBEBBERSE 
 
 462 
 
 DYEING AND CALICO PRINTING. 
 
 The impurities which are found in indigo along with indigotin are either 
 natural or have been artificially added. Among the first-named we find — 
 i- Water of hydration, which varies on an average in quantity from 3 to 
 6 per cent, and is readily estimated by drying at ioo°. 
 
 2. Various saline matters ; among them phosphates and carbonates of lime 
 
 and magnesia, sulphate and chloride of potassium ; also silica, oxide of 
 iron, in variable quantity : the lime salts are, however, the principal 
 constituents of the ash, and are present in quantities varying from 3 to 
 7, and even 20, per cent. The quantitative determination of the ash of 
 indigo is best executed by the careful incineration of about 5 grms. of 
 the sample placed in a platinum crucible : the residue, after ignition, 
 may — of course after having been weighed — be analysed or tested quali- 
 tatively, as suits the operator's objed, 
 
 3. Indigo contains some brown and red organic matters, insoluble in water, 
 
 but soluble in other liquids, among which are boiling acetic acid, boiling 
 alcohol, ether, and caustic alkalies: these organic substances more or 
 less modify the dyeing operation executed in the vat, and affect the blue 
 colour imparted to a greater or less extent: if, for instance, the red 
 colouring matter predominates, that substance becomes reduced, in the 
 same manner as indigotin, by the action of the alkali, and in the dyeing 
 process becomes precipitated upon the fabric along with the last-named 
 principle, and causes thereby a purplish colour different from that pro- 
 duced by pure indigotin : even if this latter substance is prepared in 
 the crystalline state by the glucose vat process, and therefore apparently 
 quite pure, it yet frequently yields, when treated with boiling acetic 
 acid, a certain quantity of red matter, which appears to belong to the 
 same class of bodies as isatopurpurin, one of the products of the 
 reduction of isatin by hydriodic acid. 
 We may here mention that indigo-blue has been artificially prepared by 
 Emmerling and Engler (" Berichte der Chemischen Gesellschaft zu Berlin," 
 No. 17, 1870), and that it has been obtained by Dr. Schunck by the action of 
 strong acids upon normal healthy urine. 
 
 According to Berzelius, indigo contains gluten, soluble in dilute acids. The 
 substances which are added to indigo for the purpose of adulteration are rather 
 numerous, and vary in kind with the more or less refined knowledge of the 
 persons who commit this fraud, either wilfully or from sheer ignorance, being 
 induced to believe that some foreign substances promote the action of fer- 
 
 precipitation of the i: 
 
 sing prepared as above 
 
 meruauuii 
 
 described. Among the adulterants are starch, resins, logwood and its extract, 
 Prussian blue, earths artificially blue-coloured, and it is said sometimes, 
 though rarely, German ultramarine : the detection of these bodies offers no 
 difficulty when the operator bears in mind what are the natural constituents 
 of indigo, as above laid down : — Starch is converted into sugar by boiling with 
 a dilute acid ; resin is soluble in alcohol ; logwood dissolves in water, giving 
 rise to a solution which turns red on the addition of oxalic acid, and yields a 
 blue precipitate with aluminate of soda ; Prussian blue gives, on being treated 
 with an alkaline solution, ferrocyanide of potassium ; mineral substances can 
 be recognised after incineration, and if any ultramarine is present this will be 
 readily detected by becoming decomposed by dilute mineral acids, with escape 
 of sulphuretted hydrogen. 
 
INDIGO. 
 
 463 
 
 Industrially-Prepared Sulphuric Acid Derivatives of Indigo; Indigo 
 Carmine ; Purple-Blue, also known as Boiley Blue. 
 
 For the purposes of dyeing and printing woollen and silk fabrics and yarns, 
 and likewise for the purpose of imparting a blue hue to white cottons, indigo 
 is frequently dissolved in sulphuric acid, whereby blue soluble compounds are 
 obtained which exhibit a shade different from that of indigo, and are more 
 readily applicable in dyeing. About thirty or forty years ago the solution of 
 indigo in sulphuric acid was only known and used after having been properly 
 diluted with water, being technically designated Saxon blue, or " chemic." It 
 is clear, however, that this liquid, besides being very acid, contains also the 
 brown and resinous matters present in native indigo. The preparation, more- 
 over, of this solution was subjedl to variation, since in almost every dye-works 
 the respective proportions of acid and indigo differed, while some manufacturers 
 used ordinary strong sulphuric acid only, others again fuming acid, and some 
 a mixture of both ; it accordingly depended entirely on the doses of acid and 
 indigo, the duration of contact, and the temperature, whether sulphindigotic, 
 sulphophenicic acid, or a mixture of the two, was obtained ; and since the 
 shade produced by these acids is not the same, it is clear that, according to 
 the tint preferred by the different makers, the choice of the prescription for 
 making the dye-material differed also. 
 
 M. Persoz* advises the following receipt for preparing the above solution : — 
 1 kilo, each of finely ground indigo and fuming and of ordinary, but strong, 
 sulphuric acid ; leave the mixture standing for forty-eight hours, and next heat 
 on a water-bath until a drop of the fluid, taken out by means of a glass rod, 
 dissolves in water without producing a precipitate ; after the mixture 
 has cooled, it is diluted with water so as to form a fluid of i - i34 sp. g r - > 
 18 Baume. M. Haussmann used 65 parts of fuming sulphuric acid for 1 part 
 of indigo. 
 
 Another mode of preparation is to add gradually, and by small quantities at 
 a time, 1 part of pulverised indigo to 5 or 6 parts of very concentrated fuming 
 acid, or from 10 to 12 parts of ordinary concentrated sulphuric acid : this 
 mixture is left standing for twenty-four to forty-eight hours, and is next poured 
 into twenty times its bulk of cold water, and filtered. 
 
 There is a very great difference, not to say discrepancy, between the different 
 receipts for dissolving indigo, in respedt of the proportion of indigo and acid 
 prescribed to be used. According to Dr. G. J. Mulder, who investigated the 
 cause of this difference, it is chiefly due to the fadt that various kinds of indigo 
 and the produces of various countries do not behave alike in this respect ; the 
 superior sorts of the drug are less easily a<fted upon, and, as is also ob- 
 served by M. Meyer, a really good and ready solution can only be obtained, in 
 a comparatively short time, by the use of very strong fuming acid, and even 
 then heat is required for the richer kinds : with inferior kinds the action of the 
 acid is often weakened by the presence of lime compounds, but, if these are 
 first removed by boiling with weak hydrochloric acid, the adtion of fuming 
 sulphuric acid dissolves these inferior kinds rapidly, and with less expenditure. 
 
 M. Mamas recommends to withdraw colour from the dilute acid solution by 
 means of woollen or worsted yarn. This fibre, having taken up the colouring 
 
 * " Impression des Tissus," vol. i. r p. 454. 
 
■ 
 
 MHBBHBMU BRAnMUMB 
 
 
 BWWWWW 
 
 BBS 
 
 ■PHHH 
 
 464 
 
 DYEING AND CALICO PRINTING. 
 
 matter, is first washed with water, and next with a weak alkali, which re- 
 dissolves the blue pigment, and the resulting solution is applied for dyeing 
 purposes. At present, however, the dyeing of the so-called Saxon blue is 
 effected by means of a preparation which has received a series of names ; 
 among them the following: — Indigo carmine, soluble indigo, cerulein, ceruleo- 
 sulphate, precipitated indigo, extract of indigo. The manufacture of this 
 preparation, which is in reality either a sulphindigotate or a sulphopurpurate 
 of an alkali (chiefly, if not exclusively, soda), is based upon the almost absolute 
 insolubility of alkaline sulphindigotates in any aqueous saline solution. In 
 order to illustrate the mode of formation of the preparation in question, let us 
 suppose that 1 part by weight of indigo is dissolved in from 4 to 6 parts by 
 weight of the strongest fuming sulphuric acid, and that the resulting liquid is 
 diluted with from sixty to eighty times its weight of water ; this liquid will 
 contain, beside sulphindigotic acid, an excess of sulphuric acid : when, there- 
 fore, there are gradually added to the liquid crystals of carbonate of soda, so 
 as to neutralise all the acid (which requires in this instance from n to 
 11-5 parts of the carbonate), there will be found not only sulphindigotate of 
 soda, but also sulphate of soda, and by the presence of that salt the sulphin- 
 digotate of soda is precipitated as a deep blue flocculent matter. This mate- 
 rial is collefted on a filter, and more or less washed to remove the sulphate of 
 soda, and sold as a paste, which, when dry, assumes a coppery hue, and this 
 the more strongly so the richer it is in sulphophenicic acid. It often happens 
 that these pastes contain an impurity, a dirty green matter, which can become 
 fixed upon wool and silk. This impurity, which impairs the colour of the 
 indigo carmine, may be detected by exhausting an acidulated aqueous solution 
 of the carmine with wool, previously mordanted with alum and cream of 
 tartar, because the green matter will be left in the solution. Another plan for 
 detecting this impurity is to place a small heap of the indigo-carmine paste 
 upon a sheet of white filtering-paper, when, after the lapse of some hours, the 
 circumference of the heap will exhibit a green-coloured margin. 
 
 The preparation is commercially sold in different qualities, according to its 
 richness in colouring matter. The simple extract contains, on an average, 
 4-96 per cent of indigo, 89 per cent of water, and 57 per cent of saline matter. 
 Double extract contains, in 100 parts — Indigo, 10-2; water, 85; saline 
 matter, 4-8. Triple extract— Indigo, 12-4; water, 737; salts, 13-9. While 
 becoming dry the pasty carmine is covered with a saline efflorescence, which, 
 according to M. Pohl, is prevented by mixing from 3 to 4 per cent of glycerine 
 with the paste. The thoroughly dried, at least air dry, paste is commercially 
 known as indigotin, and exhibits a blue colour : such a substance is prepared, 
 according to Mr. Watson's method, by pouring the liquid resulting from the 
 solution of 1 part of indigo with 6 parts of sulphuric acid upon 2 parts of 
 chloride of sodium. The mixture is heated, by means of steam, until no more 
 hydrochloric acid gas escapes ; there is thus formed a dry residue suitable for 
 dyeing and printing purposes ; instead of common salt, caustic potassa, car- 
 bonate of soda, or also magnesia, may be applied. 
 
 The purple-blue of MM. E. and L. Boiley is a peculiar solid extract, pre- 
 pared in the following manner:— From 10 to 20 parts of dry bisulphate of soda 
 are fused in a cast-iron vessel, and when in full fusion there is added, by small 
 quantities at a time, 1 part of indigo ; the mass swells up and appears to boil ; 
 
INDIGO. 
 
 4^5 
 
 the application of heat is continued until a small quantity taken out and put 
 in water dissolves completely, with a violet colour. The product of this re- 
 action is then dissolved in from seventy to eighty times its weight of water, to 
 which are next added 2 parts of common salt for every 1 part of the mixture 
 of indigo and bisulphate ; the precipitate thus produced is washed with water 
 containing salt in solution, and next dried. 
 
 Indigo may also be converted into indigo carmine by mixing it with anhy- 
 drous sulphuric acid (the solid substance), dissolving the mixture in water, 
 neutralising with carbonate of soda, and precipitating with chloride of 
 sodium. 
 
 The Boiley blue is a crystalline, light purplish mass, yielding, when dis- 
 solved in water, a beautiful blue-violet solution : it is soluble in concentrated 
 boiling acetic acid, depositing, on cooling, large prismatic coppery-hued 
 crystals ; it is insoluble in alcohol and ether ; soluble in water, but more 
 readily in hot than in cold : this solution is red when viewed by transmitted 
 light. The substance in question is probably chiefly composed of sulpho- 
 purpurate of soda, and is remarkable on account of its ready crystallisation : 
 its chemical properties, however, in many respects resemble those of the sul- 
 phuric acid compounds above named. It yields, with the chlorides of barium 
 and strontium, violet precipitates. 
 
 The tinctorial value of indigo-carmine can be ascertained by a dyeing 
 process, viz., a piece of woollen tissue is taken, and placed in an acidulated 
 solution of the carmine to which cream of tartar has been added. 
 
 The following are the principal sulphuric preparations of indigo used at 
 present in dyeing and printing : — 
 
 " Chemic," " chemic-blue," or " sour extract," is the solution of indigo in 
 sulphuric acid, without any neutralisation or subsequent treatment. The 
 following receipt may be used for its manufacture : — Take 1 lb. refined indigo, 
 perfectly dry and in very fine powder, and stir it gradually into 15 lbs. of the 
 strongest sulphuric acid. Let the mixture stand for three days, at a tempera- 
 ture of from 120 to 140 8 F. On dilution with water no sediment should 
 appear. Some makers vary the quantity of acid, using only 12, 10, or 9 lbs. 
 per lb. of indigo. Sometimes the acid solution is diluted with water to such 
 an extent that it can be filtered through flannel, and is afterwards re-concen- 
 trated. If unrefined indigo is used the quality is inferior, as there is no means 
 of getting rid of the brown and green colouring matters. 
 
 The paste, or " sweet " extract, varies very much in its degree of acidity. 
 The following are formulas for its preparation, beginning with the most acid : 
 — Stir 1 lb. of indigo, dry and in fine powder, — conditions which are imperative 
 in all cases, — into 5 lbs. of sulphuric acid. The mixture is kept for ten to 
 twelve hours at a temperature of ioo° F. It is diluted with 4 gallons of hot 
 water, filtered through flannel, and washed with hot water till the liquid runs 
 through nearly colourless. The liquid is then concentrated to 3 gallons, 
 4 lbs. of common salt are added, and the mass thrown upon a filter to drain. 
 The filter consists of a stout wooden frame, about 3 feet square, supported on 
 a stand, either fixed or movable. No iron must be used in the construction of 
 the frame. It is "dressed," as it is technically called, with a stout, compact, 
 white woollen cloth. Over this is placed a layer of stout fine canvas, and 
 
 2 H 
 

 466 DYEING AND CALICO PRINTING. 
 
 over this again fine calico. This triple filter is held in its place by ribs of 
 wood pegged down to the frame. 
 
 Another mixture is — 10 lbs. indigo ; stirred into 80 lbs. sulphuric acid, as 
 before. Care is taken that the heat does not rise too high during mixing. 
 Allow the whole to stand for twenty-four hours, at the temperature of 8o° F. ; 
 then add 5 gallons of water, and mix well. Next dissolve 80 lbs. common 
 salt in the smallest possible quantity of water, and add it to the indigo 
 solution. The whole is then thrown upon the filter and allowed to drain. 
 
 The following receipt is given for a " sweet " extradt of the first quality: — 
 Take 4 lbs. of the best indigo, dry, well ground and sifted through a lawn or 
 silk sieve. Add to it by degrees 37 lbs. of the best sulphuric acid, stirring 
 well, and not allowing the heat to become too strong. Let the mixture stand 
 at about 6o° to 70 F. for eight days. Next dissolve 40 lbs. of clean common 
 salt in water, and pour the solution into the acid. Then dissolve 60 lbs. of 
 soda crystals in water, and add it gradually, lest the mixture should froth 
 over. 2 lbs. of precipitated chalk are next added : the whole thoroughly 
 stirred up, thrown upon the filter, and allowed to drain. The liquid that 
 drains through the filter will be green : if its shade continues very deep, it is 
 well to wash the paste on the filter with a weak solution of salt till the 
 drainings become nearly colourless. The yield from the proportions given 
 should be 120 lbs. 
 
 It will be observed that in this formula the indigo is not added to the acid, 
 but the acid to the indigo, which, it is maintained, produces a richer and purer 
 colour. 
 
 For a second quality, 8 lbs. of indigo are treated with 74 lbs. sulphuric acid, 
 144 lbs. of salt, 112 lbs. of soda crystals, and 4 lbs. of chalk, working in the 
 same manner. 
 
 For a red extract of indigo, consisting chiefly of sulpho-purpuric acid, and 
 resembling Boiley's purple-blue, take 1 lb. indigo, 3J lbs. sulphuric acid, and 
 leave them in contact, after incorporation for twenty minutes only. Then 
 throw the solution into a very large excess of water, and wash with water 
 containing a little hydrochloric acid. 
 
 Extract in which the acid is entirely neutralised is called " free extract," 
 " soluble indigo," and frequently, though improperly, "indigo-carmine." They 
 are in the form of a dry powder. Some good authorities maintain that car- 
 bonate of magnesia is preferable to soda for neutralising extracts. 
 
 All these acid preparations of indigo should be perfectly free from undis- 
 solved particles, which, if present; are v«ry liable to render the goods spotty 
 in the dyeing process. 
 
 The paste extracts should form a rather consistent mass, of a purple colour, 
 without any green or brown reflection. 
 
 Extracts of indigo are sometimes adulterated with farina and other inert 
 matters. This fraud may be detected by dyeing comparative swatches with 
 the suspe&ed sample against an extradt of known purity. 
 
 The more acid varieties of extracts are applied on wool and worsted, whilst 
 the more neutral are reserved for silk and cotton goods. 
 
 The material commercially known as refined indigo may be obtained by two 
 different processes : — The one consists in treating common indigo, in fine 
 powder, several times with strong hydrochloric acid not containing free 
 
INDIGO. 
 
 467 
 
 chlorine : a gentle heat is applied, whereby not only the iron and lime and 
 other mineral substances are dissolved, but the amylaceous matters present 
 are converted into dextrin or sugar, which is removed by subsequent washing. 
 The indigo is next treated with a weak solution of caustic soda, which 
 dissolves the chlorophyll and other organic impurities. A still purer quality 
 of indigotin (refined indigo of commerce) may be obtained by adding to a large 
 quantity of water 1 part of finely-ground indigo, 2 parts of sulphate of 
 protoxide of iron (green copperas), and a quantity of caustic soda slightly in 
 excess of that necessary to neutralise the sulphuric acid of the copperas. 
 The mixture is boiled and allowed to settle, when the supernatant liquor is 
 run off from the sediment and well agitated, in order to convert the white 
 soluble indigo into the blue insoluble form, which is collected and dried. The 
 insoluble sediment is treated several times with a weak solution of caustic 
 alkali, in order to remove the whole of the indigotin which it contains. 
 
 In order that indigo may be used for the purposes of dyeing, printing, and for 
 the preparation of extracts, &c, the ware has always to be pulverised in the first 
 place, and this pulverisation must be so effected as to produce an almost im- 
 palpable powder. If this is neglected, a loss of colouring matter is the result. 
 Very frequently this dye ware is ground in a wet state, whereby the loss 
 ensuing by the flying off of dust is prevented ; but where the indigo is 
 required for conversion into extract the addition of water is inadmissible. In 
 almost all other cases the indigo is first steeped in water for some time, in 
 order to soften it, as in its ordinary state it is a peculiarly tough, and even 
 somewhat fibrous, substance. It is put in a suitable tub or trough, hot water 
 is poured over it sufficient to cover it, and the tub is then closed with a lid 
 and left standing for a day or two, until the water has been absorbed and 
 penetrated into the entire mass ; 10 kilos, of indigo require 15 litres of water. 
 
 In this country indigo is frequently pulverised on the large scale by dry- 
 salters, but in many cases dyers prefer to carry out this operation at their own 
 works. Among the various simple apparatus in use for that purpose we 
 mention briefly the following, which consists of a nearly hemispheric copper 
 vessel, of 07 metre diameter, and furnished at its upper rim with two handles. 
 The operator puts this vessel on a wooden bench, and seats himself thereon 
 crosswise ; he next puts three large cannon-balls, 12- to 18-pounders, into the 
 vessel, and also a quantity of previously softened indigo and some water: by 
 means of the handles a circular oscillatory motion is imparted to the vessel, 
 and the balls, partaking that movement, reduce the indigo to the state of an 
 impalpable pulp : after a certain time the liquid, containing finely divided 
 indigo in a state of suspension, is poured into a tub, and a fresh quantity of 
 water is added to the residue in the copper vessel ; the agitation is resumed, 
 and continued until all the dye ware is properly divided. On the large scale 
 various machines are used for this purpose, the construction of which differs 
 very greatly : some of these contrivances are arranged upon the same prin- 
 ciple as the hand-mill just described. One of the best machines consists of 
 an iron or copper cylinder, placed horizontally, and made to turn on a hori- 
 zontal axis ; inside of this cylinder are placed two rows of loose, movable, 
 cast-iron cylinders, consisting of loose pieces, discs as it were, and set in the 
 longer axis of the larger hollow cylinder. Since the tangential lines of the 
 cast-iron cylinders and of the internal surface of the hollow cylinder differ, 
 
 2 h 2 
 

 Xi*3*£#': 
 
 WlflfW 
 
 468 
 
 DYEING AND CALICO PRINTING. 
 
 being greater than that of the cast-iron cylinders, the result, on motion being 
 imparted to the hollow cylinder, is that the inner cast-iron cylinders turn in a 
 direction opposite to that of the large hollow cylinder, and the consequence is 
 an enormous friction, which reduces the softened indigo to a pulp. This 
 apparatus works very well if indigo of superior — or at least good ordinary — 
 quality is to be operated upon, since these are readily and uniformly penetrated 
 by water ; but low qualities of indigo are often with difficulty, or even not at 
 all, penetrated by water, and if brought into this apparatus the result is to 
 convert the ware into a plastic, tough, semi-dry, clay-like mass, which soon 
 causes the stoppage of the proper working of the apparatus. In order to 
 guard against this contingency the previously softened ware is submitted to a 
 preliminary grinding process, by means of a mechanical contrivance consisting 
 of two circular cast-iron discs, placed horizontally and near to each other, but 
 with a perceptible open space left between : by means of suitable machinery a 
 rapid movement is imparted, one of the discs moving from right to left, the 
 other from left to right ; on the internal surfaces of the discs grooves are cut, 
 somewhat like those on the stones used for grinding corn. The indigo is ad- 
 mitted to the spaces between the two discs, and is squeezed out at the 
 circumference as a kind of thickish paste. This machinery may be applied 
 for the pulverisation of other solid substances, and acts very satisfactorily. 
 
 Indigo can only be used for colouring textile fibres after having been pre- 
 viously rendered soluble, and this can, as yet, be effected only by the two 
 methods already described, — the reduction process, and the action of concen- 
 trated sulphuric acid. In the first method the process of dyeing is based upon 
 the regeneration of the indigotin, which then adheres to, and probably unites 
 with, the fibre : by the second method the colouring matter has itself entered 
 into a combination from which it cannot be again separated, so that the dyeing 
 process is really carried on with a substance altogether distinct from the 
 original indigo, and possessing other properties. 
 
 Fixing Indigotin by the Reduction Method. 
 The hydrogenisation of indigotin and the combination of white indigo with 
 an alkali, or an alkaline earth, render it soluble, so that it can be made to 
 penetrate textile fibres, and when the white indigo is, by suitable oxidising 
 agents, re-converted into blue indigotin, that substance, becoming insoluble, 
 is fixed in the pores of the textile fibres in such a manner as to adhere firmly 
 and be capable of withstanding washing and soap. This reaction is employed 
 for the purposes of dyeing in the following manner : — 
 
 1. The indigotin is reduced and dissolved by an alkali, and the fabric im- 
 
 mersed in the solution ; ordinary indigo-vat. 
 
 2. The solution is printed or painted on some portions only of the fabric, 
 
 by the aid of a pencil — so-called pencil-blue. Pencil-blue is supposed 
 to be so called because originally used for the "enlummage" of madder 
 chintz work, being pencilled into white spaces left for that purpose, 
 such as leaves, &c. The pencil was simply a small, flat, blunt-pointed 
 piece of wood. 
 
 3. The white indigo is precipitated in the form of a paste, in combination or 
 
 mixture with a very strongly reducing metallic oxide (commonly hy- 
 drated protoxide of tin), whereby the too rapid oxidation of the white 
 
REDUCTION OF INDIGO. 
 
 469 
 
 indigo is prevented. This paste, properly thickened, is printed on the 
 fabric, which is next passed through an alkali-bath, lime water or soda 
 solution, which has the effect of replacing the oxide of tin and forming 
 a soluble combination of white indigo, which latter penetrates the fibre 
 and becomes fixed by a subsequent oxidation process ; so-called preci- 
 pitate or fast blue. 
 4. Indigo, previously pulverised, is printed on the tissue, and this latter is 
 next placed in such condition that the indigo may become dissolved 
 and reduced locally, after which it is fixed by a subsequent oxidation ; 
 so-called China blue. 
 It is quite clear that for each of these methods any of the known processes 
 of reduction may be used, care being, of course, taken to apply that which is 
 practically the most advantageous. 
 
 The greatest consumption of indigo is for forming the blue vats in which 
 woollen or cotton goods are dyed, by simply immersing them in the solution 
 of white indigo. The same vat is not equally adapted for wool and calico, 
 and, as will be seen in the following details, there is a wide difference in their 
 composition. 
 
 Reduction of Indigo; Theory of the Indigo-Vats. 
 
 The most convenient method of reducing indigo for dyeing calico and cotton 
 yarn is based upon the action of hydrated protoxide of iron in the presence of 
 lime, since it possesses, when recently precipitated, the property of reducing 
 indigo, provided lime be simultaneously present. Any other caustic alkali 
 would answer the purpose, but lime is preferable on account of its cheapness, 
 and because it gives to the vats greater stability, the oxidation of the indigo 
 being greatly lessened, owing to the fotmation of a thin film of carbonate of 
 lime on the surface of the liquid, and, secondly, because with lime the 
 chemical activity is less intense. The very rapid alteration of vats made up 
 with caustic soda prohibits its use in dyeing yarn and tissues in the indigo-vat 
 (vat-blue), and also prohibits the use of reducing agents, which are more 
 advantageous than hydrated protoxide of iron, but do not act in the presence 
 of lime. Lastly, but not least, we ought to observe that experience has 
 taught that the lime compound of white indigo yields its colouring matter 
 more readily and completely to the fibre than the corresponding soda com- 
 pound, and, as a consequence, the vat is more completely exhausted, even 
 when quite cold. The hydrated protoxide of iron is formed in the vat 
 itself, by the action of the slaked lime upon the green copperas employed. 
 This latter salt should not contain any sulphate of copper, because the oxide 
 of that metal acts as a most energetic oxidising agent on the reduced indigo, 
 which, therefore, would be precipitated in the vat itself. Basic sulphate of 
 peroxide of iron and sulphate of alumina also ought not to be present in the 
 copperas, because these substances would seize upon a portion of the lime 
 and a<5t as inert matter. 
 
 Copperas in solution is readily purified by boiling it with clean metallic iron, 
 which precipitates any copper present in the state of metal, while any basio 
 salt of peroxide of iron is reduced to a protoxide salt. 
 
 The ingredients of the copperas-vat are — Water; pure or previously purified 
 green vitriol ; indigo reduced to a homogeneous and impalpable creamy paste ; 
 
■fT-rfCS«i -C-iW 
 
 WWBBI ISSi 
 
 IBWW 
 
 470 
 
 DYEING AND CALICO PRINTING. 
 
 and lime of good quality, slaked just before use, and sifted. The reaction of 
 these substances upon each other takes place in the cold, but is greatly aided 
 by a moderate elevation of temperature. It is not possible to give precise 
 practical instructions as regards the proportionate quantities of each of these 
 materials to be employed, because these vary in almost every dye-works, 
 and in many instances they are trade secrets. When the vat is to be used for 
 plain dyeing, it is usual to take the quantities of lime and copperas in excess 
 of what is indicated by theory, because by proceeding thus there is formed an 
 excess of hydrated protoxide of iron, and enough lime is left to serve the 
 purpose of again reducing and re-dissolving any indigo which becomes 
 oxidised and insoluble. This proceeding is greatly promoted by stirring up 
 the contents of the vat, as is usual after some pieces have been dyed. The 
 following examples may serve the purpose of exhibiting the proportions of the 
 ingredients employed by dyers in setting vats : — Indigo, 1 part ; crystallised 
 sulphate of iron, 3 parts ; carefully slaked lime, 3 parts. Some dyers prefer 
 to employ a larger quantity of lime than of sulphate of iron, and make the 
 mixture — Indigo, 2 parts; crystallised sulphate of iron, 5-5 parts; lime, 
 6'5 parts. 
 
 When white indigo is intended to be used for printing, the following mixture 
 answers the purpose : — Indigo, 1 part ; sulphate of iron, 2 parts ; lime, 3 parts ; 
 but these proportions do not answer well for dyeing. 
 
 We stated, upon the authority of Berzelius, that an excess of lime is 
 injuiious, and tends to occasion a considerable loss of colouring matter, 
 because the white indigo can — while combining with lime in a higher pro- 
 portion — form an insoluble basic body, which, by settling to the bottom of the 
 vat along with the rest of the sediment, becomes lost for the purpose of 
 dyeing. Although the correctness of this statement need not be doubted, he 
 has overrated its practical bearing, because the practical experience of M. E. 
 Schlumberger, who purposely studied this point on the large scale, does not 
 agree with this statement of the eminent Swedish savant. It often happens 
 that in practice on the large scale matters differ from laboratory experiments, 
 and Berzelius is quite correct in recommending to avoid an excess of lime and 
 sulphate of protoxide of iron, because it increases the bulk of the sediment 
 without any real advantage. 
 
 As regards the method of making the mixture, this also differs in different 
 dye-works. The most rational plan is to mix the indigo in a pasty state with 
 the milk of lime, and next to add gradually, and while the contents of the vat 
 are being stirred, the solution of copperas. By following this plan, the white 
 indigo, while being gradually formed, is at once dissolved by the excess of 
 lime : but when the quantity of substances is rather large this method is 
 difficult of execution, on account of the contents of the vat becoming very 
 thick and pasty, and difficult to stir at first, and it is therefore preferable to 
 mix the indigo with the solution of the green vitriol, and to add the milk of 
 lime next gradually. The operation, to be successful, requires only a small 
 quantity of water ; the milk of lime should be used freshly prepared and still 
 warm, owing to the heat developed while the quick-lime is being slaked, and 
 the green vitriol is best dissolved in hot, or even in boiling, water. After the 
 mixture has been made it is left quietly standing for several hours, care being 
 taken to stir the liquid occasionally. As soon as the liquid becomes an olive- 
 
THEORY OF THE INDIGO-VATS. 
 
 47i 
 
 yellow the reduction is complete, and the vat ready for use. According to 
 Schwartzenberg the liquid contains in solution reduced indigotin, some indigo- 
 red, and all the gluten, with a trace of the brown matter. The sediment 
 contains the whole of the indigo-brown combined with lime, the greater part 
 of the indigo-red, some gluten, a very small quantity of indigotin, sulphate of 
 lime, and hydrated peroxide of iron. The same author states that indigo-red 
 does not sensibly affect the dyeing process, but that this assertion is an error 
 is known to all practical blue dyers who have used qualities rich in red 
 colouring matters. 
 
 The vats in large dye-works are oblong cisterns, made of flag-stones large 
 enough to form the four sides and the bottom, so that there are joints only at 
 the corners. They are 9 feet long, 3£ wide, and 9 deep. 
 
 In many dye-works small tanks (tubs) only are used, the size being such as 
 only to suit a piece of goods of some 50 metres in length : these tanks are 
 constructed of wood, the shape being cylindrical. The piece or pieces of 
 goods to be dyed are stretched on a peculiarly constructed apparatus, con- 
 sisting of a wooden pole, bearing at each of its ends another piece of wood, 
 shaped as a star, with six or eight arms ; one of these is made movable by 
 means of a screw : the arms are provided with hooks, on to which the goods 
 are fastened. When small tanks or tubs are used this arrangement admits of 
 readily transferring the wooden framework containing the goods from one tank 
 to another. 
 
 Some manufacturers of colours precipitate the indigotin from old vats, 
 and employ it again in making up new vats. This operation is conducted 
 as follows : — The clear liquid as well as the sediments of the vats are, by 
 suitable means (pumps or other contrivances), poured over into very large 
 wooden tanks, and therein diluted with a large quantity of water ; sulphate of 
 iron and lime are next added, in such quantities as to cause the reduction, as 
 well as complete solution, of all the indigo present, a laboratory assay being 
 made of the old vat residues, so as to have some guide to the quantity present 
 and to the ingredients required to be added. The contents of these tanks are 
 thoroughly stirred, and next left to settle ; the clear liquid is made to run in 
 thin layers over shallow wooden troughs, so as to expose as much surface of 
 liquid as possible to the action of the air ; hydrochloric acid is added, and the 
 precipitated blue indigo is collected on filters, consisting of woollen blankets 
 stretched in suitably constructed wooden framework. The sediment left in 
 the tanks is repeatedly treated with water, and some lime and sulphate of iron 
 are also added, and thus the indigo is as much as possible recovered. 
 
 Calico, linen yarn, linen thread, and hemp yarn or thread, are always 
 dyed, if with indigo, by means of the cold green vitriol vat : a simple im- 
 mersion in the vat is sufficient to produce, after proper exposure to air, a 
 uniform blue colour; and by varying the strength of the vat, and the length of 
 time of each immersion, it is possible to obtain, as may be desired, a series of 
 shades from the very lightest sky-blue to a tint so deep as to appear nearly 
 black. The length of time allowed for the immersion of the goods has a great 
 influence on the quantity of indigotin which becomes fixed. The tissue 
 attracts by its pores indigotin, and this attraction is the cause that the vats 
 become exhausted of colouring matter long before all the liquid which serves 
 the purpose of keeping the dye-stuff in solution is absorbed. 
 

 472 
 
 DYEING AND CALICO PRINTING. 
 
 Since it is of the highest importance that the dyed goods should be evenly 
 coloured, it is, in the first place, best to moisten the goods first uniformly 
 with water, and it is next very important that the goods should be very 
 uniformly fastened and stretched on the frames, and very uniformly pressed on 
 emerging from the vat ; lastly, inequalities in the exposure to air are to be 
 avoided. As a rule, the time of exposure to air should be precisely the same 
 as that of the duration of immersion in the vats, and that operation may vary 
 from five to fifteen minutes. 
 
 The fastness and uniformity of the shades is promoted by operating gra- 
 dually, — that is to say, beginning with immersion in weaker vats, and going 
 by degrees to stronger, whereby the penetration of the indigotin into the 
 centre of the fibres is rendered more complete. The tissues to be dyed ought 
 to be very well bleached and very dean, since any fatty matter or dirt which 
 may adhere ads as a resist, and thus prevents uniformity of shade. After 
 dyeing and exposure to air, the goods are passed through a bath containing 
 dilute sulphuric acid (sp. gr. 1-007 t0 I-OI 3)i in order to remove any carbonate 
 of lime which has been precipitated by the carbonic acid of the air, and 
 also to aft as a clearing. They are next washed in pure cold water, and 
 dried. 
 
 Vat-dyed blue goods are considerably improved in appearance by being 
 passed through hot milk of lime, or by treatment with alkalies, whereby, in 
 all probability, some yellow matters are eliminated. It is on this account 
 that such goods are frequently passed through a soap-bath. 
 
 Vat-dyed goods, consisting of fibres of vegetable origin, may be combined 
 with white or otherwise coloured patterns, which can be done by two entirely 
 distinct processes : — In some instances there is printed on the goods, previous 
 to blue vatting, a preparation technically called a resist, or reserve, whereby 
 the fixation of indigotin is prevented upon the spots where such preparation 
 is deposited; in other instances, again, the indigotin of the uniformly blue- 
 dyed goods is removed by suitable means, viz., chemical compounds on such 
 portions of the cloth as are brought under the influence of these substances. 
 This proceeding is termed a discharge method. 
 
 The resists are either such as act mechanically only by preventing the pene- 
 tration of the indigotin into the fibre,— in this way wax and pipe-clay aft, — or 
 they exert a chemical aftion, setting up an energetic oxidising aftion which 
 causes the oxidation of the indigotin before it has had time to reach the fibre. 
 Such is the mode of action of salts of copper and of bichloride of mercury; but 
 *he reader should bear in mind that this classification does not apply rigorously, 
 because we are acquainted with many substances which act simultaneously 
 as mechanical resists and chemical discharges ; the copper salts, for instance, 
 while oxidising white indigo and precipitating on the- tissue a thin layer of 
 blue indigotin (viz., in the vat itself), cause thereby the formation of a more 
 or less impermeable layer, that layer being the blue indigotin, which, however, 
 does not adhere to, neither is in any way fixed on, the fibre. The salts of 
 zinc and aluminium, which are frequently employed, furnish simultaneously a 
 deposit of white indigo and a gelatinous envelope, consisting of the hydrated 
 oxide of either metal. The following'materials act more or less in a similar 
 manner: — Arsenic acid, acid arseniates and.'phosphates, boracic acid, salts of 
 lead and of peroxide of iron. Copper and lead soaps act simultaneously as 
 
THEORY OF THE INDIGO-VATS. 
 
 473 
 
 chemical and mechanical resists. In practice, however, the various substances 
 mentioned are suitably mixed, and so blended together as to make the result 
 satisfactory. 
 
 The reader will find below instances given of the mixtures in a<5tual use. 
 The thickeners play in themselves a great part in this matter, and it is of the 
 highest importance to understand the mode of action of every thickener and 
 the proportion which should be mixed with the resist compound : it is clear, 
 therefore, that the making of a good resist depends on understanding the 
 various quantities of the constituents of the resist, calculated as well in 
 reference to the strength of the vat as to the depth of shade to be reserved. 
 It is a main condition that a resist should become hard immediately on the 
 goods being immersed in the vat ; if the resist becomes soft, the consequence 
 is that the colour runs. The acidity of the resist mixture should therefore be in 
 proportion to the alkalinity of the vat : a strongly acid resist, which would harden 
 readily in a strongly alkaline vat, would soften and run in a feebly alkaline 
 vat; on the other hand, again, a nearly neutral resist, which might do for a 
 weak vat, would be useless in a strong one. It is clear, therefore, that the 
 choice of this or that salt or base is far from indifferent in this matter : sul- 
 phates and nitrates are stronger resists than acetates, which latter, in their 
 turn, suit very well for weak vats. The most generally used white resist is 
 made up of pipe-clay, gum, verdigris, and sulphate of copper : the goods to 
 be dyed blue with a white pattern (white resist) are commonly not strongly 
 bleached, but simply boiled in soda-lye, because in that state they are better 
 and more rapidly dyed. Such goods are, moreover, submitted to another 
 operation previous to being immersed in the vat ; they are passed through a 
 weak, very fluid, starch paste, to which some sulphate of copper and nitrate 
 of ammonia are added, with the view first to render the pieces uniformly 
 moist, and next to promote oxidation as well as the penetration of the indigo. 
 After this operation the goods are lightly dried and calendered ; next, the 
 resist is printed on; the fabric again dried, and after that vatted. The fabric 
 is next cleared in a weak solution of tepid sulphuric acid, sp. gr. 1*013. 
 
 When the resist, instead of being applied to a white ground, is printed on 
 to a piece already blue dyed, the result will be the production of a light blue 
 design upon a deep blue ground. 
 
 When a piece of goods has been arranged so as to leave, after vatting, white 
 portions, it is clear that on these portions there may be printed steam-colours, 
 or even a mordant, and that the piece so prepared may be treated as if the 
 whole of it were white, the result, after dyeing, being the production of a 
 piece upon which several colours may be present on a blue ground. This 
 kind of work requires a very nice adjustment of the engraved cylinders. If, 
 instead of an ordinary white reserve, there is employed a composition which 
 contains acetate or nitrate of lead and a salt of copper, the result will be that 
 by vatting a portion of the oxide of lead becomes fixed ; when, after the 
 vatting, the fabric is first immersed in dilute sulphuric acid, and next in milk 
 of lime, and afterwards dyed in a bath containing a saturated solution of 
 bichromate, with or without lime, the final result will be the production of a 
 yellow or orange pattern. When this resist is printed on previous to blue- 
 vatting, and the piece afterwards dyed in bichromate, there will be produced a 
 green-coloured pattern surrounded by deep blue. Again, a reserve may be 
 
■EBBS 
 
 474 
 
 DYEING AND CALICO PRINTING. 
 
 employed which contains the elements of the red mordant : after ageing, the 
 piece is vatted, next washed in a running stream, and after that dyed in 
 madder, the result being the production of a red pattern on a blue ground. 
 
 These instances prove the great variety of patterns which can be produced. 
 The details of these operations are entirely matters of practice, requiring 
 very nicely adjusted mechanical arrangements. The following are receipts 
 for different resists: — 
 
 For Deep Blue. — Water, 4 litres; sulphate of copper, 1*25 kilos. ; acetate 
 of copper, 500 grms. ; nitrate of copper, 875 grms. ; alum, 240 grms. ; 
 pipe-clay, 2 - i25 kilos.; calcined starch, 1*25 kilos. 
 For Medium Blue. — Water, 4 litres ; sulphate of copper, 500 grms. ; 
 acetate of copper, 250 grms. ; nitrate of copper, 500 grms. ; alum, 
 240 grms. ; pipe-clay, 2 kilos. ; calcined starch, 1 kilo. 
 Red-Resist, so-called Lapis. — Red liquor, sp. gr. 1*07, 12 litres; Senegal 
 gum, from 2 to 3 kilos.; pipe-clay, 4 to 6 kilos.; olive oil, 1 kilo. ; 
 sulphate of copper, 1 kilo. ; nitrate of copper, 500 grms. ; sal- 
 ammoniac, 1*5 kilos. 
 White Lapis. — No. 1 : Lime juice at a sp. gr. of nog, 5 litres ; thickened 
 lime juice, thickened with 1*5 kilos, of gum upon 2 litres, 1-5 litres; 
 sulphate of copper, 1 kilo. ; pipe-clay, 3 kilos. No. 2 : Water, 
 2 litres; sulphate of zinc, 1 kilo.; pipe-clay, 725 grms.; gum Senegal, 
 500 grms.; solution of nitrate of copper, sp. gr. 1-52, 0-12 litre. 
 For White Under Mordants, and for Blue Contours. — Caustic soda 
 solution, sp. gr. 1-070, 8 litres; arseniate of potassa, 3-5 kilos.; 
 corrosive sublimate, 500 grms. ; pipe-clay, 3 kilos. ; gum Senegal, 
 1*5 kilos. 
 The so-called discharge method is in many respects rather inconvenient ; 
 it does not admit of very finely engraved patterns ; and it requires very strong 
 vats to prevent the running of the discharges. The application of the latter 
 is always preceded by dyeing the goods uniformly blue, the strength of the 
 vats being of very little importance in this process. The employment of dis- 
 charges is based upon the property of energetic oxidising substances, 
 whereby the indigotin is converted into soluble isatin. The most generally 
 applied discharge is chromic acid, but since that substance cannot be used in 
 a free state, because it will be immediately acted upon by the thickener, which 
 would convert it into chromic oxide, a circuitous process is used. Upon the 
 woven tissue bichromate or neutral chromate of potassa is padded, and when 
 dry there is printed on the pieces a composition, chiefly made up of an acid, 
 whereby the chromic acid is set free ; the strength of the chromic acid 
 solution must be regulated according to the intensity of the blue colour pre- 
 viously imparted to the cloth. A medium blue requires an almost saturated 
 solution of the chromate ; the goods padded with bichromate cannot be dried 
 in the open air, at least not by direct exposure to sunlight, because that would 
 cause the destruction of much of the indigo. Oxalic acid is very commonly 
 employed as the chief constituent of the paste intended to set the chromic 
 acid free ; it is thickened with gum, dextrin, or starch, to which some pipe- 
 clay is added ; in some instances nitric, sulphuric, or tartaric acid is applied. 
 The decolouration of the portions of the blue colour of the cloth, where the 
 acid composition has been fixed, is almost instantaneous ; the goods are next 
 
INDIGO-VATS. 
 
 475 
 
 washed in warm water, wherein chalk is kept suspended, thereby to saturate 
 the excess of acid. 
 
 Instead of employing as discharges the salts of chromic acid just named, 
 chromate of lead is sometimes applied, being printed on with a suitable 
 thickener, and, after having become dry, the goods are passed through a 
 rather strong solution of moderately warm hydrochloric acid. In this case it 
 is not so much chromic acid as chlorine set free, which afts as a discharge 
 and decolourises the indigo. Instead of chromate of lead hydrated peroxide 
 of manganese is sometimes applied. 
 
 M. Mercer discovered that a mixture of red prussiate of potassa (ferricyanide 
 of potassium) and caustic potassa or soda would discharge indigo-blue in a 
 very perfeft manner ; but on account of difficulties in the application and of the 
 costliness of this process it has not been much employed. If the materials be 
 mixed and printed on a blue the colour is at once discharged, and only requires 
 washing off; but the mixture has a very energetic aftion upon all thickening 
 matters, and is very irregular in its results ; on the other hand, it does not 
 impair the strength of the fibre. The discharges upon indigo-blue can be 
 made to aft as mordants, or colours to produce a coloured design instead of a 
 white one. For example, if acetate of alumina be mixed with the discharge, 
 and the alumina fixed in the washing off, it may be dyed up in madder or 
 garancin to produce a coloured discharge. Sometimes the discharge and 
 resist are combined together ; for instance, on light blue ground are printed 
 simultaneously in the first place an ordinary resist, and, secondly, the same 
 resist, to which has been added bichromate of potassa and hydrochloric acid; 
 when the fabric so prepared is again vatted the result will be a deep blue 
 ground, whereon is a pattern of light blue and white. 
 
 In order to give an idea of the composition of the materials used for dis- 
 charging indigo-blue we quote the following: — Chrome liquor consists of — 
 Water, 2 litres, wherein are dissolved 500 grms. of yellow chromate. The acid 
 composition contains — Tartaric acid, 3 kilos. ; oxalic acid, 250 grms. ; calcined 
 starch, 4 kilos. ; nitric acid, 500 grms. ; water, 4 litres. This last composition is 
 printed on by rollers ; the wet pieces, rolled up between a loosely-woven cloth, 
 are immersed momentarily in water, and as soon as white becomes apparent 
 are placed at once in tepid water containing chalk. 
 
 Before we proceed to consider the combinations of other colours which may 
 be formed by the aid of the vat-dyed materials, we give here a short outline 
 of what has been said on dyeing with indigo : — The usual method of dyeing 
 cotton self blue is to fill with water large stone or wooden tanks, and dissolving 
 therein 2 parts of sulphate of protoxide of iron, adding 1 part of finely-ground 
 indigo, and 3 parts of hydrate of lime. After having stirred the whole well 
 for several hours, pieces of calico which have been hooked on a frame and 
 dipped in lime-water,* in order to moisten them equally all over, are plunged 
 for some fifteen minutes into the vat, when the blue indigo which has been 
 converted into white indigo by the protoxide of iron, and rendered soluble by 
 the excess of lime, fixes itself on the fibre, and on the latter being afterwards 
 exposed to the atmosphere re-absorbs oxygen, and becomes blue. When 
 white patterns are required the pieces are printed before dyeing with what is 
 
 * This is often used in preference to ordinary water, in order to make sure that there be 
 excess of lime. 
 

 476 DYEING AND CALICO PRINTING. 
 
 called a "reserve" or " resist," that is, a composition which prevents the 
 colour from fixing itself on the fibre ; the chief ingredient for that purpose is 
 sulphate of copper, which acts by prematurely oxidising the indigo, and thus 
 prevents its fixation. In both cases the pieces are passed through a weak 
 sulphuric acid bath to insure the perfect fixation of the indigo. Formerly the 
 copper thereby liberated from the fabrics was completely lost, but Mr. J. Leese 
 devised, some years ago, a method of saving this metal ; to effect this, the 
 diluted solution of sulphate of copper is made to filter through vessels con- 
 taining wrought-iron turnings ; the acid dissolves the iron, which may be 
 used as sulphate of protoxide of iron for future operations, whilst the copper 
 deposited may be used again either to prepare sulphate of copper or utilised 
 in another manner. As an instance of the importance of small savings, it 
 may be stated that by this ingenious but apparently trifling improvement one 
 firm alone saved at least £3000 a year. 
 
 Dr. F. C. Calvert effected, some years ago, an economy in this branch of 
 calico printing and dyeing, consisting in extracting from the cold indigo-vats, 
 which were considered to be exhausted, a certain percentage of the indigo 
 originally employed. Dr. Calvert observed that a green insoluble flocculent 
 matter, which was considered by chemists and printers to be simply oxide of 
 iron, was in reality a compound of indigo and iron. In order to recover this 
 he devised the following simple method : — The green pulp is conveyed from 
 the exhausted vats into a general receptacle, and there mixed first with a 
 small quanity of hydrochloric acid, so as to remove the excess of lime, 
 allowing the green pulp to settle and running off the liquor. The green puip 
 thus purified is next treated with strong hydrochloric acid, whereby chloride 
 of iron is produced and indigo liberated, which, after having been washed 
 with water, is again fit for use. 
 
 Although in a later portion of this chapter more details will be given on 
 printing with indigo, we give here the following brief outline, which is one of 
 great difficulty, but successfully carried out by various methods : — That usually 
 employed consists in mixing very finely powdered indigo with orpiment or 
 protochloride of tin and a caustic alkali, a process which is further facilitated 
 by printing the pieces in an atmosphere of coal-gas, as first devised by 
 Mr. Bennett Woodcroft, and carried out by Messrs. T. Hoyle and Sons, of 
 Manchester. Of late years Mr. J. Leese, of the firm of Kershaw, Leese, and 
 Co., has succeeded in applying the following method, first devised by Fritzsche : 
 — The indigo is ground to an impalpable powder, and then mixed with glucose, 
 lime, and caustic soda, in such proportions as are needed to produce the shade 
 required. These materials are all mixed cold, and the cloth when printed is 
 passed through a steam chest, wherein it is exposed for from 30 to 60 seconds. 
 In this short period the indigo is completely reduced, and thereby rendered 
 soluble in the alkalies. It enters, penetrates, and combines* with the fibre. 
 On emerging from the steam chest it becomes oxidised and fixed by exposure 
 to the atmosphere ; or the pieces may be immersed in a solution of an 
 
 * According to a series of experiments made in Java, the results of which have not been 
 made public, by the late Dr. Fromberg, aided by Dr. Croockewit and other scientific and 
 practical men, vegetable fibres, also wool, silk, and hair, are not only penetrated by porosity 
 through the fibre, but actually enter into chemical combination with the white indigo, and 
 form a definite compound therewith. 
 
INDIGO-VATS. 
 
 477 
 
 oxidising agent, such as dilute sulphate of copper, after which they only re- 
 quire to be washed, dried, and finished. 
 
 Indigo is frequently applied in combination with other dyes, the object 
 being the formation of green and other shades ; the combination of the 
 indigo-blue and chrome-yellow producing the so-called vatted green. This 
 operation requires four tanks ; the contents of the first tank consist of a 
 solution of 2 litres of subacetate of lead, of sp. gr. = 1*421, and a lime- 
 water, made up of 2*5 kilos, of lime with water, to form a liquid of a 
 sp. gr. = 1*020 ; the second tank contains pure water; the third tank is a cold 
 indigo vat, with 7*5 kilos, indigo; the fourth tank contains a liquid, made up 
 of 5 kilos, bichromate of potassa and 40 litres of vinegar. The operation of 
 dyeing is carried out in this manner: the goods or pieces are plunged for 
 three minutes in the first tank, rinsed in the second, next plunged for 
 five minutes in the third tank, and next rinsed in the fourth, wherein the 
 indigo is oxidised, and simultaneously the green dye brought out. The goods 
 are then washed in running water, next immersed in another bichromate 
 bath, again washed in cold water, after which the cloth is passed through a 
 cold caustic soda bath, containing for each piece a litre of caustic soda 
 solution at a sp. gr. of 1*070. After another wash the goods are dried and 
 are ready for packing when they have been calendered. In this way an even 
 and uniform green is obtained. If an acid discharge is printed thereon, and 
 the goods washed, and then, if desired, immersed in a solution of bichromate 
 of potassa and lime, the result will be the production of a white pattern, or 
 also of a yellow on a green ground. 
 
 Another kind of green ground is produced by mordanting previously vatted 
 cloth wUh acetate of alumina, and dyeing the so-prepared fabric next with 
 quercitron, yellow berries, or weld ; if instead of quercitron madder is 
 employed a very beautiful puce is produced. Not only the colours just 
 mentioned, but a great many others, can be fixed on a previously-vatted and 
 subsequently-mordanted cloth. Goods which have been first dyed with per- 
 oxide of manganese (manganese brown) possess the remarkable property of 
 taking up a far larger quantity of indigotin than they would take up if vatted 
 while white ; the result is the production of a black ground, whereupon it is 
 possible to bring out white, brown (bistre colour), and blue designs, either in 
 discharge or resist styles. Thus there may be formed : a bistre ground, 
 whereupon a resist having been printed gives after vatting a black ground and 
 bistre designs ; or bistre ground, whereupon is next printed a discharge for 
 white (an acid tin-salt), yielding after vatting a black ground, whereon are 
 blue patterns; the same result is obtained when upon the black ground (that 
 is to say, indigo-blue after and over bistre) a bistre discharger (viz., simply a 
 weak acid, which does not act upon the indigo) is printed. A bistre-brown 
 ground, with resist for blue, and simultaneously a discharge for brown, yields 
 white ; this effect is also produced by printing an acid (stronger) on the black, 
 in which case the peroxide of manganese causes the oxidation of the indigo, 
 i.e., its decolouration, while the former is simultaneously decolourised, 
 becoming converted into a soluble proto-salt of manganese. Combinations of 
 indigo and hydrated oxide of iron yield similar results, but are less easily 
 managed, and are not so beautiful. 
 
 What has been mentioned above concerning vat blues applies chiefly to 
 
■dbbhbBH 
 
 478 
 
 DYEING AND CALICO PRINTING. 
 
 calicos. Since linen and hempen tissues possess, generally speaking, less 
 affinity for dyes, some precautions are also necessary when they are to be 
 dyed with indigo by the self blue or vat process. These goods are, therefore; pre- 
 vious to vatting, either first passed through a thin starch pastel, to which some 
 salt has been added, or through weak lime-water, but rarely or never are these 
 goods printed, and the process is, therefore, simply one of uniform blue dyeing. 
 
 As regards the application of indigo to woollen fabrics, these are always 
 vatted, and, in fact, a very large proportion of woollen cloth is grounded by 
 means of the indigo vat ; more frequently woollen and worsted yarns than 
 woollen woven fabrics are vatted, but if the latter are thus treated it is only 
 a plain blue dye they receive, and no resists are applied. 
 
 According to general ideas prevailing among woollen dyers in this country, 
 the lime and copperas vat is not well adapted for woollen goods, and the 
 usual blue vat is made up in a different manner, viz. — Water, 500 gallons ; 
 indigo, 20 lbs. ; potash or soda, 30 lbs. ; bran, 9 lbs. ; madder, 9 lbs. The 
 water is heated to near its boiling-point ; the potassa, bran, and madder are 
 first introduced, and then the indigo previously very finely ground ; cold 
 water is added to bring the temperature down to 90 F., and the vat is kept at 
 that heat all through ; the ingredients are very well stirred every twelve 
 hours, and the vat should be ready for use in forty-eight hours after settling. 
 This vat does not work longer than a month, and is somewhat expensive on 
 account of the loss of potash. Another vat, much more manageable and 
 lasting, since it may be worked for two years without emptying, being 
 freshened up as required, and known in France as the German vat, is made 
 up of 2000 gallons of water, heated to 130° F. ; 20 lbs. of crystals of soda, 
 2j pecks of bran, and 12 lbs. of ground indigo are added, and then the mixture 
 well raked up ; in twelve hours a fermentation sets in, bubbles of gas arise, 
 the liquid has a sweetish smell, and has become greenish ; 2 lbs. of slaked 
 lime are now added, the liquid well stirred, the vat heated again, commonly 
 by the aid of steam, and covered up for twelve hours, when a similar quantity 
 of bran, indigo, soda, and again a little lime are added ; in about forty-eight 
 hours after the setting the vat may be worked, but because the reductive 
 power of bran is rather feeble, an addition of 6 lbs. of molasses is made. If 
 the fermentation becomes too active, it is repressed by the addition of lime; 
 if too sluggish, it is stimulated by the addition of bran and molasses, and, 
 like all other blue vats for wool, is worked hot. In France, however, the 
 copperas and lime vat is used for wool also, though not exclusively. 
 
 Silk is rarely, if ever, dyed h!ne by the aid of the lime and copperas vat ; in 
 fact, generally speaking, the textile fibres of animal origin are dyed by means 
 of so-called pastel, woad, urine, and Indian vats. The reduction of the 
 indigotin is, in all these instances, the result of a peculiar fermentation called 
 into existence in an alkaline liquor by the aid of substances containing much 
 nitrogen, and also by the aid of suitable carbohydrates (sugar, &c). We know 
 that under these conditions sugar is rapidly converted, provided the tem- 
 perature be sufficiently elevated, into butyric acid, while carbonic acid and 
 hydrogen are simultaneously set free : the latter substance combines in the 
 nascent state with the indigotin, and the white indigo is rendered soluble in 
 the alkali present in the liquid : the fermentescible carbohydrates are 
 derived from bran, madder, and sometimes molasses ; the nitrogenous matter 
 
INDIGO-VATS. 
 
 479 
 
 is obtained from the pastel or woad, which is sometimes added in large quantity 
 to the liquid in the vats ; this substance then also yields the indigotin it 
 contains. 
 
 In those vats wherein pastel is not employed the nitrogenous matter is 
 derived from the bran : sometimes putrefying human urine is employed, for the 
 sake partly of the alkali it contains (viz., carbonate of ammonia), and also for 
 the organic nitrogenous matter, which acts as a ferment, while the former 
 plays the part of a solvent for the white indigo. 
 
 Since the phenomena attending fermentation are of a complex nature, even 
 in the most simple instance, it cannot be wondered at that, in such an 
 instance as is here given, there is not — as regards the success of the process 
 on an industrial scale — that certainty which attends the working of the lime 
 copperas-vats, and only a long practice and a lucky empiricism make sure of 
 success in a method which, scientifically considered, is not by any means fully 
 elucidated. It is on this account that the details which follow on this subject 
 are less extensive as to theory. 
 
 Pastel-vats, rarely employed in this country, vary in size from 2 to 2"5 metres 
 in diameter by 3 metres depth. The ingredients employed are 100 kilos, of 
 pastel, in the shape of balls ; the vat or tank is next filled with tepid water; 
 after which there are added 10 kilos, of madder,* 3 to 4 kilos, of bran, and 
 4 kilos, of slaked lime, well mixed with water to a thick creamy liquid ; some- 
 times also weld is added : this mixture is left standing for eight hours, after 
 which time the contents are thoroughly raked up, an operation which is 
 repeated every three hours : gradually a peculiar ammoniacal smell is given 
 off, and the surface of the liquid in the vat becomes covered with a bluish 
 scum, under which deeper blue-coloured veins are seen. Since these symptoms 
 indicate that the indigotin of the pastel has become dissolved, there is added 
 to the vat a quantity of 10 kilos, of finely-ground indigo, previously mixed to 
 a paste with water. If the fermentation becomes too active, as evidenced by 
 the size and quantity of the gas given off, it is moderated by the addition of a 
 small quantity of lime, while, if it is too feeble, it is quickened by the addition 
 of bran. A pleasant odour, neither too strong nor too weak, and abundance 
 of blue scum, are the signs of a proper condition of the contents of the vats. 
 The fabrics which are first immersed in a freshly-made up vat are less beauti- 
 fully dyed than those done afterwards, because the wool withdraws from the 
 bath some drab, brown, or yellow matters, which are the result of the reaction 
 of the various substances contained in the vat on each other. The woollen 
 goods, either pieces or yarns, are kept immersed in the vat for two hours, after 
 which time they are aired, and next washed : 100 kilos, of wool consume from 
 8 to 12 kilos, of indigo ; it is therefore evident that this loss or consumption 
 of indigo has to be restored after each day's work, and this is done by adding 
 every night a sufficient quantity of indigo along with some lime. After having 
 been thus kept up for some months, the vat, becoming gradually foul, is 
 exhausted, — that is to say, the dyeing process is continued until no more 
 colour is imparted to the wool ; after which the contents of the vat are run off, 
 the tank cleaned, and a fresh vat made up. 
 
 Another kind of vat is made up in the following manner : — 8000 litres of 
 
 * Madder in this case is only employed as a substance rich in sugar, and also because it contains 
 some nitrogenous matter. 
 
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 $?§SwS 
 
 »'-^i^i t -/ ^ ;.y^.»r&*U>-^gjC>;:-' 
 
 
 EH 
 
 480 
 
 DYEING AND CALICO PRINTING. 
 
 water and 200 kilos, of pastel are heated to g5° C. by the aid of steam ; after 
 some few hours there are added 6 kilos, of indigo, 8 kilos, of madder, 2 kilos, 
 of bran, 4 kilos, of lime, and 4 kilos, of potash (pearl-ash) : this mixture is 
 stirred up every three hours during the first forty-eight hours after having been 
 made : when the redudion of the indigo goes on well, there are still added 
 6 kilos, of indigo and 1 kilo, of madder. The contents of the vat are next 
 stirred up from time to time, and then left at rest till the next day. The 
 temperature of the vat is kept up at from 40 to 50 C. ; after each day's work 
 there is added to this vat a quantity of 1*5 kilos, of madder, and every third 
 day 6 kilos, of indigo. When this vat is once put into proper working order 
 it lasts for several months. 
 
 The so-called Indian, or potash vat., employed for dyeing wool and 
 silk, is made up with bran, madder, indigo, and potash ; the indigo is only 
 added to the mixture of water, and the other ingredients after they have 
 been heated up to go C. ; afterwards the temperature is kept up to between 
 30 and 40 C, the mixture being thoroughly stirred up once in every twelve 
 hours for a period of forty-eight hours. The colour of the liquid should be a 
 greenish-yellow with a coppery hue, and bluish-coloured scum on the surface. 
 The quantities employed are — Indigo, 8 kilos. ; potash (pearl-ash), 12 kilos. ; 
 bran and madder, each 3-5 kilos. In order to keep up this vat there are added 
 to it, when required, certain quantities of alkali, indigo, and madder. This 
 kind of vat is more readily managed, not so easily spoiled, and works quicker, 
 — that is to say, it is possible to dye three times as much wool in it in the 
 same time, and, moreover, the dyed fabric does not, on being washed in soap, 
 cast off so much superfluous dye as with the pastel-vats ; but this alkali-vat 
 has to be refreshed about every twenty-five to thirty days, because the potash 
 becomes soon saturated with the fat and grease of the wool. 
 
 More advantageous than the Indian is the vat generally known as the 
 German, employed not only in that country, but also elsewhere. To the 
 water, having been first heated to 95° C, are added 20 pailfuls of bran, 11 kilos, 
 of carbonate of soda, 5-5 kilos, of indigo, and 2-5 kilos, of lime just slaked 
 previously, while the temperature is kept up at from 40°to 50 C. : fermentation 
 sets in after about twelve hours ; the liquid gives off a somewhat sour smell, 
 becomes coloured a greenish-blue, and gives off gas-bubbles : from time to 
 time the same quantities of indigo, soda, and lime are added, and, moreover, 
 some 3 to 4 kilos, of molasses : the vat is fit for use after the third day. Since 
 soda is much cheaper than potash, this vat is more economical for that reason. 
 The German vat may last, in good working order, for fully two years. 
 
 The fermentation indigo-vats are subject to diseases, which are more espe- 
 cially to be feared with the pastel-vats. The more frequently occurring 
 diseases are due either to an excess or to a deficiency of lime : in the first- 
 named instance the colour of the liquid becomes more and more clear and 
 bright, the bluish scum decreases, and the odour disappearing, fermentation 
 stops, and the adlive principles are precipitated : when this defedt is discovered 
 in good time, it is remedied by the addition of sulphate of iron. In case there 
 happens to be a deficiency of lime, the fermentation becomes first too a&ive, 
 and next enters the putrescent stage. The liquid turns red, and, if vatted 
 cloth is plunged into it, it is soon decolourised. The only remedy for this 
 disease is to^heat the liquid to 90 , and to add lime ; if this does not arrest the 
 
INDIGO-VAT. 481 
 
 process at once, the vat is lost, and the contents have to be run away. The 
 mode of working these vats is as follows : — They are stirred up first thing in 
 the morning, when the scum is also removed from the top ; then, in order that 
 the goods to be dyed may not touch the sediment at the bottom, there is 
 placed in the liquid a net, made of thin strong twine, fastened to a wooden 
 hoop : the goods are dyed, immersed in the vat, inside this net ; the time of 
 immersion varies, but is generally from twenty to twenty-five minutes. When 
 withdrawn from the vat the goods appear greenish-yellow, but very soon 
 become blue on exposure to the air. The immersion is repeated as often as is 
 needed to produce the desired shade. The goods are afterwards washed, first 
 in acidulated water, next in a plentiful supply of clear water. 
 
 bilk is always dyed in the Indian vat, but, since the blue is never very deep, 
 Prussian blue cr the aniline blues are preferred, though indigo has the advan- 
 tage in fastness. 
 
 M. Leuchs* has suggested to do away with all the vats above mentioned, 
 and to utilise instead the property of pectin and pectic acid of reducing indigo 
 in presence of soda. Produces containing these pectic compounds are very 
 common in the vegetable kingdom, and the turniptribe yields them in abundance. 
 The suggestion is valuable, but has never been tried in practice, except on a 
 very limited scale. A large manufacturer in Belgium reports, in a private 
 communication, that when you have intelligent workmen this process is excel- 
 lent, but the prejudice of foremen stands in the way of its general adoption, 
 the fact being that they think no good can be done with cheap materials, — 
 rubbish as they term it, — as are turnips, mangolds, beets, and the like. Spe- 
 cimens of woollens and silks vatted in this manner are not only not inferior, 
 but, according to competent judges, superior to those done in the common 
 vats. In some exceptional cases the kind of vat above described as German 
 is used for cotton piece-dyeing : this is principally for thick and heavy goods, 
 into which the cold lime and copperas liquor-vat would not penetrate suffi- 
 ciently well. 
 
 An entirely new vat has been proposed by Messrs. Schutzenberger and 
 Lalande. Bisulphite of soda, standing at 30 to 35 Baume, is brought in 
 contact in a covered vessel with twisted sheet zinc or granulated zinc, filling 
 up to the top of the vessel without occupying more than one- fourth of its real 
 volume. After the lapse of about one hour the liquid is poured into an excess 
 of milk of lime, which precipitates the salts of zinc. It is stirred, and the 
 clear liquid drawn off either by filtration and pressure, or by decantation after 
 the addition of water. Air should be excluded as much as possible. By 
 mixing the hydrosulphite thus obtained with ground indigo and the amounts 
 of lime or soda needful to dissolve the reduced indigo, we obtain at once a 
 yellowish liquid containing no insoluble matter except the earthy impurities 
 of the indigo. One kilogramme of indigo may be thus reduced so as to form 
 a solution not exceeding 10 to 15 litres in volume. For dyeing, a certain 
 quantity of the reduced indigo solution is run into a vat filled with water. 
 This vat being clear in its entire depth, the operation of dyeing involves no 
 loss of time. The excess of hydrosulphite constantly reduces the scum of 
 oxidised indigo forming on the surface of the dye-bath, the strength of which 
 can be kept up during working by successive additions of the concentrated 
 
 * " Polytechnisches Notizblatt," 1S65, p. 277. 
 

 Wtilffg 
 
 482 
 
 DYEING AND CALICO PRINTING. 
 
 indigo solution. Thus the required shade can be obtained with the smallest 
 possible number of dips. This vat gives shades more solid and clear than can 
 be obtained with the old vats, and enables the dyer to produce upon wool very 
 light blue bottoms, which are ordinarily got by means of sulphate of indigo, 
 and are in consequence much more fugitive. The authors propose to print 
 with an alkaline solution of reduced indigo, suitably concentrated and 
 thickened, containing a large excess of hydrosulphite of soda. The presence 
 of this salt tends to keep the indigo-blue reduced, which otherwise tends to 
 become oxidised during the time of printing. This part of the process can be 
 carried out in common air, and with an ordinary machine, the oxidation being 
 so slight that after an hour's work the remnant of the colour is still yellow 
 and soluble. By thus printing on reduced indigo immediate fixation is 
 secured, and the entire colouring matter is utilised. Experience has proved 
 that, for equal shades, 50 to 60 per cent less indigo is consumed with the new 
 process than with the old. The shades obtained are more beautiful and solid, 
 and the impression is better defined. The new indigo-blue, requiring no sub- 
 sequent fixing process, can be printed along with a great number of other 
 colours, such as aniline black, garancin, colours obtained by dyeing or 
 steaming, catechu shades, chrome colours, colours fixed with albumen, &c. 
 Thus new styles may be created which would be difficult to execute in any 
 other manner. The blue printing colour is formed by thickening, with gum or 
 any other suitable material, a sufficiently concentrated solution of white indigo 
 in an alkali, and adding to the mixture a sufficient quantity of hydrosulphite 
 of soda. After printing, the pieces are hung up for twenty-four hours to 
 oxidise, washed, and soaped. 
 
 We have now to consider the methods of fixing indigotin in printing, a 
 process solely applied to calico. The pencil-blue style dates back certainly 
 ninety or a hundred years, and no improvements have been made upon it 
 since the commencement. 
 
 Pencil-blue consists of reduced indigo, and is made by heating a mixture 
 of finely-ground indigo, orpiment, and potash. These latter substances form 
 a powerful deoxidising mixture, which speedily reduces and dissolves the 
 indigo. In a short time after mixing, the blue colour of the indigo disappears, 
 and gives way to a yellow, except at the surface, where the oxygen of the air 
 continually revives the indigo, causing it to assume a coppery-blue. The 
 avidity of this mixture for oxygen, whereby the indigo is restored to its blue 
 insoluble state, is so great that it cannot be exposed a moment to the air without 
 being covered with a scum or pellicle of blue indigo, and it is also the cause of the 
 great difficulty in applying pencil-blue in a regular and satisfactory manner. As 
 soon as the block or roller leaves the colour, and enters the air, the surface of 
 the colour is covered with a scum of indigo, which, being insoluble itself, can- 
 not enter the fibre of the cloth, and, lying on the surface of the soluble colour, 
 is a hindrance to its entering into the fibre. Peculiar arrangements have to be 
 made in applying this colour to prevent contact with the air; they are all 
 more or less defective, and the results are often irregular. In the old method 
 of applying it with a pencil, the pressure upon the fibres of the pencil (this 
 consisted of a piece of willow-wood stick, which, by means of a blow given 
 with a mallet on one of the ends, was somewhat split and splintered into a 
 
INDIGO. 
 
 483 
 
 fibrous mass) containing the blue could drive the film of indigo aside at the 
 very moment when the pure colour beneath could enter into the cloth and 
 unite with the fibre; but in either block or roller printing* the cloth and design 
 are perpendicular to each other, and the face of the colour comes in flat con- 
 tact with the cloth : the insoluble particles, being deposited first, hinder and 
 prevent the fixation of the others. Many ingenious constructions of reservoirs 
 and sieves for block printing have been made specially for this colour, and, 
 with the exercise of great care, it has been possible to print with some of 
 them, and obtain tolerably uniform results ; but they have not admitted of 
 general application. 
 
 There is less especial difficulty in printing pencil-blue with the cylinder. 
 Thousands of pieces are weekly printed in America, and a considerable number 
 here. The apparatus used is a " doctor-box." The blue oxidised layer of 
 colour is removed, and the engraved portions of the cylinder work in the green 
 solution last, and go thence at once to the cloth. 
 
 As an instance of the mode of making up a mixture for pencil-blue, we 
 quote the following for dark blue : — 10 gals, indigo-pulp, containing 40 lbs. 
 indigo; 40 lbs. yellow orpiment ; nj gals, soda-lye, at 70 Tw. ; 18.J gals, 
 water; 4 lbs. lime. Boil till yellow when spread on glass; let settle, and 
 thicken the clear with 120 lbs. gum Senegal. 
 
 We have already referred to Bennet Woodcraft's process, bearing upon the 
 production of a good dark blue by means of the rollers. The patentee, acting 
 under the knowledge that it was the oxygen of the air which — both on the 
 roller and on the colour — was the obstacle to neat and proper printing, pro- 
 posed to construct covered apparatus to surround the colour-box and roller, 
 and to receive the piece when printed ; and in all these spaces where the air 
 was in contact with the colour, he proposed to expel it by introducing common 
 coal-gas from the gas-mains, since, as a rule, this gas does not contain any 
 oxygen, or at least only a very small percentage,! it could not act upon the 
 colour, which it was supposed would then have a fair chance of entering the 
 
 * The difference between block printing and roller or cylinder printing consists in the fact 
 that while the block (generally a square piece of wood, upon one surface of which the 
 rcsired pattern is either cut en bas-relief, or is executed in a peculiar style by means of 
 copper wires projecting very slightly from the surface of the block) not only deposits the colour 
 upon the cloth, but to a greater or less extent forces it in, the cloth in cylinder printing (the 
 cylinders are made of copper, upon which the pattern is engraved) has to absorb the colour, 
 partly by capillary attraction and partly by the pressure of the lapping. The same colours do 
 not answer indifferently for block and roller styles. Block-colours can be worked usually 
 thinner (i. c, require less thickening— the reader should also bear in mind that the term colour 
 is often used in cases where really only a mordant is printed) than cylinder, or so-called 
 machine-colours, and it is possible to apply colours by block which could not well be applied 
 by cylinder. Among such colours are those containing insoluble matters, like pipe-clay, 
 sulphate of lead, &c. For heavy shades upon woollen cloth (flannel printing) the block has un- 
 doubtedly the advantage over the cylinder, because not only does wool demand much more 
 colouring matter than cotton to produce a shade of equal depth, but it does not absorb it so 
 quickly, since its fibres are less readily wetted than those of cotton, and it consequently does 
 not receive colour from the engraving in sufficient quantity. Dark blues, chocolate-browns, 
 greens, &c, on the finest class of French woollen cloth, require to be blocked two or three 
 times to receive sufficient colour for full heavy shades. 
 
 + It is not the place here to enter into details on this matter; but the fact is that, unless 
 under very exceptional conditions, gas manufactured on the large scale is never quite free from 
 some air. 
 
 2 12 
 
m 
 
 BHB 
 
 484 DYEING AND CALICO PRINTING. 
 
 cloth. The idea was good, but notwithstanding large sums of money have 
 been spent to give this process a fair trial, requiring as it does complicated 
 machinery, it has signally failed. Some of the causes of this failure are quite 
 unaccountable, so that the process was abandoned in despair, and has never 
 been worked for the last eighteen years. 
 
 We have now to turn our attention to an application of indigo known as 
 China blue, because the blue colour had a similarity to the well-known blue of 
 old China ware. It is produced by a process so extraordinary in its results 
 that it is impossible to conceive how or where it originated, and although 
 this application of indigo has now become obsolete, we cannot be justified 
 in omitting to enter into some details on this subject. 
 
 The theory of China blue printing is exceedingly simple : the indigo, reduced 
 to an impalpable powder, is thickened, and this mixture is printed on by means 
 of cylinders or blocks. After drying, the goods exhibit a more or less deep 
 blue pattern, according to the quantity of indigo employed : but this blue would 
 not resist even a rinsing in cold water. The next stage is therefore to reduce 
 and dissolve the indigotin on the spot, and thereby to cause it to penetrate 
 and combine with the fibre to be definitively fixed after a process of oxidation. 
 These operations have to be performed so as to preserve the snarpness of the 
 design and prevent any colour from running. The following means are 
 resorted to : — The cloth is first passed through a tank containing milk of lime, 
 next through one containing a solution of sulphate of iron, next through a 
 solution of soda, and, lastly, through weak sulphuric acid, which, while 
 dissolving the oxide of iron, causes the precipitat'on of the white indigo, and 
 aids also its oxidation. This is only an outline of the method to illustrate 
 the theory ; the pra&ice is essentially different, so as to secure success. In 
 the first place, the printer begins his operation with the preparation of standard 
 colour in the following manner:— He takes 4 kilos, of very finely-pulverised 
 and sifted indigo (for this special purpose the Caraccas indigo is preferred, 
 because, although it is less rich in colouring matter than Bengal or Java 
 indigo, it is more readily pulverised, and can be obtained in a powder as fine 
 as the finest ultramarine) ; acetate of iron, 10 litres ; sulphate of iron, 1 kilo. ; 
 water, 10 litres ; Senegal gum. 6 kilos.: this mixture is well stirred and passed 
 through a sieve, and whenever it is required for use, it is first well stirred. 
 This standard colour serves to prepare the following colours, which are 
 employed for being printed on the cloth : — 
 
 Colours to be applied by roller or cylinder, beginning with 1 
 the lightest and prucceuiiig to the heaviest shades . . < 
 
 Standard blue; parts 1 134 
 
 Acetate of iron liquor, at 7 Baume (sp.gr. i , 048), containing I , , , 
 
 700 grms. of gum per litre J 
 
 Gum-water, made up of 600 grms. to the litre 16 2$ 4 4 
 
 These shades may be varied in different ways, according to the desired pat- 
 tern. Since the indigo has a tendency to settle to the bottom of the vessel 
 from which it is supplied to the rollers, the liquid contained in that vessel has 
 to be stirred about now and then. If it happens that the pattern consists of 
 more than one blue, the machine-printer has to take care that — after the first 
 colour has been printed on and dried — he does not give too much colour to 
 the subsequent patterns, whereby the underlaying might become re-dissolved. 
 
INDIGO. 
 
 485 
 
 After printing on all the patterns, the cloth is kept for some time before under- 
 going other processes, in order to give time for the oxidation of the acetate of 
 iron, whereby the indigo is made to adhere more firmly, and the risk of its 
 becoming detached from the cloth, when the latter is immersed in the tanks, 
 is prevented. If this precaution is neglected, the shade becomes unequal. 
 Six tanks are employed in this process, — viz., two lime tanks, each 
 containing 12*5 kilos, of slaked lime; one copperas tank, at a strength of 
 7° Baume (1-048 sp. gr.) ; one tank containing caustic soda (sp. gr. noi) ; a 
 tank containing 500 grms. of strong sulphuric acid to each pailful of water ; 
 and, lastly, a tank with good fresh water. The goods are left for a quarter of an 
 hour in the first lime-water tank, care being taken to impart to the piece a slight 
 movement upwards and downwards ; next, the pieces are immersed in the 
 copperas tank, and left therein quietly for a quarter of an hour ; next, another 
 quarter of an hour in the second lime tank; and after that again a quarter of 
 an hour in the copperas, followed by a stay of five minutes in the caustic soda, 
 and half an hour in the dilute sulphuric acid, wherein the pieces are thoroughly 
 moved about and rinsed, and from this bath they are lastly transferred to the 
 clean water bath. After the passing of each piece through the lime-water 
 tanks, there is added to each of these 2 kilos, of freshly-slaked lime, while 
 50 kilos, of copperas are added to refresh the tank of this material after 
 ten pieces have been passed through it. The soda tank is kept in working 
 order by the addition of about 4 kilos, of caustic soda after the passage of 
 every five pieces. The tank containing the sulphuric acid is kept up by the 
 addition of 25 kilos, of acid after five pieces have been passed through, while, 
 moreover, the contents of this tank are thrown away as soon as it is dirty, a 
 freshly-filled supplementary tank being in readiness. 
 
 The experience of M. E. Schwartz, of Bale and Mulhouse, has proved that, 
 in order to make this method of working successful, the soda ought to be 
 thoroughly caustic, and kept up at the above-quoted strength, while it is also 
 essential that the copperas solution should be neutral, for which purpose the 
 solution is boiled with some clean scrap iron. After the goods have been 
 washed in the fresh-water tank, they are thoroughly washed in a current of 
 water, and next left over night in a very weak solution of sulphuric acid 
 (sp. gr. 1-007), in order thereby to remove the last traces of peroxide of iron. 
 The next morning the goods are again washed in cold water, and afterwards 
 passed through hot soap-water (temperature 50 ). 
 
 So-called China green is obtained by adding to the colour mixture some bi- 
 chloride and nitro-muriate of tin. The blue colour is fixed as above described, 
 but the goods are only left for two minutes in the soda and five minutes in the 
 acid tank. After washing, the pieces are dyed with quercitron. 
 
 Very dark shades cannot be obtained in the China blue style : it is a fast 
 colour, but expensive, on account of the time and labour it requires, especially 
 if carried out by the old process of dipping the goods attached on frames : by 
 the more modern method, described above, the vats (tanks) are supplied with 
 rollers, and the pieces passed through quickly ; time is saved, but it is at the 
 expense of the quality. 
 
 A resist for China blue, if required, maybe obtained by thickening a mixture 
 of sulphate of copper, acetate of lead, nitrate of copper, and lime-juice. 
 
 Fast blue and green colours are now produced upon calico (printed on) by a 
 
B88J8 BJB 
 
 BHBBBBBRBBBBBBBB 
 
 486 
 
 DYEING AND CALICO PRINTING. 
 
 process which in some respects is similar to, but in others different from, 
 China blue. This method consists essentially in the employment of a mixture 
 containing white indigo, along with another substance which serves to prevent 
 the too rapid oxidation of the white indigo. The compound is prepared as 
 follows : — The clear liquid of a strongly-made copperas vat is precipitated 
 with acidified solution of protochloride of tin ; the precipitate — indigotate of 
 hydrated protoxide of tin — is collected on filters made of a woollen fabric, 
 care being taken to protect the same as much as possible from contact of air. 
 A better preparation is obtained by heating a mixture of indigo, caustic soda, 
 and protochloride of tin, and precipitating it with hydrochloric acid : the pasty 
 mass thus obtained is thickened with gum, and frequently some tin-salt is also 
 added, to guard against every possible chance of oxidation before the mixture 
 is printed on to the cloth, while as soon as it is brought thereon the white 
 indigotin ought to be rendered soluble, to make it penetrate the fibre. This 
 last condition is readily obtained by passing the cloth at once into milk 
 of lime, which causes the immediate decomposition of the tin compound, the 
 lime combining with the colouring matter, the colour of which changes from 
 pale greyish-white to apple-green : the white indigo becomes indeed soluble 
 for a moment, but the presence of an excess of lime and of the thickener, 
 aided by the affinity of the fibre, prevent the colour from running. After 
 being withdrawn from the lime tank, the goods are washed in running water, 
 when the oxidation begins at once, and with it also the fixation of the dye- 
 ware, which becomes completed by the immersion of the goods in dilute 
 sulphuric acid. If to the colour, previous to use, a proto-salt of iron is added, 
 the oxide of which is precipitated in the lime tank, and if, instead of a simple, 
 acid bath, to such a bath be added yellow prussiate of potassa, the tint 
 of the indigo-blue, which by itself is always a bright, not deep, blue, is 
 very considerably deepened : instead of milk of lime a hot carbonate of soda 
 bath (sp. gr. 1/070) is employed, while instead of the sulphuric acid bath a 
 solution of bichromate of potassa is employed. The goods are left for five 
 minutes in the soda solution, and next rinsed for the same time in the second 
 solution ; after which the goods are washed and soaked for an hour in a 
 running stream. The cloth is next washed in hot soapsuds (70 ). 
 
 The fast green is obtained by adding to the indigotate of tin mixture any 
 suitable lead-salt (acetate commonly), which is first converted into oxide of 
 lead in the soda-bath, and next into sulphate, in the sulphuric acid bath. 
 This sulphate, being converted into a chromate by immersion in a solution 
 of bichromate of potassa, produces, with the blue of the indigo, a fast and 
 solid green. 
 
 Mr. Ward patented, in the year 1857, a method of employing indigo 
 which has obtained the name of glucose blue : the indigo, in the blue in- 
 soluble state, is mixed with a deoxidising material, preferably grape sugar or 
 glucose, and an alkali, soda or lime. This mixture, technically called the 
 colour, is applied cold to the cloth, and as soon as the goods leave the printing 
 machine, and without drying, they are passed into steam for about a minute. 
 The heat of the steam causes the reaction to take place, viz., the reduction of 
 the blue indigotin, which, being converted into white indigo, is in that state 
 dissolved by the alkali, and enabled to enter the fibre of the woven tissue, 
 which next requires washing and oxidising to bring up the blue colour. This 
 
INDIGO. 
 
 487 
 
 process does not appear to have been ever extensively carried out : the inten- 
 tion was that it should be applied in combination with madder, the mordant for 
 the latter being printed on at the same time. 
 
 A practical printer of great experience informs us that, setting aside the very 
 serious difficulty of steaming the goods before they are dry, whereby they are 
 exposed to many and serious accidents, the patentee's process, as published 
 in his specification, would have to be greatly modified before it could be prac- 
 tically applied. 
 
 M. E. Schlumberger has thoroughly investigated the subject of fixing indigo 
 by the so-called steaming process. He tried the following method: — Starting 
 with the knowledge that hydrated protoxide of tin reduces indigotin in the 
 cold, 'provided an alkali be present, he found that if, instead of the alkali, 
 cyanide of potassium be employed, the indigotin becomes only soluble (and of 
 course first reduced) during the steaming. The following mixture was tried : — 
 
 Indigo-paste (that is to say, indigo ground to pulp with) g ts 
 
 water), containing 20 per cent dry indigo > 
 
 Best cyanide of potassium (in cakes) 16 „ 
 
 Wet pasty hydrate of protoxide of tin 16 „ 
 
 Gum-water 52 ,, 
 
 This colour was found too expensive, and had the disadvantage of running 
 too readily, and could not be primed on simultaneously with any colours 
 giving off acids. It was never M. Schlumberger's intention to introduce this 
 colour on the large scale, but he found that it is capable of producing a most 
 magnificent fast green on being combined with cadmium yellow, prepared 
 according to M. Sacc, by means of a hyposulphite. This green resists, with- 
 out alteration, all the operations of madder dyeing. 
 
 When indigo-dyed calico is treated with a strong solution of caustic alkali, 
 the shades of colour become deeper, in consequence of the contraction the 
 tissue undergoes. 
 
 Indigo-dyed fabrics are recognised by their exhibiting a somewhat dull blue 
 colour, which resists the action of alkalies and of all acids which do not — by 
 acting as oxidising substances — destroy the colour. Among these acids the 
 nitric and chromic are the more common. Chlorine-water destroys the blue 
 colour of indigo. A freshly-made solution of zinc in sulphurous acid also 
 decolourises indigo. 
 
 When vatted tissue is immersed in a hot alkaline solution of protoxide of 
 tin it becomes decolourised, and the liquid turns blue on exposure to air. 
 When a vatted tissue is treated with the strongest fuming sulphuric acid the 
 fibre is destroyed, but if the liquid be diluted with water and filtered a blue 
 liquid will be obtained, exhibiting all the characteristics of the so-called 
 Saxon blue. 
 
 We have now to turn our attention to the application of the sulphuric deri- 
 vatives of indigo. Sulphindigotic and sulphopurpuric acids have no affinity 
 whatever for vegetable fibres, not even after they have been animalised or 
 albuminised. When even the so-called Saxon blue is occasionally applied to 
 cotton, after the excess of sulphuric acid has been saturated with either 
 acetate of lead or acetate of soda, whereby an equivalent proportion of acetic 
 acid is set free, and a preparation formed which is erroneously called acetate 
 

 488 DYEING AND CALICO PRINTING. 
 
 of indigo, this application takes only place for goods which are not to be 
 washed, the blue tinge imparted being not fixed at all. 
 
 Woollen and silk fibres do not behave in the same way with sulphindigotic 
 and sulphopurpuric acid : the direct affinity of sulphindigotic acid for animal 
 fibres is limited by certain conditions. When an excess of alkali is present 
 with this acid, or even when it is in the state of a neutral salt, it does not dye 
 wool, and this is readily explained by the fads above stated, as alkalies extract 
 the colour from wool, this process being made use of in the preparation of 
 so-called distilled blue. Although sulphindigotic acid unites directly with 
 wool, this property of the fibre is increased by the use of such mordants as 
 alumina and oxide cf tin. The dyeing with the substance just named should 
 always be executed in presence of an excess of acid, since the greater that 
 excess the greater the brilliancy of the hue, and the inure quickly the process 
 is finished. In former days the so-called Saxon blue, a solution of indigo in 
 sulphuric acid, diluted with water, was used ; now-a-days indigo carmine is 
 employed, while for printing on wool the so-called acetate of indigo above 
 mentioned is preferred. 
 
 The dyeing of the wool with indigo-carmine is very readily effected in a 
 warm bath, containing the carmine, alum, and sometimes also cream of tartar. 
 The alum enhances the solidity and fastness of this blue. 
 
 When the colour produced upon wool has been obtained by means of a sulph- 
 indigotic acid prepared with a large excess of fuming sulphuric acid (viz., 
 more than twelve times the weight of acid to that of indigo), such blue im- 
 perfectly resists treatment with alkalies, and even repeated washing with soap, 
 especially if during the dyeing operation heat be applied to the liquid in the 
 dye-beck. 
 
 Silk is dyed in a precisely similar manner, but it is first alumed. Sulph- 
 indigotic acid forms the ground colour for many mixed shades, as, for instance, 
 green, grey, violet, and black ; it is largely used in its modern form of indigo- 
 carmine, because it is so readily fixed. The printing operations are con- 
 ducted in a manner similar to that of dyeing: the solution of indigo-carmine 
 is slightly acidulated with oxalic acid, thickened with gum, alum being some- 
 times added in small quantity. Indigo-carmine is also largely employed for 
 the production of such colours as green, violet, grey, and it is added to a 
 number of others to alter their tone. 
 
 Indigo-blue, that is to say the indigo-carmine and sulphindigotic acid, is 
 readily detected upon wool or silk by the following tests: — A moderately strong 
 and tepid solution of crystalline carbonate of soda dissolves the blue colour, 
 the liquid becoming blue-coloured. Chlorine, nitric, and chromic acids destroy 
 the colour, as do also concentrated caustic soda, and a freshly-made solution 
 of zinc in sulphurous acid; on the other hand, this dye is not acted upon by 
 sulphuric, hydrochloric, and the stronger vegetable acids. According to 
 M. C. Kcechlin,* indigo-purple is violet when printed, but becomes blue after 
 having been steamed, and remains so, owing to the action of the sulphurous 
 acid which the woollen tissue retains from the brimstone vapours to which it 
 is exposed in bleaching. 
 
 We end this account of indigo with a brief statement of the mode employed 
 
 " Bulletin de la Societe Ind'istriellc e'e Mulhouse,'' vol. xxiv.. p. 335. 
 
INDIGO. 
 
 489 
 
 by the Chinese for dyeing blue. They designate all the plants they are 
 acquainted with, and which yield indigo, with the word Ian, while the blue 
 colour derived therefrom is called lan-tien; they employ the fresh leaves of at 
 least five different species of plants for dyeing blue in the following manner: 
 — The fabric to be dyed is thoroughly cleaned in pure water, and, after having 
 been dried, the cloth is steeped into a tepid warm bath, containing the leaves 
 of the Ian, to which some lime-juice is added. 
 
■■■■■ 
 
 ■ 
 
 BSBB 
 
 ■HBHB 
 
 (490) 
 
 CHAPTER VI. 
 
 BROWN AND BLACK COLOURING MATTERS. ASTRINGENTS. 
 
 "\ X 7E have now to treat of a class of proximate vegetable products which 
 
 * * are colourless by themselves, only yielding brown, grey, or black tints 
 under the influence of a special oxidation, or by the action of peculiar 
 mordants ; most of these substances belong to a class of organic compounds 
 as yet not thoroughly known. 
 
 Under the common name of cutch, catechu, gambier, cashew, and terra 
 Japonica there are met with in trade several kinds of vegetable extracts, 
 obtained by exhausting certain parts of plants, and evaporating the liquid 
 thus obtained to a suitable consistency. Several varieties of this substance 
 are distinguished in commerce according to the country of their production, the 
 species of plant they are derived from, and the form in which they are brought 
 into the market. The following are the chief varieties:* — Genuine catechu, 
 terra Japonica vera, is obtained from the internal portion of the wood of the 
 Acacia catechu, a tree belonging to the Leguminosae, section Mimosa;. This 
 tree, which attains a height of from 5 to 7 metres, is a native of Bengal and 
 other parts of Hindostan, and the islands of the Indian Archipelago. In order 
 to obtain the catechu the tree is cut down while it is fullest of juice, the soft 
 white coloured splint-wood is torn and cut away, and the internal portion of the 
 tree having been sawn into small sticks is boiled in water, in vessels made of 
 unglazed pottery; the liquid so obtained is concentrated first over an open 
 charcoal fire, and next placed for evaporation in the sun in shallow dishes 
 until the desired consistence has been obtained. The extract thus prepared 
 yields three varieties of brown catechu, viz. : — 
 
 a. The cutch on leaves, so-called Pegu catechu, met with in the trade in 
 
 cakes, weighing from 35 to 40 kiios., packed in large leaves; a dry, 
 glossy, brownish-red, or blackish-brown substance, of uniform texture 
 throughout, and of a sp. gr. 1*39. 
 
 b. Brown cutch run into moulds, made in the sand or clay, is a less pure 
 
 and inferior article. 
 
 c. Brown catechu, in cubic-shaped cakes, packed in coarse bags, weighing 
 
 from 35 to 40 kilos, per cake; this kind of cutch is imported from 
 Java, Singapore, Pegu (via Calcutta), chiefly into the ports of London, 
 Amsterdam, and Hamburg. 
 The Bengal cutch is obtained by a process similar to that just described, 
 
 * Guibourt, "Journ.de Pharmacie," (3), xi.,24, 260, 360; xii., 37, 183,267. Girardin, " Letons 
 de Chimie," 4th edition, ii., p. 636. 
 
KINO. 
 
 491 
 
 from the fruit of the areca palm, Areca catechu, a tree widely spread over the 
 tropic portion of Asia. This kind of cutch is met with in commerce in the 
 shape of cubical blocks, each side measuring from 3 to 4 centimetres. 
 The colour of this substance is brighter than that of the cutch which is 
 shipped at Bombay (the mixed produce of the Acacia catechu and areca nut), 
 the colour being chocolate-brown, with deeper and lighter coloured bands 
 alternating. This substance exhibits a dull appearance when broken, and is 
 very dry and sandy, although sand is not necessarily present ; the sp. gr. is r28. 
 
 Yellow cutch, cubical cutch, or gambir, is the extract obtained from the 
 leaves of the Uncaria gambir and Uncaria acida shrubs, belonging to the 
 family of the Rubiacese, tribe of the Cinchonas (Roxburg), abundantly met 
 with in Sumatra, Malacca, Pulo-Penang, Singapore, the Moluccas, and the 
 Sunda Islands. This kind of cutch, known very generally as gambir, occurs 
 in commerce in the shape of thick flat cakes, externally brown, internally 
 bright yellow, fracture dull, taste bitter and astringent. 
 
 Kino or gum kino, the produce of the Butea frondosa (Leguminosae) and 
 the Ptericarpus marsupium, also of some other plants, is a deep blackish brown, 
 glossy-looking substance, of an astringent and bitter taste, only used in 
 medicine. The following preparation of kino might be worthy of practical 
 investigation : — Boil powdered kino for some time in water. On cooling the 
 concentrated solution a substance separates out, and is collected upon a filter. 
 It is then boiled in concentrated hydrochloric acid, when it dissolves with an 
 intense violet colour. This is allowed to cool, and then diluted with water, 
 when a rich dark brown powder is deposited, and carefully washed. It is 
 soluble in alcohol with a violet-red, and in hot acetic acid with a poppy-red. 
 The latter solution is said to give a pale rose shade on stuffs mordanted with 
 salts of iron. It dyes wool and cotton moderately, and silk very finely. 
 With tin mordants it yields rich cherry and scarlet shades; alumina com- 
 pounds are unfavourable to the colour. 
 
 As regards their chemical composition, the above-named substances do not 
 differ much from each other. By qualitative tests there have been found in 
 these substances the following matters : — 
 
 1. A peculiar kind of tannin, soluble in cold water, precipitated by gelatin, 
 
 and also by salts of the peroxide of iron with a greyish-green colour; not 
 precipitated by a solution of tartar emetic. This rather ill-defined 
 body, whose properties and composition are not very well known, is 
 termed catechutannic acid. 
 
 2. A colourless, crystallisable principle, called catechuin or catechuic acid, 
 
 which is the main cause of the tinctorial properties of catechu. 
 
 3. Brown so-called extractive substance, present in greater or less quantity, 
 
 and due to the alteration of the two foregoing matters. 
 Catechutannic acid is an amorphous, colourless substance, soluble in cold 
 water, as well as in alcohol and ether; its taste is astringent. It may be 
 prepared in an impure state by adding to a cold-made and concentrated 
 aqueous solution of catechu concentrated sulphuric acid ; the precipitate thus 
 produced is washed with water slightly acidulated with sulphuric acid, and 
 next re-dissolved in water; this solution is treated with carbonate of lead, 
 filtered, and concentrated in vacuo. Another mode of preparation consists in 
 treating catechu, coarsely powdered and put in a displacement apparatus, 
 
IBJHmmam 0I0U hhhum MMM 
 
 ■ 
 
 ^^^BB fkaEEB BEE 
 
 IHflffl 
 
 492 
 
 DYEING AND CALICO PRINTING. 
 
 with ether; the solution thus obtained yields, on evaporation in vacuo, a porous 
 yellowish mass. 
 
 According to Dr. Delfts,* the solution of catechutannic acid becomes, when 
 exposed to air, deep red, and yields then catechuin ; this latter assertion is 
 denied by M. Neubauer,! who states that the oxidation of the catechuin caused 
 by exposure of its solution to air results in the formation of a tannin pre- 
 cipitable by gelatin. 
 
 Alkalies favour the oxidation of the tannin of catechu when in aqueous 
 solution; catechutannic acid does not yield glucose when it is boiled with 
 dilute sulphuric acid, and differs in that respect from ordinary tannin, viz., 
 that of nut-galls. 
 
 According to the researches of Dr. Davy and Dr. Nees von Esenbeck, the 
 quantity per cent of catechutannic acid found in the undermentioned varieties 
 of catechu amounts to : — Bombay cutch, 54-4 ; Bengal, 48*2 ; Gambir, 36 to 40. 
 Catechuin, + when pure, is a silky crystalline substance, with a peculiar 
 mother-of-pearl-like appearance, containing water of crystallisation, driven 
 off at 100°; fusing at 217 , decomposed at a higher temperature, and thereby 
 converted into a volatile product, pyrocatechuic or oxyphenic acid, C6Hg0 2 . 
 Catechuin is almost devoid of taste, neutral to test-paper; soluble in 1133 
 parts of water at 17 , and in from 2 to 3 parts of boiling water, but crystallising 
 from that solution on cooling in acicular-shaped crystals; soluble in from 
 5 to 6 parts of cold, and from 2 to 3 parts of hot, alcohol ; soluble in 120 
 parts of cold, and from 7 to 8 parts of boiling, ether. 
 
 Catechuin is best prepared from the yellow catechu met with in cubical- 
 shaped cakes ; this substance, first reduced to powder, is next exhausted with 
 cold water for the purpose of eliminating the tannin ; the residue is then 
 treated with about eight times its weight of boiling water; the catechuin 
 separates from this solution after cooling, and the substance is then pressed 
 between cloth to separate the mother-liquor ; thereupon the crystalline mass 
 is re-dissolved in water, and this solution precipitated with subacetate of lead. 
 Care is taken to add this reagent drop by drop, and to stop further addition as 
 soon as a white precipitate begins to appear; the fluid is then filtered, and 
 the filtrate precipitated with the above reagent. The deposit thus thrown down 
 is washed with some hot distilled water, and next suspended in boiling 
 water, and decomposed by means of sulphuretted hydrogen. The liquid is 
 again filtered while yet hot, and on cooling deposits pure catechuin. This 
 substance consists, in the anhydrous state of 61-4 per cent of carbon, and 
 5 per cent of hydrogen, the remainder being oxygen; in the hydrated state it 
 contains per cent — Carbon, 52-06; hydrogen, 6-o. 
 
 In consequence of the importance of catechuin as a dye-stuff, we have to 
 enter into some details here on the different opinions held in reference to the 
 composition of this material. M. Zwenger proposes the formula C 20 UisOs ; 
 M. Neubauer prefers C 17 Hi$0 7 . According to Dr. Rtrecker, catechuin is a 
 
 * " Jahresb. fiir Prakt. Pharm.," xii., 162. 
 
 t Neubauer, " Ann. der Chem. und Pharm.," xcvi., 337. 
 
 t The following are the most important papers on this subjett, published in the periodicals : 
 — Nees von Esenbeck, " Ann. der Chem. und Pharm.," i., 343. Zwenger, "Ann. der Chem. 
 und Pharm." xxxvii.,320. Hagen, " Ann. der Chem. und Pharm. ,"xxxvii., 336. Delfts, loc.cit. 
 Neubauer, loc. lit. Van Delben and Kraut, "Ann. der Chem. und Pharn..," cxiviii., 285. 
 Schiitzenberger and Rack, "Bullet. Soc. Chimiq. de Paris," July, 1865, p. 5. 
 
CATECHU. 
 
 493 
 
 mixture of two very closely allied homologous substances, which can be 
 separated from each other with great difficulty, viz., deutocatechuic acid, 
 CieHxeOs, and tritocatechuic acid, dsHaoOs- Kraut and V. Delben, again, 
 do not share Dr. Strecker's opinion, and propose for catechuin the formula 
 Ci 2 H I2 5 + 2H>0 ; Hlasiwetz and Malin prefer C^H^Os ; and the following 
 formula?, Ci O H I0 O 4 and C 22 H 2 20 g , also agree with the results of the elementary 
 analysis. It is clear, therefore, that the true formula for catechuin can only 
 be settled by deduction from the products derived from it, and to these 
 derivatives we have now to turn our attention. 
 
 When catechuin is boiled with dilute sulphuric acid, with exclusion as 
 much as possible of air, or boiled with alcohol, previously saturated with 
 hydrochloric acid gas, it is converted into a brown amorphous body, insoluble 
 in water and alcohol, catechuretin, which appears to be formed by dehydration 
 from catechuin; the formula; assigned to catechuretin are, according to 
 M. Neubauer, Ci 7 H I4 7 ; Kraut and V. Delben, Ci 2 H I0 4 ; Hlasiwetz, 
 Ci 9 H I4 06 = C 1 gH I 803 (catechuin) minus 2H 2 0, also C^H^C^. 
 
 When catechuin is fused with hydrate of potassa it is split up into phloro- 
 glucin and protocatechuic acid, a reaction which Hlasiwetz represents by — 
 C 19 H l8 08 + 3 = C 7 H60 4 + 2C6H603. 
 
 Proto- Phloroglucin. 
 
 catecbuic 
 acid. 
 
 Catechuin yields with bromine-water an insoluble reddish matter named 
 bromo-catechuretin, the formula of which is, according to Kraut and 
 V. Delben, C I2 Br 4 Hc0 4 , or Ci^HsBtqOq, according to Hlasiwetz and Malin. 
 Chloride of benzoyl yields, when heated to igo° with catechuin, two new 
 products, one of which, soluble in alcohol, appears to be monobenzoic 
 catechuin, while the other body, insoluble in alcohol, seems to be benzoic 
 catechuretin. When catechuin is heated to 100° with hydriodic acid, the 
 organic substance is deoxidised and transformed into a yellow elastic 
 granular body, insoluble in water, alcohol, ether, and acetic acid; containing 
 in ioo parts 63-90 carbon, and 5-0 of hydrogen, the remainder being oxygen. 
 A solution of catechuin in acetic acid yields, upon the addition of pulverised 
 binoxide of barium a white body, insoluble in boiling water, soluble in acetic 
 acid, and precipitated from that solution in a crystalline state upon the 
 addition of water ; the percentage composition of this body is — Carbon, 58*0 ; 
 hydrogen, 4*70; the rest being oxygen. Catechuin is converted by bichromate 
 of potassa as well as by dilute and hot nitric acid into a brown insoluble 
 amorphous body ; that resulting from the action of bichromate of potassa 
 consists, in 100 parts, of— Carbon, 58-07; hydrogen, 3-42; the rest being 
 oxygen. This brown matter is readily soluble in dilute nitric acid, the result 
 being the giving off of carbonic and the formation of oxalic acid. With concen- 
 trated nitric acid, catechuin yields a product analogous to picric acid. 
 Catechuin absorbs oxygen very rapidly and completely in presence of alkalies, 
 and such solutions become the.iby first red, then brown, and contain in that 
 condition some brown, ill-defined substances known as rubinic and japonic 
 acids. Catechuin undergoes the same alteration when its aqueous solution is 
 exposed to air, but the action is more slow ; it is this reaction and property of 
 catechuin, viz., its readily yielding by oxidation brown insoluble matters, which 
 is the basis of its application in dyeing and printing. 
 
' 
 
 494 
 
 DYEING AND CALICO PRINTING. 
 
 When the crude catechu of commerce is exposed to a temperature of ioo°, 
 it fuses, becomes transparent, losing from 4 to 5 per cent of its weight of 
 water ; on ignition in a platinum crucible, there is left from 3 to 4 per cent of 
 mineral incombustible matter. Catechu being an extract, is liable to be 
 adulterated with various other substances, among which sand, clay, ochre, 
 dried blood, sugar, and coarse starch are the chief; the careful examination 
 of the physical and organoleptical characters of the substance, as well as of 
 the quantity and nature of the residues insoluble in water and alcohol, the 
 quantity and nature of the ash, may give some idea of the purity of the 
 sample, which ought to be entirely soluble in hot water, and then give a brown, 
 not blackish, solution. It ought not to be totally soluble in cold water, for that 
 is an indication of heating and partial decomposition. The hot, watery 
 solution should, on cooling, deposit a portion of the catechu in a fine, 
 granular state. The only reliable test for the quality of catechu is to make 
 some colour from it, or to dye up samples from it in comparison with an equal 
 weight of a known sample. 
 
 Catechu is employed* in medicine, for tanning skins, and for dyeing. 
 For this latter purpose, catechu has been used in India from time immemorial. 
 It was not employed in Europe until in 1806, when MM. Schaeppler and 
 Hartmann first used it as a brown colour in conjunction with madder work. 
 Their method of application described by Dr. Dingier f was, however, not 
 adopted ; and catechu was hardly used for dyeing or printing to any extent 
 until 1829, when M. Barbet, of Jouy, re-introduced it. Catechu yields, 
 when boiled with water, a turbid decoction ; the infusion above named is 
 commonly also turbid : but when there are added to the water 8 parts of 
 vinegar (sp. gr. 1*007, containing 4 per cent of anhydrous acetic acid), and the 
 boiling continued for some time, a rather clear solution is obtained. Catechu 
 is also readily soluble in caustic soda lye of moderate strength. An aqueous 
 decoction of catechu yields, with calico mordanted with alum, a deep 
 yellow, and with iron mordants an olive. This shade becomes brighter 
 and far more beautiful by the addition of glue; while by being passed through 
 a solution of bichromate of potassa, the shades of both mordants are made 
 brown. When a small quantity of acetate of copper is added to the decoction 
 of catechu, it yields with alumed calico a kind of oak-brown colour, and with 
 an iron mordant a deep cinnamon-brown. If the solution or decoction of 
 catechu is acted upon by a solution of bichromate of potassa previous to 
 being fixed upon the cloth, it becomes unsuitable for use. 
 
 Generally speaking, catechu is of no use for dyeing purposes unless the 
 oxidation takes place upon the tissue itself; indeed, the colourable matter 
 present in cutch (the catechuin) is only soluble and capable of penetrating 
 into the fibres as long as it is not oxidised, for when once the oxidation 
 of catechuin has taken place, it becomes totally inert and insoluble, and is 
 then only capable of being mechanically fixed. The processes by which 
 colours derived from catechu are obtained are based upon the following prin- 
 ciples: — The catechuin is applied in solution on the fibre which is penetrated 
 
 * "Bulletin de la Societe Industrielle de Mulhouse," vol. xii., pp. 354, 373; vol. xiii., p. 291; 
 vol. xiv., p. 197. 
 
 t Dingler's " Polyt. Journ.," ii., No. I, 1815. This mixture is printed on the calico, is next 
 steamed, and afterwards passed through a solution of bichromate of potassa. 
 
CATECHU. 
 
 495 
 
 by it, and the woven tissue is next placed in such a condition as is most 
 expedient for the oxidation, and, consequently, transformation, of the colour- 
 able principle into a brown insoluble and firmly-adhering substance. The 
 oxidation can be effected by : — 
 
 i. Exposure of the tissue to air, — a rather slow process, — with the simul- 
 taneous application of steam. 
 
 2. The transformation is greatly accelerated and aided by the introduction 
 
 into the colour mixture of such materials as are capable of acting as 
 oxidating substances either more slowly or more rapidly if steam is 
 applied ; such substances are in this case salts of copper. 
 
 3. The oxidation is greatly accelerated by passing the tissue after the 
 
 catechuin — that is to say, the catechu, since as yet pure catechuin is 
 not commercially prepared in a state of chemical purity — has been 
 printed on, into an alkaline solution, whereby the affinity of the 
 catechuin for oxygen is greatly increased. 
 
 4. By passing the goods through a solution of bichromate of potassa. 
 
 5. Lastly, a combination is made of two of these processes, viz., steaming 
 
 and passing into bichromate, or also ageing and steaming. 
 
 It has been suggested to wash powdered catechu in cold water, which 
 dissolves the tannin, leaving catechuin untouched. This latter substance, 
 being soluble in hot water, is then fit for use. Sacc states that catechu, when 
 treated with sulphuric acid, is decomposed chiefly into glucose and a brown 
 resin, which, on being dissolved either in moderately strong sulphuric acid, or 
 in an alkaline solution, assumes a beautiful purple colour remarkable for its 
 stability. The brown resin is probably employed by some dyers and printers 
 in place of catechu. Of course, if catechu alone is used, the manufacturer 
 applies the most rapid and complete method, which is undoubtedly the 
 passage through bichromate ; but if it is mixed up with other colours, it is 
 requisite to adopt the process which suits the case, so as to have the desired 
 effect upon the catechu, yet not to injure or alter the other colours. 
 
 The natural tint which catechu produces is modified by the introduction or 
 addition of divers metallic salts, such as those of iron, manganese, and others, 
 among which the salts of copper play an important part, chiefly, however, for the 
 fixing of catechu. This point has been purposely investigated by MM.C. Kcech- 
 lin and Mathieu-Plessy.* As a result from their experiments, confirmed by 
 those of M. H. Schlumberger, we learn that sal-ammoniac has a specific 
 influence in promoting the oxidation of the colourable matter of cutch by the 
 oxy-sahs of copper ; indeed the oldest receipts for the employment of catechu, 
 given by Schaeppler and Hartmann in 1806, and by M. Esslingerat Jouy in 
 1829, recommend the mixing of a salt of copper and sal-ammoniac as a means 
 of fixing the dye upon cloth. 
 
 The mode of action of the sal-ammoniac is differently explained. Ac- 
 cording to M. Persoz, it acts by its tendency to form double salts, thereby 
 keeping in solution divers salts and oxides ; according to Schwartz, the sal- 
 ammoniac should serve to prevent the catechu from combining with gum. 
 The latter idea is of little value, the less as the same mixture is usefully 
 employed in other instances for the very purpose of causing oxidation, as in the 
 
 * " Bulletin de la Societe Industrielle de Mulhouse," vol. xxii., p. 311 and following. 
 
sflr^ 
 
 y 'VVv'vV ;V- s' V * VtV X TV'?'-" V". \ : "' V'. V '? H V VV-"'.:*''. 1 
 
 ■ 
 
 496 DYEING AND CALICO PRINTING. 
 
 case of red woods, logwood, and aniline black. M. Koechlin thinks that the 
 sal-ammoniac acts by double decomposition, causing the formation of chloride 
 of copper, which in its turn is converted into protochloride by the catechuin, 
 and together kept in solution by the sal-ammoniac. The last-named salt, by 
 becoming again oxidised by contact of air, is again capable of acting upon a 
 fresh portion of organic matter : the sal-ammoniac cannot be replaced by any 
 other ammoniacal salt; and although M. Koechlin states that chloride of 
 sodium acts in a similar manner, this is denied by Schluniberger, who pur- 
 posely tried it experimentally. Recently it has been found that sulphmet of 
 copper can be advantageously used instead of the oxy-salts of that metal. 
 
 About the year 1832 the fixation of catch by means of the bichromate was 
 first applied by MM. Koechlin Freres, at Mulhouse. The deeper-coloured 
 goods are steamed before they are padded in the chromate solution, which 
 should be sufficiently strong to prevent the colour running, while the solution 
 is made warm. For bright-coloured goods the steaming is simply replaced by 
 an exposure to air. 
 
 The oxidation of the catechuin in the bichromate solution is instantaneous, 
 producing at once a brown colour; the chromate solution itself is reduced to 
 sesquioxide. 
 
 M. Schluniberger thinks that there is a kind of chrome-lake formed along 
 with the oxidised catechu, the oxide entering into combination and modifying 
 the colour produced. M. Heckmann* states that some of the oxide is only 
 mechanically mixed with the colour, and this is the generally admitted 
 opinion. 
 
 Oxidation by means of passing the goods through milk of lime is another 
 process, which, although less satisfactory, is employed whenever catechu is 
 printed on along with such colours as are fixed by means of lime, as is the 
 case with fast blue. The presence of an alkali or of an alkaline earth aids 
 the absorption of oxygen by the catechuin, but this operation is usually 
 carried out along with the employment of salts of copper and of sal-ammoniac, 
 and also with the ageing process. 
 
 Catechu serves for dyeing bright and deep brown, fawn, drab, and wood 
 colours, and also for printing. Catechu colours are often associated with 
 garancin colours, by mordanting" with alumina and dyeing up in garancin and 
 cutch, the hue produced is modified, and turned to brownish-red. 
 
 The cutch dyes are remarkable on account of their fastness ; they resist 
 alkalies, soap, acids, and even chlorine, in a high degree, and do not admit of 
 the application of the discharge process. 
 
 Catechu is used either in aqueous decoction or hot infusion, or vinegar or 
 acetic acid are mixed therewith, or a solution in caustic soda is used. The 
 following are instances of the mode of mixing the ingredients : — 
 
 Catechu 6 kilos. 
 
 Soda-lye, at io° Baume (sp. gr. 1*070, containing about - ) 
 
 7-75 per cent of dry caustic soda) j litres. 
 
 Water 8 ,, 
 
 Thicken with gum ; steam, and next oxidise by passing through a bath of 
 bichromate (containing from 5 to 7 grms. of that salt to the litre of water), at 
 a temperature of from 75° to 88° for twc minutes. 
 
 * " Bulletin dc la Societe Industrielle de Mulhouse," vol. xiv., pp. 186 and 197. 
 
CA TECHU. 497 
 
 Catechu 6 kilos. 
 
 Acetic acid, at 7° Baume (sp. err. 1-048, containing about) ... 
 
 ,,,.., s 12 litres. 
 
 30 per cent of anhydrous acetic acid, at 15 ) . . . . J 
 
 Water 4 ,, 
 
 Thicken with gum ; steam, and pass through the bichromate bath. 
 
 Catechu 10 kilos. 
 
 Pyroligneous acid 20 litres. 
 
 Solution of acetate of lime (sp. gr. 1-048) 5 ,, 
 
 This ingredient can only act as a hygroscopic substance. 
 
 Solution of acetate of manganese (sp. gr. i , 246).. .. 5 ,, 
 This material modifies the hue or tint. 
 
 Gum 7-5 kilos. 
 
 Again steaming, and oxidation by means of the bichromate. 
 
 Catechu 3 kilos. 
 
 Pyroligneous acid 6 litres. 
 
 Sal-ammoniac 360 grms. 
 
 Verdigris. 31 „ 
 
 Gum-water, made up with 700 grms. to the litre . . . . 6 litres. 
 
 Acetate of lime solution 1-5 „ 
 
 Fabrics dyed or printed with this mixture are not steamed, and not passed 
 through a chromate bath, but are first aged, and next passed through lime- 
 water (milk of lime). 
 
 Catechu Mixture for Madder Style. 
 
 Catechu 14 kilos. 
 
 Water 18 litres. 
 
 Sal-ammonia 5 kilos. 
 
 Acetate of copper 3375 kilos. 
 
 Acetic acid (sp. gr. 1-048, containing about 30 per) ... 
 
 , , , ., v r *3 htres. 
 
 cent of anhydrous acid at 15 ) 1 
 
 Solution of acetate of lime 9 litres. 
 
 Gum 15 kilos. 
 
 Pyrolignite of alumina in solution (sp. gr. 1-070) .. 1 litre. 
 
 After having been printed on the tissue, along with or next to the mordant, 
 this mixture is fixed by ageing, next passed through the dung-bath, and after- 
 wards dyed in madder. Where it is desired to have a catechu-dyed ground 
 four different processes may be employed : — 
 
 1. A mixture of an acetic acid decoction of catechu and pyrolignite of iron 
 is printed on and left exposed to air for twenty-four hours, after which time 
 it is bichromated ; the decoction is made up of — 
 
 Yellow catechu roo grms. 
 
 Water 2 litres. 
 
 Acetic acid (sp. gr. 1-056, containing 37 per cent) 
 
 anhydrous acid at 15 ) J 
 
 Gum 1 kilo. 
 
 To every 10 litres of this standard mixture 1 litre of pyrolignite of iron 
 (sp. gr. 1-070) is taken. When the colour is to be lighter 4 litres of gum 
 
 2 K 
 

 498 DYEING AND CALICO PRINTING. 
 
 water are added to dilute the mixture. After this mixture has been printed 
 on, the tissue is exposed for twenty-four hours to air, and is next passed 
 through a bath of bichromate, consisting of 5 grms. of the salt per litre of 
 water, and kept at a temperature of 94°, this operation being carried on in a 
 tank provided with rollers, so that the tissue is only in actual contact with the 
 liquid for about two minutes ; the goods are next washed for half an hour in 
 the washing machine in cold water. 
 
 2. Print on a decoction of catechu, leaving out the iron preparation, and 
 otherwise proceeding as above directed. 
 
 3. Print on the following Nankeen mordant,* consisting of — Copperas, 
 2 kilos.; acetate of lead, 1-5 kilos.; water, 2 litres. After the separation of 
 the sulphate of lead there is added for every 2 litres of this preparation 
 1*25 kilos, of British gum; the mixture then forms the standard colour, which, 
 according to requirements, is diluted with from 7 to 45 litres of British gum 
 solution. After having printed this mordant on the pieces they are aged for 
 twenty-four hours, and next passed through a silicate of soda bath, and, after 
 having been washed, the following catechu mixture is used as dye (the mixture 
 to serve for 50 metres) : — 
 
 Water 150 litres. 
 
 Decoction of catechu, containing 180 grms. to the litre 3 ,, 
 The temperature is gradually raised from 19 to 80°; after passing through 
 the bichromate the goods are washed in the machine and dried. 
 
 4. Print on a red liquor, which is fixed as there directed, dye in cutch, and 
 bichromatise. 
 
 For so-called mode grounds the following processes are employed: — 
 
 1. A mixture of cutch and pyrolignite of iron is printed on, and the tissue 
 
 next passed through a bichromate bath at the temperature of 56 . 
 
 2. The above-named Nankeen mordant is printed on first, and the fabric 
 
 next dyed in cutch also, as above specified, but the bichromate bath is 
 not employed. 
 
 3. A mixture of catechu decoction and Nankeen mordant is printed on first, 
 
 after which the fabric is aged for twenty-four hours, then exposed in a 
 
 steam chest at a pressure of 30 lbs. to the square inch (2 atmospheres) 
 
 for half an hour, and, lastly, washed and dried. 
 
 The same processes as those just specified are also employed for silk and 
 
 wool, but the use of catechu for these animal fibres is limited to being an 
 
 adjunct in some kinds of black dyeing. The browns which it j'ields are not so 
 
 desirable as those which can be obtained from a mixture of other colouring 
 
 matters and mordants. 
 
 Catechu is largely used in woollen printing (flannels and linseys) for ob- 
 taining dark shades of drab, of a red or brownish tinge, in combination with 
 
 * The name of Nankeen colour is usually given to the shade of buff obtained from iron 
 salts; in piece dyeing the cloth is run through copperas liquor, and then through lime-water; 
 for lighter shades nitrate of iron is preferable ; the colour may be softened both in appearance 
 and to the feel by finally working in warm soap-suds; annatto gives yellower Nankeen shades, 
 which may be combined with chrome yellow. Nankeen has obtained its name from the 
 Chinese city Nankin, whence a peculiar buff-coloured silk and cotton were first imported 
 into Europe. The Nankeen dyes with cutch are fast, but a great many inferior imitations 
 exist, and have been treated of in our foregoing pages under various headings. 
 
GALLS. 
 
 499 
 
 other colouring matters to modify the shade. Cutch yields a variety of brown 
 shades; also olive, wood-colour, and so-called bronze hues. The applications 
 of catechu are, however, still limited, and it is doubtless capable of many 
 more valuable applications than it has yet received. 
 
 True Astringents. 
 We have now to turn our attention to some substances which are strictly 
 astringents rather than dyes, and among these, in the first place, nut-galls. 
 These are globular-shaped, dirty, brownish substances, having the size of 
 small marbles, the morbid excrescences produced by the punctures of an insect 
 called Cynips Galla-tinctorice, belonging to the order Hymenoptera, upon the 
 leaves and young twigs of several kinds of oak trees, and more especially 
 those of Quercus infectoria, a small tree indigenous to India, Persia, Syria, the 
 Levant, and some parts of Greece, and other portions of the South of Europe. 
 The fully developed nut-gall contains a central cavity, wherein, on breaking it 
 open, will be found the larva of the insect. The galls are generally gathered 
 and collected before the larva has had time to become fully developed, and 
 therefore before it has consumed a portion of the internal layers of the 
 envelope by which it is enclosed, and escaped as a mature insect. This fact 
 is mentioned here because it bears upon the qualities of nut-galls as distin- 
 guished in commerce ; the non-perforated nuts, which are heavier than the 
 perforated, are known by the name of blue, black, or true nuts ; the other kind 
 are known as white or false nuts. The former are deemed preferable to the 
 latter, and command a higher price, but in the English market both kinds are 
 frequently found mixed together in the same parcel : the size and shape of the 
 nut-galls vary, the latter being spheroidal or ovoid, and the former ranging 
 from that of a pea to a diameter of from i to 2 centimetres. The exterior 
 surface is more or less smooth, and with slight conical excrescences of various 
 size. The chief commercial varieties are — 
 
 Aleppo Galls, or Turkey Galls. — Imported from Aleppo and Smyrna, whither 
 they are brought from the interior of the country. This variety is 
 subdivided into — Heavy black galls, of a blackish-grey colour with 
 whitish excrescences; greenish or bluish galls, with white excres- 
 cences ; whitish-yellow wrinkled and pierced (false galls). 
 Morea Galls. — Of the size of hazel nuts, brown, irregular-shaped, and often 
 
 quite hollow. 
 Smyrna Galls. — Greenish-black, greyish-black, and whitish-yellow ; are a 
 
 less esteemed quality than the Aleppo galls. 
 So-called Marmorinc Galls. — Small, round, iron-grey coloured nuts, having 
 
 a smooth surface. 
 Istria Galls. — Very small, light, pale yellow-coloured. 
 French Galls. — Very small and light, smooth-surfaced, pale yellow- 
 coloured. 
 Piedmontese Galls, known as " knoppern," are irregular-shaped excres- 
 cences developed upon the glands (acorns) of the Quercus pcdunculata, 
 the consequence of the puncture of an insect, the Cynips Quercus- 
 calycis, also belonging to the order Hymenoptera. This kind of nut- 
 gall is gathered in Hungary, Dalmatia, Roumania, Styria, Piedmont, 
 and other countries. 
 
 2 k 2 
 
mBHBEB BEHeHB 
 
 500 
 
 DYEING AND CALICO PRINTING. 
 
 China Nut-galls. — More or less spherical in shape and irregular in size, 
 externally provided with conical points, internally hollow; average 
 size that of a Barcelona nut. This kind of gall is formed upon a 
 species of sumac, and is highly valued on account of its large per- 
 centage of tannic acid. 
 Valonia Nuts, sometimes known as Levant Nut-galls, are imported into 
 Europe from Greece, Southern Italy, Smyrna, and other parts of 
 Asiatic Turkey ; the acorn-cup of a species of oak botanically known 
 as Querciis agilops. These cups have the shape of flowers, the acorn 
 being in the centre, and are readily detached from the fruit by a kind of 
 fermentation which the substance undergoes when laid up in heaps : 
 the acorn having fallen out, the flower-like cup is dried, and is then 
 fit for the market. 
 Divi-divi, livi-divi, or libi-divi, is now one of the most important astringents 
 in the market. It consists of the pods of Casalpinia coriaria, a small tree 
 found in the province of Maracaibo, and in other parts of South America. 
 The pods are of different shades of brown, sometimes nearly black; they are 
 about 3 inches long and 1 inch broad, and are usually warped, twisted, or even 
 doubled up. The best pods are thick and fleshy, and of a pale colour. Those 
 which are very dark, with black spots and blotches, have probably been 
 gathered in a damp state, or have been subsequently exposed to moisture, 
 which greatly reduces their value. The amount of tannin in divi-divi is 
 greater than in sumac, or even myrobalans, but it is in the first-mentioned 
 body accompanied by a peculiar colouring principle, which limits the applica- 
 tions of this ware. It is very largely used in producing a black upon the 
 cotton warps of mixed goods. Divi-divi has another defect : it is of a glutinous 
 or adhesive nature, whence fragments of the ground pods are apt to cling to 
 the mordanted tissues, and when washed away are found to have played the 
 part of a resist, and protected certain portions of the goods from the action of 
 the tannin. Consequently, when the dyeing operations are completed the 
 cloth appears speckled. Hence it is better to extract the ware with water, and 
 allow only the clear liquor to come in contact with the goods. Divi-divi is 
 generally the cheapest astringent. 
 
 Myrobalans, otherwise called myrabolans, or myrabolams, are the fruit of 
 Terminalia Chcbula, a tree common in some parts of India. In shape and 
 size myrobalans somewhat resemble shrivelled plums. They are of a pale 
 buff colour, consisting of a dry pulp, varying in thickness, and enclosing a 
 stone-like kernel, which contains no tannin, and forms from 23 to 52 per cent 
 of the whole weight. The moisture present in the nuts, as found in commerce, 
 varies from 3 to 7 per cent, and the amount of ash left on incineration is about 
 10 per cent. The tannic acid is mainly present in the pulp. Good unground 
 myrobalans should be pale, plump, free from dark blotches and from worm- 
 holes. They should be hard and firm, ringing like fragments of earthenware 
 when shaken together, and if crushed with a hammer yielding a dry, pale 
 powder, mixed with hard irregular fragments. If they can be crushed to a 
 dark-coloured dust between the fingers, or if they work out into a paste under 
 the pestle, they are of poor quality. Ground myrobalans should form a pale 
 buff powder, dry, astringent to the taste, but free from a saline flavour or from 
 intense bitterness. If moistened and rubbed in the hand, they should form a 
 very tenacious paste. 
 
ASTRINGENTS. 
 
 50i 
 
 The nuts, when bought whole, are often found mixed with earth, sand, 
 mica, nux vomica, betel-nuts, &c. 
 
 Ground myrobalans are sometimes contaminated with divi-divi, spoiled 
 sumac, and wild galls. To detect such impurities a little of the powder is 
 thinly sprinkled over a sheet of white paper, and examined with a lens. If 
 divi-divi has been added, fragments of its bright brown flat seeds are sure to 
 be found. The outer skin of a myrobalan may occasionally resemble a divi- 
 seed in colour, but the minutest portion of the former shows a wrinkled 
 surface, whilst divi-seeds are smooth. The leaf-stalks and midribs of sumac 
 may also be distinguished, by the aid of a lens, from the torn and jagged fibre 
 of the myrobalan. 
 
 Myrobalans, being cheaper than galls and stronger than sumac, have, to a 
 very great extent, superseded both. Along with salts of iron, they dye cotton 
 a fuller black than can be obtained with sumac. They are likewise preferred 
 to sumac for fixing the coal-tar colours upon cotton, owing possibly to the fact 
 that they contain, along with tannin, certain oily and glutinous matters. 
 Gall-nuts and commercial tannin are, however, still preferable. 
 
 M. Muratore, of Algeria, has recently made a series of experiments with 
 the leaves and fruit of Pistacia lentiscus, a tree found in various parts of 
 Africa. He finds that the decoction gives, with salts of iron, good solid blacks 
 upon cotton, similar to those produced by gall-nuts. With other mordants, 
 salts, and acids, a variety of shades are obtained. The astringent principle is 
 found also in the twigs and wood, though less abundantly than in the leaves 
 and fruit. As to the economy of the lentiscus extract, as compared with other 
 astringents, details are still wanting. 
 
 Sumac, known also as sumach and shumach, consists of the ground leaves, 
 foot-stalks, and young twigs of several varieties of plants, technically known 
 as sumacs, but botanically belonging to the genus Rhus, of the family of the 
 Terebinthacese. The sumac of commerce is chiefly obtained from the Rhus 
 coriaria in the following manner : — A short time before the blooming of the 
 plant, in June or July, the younger twigs are cut off, dried in the sun, next 
 beaten, so as to detach the leaves and flower panicles, which are next coarsely 
 ground up by means of mill-stones. The shrub just named is a native of 
 Asia, but is cultivated in many parts of Europe, more especially in Sicily, 
 Spain, Southern France, and Hungary. 
 
 In the South of France a peculiar kind of sumac is prepared, and known 
 locally as rcdoul or redou. It is derived from the Coriaria myrtifolia, or 
 tanner's herb, which, according to the researches of M. Kibau, contains a 
 violently poisonous substance known as coriamyrtin. 
 
 The leaves of the Arbutus Uva-Ursi, better known in pharmacy than in 
 technology, are used as sumac in Dalecarlia (Sweden). 
 
 The following are the chief varieties of sumac known in the trade : — 
 Sicilian Sumac. — The most esteemed article, fetching always a high price 
 Spanish Sumacs. — Exported from Malaga, Priego, or Molina-Valladolid. 
 Portuguese Sumacs. — From Oporto. 
 Italian Sumacs. 
 French Sumacs. 
 
 The articles are classified here according to their amount of tannin, 
 

 BB 
 
 ■**£>& >*** 
 
 RBBB1B 
 
 502 
 
 DYEING AND CALICO PRINTING. 
 
 We have now to turn our attention to the chemical composition and other 
 properties of the substances enumerated. Tannin, or tannic acid, is the only 
 active principle of nut-galls, and, according to M. Guibourt's analysis, Aleppo 
 galls contain in 100 parts — Tannin, 65-0; water, 11*5 ; woody fibre, 10-5; 
 starch, 2 - o ; gum, 2'5 ; gallic acid, 2 - o ; ellagic acid, 2 - o ; brown extractive 
 matter, 2*5 ; chlorophyll, sugar, albumen, and inorganic matter, 2*0. 
 
 As shown by the following figures, galls differ largely in their richness of 
 tannin : — Aleppo galls contain, on an average, from 60 to 77*03 per cent ; 
 China galls, 58 to 77 per cent ; Smyrna galls, 33 to 60 per cent. 
 
 Tannin or tannic acid is readily prepared, in an almost pure state, from 
 galls previously coarsely powdered, by exhausting them either with aqueous 
 ether (9 parts of ether and 1 part of water), or with a mixture of equal parts 
 of alcohol and ether in the first instance, in a displacement apparatus. In the 
 lower vessel will collect two layers, the upper being ether, and the lower a 
 syrupy solution of tannin ; but if the mixture of alcohol and ether is employed 
 as directed by M. Mohr, the fluid, after having served to macerate the galls, 
 is evaporated to dryness. 
 
 Tannin is a whitish-yellow, amorphous, inodorous powder, possessed of an 
 astringent taste ; it is very soluble in water, less so in alcohol, and almost in- 
 soluble in ether, especially if the latter is anhydrous. When submitted to 
 heat, tannin fuses, and begins to decompose at about 210 , giving rise to the for- 
 mation of carbonic acid and pyrogallic acid, which sublimes, while a brownish 
 residue of gallohumic acid is left. The aqueous solutions of this substance 
 are precipitated by a great many salts, as well as acids, in consequence of the 
 smaller solubility of tannin in such liquids. 
 
 Solution of gelatin is precipitated by tannin solution, and from the latter, if 
 a piece of fresh skin be therein immersed, the tannin is gradually withdrawn, 
 because the skin (the derma proper) combines with the tannin, forming what 
 we term leather. 
 
 Solution of tartar emetic yields with tannin a white, and per-salts of iron a 
 deep blue, precipitate ; ferrous salts do not yield a precipitate with tannin unless 
 after lengthy exposure to air as a consequence of oxidation which has set in. 
 With acetate of lead tannin yields a white, and with silver salts a brown, pre- 
 cipitate. The solutions of the salts of the alkaloids are also precipitated by 
 tannin. Alkaline solutions of tannin become rapidly brown when exposed to air. 
 According to Dr. Strecker tannin is a glucoside, which under various influ- 
 ences is split up into gallic acid and glucose, the formula of tannin being 
 C27K2.CQ17 ' '- t£ splitting up into glucose is exhibited by — 
 
 C 27 H 22 I7 +4H 2 = 3(C 7 Hc0 5 ) + C6H I2 6 . 
 
 Gallic acid. Sugar. 
 
 This reaction takes place— (1) under the influence of a ferment, when coarsely 
 pulverised and moistened nut-galls are left to become mouldy, or also when 
 the decoctions are kept for a length of time ; (2) by boiling tannin with very 
 dilute sulphuric acid, or with a dilute caustic alkaline solution. 
 
 Gallic acid is always present to some extent in galls, and in the other 
 astringent substances above enumerated. It can be artificially obtained by 
 decomposing di-iodosalycilic acid by means of caustic potassa. Gallic acid 
 forms silky acicular crystals, soluble in 100 parts of cold and in 3 of warm 
 water, and also in alcohol and ether : its formula is C-H60 5 H 2 0. 
 
ASTRINGENTS. 
 
 503 
 
 When submitted to a temperature of about 210 it is decomposed, yielding 
 carbonic and pyrogallic acids ; at a higher temperature water, carbonic acid, 
 and gallohumic acid are formed. 
 
 Gallic acid is dissolved by concentrated sulphuric acid ; but since the gallic 
 acid is hereby deprived of its water of constitution, it is simultaneously con- 
 verted into rufigallic acid, C 7 H 4 4 . 
 
 Pyrogallic acid sublimes in white scaly crystals, and is chiefly remarkable 
 for its rapid absorption of oxygen when in alkaline solution, being thereby 
 converted into substances belonging to the ulmic series. 
 
 Since the goodness of galls and other astringent materials depends on the 
 quantity of tannin they contain, it is of importance to have a method of 
 rapidly estimating that quantity. M. Fehling has proposed, for this purpose, 
 the application of a standard solution of gelatin containing 10 grms. to the 
 litre : a proof test is made, in order thereby to estimate with precision the 
 weight of the tannin which is precipitated by 1 c.c. of this liquid. The wares 
 are tested by exhausting 1 grm. with pure distilled water, and from the bulk 
 of gelatin solution employed the quantity of tannin is calculated : the tannin 
 solution should be slightly acidulated or mixed with a little alum, since this 
 promotes the rapid precipitation of the tanno-gelatin compound ; instead of 
 gelatine solution, a solution of tartar emetic or of sulphate of cinchonin can 
 be employed. 
 
 Dr. GiAnther, of St. Petersburg, has recently investigated the different 
 analytical methods in use for the determination of the quantity of tannic acid 
 present in galls, catechu, ratanhia, kino, and other drugs. In an exhaustive 
 treatise* are described the various methods which have been practically tested 
 by the author with great care; as a general result arrived at by him, we may 
 state here that none of the different methods answer the purpose completely, 
 that is to say, that a method which yields excellent results with nutgalls is 
 not equally suitable for sumac, catechu, &c. ; for the good reason, that these 
 materials contain either other substances along with tannic acid or specific 
 modifications of the same. 
 
 M. Mittenzwei proposes to estimate the tannin in nut-galls by determining 
 the volume of oxygen absorbed in the presence of an alkali : — 1 grm. of tannin 
 absorbs 175 c.c. of oxygen ; gallic acid is thus formed, 07 grm. of which 
 absorbs also 175 c.c. of oxygen ; since galls contain, as above stated, both 
 gallic and tannic acids, the total absorption of oxygen by these together is first 
 determined, and that of the gallic acid present is next estimated in a fresh 
 portion of the galls after the tannic acid has been removed therefrom by a piece 
 of skin. For commercial purposes this method is utterly out of the question. 
 Lowenthal oxidises the tannin by means of permanganate of potash or 
 bleaching lime in standard solution, an excess of sulphate of indigo being 
 added. The tannin and indigo are oxidised simultaneously, and with the 
 disappearance of the colour the operation is completed. The articles required 
 for the process are a standard solution of pure tannin, containing in 1 c.c. 
 o - oor grm. of tannin dried at 212° F. ; a dilute solution of the best extract 
 of indigo, containing about 30 grms. of the paste per litre ; and a clear 
 solution of chloride of lime, which must be preserved in a dark place. The 
 first step is to standardise the solutions. To this end 20 c.c. of the indigo- 
 
 * " Pharmaceiitischc Zcitsdirift fur Rusaland," No. 6 and loHovving, 1870. 
 
^^^^^^^■1 
 
 S B 
 
 9EER5HSB 
 
 504 
 
 DYEING AND CALICO PRINTING. 
 
 liquid are put in a beaker with 1000 c.c.of water and 10 of hydrochloric (muriatic) 
 acid. The beaker is then set in a white porcelain basin, or a soup-plate, and 
 the chloride of lime liquor is carefully added, with constant stirring, till the 
 green colour disappears, and is replaced by a faint yellow. The quantity of 
 chloride of lime solution required to produce this result is then read off and 
 noted. A fresh quantity of the indigo solution is then mixed with hydrochloric 
 acid water exactly as above; 20 c.c. of the solution of tannin are then added, 
 and the chloride of lime liquor is dropped in as before till the green tint finally 
 disappears. From the number of degrees of the chloride of lime solution 
 required to produce this effect we subtract the number found as above for 
 the indigo solution alone. The remainder is the amount of the chloride of 
 lime solution, representing 0*020 grm. of tannin. It is advisable that about 
 ico c.c. of the chloride of lime liquor may correspond to c - 2 grm. of tannin. 
 In determining the value of a sample of sumac, myrobalans, &c, we take 
 5 grms., suitably ground up ; boil it for thirty to forty-five minutes with f litre 
 of pure water, let it cool, transfer the whole to a litre flask, make up with 
 water to the exact bulk of 1 litre, and shake up. When it has settled, 30 c.c. 
 of the clear liquid are taken out with a pipette for the actual analysis. This 
 quantity is mixed with the indigo solution, water, and hydrochloric acid as 
 above, and the standard chloride of lime-liquor is then dropped in from the 
 burette till the green colour disappears. If this process is carefully performed 
 the results are slightly too high. 
 
 Hammer takes the specific gravity of a solution of tannin, removes the 
 tannin, and takes the specific gravity again. From the loss apparent on this 
 second determination the amount of tannin present is calculated by means of 
 the accompanying table. (See next page). 
 
 The specific gravity of the solution to be tested is taken either with an 
 ordinary specific gravity bottle or a very fine hydrometer. For withdrawing 
 the tannin from its solutions the material used is raw hide. A piece of this, 
 cleaned and prepared as if for tanning, is well washed, dried at a gentle 
 heat till its weight becomes constant, rasped to powder, and preserved in that 
 state in a well-stoppered bottle. When wanted for the performance of an 
 analysis an amount of this, not less than four times the supposed quantity of 
 tannin, is weighed out, softened by steeping in water, well squeezed in a fine 
 linen cloth, so as to remove any superfluous moisture which would otherwise 
 dilute the solution, and then digested for a short time in the liquid to be 
 tested, with frequent shaking. In this manner the whole of the tannin may 
 
 ithdrawn from a liquid. 
 
 this method the sumac, gal's, #c, 
 
 must first be powdered, rasped, or otherwise well divided, boiled with water, 
 and exhausted in a displacement-apparatus. 1 part of the substance should 
 be completely extracted with 10 to 12 parts of water. The extract is made 
 up with water to some known weight, well shaken up to secure homogeneous 
 mixture, and the specific gravity of the liquid ascertained. A portion of the 
 solution, rather more than sufficient for the determination of the specific 
 gravity, is weighed off, and digested with an excess of hide-raspings, with 
 frequent agitation, as explained above. The liquid is then filtered through 
 fine linen into a hydrometer-tube or specific-gravity bottle, and its specific 
 gravity determined once more. From the loss the amount of tannin may be 
 calculated. 
 
ASTRINGENTS. 
 
 505 
 
 Sp. gr. at 
 
 Tannin 
 
 Sp. gr. at 
 
 Tannin 
 per cent. 
 
 2-6 
 
 15 C.=59° F. per cent. 15 C. = 59° F. 
 
 I'oooo o - o 1-0104 
 
 1-0004 ci roioS 27 
 
 I'OOo8 0"2 I-OII2 2 - 8 
 
 i'ooi2 o - 3 i-oii6 2-9 
 
 1-0016 0*4 I-OI20 3 - o 
 
 1-0020 - 5 I-OI24 3"I 
 
 1-0024 06 1-0128 3-2 
 
 1-0028 07 1-0132 3-3 
 
 1-0032 08 1*0136 34 
 
 1-0036 o-g 1-0140 3-5 
 
 1-0040 i'o 1-0144 3-6 
 
 1-0044 I " 1 1-0148 3-7 
 
 1-0048 1-2 1-0152 3-8 
 
 1*0052 1-3 1-0156 3 - g 
 
 1-0056 1*4 1-0160 4-0 
 
 1-0060 r - 5 1-0164 4-1 
 
 1-0064 i"6 1-0168 4-2 
 
 roo68 17 1-0172 4-3 
 
 1-0072 i*8 1-0176 4-4 
 
 1-0076 i-g 1-0180 4-5 
 
 10080 20 1-0184 4-6 
 
 1-0084 2-1 1*0188 4-7 
 
 1-0088 2-2 i-oig2 4-8 
 
 i-oog2 2-3 roig6 4g 
 
 1-0096 2-4 i-o20i 5-0 
 
 i-oioo 2-5 
 
 Persoz prepares a standard solution of tannin, containing 10 grms. per 
 litre, and another solution of 8 grms. tin crystals and 2 grms. sal-ammoniac 
 in 1 litre of water. A number of glass cylinders are provided, graduated in 
 cubic centimetres, and holding each 200 c.c. To perform an analysis he puts 
 into two cylinders 100 c.c. of the tin liquid each. To the first he adds 
 then 100 c.c. of the standard tannin solution, and to the second 100 c.c. of 
 the extract of 1 grm. of the sample of astringent material under examination. 
 Both cylinders are then, after well stirring up, set aside for twelve hours, when 
 the volumes of the precipitates are read by the graduation on the glass, and 
 the amount of tannin per cent is thus calculated. 
 
 Risler-Beunat collects the precipitate formed on adding the tin solution to 
 the extract of an astringent, filters, washes, dries at 212 F., and weighs. The 
 residue is then ignited and peroxidised by aid of nitrate of ammonia. The 
 peroxide of tin thus obtained is weighed, the amount of protoxide which it 
 represents is found by calculation, and this being deducted from the first found 
 weight the remainder is tannin. 
 
 According to Dr. Stenhouse, the tannic acid present in valonia does not 
 yield, on being boiled with dilute sulphuric acid, gallic acid and sugar, but, 
 instead of the former, a reddish-brown substance, which is sparingly soluble 
 in alcohol. The tannin of divi-divi also differs from that of galls, as is also 
 the case with the astringent principle of myrobalans, while sumac contains 
 
^t':>?-S?<~-' '^*<^ :: '. ; 
 
 BHi 
 
 506 
 
 DYEING AND CALICO PRINTING. 
 
 chiefly gallo-tannic as well as gallic acids. There is a great field for research 
 open as regards the native tannic and gallic acid compounds and substances 
 allied thereto, which, in many respects, are only very imperfectly known. 
 
 We have now to explain the use of these substances in dyeing and printing. 
 Nutgalls are used for the preparation of tannin, for the manufacture of 
 Morocco leather, for the preparation of black writing ink of good quality, and 
 next in many dyeing operations. Tannin (tannic acid) prepared as above 
 described is applied in some instances for fixing certain colouring matters, 
 especially the aniline derivatives, acting as a mordant. The galls known as 
 Knoppern or Piedmont galls are little used in England, though abroad they 
 are employed for tanning skins for the purpose of Morocco leather, and also 
 in dyeing and printing, while an extract of these galls is made for the latter 
 purpose. Valonias are often employed on the Continent instead of nutgalls, 
 but in this country, except in some operations of silk dyeing, they are not exten- 
 sively used in dyeing and printing. The tanners, however, use them largely, and 
 with decided advantage. Sumac is also substituted for galls, and is, although less 
 rich in tannic acid, advantageous in some cases, on account of the pure colours 
 it yields. All the astringent matters above named, especially sumac, behave as if 
 they contained a yellow colouring matter, imparting a more or less yellowish-drab 
 shade to all fibres, cotton, wool, and silk, but less readily to flax and hemp if 
 mordanted with alumina. The colour imparted under that condition by sumac 
 is decidedly yellow, but that given by nutgalls is a greyish-drab: if the tem- 
 perature of the dye-bath be raised, or the tissue immediately after dyeing 
 exposed to air, the colour becomes dirty, like iron rust. 
 
 Cotton which has been impregnated with oil (see Turkey-red) becomes, 
 when placed in a sumac bath, pale yellow, and turns, on subsequent mor- 
 danting, to bright yellow ; with acetate of tin as a mordant sumac yields a 
 yellow, and with zinc salts a brown upon cotton. Analogous shades can be 
 prepared by first steeping the cotton in the sumac decoction, and aluming the 
 tissues afterwards, but the depth of shade is less. 
 
 With the per-salts of iron as a mordant, the astringent materials yield, 
 according to the strength of the mordant, grey, blackish grey, or bluish grey 
 tints. The chief use made of sumac consists, as far as its application in 
 dyeing and printing is concerned, in being employed, with salts of iron and 
 copper, as mordants and oxidising agents, sometimes along with logwood, for 
 the production of greys and blacks. Nutgalls and sumac are used in Turkey- 
 red dyeing, as we have explained while treating of that process. When 
 it is dcsiicd to convert the greys and olives produced by quercitron into 
 chocolate or cinnamon-brown by means of the subsequent application of 
 madder, it is necessary to add to the madder bath an astringent decoction in 
 order to prevent the decomposition of the quercitron colour by the madder 
 bath ; sumac is also applied sometimes to the dunging mixture. (See 
 Madder, &c.) Stannated tissues (mordanted with tin compounds) destined to 
 be dyed with corallin and other coal-tar colours, are frequently passed 
 through decoctions of galls or myrobalans, in order to obtain the proper 
 precipitation and fixing of these colours upon the tissues, chiefly cotton. 
 Calico mordanted with pyrolignite of iron, fixed by ageing and passing through 
 a solution of an alkaline silicate, is dyed grey by means of sumac, galls, 
 myrobalans, bablah, &c, each of which substances taken separately only 
 
ASTRINGENTS. 
 
 507 
 
 serves for the production of that shade of colour. The grey obtained by the 
 use of Sicilian sumac is somewhat reddish, and this the more so the higher 
 the temperature of the decoction while applied ; it is therefore necessary not 
 to increase the heat above 50 , and to steep the goods only for about half- 
 an-hour. The shade of grey produced by galls is more ashy, while that 
 produced by bablah holds an intermediate position between the two. 
 
 The French sumac is less liable to yield foxy greys and blacks by being 
 exposed to a too high temperature. Nutgalls are rarely employed for dyeing 
 printed goods, on account of the property of galls of injuring the iron 
 mordants, that is to say, dissolving them, and spoiling the pattern by making 
 it spotted; a small quantity of galls added to logwood for black dyeing turns 
 the shade bluish-black. Bablah yields greys as pure as galls, while the colour 
 is brighter than that yielded by sumac, and it moreover soils the white 
 portions of the patterns less. Valonia holds the middle place between galls 
 and bablah as regards the colours it produces, but it is most advantageously 
 employed along with logwood ; when it is desired to dye calico, silk, or wool 
 uniformly black, astringent matters are very generally mixed with logwood. 
 For cotton, for instance, the operation is begun with a steeping of the tissue 
 for 12 hours in a bath of myrobalans, sumac, or galls, the goods being placed 
 therein while hot, and left until the liquid is quite cold ; the pieces are next 
 passed through lime-water (weak milk of lime), then put in a bath of sulphate 
 of copper, after that in a boiling logwood decoction, and next again in 
 a solution containing sulphates of iron and copper mixed. Sometimes the 
 operation is performed by first mordanting the goods with a salt of iron, and 
 dyeing in a bath made up of decoctions of galls, logwood, and sumac mixed. 
 Woollen goods, broadcloth chiefly, are dyed black by first dyeing them indigo- 
 blue (vat blue), and after that the tissue is placed in a boiling bath made up 
 of myrobalans and logwood (so called Sedan black), or in a boiling bath 
 of sumac, logwood, and fustic (so called Elbeuf black) ; afterwards, there is 
 added to these baths, while the goods are yet steeped therein, either sulphate 
 of iron alone, or a mixture of sulphate of iron and sulphate of copper, or, in 
 place of these, bichromate of potash. Silk is dyed black by being alternately 
 steeped in astringent baths and a solution of pyrolignite of iron. 
 
 Decoctions of galls, sumac, and valonia are ingredients in some kinds of 
 steam-grey and application-grey for cotton, along with acetate or pyrolignite 
 of iron ; the same astringent decoctions, mixed with logwood extract and red 
 liquor, or an iron mordant accompanied by an oxidising material, i.e., a copper- 
 salt and sal-ammoniac, are applied for the production upon cotton and wool of 
 so-called wood, wainscot, and other complex colours. The astringent decoc- 
 tions are also used, along with logwood extract, for the production upon silk of 
 some steam-blacks, nitro-sulphate of iron being used as a mordant. 
 
 Our ordinary black writing-ink is a ready-made colour which, by its mode of 
 preparation, is capable of fixing itself on paper. The best ink is made by adding 
 to a decoction of Aleppo, or Chinese galls, a solution of proto-sulphate of iron, in 
 which case the precipitation of the tanno-gallate of iron is rendered so slow 
 as to make it appear as if the ink were a solution, which, however, it is not ; 
 and the addition of some gum and sugar is required to keep the precipitate 
 suspended. One of the great drawbacks of ink thus prepared is its becoming 
 readily mouldy and viscous. The former defect is best remedied by the 
 

 5 o8 
 
 DYEING AND CALICO PRINTING. 
 
 addition to the ink of some corrosive sublimate, or, if this poison is dreaded, 
 there may be added a few drops of essential oil of cloves or a trace of carbolic 
 acid. The viscosity of ink is frequently due to the use of inferior materials in 
 its preparation, and to the neglect of filtering it through good filtering-paper, 
 an operation which is always very tedious. 
 
 Gallein. 
 
 A dye, or rather class of dyes, may here be noticed which stand in a close 
 relation to the astringents, and are prepared from pyrogallic acid. The first 
 step is the preparation of gallein. For this end, the inventor, Baeyer, heats a 
 mixture of 1 part of anhydrous phthalic acid and 2 parts of pyrogallic acid to 
 200 C, and keeps the mass at that temperature for some hours. When cold, 
 the residue is treated with hot alcohol, the solution is filtered and dilated with 
 water, which throws down a precipitate of the new body, gallein. It is of a 
 reddish-brown colour, but when in large lumps it exhibits a greenish-yellow 
 metallic reflection. It is insoluble in cold, and sparingly soluble in boiling, 
 water, forming a red solution. In alcohol, it dissolves readily with a deep red 
 colour. It is also soluble in caustic potash lye with a blue, and in ammonia 
 with a violet, colour. 
 
 Gallein is in many respects analogous to haematin. Trimesic, pyromellitic 
 and prehnitic acids, and the oil of bitter almonds also yield gallein on fusion 
 with pyrogallic acid. 
 
 The composition of gallein is found to be C 1 sHi 4 7 . If treated with zinc 
 and dilute sulphuric acid, it is converted into gallin, — a solid, colourless, 
 crystalline body, soluble in ether, and still more readily in an aqueous solution 
 of pyrogallic acid. When dried in a vacuum, its composition was found to 
 correspond with the formula CisHjeOg. It is sparingly soluble in cold, but 
 readily in boiling water, and still more readily in alcohol. Both in the solid 
 state and in solution it becomes very readily pink-coloured. It dyes tissues 
 in the same manner as gallein. 
 
 Gallein, if treated with concentrated sulphuric acid at 200° C, yields 
 ccerulein, dsH^C^. This body is almost insoluble in water, alcohol, and 
 ether. In acetic acid it dissolves more readily, forming a dirty green 
 solution. It is easily soluble in hot aniline, yielding a solution of a splendid 
 deep blue colour, which, if acidified with acetic acid, dyes wool indigo-blue. 
 Ccerulein dissolves in alkaline liquids with a beautiful green colour. The 
 solution dyes tissues previously mordanted with alumina a fine green. If an 
 iron mordant be used, the resulting shades are brown. Beth these dyes are 
 fast, and resist soaping. There appears to be a resemblance between ccerulein 
 and Lo-kao (Chinese green). 
 
 Reducing agents convert ccerulein into ccerulin, which dissolves in ether 
 with a yellow colour. If anhydrous phthalic acid is allowed to act upon 
 resorcin, fluorescein is formed, — a yellowish-red body soluble in alcohol. It 
 is a substantive colour, and dyes silk and wool yellow without the aid of any 
 mordant. 
 
 The following substances, though possessing tinctorial powers, and capable 
 of being applied in dyeing and printing, are, from a variety of reasons, not in 
 actual use : — 
 
 Alder Bark contains a colouring principle, along with tannin. With 
 
GALLEIN. 
 
 509 
 
 preparations of tin and alumina, it yields a variety of buffs, yellowish-brown 
 and orange shades, which have no distinctive recommendation. In some 
 parts of England, it was formerly used for dyeing blacks on silks. The bark 
 was well boiled up in soft water, and the mixture was allowed to act upon 
 scrap iron for a considerable time. The blacks dyed with this liquid are said 
 to have been remarkably rich, soft, and permanent. It was also employed, 
 like logwood and galls, with copperas and iron-liquor, and was used alone 
 with fustic for browns. It is still, we believe, used by jobbing dyers in rural 
 districts. 
 
 Algaroba, a substance not unlike catechu in appearance and properties. 
 It is obtained from the La Plata, and contains tannin, mixed with a deep brown 
 colouring matter. 
 
 Amalic Acid. — This substance is obtained by decomposing caffein by 
 means of chlorine gas. Its composition is C 4 (CH 3 ) 4 N 4 7 -|-H20. It forms 
 transparent colourless crystals which do not lose their water at ioo° C. With 
 ammonia, potash, soda, and baryta, it forms a series of compounds of a fine 
 violet. The scarcity of the material prevents these from being of any prac- 
 tical importance. 
 
 Anthokirrin. — A yellow colouring matter obtained from the flowers of the 
 toad-flax {Antirrhinum linaria). The flowers are extracted with hot alcohol, 
 the liquid evaporated to dryness, and the dry residue exhausted with water to 
 remove sugar and gum. The insoluble part is then treated with alcohol, the 
 solution is filtered and evaporated to dryness, and the residue taken up with 
 ether. On evaporating the ethereal solution, the colouring matter is deposited 
 in yellow needles, which, if dried and exposed to heat, sublime undecomposed. 
 Alkaline liquids dissolve anthokirrin with a red colour. In ammonia and alka- 
 line carbonates it dissolves with a yellow colour, and is re-precipitated by acids. 
 Concentrated mineral acids dissolve it with a red colour, which turns to 
 a yellow on standing. Strong aqueous solutions give an orange precipitate 
 with the acetate of lead, a yellowish-green with salts of copper, and an orange 
 with solutions of tin. With alum it gives a yellow lake. It dyes yellow 
 shades of little value. 
 
 Areca Nuts have been employed, or at least recommended as an astringent. 
 They contain also areca-red, a brownish-red dye, insoluble in cold but soluble 
 in boiling water. (" Morin. Journ. Pharm.," viii., 449). 
 
 Bablah, Neb-Neb, Neb-Nab, or Babulah is the fruit of Mimosa cineraria, 
 a tree growing in India and along the Senegal. It contains gallic and tannic 
 acids — the former in considerable amount — and a red colouring matter. The 
 total amount of tannin and gallic acid in African samples is, according to 
 Chevreul, 57 per cent, and in those from India 49 per cent. It cannot be used 
 as a substitute for sumac, galls, or myrobalans on account of the accom- 
 panying red matter, except in some particular cases. With mordants of iron 
 and alumina it yields fawn and drab shades. Its reputed power of rendering 
 all colours fast is imaginary, and it is now very rarely used. 
 
 Barbatimas. — An astringent, from Brazil. 
 
 Bearberry, the fruit of Arbutus Uva-Ursi, contains astringent matter, and 
 is sometimes used in dyeing black. 
 
 Bilberries (Whinberries or Whortleberries), the fruit of Vaccinium myrtiUus, 
 were formerly employed for producing certain blue and purple shades on silk. 
 The colours thus obtained are very fugitive. 
 
hmbbm nasBBH 
 
 P 
 
 ■ 
 
 ■^HH 
 
 WiBUiBiB— B^^^OiBW 
 
 5 io DYEING AND CALICO PRINTING. 
 
 Brauna-wood (Mclanoxylon brauna) is furnished by a tree growing in the 
 province of Minas Geraes, in Brazil. Its use was patented in 1857, anc * it was 
 said to have a strong affinity for cotton "with or without mordants," and to 
 produce browns, drabs, slates, salmons, buffs, fawns, and blacks more 
 permanent than those obtained by other means. 
 
 Butter-nut Bark, the bark of Juglans alba, a kind of walnut, growing in 
 the north-eastern states of the American Union. It is said to yield fast blacks 
 with iron mordants, and deep browns with preparations of alumina. 
 
 Cactin, a red colouring matter obtained from the flowers of many species 
 of cactus, especially C. speciosus. It has been examined by Vogel and 
 Wittstein, and is theoretically interesting on account of its relations to 
 cochineal. It has been suggested that the cochineal insect does not actually 
 generate the colouring matter which it contains, but merely extracts and con- 
 centrates principles pre-existent in the juices of the plant upon which it feeds, 
 and which is also developed, without its aid, in the flowers. So far, this view 
 does not seem borne out by experiment. A considerable quantity of a 
 carmine-red colouring matter can be extracted from the cactus flowers by 
 treatment with weak alcohol. It is soluble in water. From the portion left 
 undissolved by the dilute alcohol, a further amount of a scarlet colour is 
 obtained by treatment with a mixture of alcohol and ether. Neither of these 
 colours is in use, and a further examination of their properties is needed. 
 The fruit of the C. cochcnilifer contains also a coloured juice, which imparts a 
 deep red tinge to the urine of animals fed upon it. 
 
 Canadian Yellow-root. — The root of Hydrastis Canadensis affords a yellow 
 dye — hydrastin, which is turned red by sulphuric acid and chromate of potash. 
 
 Carapa-root. — The root of a plant found in Guayana. Its bark contains 
 one yellow and two red colouring principles. (See "Journal de Pharmacie," 
 xxxv., p. 189. 
 
 Chestnut. — The whole tree, especially the nuts and the sap, contains 
 astringent matter, which was patented by C. L. Girourd as a substitute for 
 gall-nuts, under the horrible name of " damajavag." The extract of chestnut 
 is still occasionally used on the Continent for adulterating the extracts of 
 logwood and other dye-woods. 
 
 Chicory. — The leaves of this plant are used, according to D. Metcalf s 
 patent, as a substitute for woad in the indigo-vat. Like the leaves of 
 rhubarb when applied to the same purpose, they probably serve merely to 
 promote fermentation. 
 
 Chrysoretin. — A yellow, resinous matter, obtained from senna leaves. 
 
 Coccedia viridis. — This plant yields, according to Salm Horstmar, a green 
 dye, distinct from chlorophyll. (" Pogg. Ann.," xciv., p. 466, and cxv., p. 176). 
 
 Cocoa-nut Tree. — In a patent, obtained by Mr. J. H. Baker (No. 5139, 
 March 29, 1825), the whole or every part of this tree is claimed as a dye- 
 ware, especially the husk enclosing the fruit, and the foot-stalks of the leaves. 
 The dye was to be extracted by water, cold or boiling, or by solutions of lime, 
 potash, ammonia, &c, and was to serve for dyeing nankeens, blue-blacks, &c. 
 The infusion was likewise to serve as a substitute for nut-galls in Turkey-red 
 dyeing. The material does not appear ever to have come into practical use. 
 
 Cork. — According to T. Bury's patent (Feb. 18, 1823), the bark of the 
 cork-tree may be used in dyeing nankeens upon cotton, along with the 
 
ASTRINGENT DYES. 
 
 5" 
 
 " usual mordant." Cork-cutters' waste, digested with nitric acid, yields a 
 primrose-yellow colouring matter, — probably an impure or modified picric 
 acid, — which was at one time used for dyeing yellow waistcoatings. 
 
 Dyer's Woodruf (Aspcrula tinctoria) is cultivated and used to a small 
 extent in Dalmatia as a substitute for madder. 
 
 Gammam. — A dye-ware from Tunis. Samples were sent to the Exhibition 
 of 185 1, but it has not been introduced into the market. 
 
 Golden Rod (Sulidago Canadensis) is stated to produce good yellow 
 shades, — similar to those yielded by weld,— both upon animal and vegetable 
 tissues. It is not met with in the English market. Its mordant is alum. 
 
 Green Ebony. — A wood sold under this name has sometimes been used as 
 a yellow dye, especially in compound colours, such as greens. 
 
 Heath. — In former times common heath was used as a dye-ware, and gave 
 a yellow colour upon woollen goods. It is now quite superseded by richer 
 woods and barks. 
 
 Hellebore (Hellcborus trifolius). — The Canadian three-leaved hellebore is 
 used by the native Indians for dyeing skins and wool a yellow. 
 
 Hemlock. — The bark of the "hemlock spruce" (Abies Americana) contains 
 tannin, and has been experimentally used for dyeing. The results were not 
 encouraging, as the blacks and other sad colours produced have an unpleasant 
 rusty-red, or, as it is technically called, " foxy " reflection. 
 
 Hiccory. — The bark and nuts of the "American hiccory, or walnut tree " 
 were claimed by Dr. Bancroft, in his patent of October 23, 1775, as capable 
 of producing yellow and green colours with a mordant of alum and verdigris. 
 The material never came into extended use. 
 
 Holly. — Ilixanthine, a principle obtained from the common holly, is insoluble 
 in cold water, soluble in hot water and alcohol, with a yellow colour ; insoluble 
 in ether, but soluble in hot concentrated hydrochloric acid. With alum it 
 dyes a yellow, and with ferric chlorides a green. 
 
 Hollyhock. — The common garden hollyhock is said to contain, in its stem, 
 a blue colouring matter not unlike indigo. This colour has never been 
 obtained upon a manufacturing scale, and its properties are still a matter of 
 dispute. 
 
 Horse-chestnut. — The cotyledons of the horse-chestnut fruits contain, 
 according to Rochleder, argyrescin, a yellow colouring matter. 
 
 Horse-radish. — This plant contains a yellow colouring principle, not 
 in use. 
 
 Khail-cedra, obtained from Khaya Senegalcnsis, yields red or yellow 
 colours. (Caventon, "Journ. Pharm.," xvi., 355, and xxxiii., 123). 
 
 Lamium album {The Dead Nettle). — This plant yields yellow and green 
 colours of no value. 
 
 Lamium purpureum produces, with preparations of tin, a reddish-grey, 
 and with iron liquor a greenish colour. 
 
 Lawsonia inermis, the henna of the Arabs, is used in the East for staining 
 horse-hair, leather, and human finger-nails a reddish-purple. Its use has been 
 patented in France for dyeing blacks. 
 
 Lithospermum arvense. — The root-bark yields a red colour resembling 
 that obtained from alkanet root. It forms, however, a blue solution in ether, 
 whilst alkanet gives with the same solvent a red. 
 

 pm 
 
 ____l ■■ 
 
 mumffffffnfi 
 
 512 
 
 DYEING AND CALICO PRINTING. 
 
 Mahaleb. — A shrub whose fruit yields a violet dye. 
 
 Mahogany-tree Bark. — This bark contains a small amount of colouring 
 matter, and has been used for producing a variety of sad shades. The result 
 was unsatisfactory, and the ware is not in use in England. 
 
 Mangrove. — The bark of the red mangrove was patented by Dr. Bancroft 
 as yielding a variety of red, brown, and nankeen shades, with alum, copper, 
 lead, &c. It was at one time in common use, but has been altogether 
 abandoned. 
 
 Nitrocuminic Acid. — Jules Persoz states that this acid, when hot, com- 
 municates to calico a variety of shades from scarlet to pink. 
 
 Nucin. — Green walnut-shells are extracted with ether. The extract is 
 treated with neutral sulphate of copper till it assumes a blood-red colour. 
 It is now filtered, and mixed with nitric acid till it turns to a greenish-blue. 
 The nucin thus set free is dissolved in ether, and evaporated over sulphuric 
 acid. It is a yellow powder, which dissolves in ammonia with a red colour. 
 
 Nymphsea alba [The White Water-Lily), described in some works under 
 the name nenuphar, contains astringent matter, and is sometimes used in 
 Eastern Europe as a substitute for galls or sumac. 
 
 Palisander Wood is a red dye-wood obtained from Madagascar. It 
 resembles santal-wood in many of its properties, but it produces shades less 
 orange in their tone. It must be observed that the names Palisander and 
 Palixandre are, on the Continent, often applied to the common rosewood of 
 cabinet-makers. (See Arnaudon, "Ciment.," viii., p. 278). 
 
 Paracarthamin is obtained by the action of sodium amalgam upon rutin. 
 It is turned green by alkalies, and red by acids. It is found in dogwood, the 
 blackberry, the willow-stem, and in the bark of certain acacias. 
 
 Phycocyan, Phycoerythrin, Phycohaematin, are blue and red colours 
 obtained by Kiitzing from sea-weed (Bytiplca tinctoria). The colours are 
 quickly destroyed by sunlight. 
 
 Pittacal. — On adding baryta-water to solution of picamar (tar-oil deprived 
 of its acid), pittacal falls down as a dark-blue powder, inodorous, non-volatile, 
 very sparingly soluble in water. It dissolves in sulphuric acid with a green 
 colour, having a crimson cast. With tin and alum mordants, it dyes fast 
 blues on cotton. 
 
 Polygonum tinctorium. — The fresh leaves are exhausted with ether, and 
 a portion of the liquid is distilled off, when some indigo-blue is separated. 
 The remainder is evaporated to dryness, and exhausted with alcohol. The 
 extract is filtered, evaporated again to dryness, and the residue exhausted with 
 hot water. A hard reddish mass remains, insoluble in water, slightly soluble 
 in alkaline liquids and in acetic acid, and readily soluble in ether. The 
 alcoholic solution forms a fine red lake with alum. 
 
 Pomegranate Root Bark. — This bark yields shades similar to those 
 obtained from quercitron bark. 
 
 Purple Heart. — The wood of Copiaba pubifolia, a tree of Guayana. It 
 produces purple shades with tin and alum mordants. 
 
 Privet Berries contain ligulin, a crimson dye, soluble in water and alcohol, 
 but insoluble in ether. Privet leaves contain ligustrin, insoluble in ether and 
 alcohol, but soluble in water and dilute alcohol. Sulphuric acid turns the 
 solution a deep indigo-blue, which, when diluted with water, becomes violet. 
 These solutions are not precipitated by metallic salts. 
 
EXTRACTS OF DYE-WOODS. 
 
 513 
 
 Saw-wort (Serratula tinctoria). — This plant is stated by Bancroft to yield 
 yellow shades resembling those produced by weld. 
 
 Sunflower Seeds contain helianthic acid, which, when treated with dilute 
 hydrochloric acid in a current of hydrogen, is resolved into glucose and a 
 violet dye. 
 
 " Syria." — Under this curious name is sold the imperfectly-exhausted 
 residue of Coccus ilicis. 
 
 Viridic Acid, a colouring matter contained in unroasted coffee. It is 
 turned a fine deep green by alkalies, and dissolves in sulphuric acid with a 
 crimson colour, but on the addition of water is deposited in blue flakes. 
 White of egg placed in contact with raw coffee-beans takes a fine green colour 
 which might be advantageously used by confectioners, instead of the unwhole- 
 some pigments sometimes employed. 
 
 Virginia Creeper (Ampclopsis hcdcracca). — The red leaves of this well- 
 known climber contain a red colouring matter, cissotannic acid. 
 
 Preparation of Extracts of Dye- Woods. 
 
 We have now to turn our attention to a collateral branch of the dyeing 
 operations, viz., the mode of preparation of extracts of the dye-woods employed 
 by the dyers and calico-printers. This manufacture has sprung up with the 
 more extensive use of the wares in question, and is of comparatively recent 
 date, owing in part also its origin to the fact that the dye-woods are not 
 directly fit for use in the calico-printing business. The manufacture of these 
 extracts is carried to a high degree of perfection, and is performed in the 
 following manner: — By means of suitable machinery, the woods are reduced 
 to a coarse powder, or to small chips cut generally in a direction perpen- 
 dicular to their fibres. This operation requires also a large amount of moving 
 power. The coarse powder or chips thus obtained are directly exhausted by 
 means of water, or are left exposed in heaps, in a moist state, to a kind of 
 oxidising fermentation, whereby the solubility of the colouring matter is 
 increased and the exhaustion thereof by water facilitated. This is especially 
 done for logwood. 
 
 It is clear that in order to carry on the exhaustion of the woods with the 
 least possible expenditure the quantity of water to be used should be as small 
 as possible, because the greater part of that vehicle has to be got rid of by 
 evaporation. Some manufacturers carry on their operations in open tanks, 
 applying water at 6o°or ioo°, but others prefer to work at a temperature above 
 ioo°, and then of course in closed vessels. The annexed figure (Fig. 23) gives 
 a view of the construction of these vessels: c represents a copper boiler fixed 
 between two cast-iron columns, D, so as to be movable on the imaginary axis, 
 a a, that is to say that c at the top of the figure can, by turning the boiler 
 round that axis, be brought to where q stands in the figure, and be reversed 
 again if required ; b, manhole, hermetically closed by means of the screw, c ; 
 c e, two handles or rings, fit for lifting off the piece b, manhole cover;/, copper- 
 made false bottom, perforated with holes ; to this piece of copper is fastened 
 a piece of brass wire gauze of narrow gauge ; K, perforated worm tube, which 
 by means of the pipe, /, communicates with a steam-boiler. The pipe g, 
 which communicates with the cavity below the false bottom, is in con- 
 nection with three tubes, furnished with three taps. 111, n, and (the latter is not, 
 
 2 L 
 

 ■D 
 
 liflfff! 
 
 514 
 
 DYEING AND CALICO PRINTING. 
 
 however, visible in the cut, being placed in front of and before »); m serves 
 for the introduction of pure water, n and for running off the decoction made 
 of the dye-wood under pressure of the steam, but if the steam is turned off 
 the liquor is run off by q, a small air admission tap being provided at/>. 
 
 The evaporation of the liquors obtained from the exhaustion of the woods 
 with water is effected in various ways ; sometimes vacuum-pans are used, but 
 they do not answer the purpose very well for extracts which have to be con- 
 centrated above a specific gravity of 1*134, on account chiefly of the difficulty 
 experienced by the bubbles of aqueous vapour in escaping from a mass of 
 viscous liquid ; the evaporation is therefore most frequently carried on by 
 means of double bottomed shallow pans heated by steam. 
 
 In order to make extract of quercitron, this material, which is imported 
 ready pulverised, has to be boiled for a length of time with water, and the 
 
 Fig. 23. 
 
 liquid to be separated from the dregs by filtration, the residue being pressed, 
 and the clear liquid is then evaporated to dryness. 
 
 The extracts of dye-woods contain, in addition to the colouring matter, all 
 the soluble salts contained in the wood, also the nitrogenous matter, the 
 glucosides, and other vegetable matters soluble in water, which it would be 
 very useful to remove if it could be done efficiently and without too great 
 expense, since most of these substances impair the beauty and brightness of the 
 dyes made with these extracts, and, moreover, add to the cost of transport, 
 as well as render the extract liable to become mouldy. A great desideratum 
 also is the obtaining of inexpensive and suitable solvents for the removal of 
 the colouring matters from the woods in a purer state. It has been proposed 
 
EXTRACTS OF DYE-WOODS. 
 
 515 
 
 to extract the colouring matters of dye-woods by means of weak solutions 
 of soda, potash, or ammonia, caustic or carbonated, and to neutralise the 
 decodtion thus obtained by the cautious addition of an acid. Others have 
 reversed the method, treating the dye-ware first with an acid or an acid salt, 
 and then neutralising with an alkali. Processes of this nature have been 
 patented by Leeshing, No. 1160 (1855), and by Roberts and Dale, No. 1988 
 (1857). The objection to operations of this nature is, that even brief contact 
 with alkaline liquids, especially at an elevated temperature, impairs the beauty 
 of most of the colouring matters concerned. The utilisation of the exhausted 
 wood also is a matter of importance ; an attempt has been made to manu- 
 facture acetic acid from the residues, but this requires complicated 
 apparatus; perhaps the utilisation of this material along with other sub- 
 stances, as compressed artificial fuel, might be worth while trying. 
 
mamum/urn 
 
 n 
 
 ^^^HH^R^H ^B^HI 
 
 BOB 
 
 ■■■■ 
 
 (516) 
 
 CHAPTER VII. 
 
 MORDANTS. 
 
 'TP HOUGH much has been said, incidentally, in the preceding pages con- 
 _•*- cerning mordants, their systematic consideration remains to be un- 
 dertaken. The subject is remarkably complicated from two reasons : — 
 Different dyers and printers produce identical results by means so widely 
 varying, that what one finds in his peculiar mode of procedure to be useful 
 or even necessary, another would at once put aside as worthless. Again, the 
 nomenclature of all the articles used in tinctorial industry is in the highest 
 degree perplexing. One and the same substance is known under different 
 names, some of them originating in the workshop ; others being specimens of 
 almost every stage through which chemical theory has passed. As far as 
 possible we shall endeavour to point out which of these substances are 
 identical, and which really distinct. 
 
 A few general considerations will be necessary before entering upon the 
 practical part of the subject. That mordants are a class of bodies which 
 serve to fix colouring bodies upon textile fibres is well known. It will have been 
 perceived from the foregoing portion of this work that few colouring matters 
 are able to attach themselves to cellulose — whether in the form of cotton, 
 linen, or jute, &c. — without the interposition of some third body, which 
 having an affinity for both, brings them into a more or less permanent state 
 of combination. Animal tissues and fibres, wool, alpaca, hair, horn, leather, 
 and silk combine unaided with a much larger number of dyes. Yet even in 
 their case mordants are often employed to give additional brightness and per- 
 manence to the shades produced, or to modify the effect in some peculiar 
 manner. Hence most mordants are at the same time alterants, the shade 
 fixed upon the fibre being not that of the dye-ware in its free state, but that 
 of a combination formed between some one or more of its constituents and 
 the mordant. 
 
 A mordant to be useful must possess a peculiar combination of qualities. 
 It must have a strong affinity or attraction at once for the fibre and the colour. 
 But these attractions must not pass certain easily recognised limits. If too 
 powerful, the work done will be uneven and spotty ; certain parts of the goods 
 either from first entering the dye-pan, from presenting a slightly abraded 
 surface,* or from a variety of other causes, will take up an excess of the colour, 
 
 * The mechanical condition of the surface of a tissue has a powerfully modifying effect upon 
 its affinity for mordants and colours. Any portion which has been roughened by friction takes 
 a deeper, though often a duller, colour than parts of the same fabric which remain smooth and 
 
MORDANTS. 
 
 5i7 
 
 whilst the remaining parts receive less. If, on the other hand, the affinity of 
 the mordant for fibre and colour is too feeble in itself, or is over-balanced by 
 some other body present, the shades resulting will be impoverished, meagre, 
 and probably fugitive. 
 
 If a mordant, as is sometimes the case, has a much more decided affinity 
 for the colouring matter than for the cloth or yarn, the colour produced is 
 deposited not on or in the fibre, but at the bottom of the dye-beck, in the 
 shape of a lake or pigment, whilst the goods are merely stained or smeared 
 with colour. Hence, not every metallic base or salt which has a strong 
 affinity for colouring matters, and forms abundant and possibly beautiful pre- 
 cipitates in solutions of dye-wares, is fitted for use as a mordant. It is 
 necessary for the mordant to combine both with fibre and colour with 
 regularity, and not too rapidly, so that the compound formed may not be 
 loosely plastered over the surface of the fibre, but may inter-penetrate its 
 substance. The result will, otherwise, be uneven, fugitive, and dull. 
 
 Another essential condition is that the mordant must have no injurious 
 effect upon the fibre. If too strongly acid or alkaline it will have a corrosive 
 action, and the goods, as it is technically called, will be " tendered." The 
 colouring matter may also be "flattened " or deprived of its lustre by an ill- 
 compounded mordant. The great majority of mordants are acid, and the 
 practical difficulty is duly to proportion the acid to the base, so as to produce 
 a well-balanced whole. If there is too little acid the mordant becomes too 
 " dead," and the base is delivered to the fibre rapidly and irregularly. If the 
 acid is in excess the mordant parts with its base too sparingly and slowly, 
 and the tissue is weakened. 
 
 It is also important that mordants should not of themselves affect: the colour 
 of the fibre. When, like the salts of iron, manganese, or copper, they possess 
 an independent tinctorial power, their use is limited to some particular set of 
 shades. Thus, an iron mordant imparts of itself a buff colour to vegetable 
 fibre. It can, therefore, generally be used only where the shade intended is 
 a black, brown, olive, drab, or some other "sad" colour. Compounds of tin 
 and of alumina, which leave the fibre colourless, can be used for light and 
 bright shades. 
 
 Mordants, as a matter of course, are presented to the fibre and to the colour 
 in a liquid state, but they must be capable of becoming insoluble as the com- 
 bination is accomplished. This change of condition, from a soluble to an 
 insoluble state, is brought about in several ways. Frequently it is a case 
 
 glossy. This is a serious difficulty for the jobbing dyer, since garments which have been worn 
 always present inequalities of surface, and are, therefore, when re-dyed certain to appear 
 Bpotty. We may here briefly refer to the different " appetite " for mordants and colours pre- 
 sented by different growths of wool. Two different wools treated in exactly the same manner 
 with the same quantities of the same dye-wares do not necessarily take the same intensity, 
 sometimes not even the same tone, of colour. The climate where the wool is produced, the 
 breed of the sheep, the nature of their food, and possibly other causes have a modifying 
 influence. Hence woollen manufacturers who pride themselves on the uniformity of their 
 results are generally careful to use, year by year, the same growths of wool for the same class 
 of goods. 
 
 The varying affinities of different kinds of cotton for colour have been pointed out in an 
 earlier portion of the work: p. 28. 
 
- 
 
 BRBflSEBBE^E 
 
 518 
 
 DYEING AND CALICO PRINTING. 
 
 of ordinary precipitation, the mordant and the colour, each of them soluble, 
 forming an insoluble compound together within the pores of the fibre, much 
 as they would if mingled in a glass. Sometimes the mordant in a sufficiently 
 dilute state is decomposed on coming in contact with the fibre, within which 
 an insoluble oxide or sub-salt is deposited. In other cases insolubility is pro- 
 duced in consequence of the escape of some volatile acid ; thus, when cotton 
 is steeped in a solution of the acetate of alumina and dried, the acetic acid is 
 volatilised, whilst the alumina with which it was combined remains in an 
 insoluble state in or upon the fibre. 
 
 Hence we learn that such bodies only as are unstable in their constitution 
 — their components being held together by but feeble affinities — can play the 
 part of mordants. On the other hand, stable compounds do not readily yield 
 up to the fibre any part of their constituents. Thus common alum is a stable 
 salt, and, therefore, if used alone it is a feeble mordant. If it is converted 
 into basic alum, whose ingredients are held together more loosely, its power 
 is greatly increased. It must be remarked that the bases of mordants are not 
 of a very decided basic character, but hold an intermediate position, and are 
 capable of playing the part either of acids or bases, according to circumstances. 
 Thus alumina and the oxides of tin can combine either with acids or with 
 alkalies. 
 
 Many mordants if preserved for some time undergo spontaneous decom- 
 position, an insoluble sub-salt being deposited, whilst a small portion of the 
 base remains in solution in an excess of acid. This change is accelerated by 
 dilution, by the application of heat, by exposure to light, and in some cases 
 by the action of very low temperatures. " Nitrate of tin " is very unstable at 
 an ordinary summer heat, whilst the nitrates of iron are often converted into 
 a paste-like mass if exposed to intense frost. 
 
 There is a variety of opinion as to what is deposited upon the fibre by any 
 mordant. Some consider that it is a hydrated oxide of aluminium, tin, or 
 other metal. Others hold that the body thrown upon the fibre is a basic sub- 
 salt, retaining a certain quantity of the acid in which the tin, &c, may have 
 been originally dissolved. This latter view is strengthened by the fact that 
 the resultant shade is modified by the acid originally present. A sulphate of 
 tin, or a chloride of tin, containing an admixture of sulphuric acid, gives with 
 logwood a redder shade upon wool than is produced if a pure chloride of tin 
 be applied, and this difference no amount of washing will remove. 
 
 One and the same mordant, however fully it possesses the attributes we 
 have just described, does not suit equally weii for all cases. What is 
 efficacious upon an animal fibre may be useless or even hurtful if applied to 
 vegetable tissues. Certain dye-wares, moreover, are suited to some particular 
 mordants, and give unsatisfactory results with others. Thus with madder 
 alumina is pre-eminently the mordant to be used, whilst with cochineal and lac 
 dye tin has an indisputable superiority. Some acids deliver the metallic base 
 more readily to one class of fibres than to another. Thus if a piece of any 
 tissue, consisting of a mixture of cotton and woollen, be steeped in dilute 
 nitrate of iron, a buff colour will be produced upon the cotton, whilst the wool 
 remains practically untouched. If, on the other hand, a similar piece of cloth 
 is soaked in dilute chloride of iron, the result is reversed, the iron being mainly 
 deposited upon the wool. 
 
MORDANTS. 519 
 
 The mordants for wool and worsted dyeing and printing are generally the 
 most decidedly acid. Those for silk are more neutral, and in cotton dyein<* 
 and printing excess of free acid must be carefully avoided. On the other 
 hand, cotton can be successfully mordanted with preparations, in which the 
 solvent is an alkali, and the matter to be deposited on the fibre plays the part 
 of an acid, such as the stannate and the aluminate of soda, which are 
 advantageously used for cotton, whilst with animal fibres their applications 
 are very limited. 
 
 Mordants are either applied preparatory to the colouring matters (the 
 ordinary routine for cotton), along with the colours (the usual procedure for 
 wool), or, though less frequently, after the colour. 
 
 The metals which enter into the composition of mordants are aluminium, 
 tin, iron, chromium, lead, copper, zinc, arsenic, mercury, antimony, and man- 
 ganese. Bismuth, nickel, cobalt, tungsten, molybdenum," an'd magnesium 
 have also been applied. Even sodium performs functions which can only be 
 regarded as those of a mordant. 
 
 The acids employed are the nitric, hydrochloric, sulphuric, tartaric, oxalic, 
 hyposulphurous, boracic, silicic, and phosphoric. 
 
 A. Mordants of Tin, technically known as "Tin-Spirits." 
 Tin is employed as a mordant in three different states of chemical com- 
 position, the protoxide, the sesquioxide, and peroxide, or their corresponding 
 chlorides. The protoxide of tin, known also as stannous oxide, is a 
 compound of the metal with the smallest possible quantity of oxygen. 
 It forms with the acids colourless salts and solutions, which have a 
 strong affinity for a further quantity of oxygen, and are hence powerful re- 
 ducing agents. With alkalies, such as soda and potassa, it is also capable of 
 playing the part of a feeble acid, forming compounds known as stannites. 
 
 The sesquioxide of tin is a body concerning whose nature and properties 
 chemists are not agreed. Its compounds are of a reddish-amber colour, and 
 are not permanent, passing, if kept for any length of time, into variable 
 mixture of the other oxides, combined with whatever acids were present. 
 
 The peroxide of tin, known also as stannic oxide, stannic acid, binoxide of 
 tin, contains the highest proportion of oxygen. Its salts and solutions, if 
 the acids employed be perfectly pure, are colourless. Should, however, the 
 smallest trace of iron be present they have a very faint yellow colour. The 
 compounds of the peroxide of tin have an oxidising effect upon bodies with 
 which they are brought in contact. 
 
 Generally speaking the proto-salts of tin are applied to wool, and the per- 
 salts to cotton. The sesqui-salts, the consumption of which is more 
 limited, are used in certain cases to both. The compounds where tin plays 
 the part of an acid, such as the stannites and stannates, are almost exclusively 
 restricted to cotton dyeing and printing. 
 
 The successful preparation of tin-mordants is a matter of great nicety, 
 demanding close attention to certain minute particulars, which can scarcely 
 be explained in writing. Purity of the ingredients used is a matter of vital im- 
 portance. The tin should be the finest " grain-bar," the " lamb and flag " brand 
 being generally the most satisfactory. The economy effected by the substitution 
 of lower qualities, containing traces of iron, copper, arsenic, antimony, &c, 
 
HI 
 
 BBBBB 
 
 wwww 
 
 I 
 
 DYEING AND CALICO PRINTING. 
 
 is a poor compensation for occasional and costly failures. The like care must 
 be taken in the selection of the acids employed. Traces of iron and of 
 arsenic are very pernicious. The coarse hydrochloric (muriatic) acid obtained 
 as a secondary produd at the alkali-works, and known in commerce as " tower- 
 salts," is not trustworthy. It sometimes yields good results, but as frequently 
 occasions mischief, the more serious as the cause is not readily detected. 
 The hydrochloric acid employed should be " cylinder-salts," made from clean 
 salt, and from sulphuric acid free from arsenic. The presence of sulphurous 
 acid, of free chlorine, of arsenious acid, or arsenical chlorides, leads to 
 annoying complications. Both the hydrochloric and the nitric acid used 
 should be free from sulphuric acid, an agent which, indispensable as it is, 
 should never be introduced except where directed, and then in exactly known 
 quantities. The sulphuric acid employed should be prepared from Sicilian 
 sulphur, and not from iron- or copper-pyrites, which contain arsenic in greater 
 or smaller quantities. It should also be free from nitrogen compounds. 
 
 The following instructions will be of use in judging of the quality of the 
 materials used in the preparation of tin mordants : — The tin should dissolve 
 in pure hydrochloric acid without leaving a black powdery residue. If such 
 residue appear it should be well washed in distilled water, dissolved in nitric 
 acid, freed from excess of acid by evaporation, and mixed with an excess of 
 ammonia. A blue tinge indicates the presence of copper. 
 
 For the detection of arsenic and antimony a few fragments of the sus- 
 pected metal are placed in a Marsh's apparatus, and dissolved in pure hydro- 
 chloric or dilute sulphuric acid. The gas given off is burned at the jet, with 
 the precautions indicated in treatises on qualitative chemical analysis, and 
 fragments of white porcelain are held in the flame. If shining metallic spots 
 are deposited on the porcelain, either arsenic or antimony or both must be 
 present. 
 
 As regards other impurities, a portion of the solution of the metal in pure 
 hydrochloric acid is saturated with sulphuretted hydrogen gas, a current of 
 which is passed into it as long as anything is deposited, and until the liquid 
 has a strong and permanent smell of the gas. The precipitate formed, which 
 may contain sulphurets (sulphides of tin, lead, copper, arsenic, and antimony), 
 is filtered off, and digested in hydrosulphate of ammonia containing an excess 
 of sulphur. Should any matter remain undissolved, which when dried and 
 heated does not volatilise, it is probably sulphide of lead. 
 
 If zinc and iron are present, they will be found in the liquid filtered from 
 the precipitate occasioned by the current of sulphuretted hydrogen. This 
 filtrate is concentrated by evaporation to a small bulk, heated with nitric acid, 
 and, after the excess of the acid has been expelled, it is mixed with ammonia. 
 If iron is present it will be deposited as hydrated peroxide, of a reddish-brown 
 colour. This is removed by filtration, and the residual liquid, after further 
 concentration, is mixed with a solution of perfectly pure carbonate of soda. 
 A white precipitate shows the presence of zinc. 
 
 Or the liquid as filtered from the precipitate obtained by sulphuretted 
 hydrogen is mixed with hydrosulphate of ammonia. If any precipitate of 
 fixed matter is obtained the tin contains iron, zinc, or some metal of the same 
 class. 
 
 Hydrochloric acid, or, as it is still called, muriatic acid or " spirts of salts," 
 
MORDANTS. 
 
 521 
 
 is generally sold to dyers and printers at about 32 Tw. = sp. gr. r6o. When 
 diluted with distilled water and mixed with a small quantity of a weak 
 solution of chloride of barium it should not give a white precipitate or tur- 
 bidity. If such appears the sample contains sulphuric acid, either from 
 slovenly preparation or from design, and should be rejected. If a few par- 
 ticles of granulated tin are put in a test-glass and covered with the acid the 
 gas given off should be free from the odour of sulphuretted hydrogen, and 
 the resulting liquid should be clear, not yellowish or turbid. In the latter 
 case the sample is contaminated with sulphurous acid, a very common im- 
 purity when the manufacture is not conducted with due care. 
 
 An ounce of the acid should be placed in a small porcelain capsule, and 
 evaporated to dryness at a gentle heat. If pure nothing will remain behind. 
 If, as is sometimes the case, common salt has been added to raise the specific 
 gravity of a weak acid, a saline residue will be left in the capsule. To detect 
 arsenical compounds a few fragments of absolutely pure zinc are placed in a 
 Marsh's apparatus, and covered with the suspected acid previously let down 
 to one-half its strength with distilled water. The gas generated is then 
 burned at the jet as directed in testing tin for arsenic. 
 
 Nitric acid, or, as it is technically still called, aquafortis, is sold for the pre- 
 paration of mordants at two strengths. Double aquafortis varies in specific 
 gravity, from 64 to 66° Tw., about 1/50 to 1/56. It maybe tested for sulphuric 
 acid, for saline matter, and for arsenical compounds, in the same way as 
 directed for hydrochloric acid. In testing for arsenic, it should be previously 
 diluted with four or five times its volume of water. Sulphurous acid is not 
 likely to be present. Nitrate of soda is a not unfrequent adulterant. The 
 action of nitric acid in dissolving metals is greatly modified by the presence of 
 hyponitric and nitrous acids. These impurities may be removed by the 
 addition of peroxide of lead or red-lead. Either of these bodies gives off 
 oxygen, so as to convert the lower oxides of nitrogen into nitric acid, whilst 
 the lead does not dissolve. The nitrous acid is, however, liable to be repro- 
 duced if the stock is left exposed to the light, especially to direct sunshine. 
 
 The so-called " single aquafortis," or dyers' aquafortis, is a quite peculiar 
 preparation. Its strength is generally 32 or 33 Tw. It is absolutely free 
 from sulphuric acid and from the lower oxides of nitrogen. To free it from 
 this impurity various expedients are adopted at different establishments. 
 Sometimes it is exposed to the air for several weeks in a cool dark place. 
 Others cause it to trickle in a thin stream down stone-ware channels filled 
 with clean quartz pebbles. In one large chemical-works, in Yorkshire, men 
 are actually set to pour the acid from one receiver to another. Elsewhere a 
 stream of cold air is forced through the tanks of acid, which has the effect of 
 causing the nitrous and hyponitric acid to be expelled. Single aquafortis 
 contains a certain amount either of hydrochloric acid or of an alkaline 
 chloride. This is not to be viewed in the light of an adulteration, since 
 without it the aquafortis would not answer its purpose in the preparation of 
 " scarlet spirits." 
 
 Sulphuric acid, commonly known as oil of vitriol, or simply " oil," is gene- 
 rally bought for mordant-making as " double oil of vitriol," — the strongest 
 quality of acid which can be obtained by the ordinary process. It stands at 
 169 to 170° Tw. A variety of impurities may be present, which interfere 
 
522 
 
 DYEING AND CALICO PRINTING. 
 
 more or less seriously with the uses of this acid. Arsenious acid, which is 
 often present, is detected by means of Marsh's apparatus, as directed for 
 hvdrochloric acid, the sulphuric acid being previously diluted with ten times 
 its volume of water. Nitric oxide or other nitrogen compounds are also 
 common, and may be detected by putting a little of the suspected sample in a 
 test-glass, and dropping into it a clean fragment of the protosulphate of iron 
 (copperas). If a trace of nitric oxide be present, a slight reddish-brown 
 colouration will appear in the liquid, and will become by degrees more intense. 
 Dry sulphate of soda (salt-cake) is sometimes added to increase the apparent 
 strength of diluted acids. To detect it a portion of the acid is evaporated to 
 dryness, when sulphate of soda, if present, remains behind. 
 
 The purity of the water is far from being an unimportant point. Rain- 
 water, condensed steam-water, or the surface drainage of uncultivated moor- 
 lands, should be selected. Well- and river-waters, holding in solution lime, 
 magnesia, iron, or alumina, may produce serious mischief. 
 
 It must not, however, be supposed that purity of ingredients and strict 
 attention to the proportions laid down in approved receipts will suffice to pro- 
 duce satisfactory results. The initial temperature, the order in which the 
 materials are mixed, the speed at which the operation progresses, and the 
 higher or lower degree of heat obtained in the process, — all modify the result. 
 It is very easy to find two samples of a tin solution made with the same ma- 
 terials in the same proportions, yet where the one gives an excellent result 
 the other is practically worthless, having affinity neither for the fibre nor for 
 the colour. 
 
 I. Proto-Salts of Tin and their Solutions. 
 Protochloride of tin, or stannous chloride, unmixed with any other body, 
 is used in dyeing and printing in various forms. These are tin-crystals, 
 sometimes called tin-salt, or salts of tin ; double muriate and single 
 muriate. The preparation of these compounds is very simple. To obtain 
 tin-crystals, hydrochloric acid, at 32° Tw., is allowed to act upon an excess 
 of feathered tin, with the aid of heat. The operation is generally per- 
 formed in large stone-ware vessels, heated by means of a water- or steam- 
 bath, and fitted with covers to prevent needless waste of hydrochloric 
 acid vapours, whilst allowing the hydrogen gas generated to escape. Some 
 chemists use copper vessels for this purpose, which, so long as any tin remains 
 undissolved, are not in the slightest affected by the acid. A very common 
 arrangement is to effect the solution in a series of large three-necked receivers, 
 connected together by stone-ware pipes, so that any acid escaping from the 
 first receiver is caught and utilised in the next. The most economical arrange- 
 ment on the large scale is that devised by Noellner, who places the feathered 
 tin in stone-ware cylinders, allows water to trickle down through the mass 
 from above, and drives in from below hydrochloric acid gas as it issues from 
 the ordinary retorts in which it is generated. The saturated solution of tin, 
 however obtained, is rapidly evaporated down, during which process some fresh 
 granulated tin must be constantly kept in the liquid, otherwise oxychloride and 
 bichloride of tin will be formed, and the properties of the preparation will be 
 modified. The liquid, when sufficiently concentrated, is drawn off, and allowed 
 to crystallise. 
 
 The crystals, which should contain 52 per cent of metallic tin, are white, 
 
MORDANTS. 
 
 523 
 
 silky, dry, and smooth to the touch. They should dissolve in ten times their 
 weight of distilled water, without turbidity, and if a few drops of pure hydro- 
 chloric acid be added no turbidity or precipitate should appear on the further 
 addition of a solution of chloride of barium. If a white cloud or deposit is 
 produced, sulphate of zinc, sulphate of magnesia, or some other sulphate, is 
 present as an adulterant. 
 
 Chloride of zinc is also sometimes present. In such cases the sample 
 grows damp on exposure to the atmosphere, more rapidly than do genuine 
 crystals. To ascertain its absence a sample of the crystals should be dissolved 
 in water, with the addition of a few drops of hydrochloric acid. A current of 
 sulphuretted hydrogen is next passed through the liquid until it is fully satu- 
 rated. The precipitate produced by this means is filtered off, and the filtrate 
 evaporated down to dryness. If the sample was genuine no fixed residue will 
 remain after exposure to a red heat. Should a fixed residue be found, then, if 
 no sulphuric acid can be detected in the crystals, the presence of chloride of 
 zinc is highly probable. 
 
 If it is required to find the amount of metallic tin present in a sample of 
 tin crystals, or in any solution in which this metal is present as a proto-salt, 
 the following volumetric method can be recommended : — 
 
 A standard solution of tin is first prepared, by dissolving, in pure hydro- 
 chloric acid, exadtly 500 grains of pure tin. The solution is then made up 
 with distilled water to the exacl volume of 20 ounces. 
 
 A solution of iodine is next prepared in the following manner: — 127 grs. of 
 pure iodine and 180 grs. of pure iodide of potassium are weighed out and dis- 
 solved in 10,000 grain-measures of water, without the aid of heat. This 
 solution is preserved in small, well-stoppered bottles. The iodine solution is 
 next standardised. For this purpose such a portion of the standard tin liquid 
 is measured off as may contain exactly 2 or 4 grs. of metallic tin. It is put 
 in a beaker, and mixed with bicarbonate of soda in excess, along with double 
 tartrate of potash and sqda sufficient to keep the liquid bright. A little 
 starch-liquid is then added, and the iodised solution is allowed to drop in from 
 a burette until a permanent, though faint, blue tint appears in the glass. The 
 number of degrees of the burette consumed indicate what measure of the 
 iodine solution represents 1 gr. of tin. A known quantity — say 5 grs. — of the 
 tin-crystals under examination must next be weighed out and dissolved in 
 water, with the addition of a very little hydrochloric acid. Bicarbonate of 
 soda and the double tartrate are then added as before. The starch-liquid 
 follows, and the iodine solution is then dropped in, as above, till a faint blue 
 tint makes its appearance. The amount of tin present in the crystals can 
 then be easily calculated. 
 
 Double Muriate of Tin is often the subject of a misunderstanding. Some 
 writers conceive that it is a bichloride or per-salt of tin. This is an error. 
 After examining hundreds of samples from different makers, and as used in 
 different establishments, we can affirm that it is a proto-salt of tin, differing 
 from single muriate merely by being stronger and having a higher specific 
 gravity, just as is the case with " double oil of vitriol " as compared with 
 " single." Double muriate of tin ranges in specific gravity from 70 s to 
 120° Tw., and contains from 2J to 5 ounces of metallic tin to the pound of 
 liquid. It is made in the same manner as tin-crystals, with the only difference 
 
■■■PI 
 
 RHHSBBE 
 
 524 
 
 DYEING AND CALICO PRINTING. 
 
 that the liquid is bottled off when the required strength has been reached 
 without pushing it on to crystallisation. Some makers, instead of applying 
 heat to promote the action of the hydrochloric acid upon the mass of feathered 
 tin, pour on the acid, and after a few minutes run it off upon another similar 
 quantity of tin. In a short time it is returned to the first lot, and by this 
 alternating action the temperature is raised and the tin dissolved much more 
 rapidly than if the acid were allowed to act without intermission upon one 
 quantity of tin. In some establishments it is customary to use the hydro- 
 chloric acid at the strength of 32 Tw., whilst in others it is diluted with more 
 or less water before being allowed to act upon the tin. In consequence, two 
 samples of genuine double muriate, of the same specific gravity, but from 
 different makers, may contain unlike amounts of tin. The lower the initial 
 strength of the acid, the more metal must have been dissolved to raise the 
 specific gravity to any given point. 
 
 Double muriate is frequently adulterated with sulphuric acid, sulphates of 
 zinc and magnesia, chloride of zinc, &c. The price at which many samples 
 are offered is in itself a sufficient proof of sophistication, being frequently 
 less than the market-price of the tin which ought to be present in the genuine 
 article. Few samples are met with which do not contain sulphuric acid in 
 larger amount than can be accounted for by the possible presence of a little of 
 this body as an impurity in the hydrochloric acid used. 
 
 The methods for detecting these various sophistications have been indicated 
 above. The weaker double muriates, from 70 to 90 Tw., are used by the 
 woollen-dyers; the stronger, at no to 120 , are applied to cotton, which is 
 less able to resist the action of acids. 
 
 Single Muriate of Tin is comparatively little used. Its specific gravity 
 ranges from 40 to 6o° Tw., and its proportion of metallic tin varies from 1 to 
 2 ounces per lb. It is chiefly employed in wool-dyeing. 
 
 II. Solutions of Proto-Salts of Tin, in which other Acids are used along with 
 the Hydrochloric. 
 
 Old Scarlet Spirit (Dr. Bancroft's). 
 
 Mix — Oil of vitriol 2 lbs. 
 
 Hydrochloric acid, at 32 Tw 3 ,, 
 
 And dissolve in the mixture- 
 Tin 14 ozs. 
 
 This spirit was, as its name implies, formerly used for lac and grain scarlets 
 upon woollen and worsted goods. It is now little used, as the scarlets produced 
 by its means are apt to exhibit a brownish shade. 
 
 Amaranth Spirit. 
 
 Mix — Hydrochloric acid, at 32 Tw 95 lbs. 
 
 Oil of vitriol 5 ,, 
 
 And dissolve — 
 
 Tin 4 ,, 11 ozs. 
 
 This spirit is greatly recommended by some woollen-dyers for producing 
 reddish-violet and purple shades with the woods. 
 

 MORDANTS. 
 
 525 
 
 Yellow and Orange Spirit. 
 
 Double muriate, at So' Tw 5 lbs. nozs. 
 
 Mix — Oil of vitriol 2 ,, 
 
 Water .. 2 ,, 
 
 And when cool add the mixture to the double muriate. The more tin and the 
 less free acid occur in the double muriate, the more the cloth will exhibit a 
 beautiful greenish reflection if it be held up to the light, and the eye directed 
 horizontally along its surface. 
 
 Another Yellow Spirit. 
 Hydrochloric acid, 3 parts ; sulphuric acid, 1 part ; water, 1 part ; as much 
 feathered tin as it will take up. The heat should not rise above 6o° F. 
 
 Scarlet Finishing Spirit. 
 Take 3 pints muriate of tin, at 54 T\v. ; 
 
 2 ozs. oxalic acid, dissolved in hot water sufficient to reduce the whole 
 to 40 Tw. 
 This spirit, as its name implies, is used for " raising " or finishing grain scar- 
 lets which have been begun with the " bowl- spirit " or "scarlet spirit" 
 described below, under the sesqui-salts of tin. It gives extreme fire and 
 brilliance. Some dyers consider that a richer and mellower shade is obtained 
 if half the oxalic acid above specified is replaced with tartaric. In some 
 establishments this spirit is used at once along with grain or lac, without the 
 preliminary application of the " scarlet spirit." This is especially the case 
 when hard worsted trimmings have to be dyed. In such cases it is used 
 without tartar. For softer goods it is better to increase the strength of the 
 muriate of tin up to 6o° or even 70 Tw. This is especially recommended 
 for grain orange, maize, and similar shades. 
 
 Another Scarlet Finishing Spirit. 
 Take 16 quarts muriate of tin, at 54° Tw. : 
 1 pint oil of vitriol : 
 3 lbs. water. 
 The sulphuric acid and water are mixed, allowed to cool, and then added to 
 the muriate of tin : 1 lb. oxalic acid is next dissolved in 10 lbs. water, and the 
 solution is added to the other ingredients. When this spirit is used from the 
 commencement in scarlet-dyeing, and not merely for finishing, tartar is 
 required in the ordinary proportions. 
 
 Purple, Plum, or Puce Spirit. 
 
 Take good muriate of tin, at 70 Tw 2 gals. 
 
 Mix sulphuric acid and water till the mixture stands at 28 Tw.] 
 
 When cool add of this \ x S aK 
 
 And stir well. 
 
 Oxalate of Tin.— This name is very improperly used. A real oxalate of 
 tin can scarcely be said to be known in commerce, but all mixtures of muriate 
 of tin with oxalic acid, and with or without sulphuric acid, are sold under this 
 name, often abbreviated into " Ox. Tin.'' 
 

 iwmw 
 
 526 DYEING AND CALICO PRINTING. 
 
 One of the most useful of these mixtures may be made by taking the above- 
 mentioned purple spirit, and adding to it 1 ounce of oxalic acid, previously 
 dissolved in hot water, for every gallon. This oxalate of tin will then serve 
 for finishing royal blues, for putting a top bloom on blacks, as a scarlet spirit 
 with grain or lac, and as an orange spirit with mixtures of grain and flavin, 
 young fustic, &c. If greater brightness is required, in case of scarlets or 
 royal blues, the proportion of oxalic acid may be raised from 1 ounce to 
 i£ or 2 ounces per gallon. Such increase of oxalic acid is not recommended 
 for topping blacks. This oxalate of tin makes the nearest approach to a 
 universal spirit for wool-dyeing. 
 
 The following are oxalates of tin all in actual use : — 
 
 a. Muriate of tin, at 8o° Tw 6 gals. 
 
 Sulphuric acid, at 42 Tw 3 ,, 
 
 Oxalic acid 2 ounces per gallon. 
 
 b. Muriate of tin, at 76 Tw 6 gals. 
 
 Sulphuric acid, at 42° Tw 4 ,, 
 
 Oxalic acid 2 ounces per gallon. 
 
 c. Muriate of tin, at 70 Tw 6 gals. 
 
 Sulphuric acid, at 40° Tw 4 ,, 
 
 Oxalic acid 2 ounces per gallon. 
 
 Claret Spirit. 
 
 The bluest shades are produced by a pure muriate of tin, made by mixing 
 3 parts by measure of hydrochloric acid, at 32 Tw., with 1 part of water, and 
 saturating it with tin up to 48° to 50 Tw. If to be used in rag-dyeing, for 
 the conversion of blacks into clarets, 10 per cent of a solution of common 
 salt in water, at 32 Tw., may be usefully added. The sulphuric acid which 
 the rag-dyer uses will decompose the salt, forming sulphate of soda, while the 
 hydrochloric acid liberated will aid in discharging the blacks. If redder 01 
 browner clarets are in request, there may be added to the muriate of tin from 
 j'gth to T ' th by measure of dilute sulphuric acid, at 28° Tw. 
 
 The Chlorostannite of Ammonium, a compound of stannous chloride 
 (protochloride of tin) and chloride of ammonium (sal-ammoniac), is prepared 
 by heating tin-dust with sal-ammoniac. It forms regular octahedral crystals, 
 which dissolve in water, the solution becoming turbid on boiling. Its uses 
 have been merely experimental. 
 
 The Stannite of Soda is a compound in which stannous oxide — the protoxide 
 of tin — plays the part of an acid. It is formed by dissolving the precipitated 
 hydrate of stannous oxide in a solution of caustic soda to saturation, and 
 preserving the product, as far as possible, from contact with the air. It is at 
 present rarely used. 
 
 III. Sesqui-Salts of Tin. 
 The sesqui-salts of tin ar,e much less used, and even much less known, than 
 either the proto- or the per-salts. They may be distinguished by their colour, 
 which is of a peculiar deep amber or brownish-yellow. At low temperatures 
 they are moderately permanent, but at an ordinary summer heat they are 
 decomposed in about twenty-four hours. The best known compound of this 
 class is — 
 
MORDANTS. 
 
 527 
 
 Nitrate of Tin, called also, from its principal use, " Scarlet Spirits" and 
 " Bowl-Spirits," because prepared in large stone-ware bowls. The name 
 nitrate of tin, it must be remembered, is applied in some districts to per-salts 
 of tin prepared with mixtures of nitric and hydrochloric acid, in which the 
 latter largely predominates. The name, however, in the woollen regions of 
 Yorkshire, and especially in the Halifax and Bradford districts, is exclusively 
 applied to the compound we are now describing. Its preparation is a matter 
 of some nicety. A known quantity of the liquid which we have mentioned 
 above under the name of single aquafortis, or dyers' aquafortis, standing at 
 32° Tw., is placed in a capacious and perfectly clean bowl, and the finest grain- 
 bar tin, in the rod, i.e., not feathered, is dissolved therein, in the proportion of 
 I lb. of metal to 8 lbs. of the acid. The number of rods put in at first is varied, 
 according to the temperature and the make of the acid. If the weather be neither 
 hot nor cold, and the acid of an average quality, some four or five rods are placed 
 in each bowl, and allowed gradually to dissolve. After a time, if the operation 
 is successful, the liquid is said to " turn," — that is, to assume a deep amber or 
 orange colour. When this point is once attained, all that is required is to 
 feed in by degrees the remainder of the tin that has been weighed out, taking 
 care that the action neither dies out from want of material nor becomes too 
 fierce. No bubbles of red- or orange-coloured gas ought to be formed. If the 
 process is unsuccessful, the liquid will sometimes remain colourless, like 
 water, for two or three hours, and then suddenly become thick and turbid, 
 without development of the amber colour. Under other circumstances, espe- 
 cially if too much tin has been added at the outset, orange-coloured fumes of 
 nitric oxide are thrown off, and the tin, instead of dissolving, is deposited in 
 an insoluble condition. In these cases the spirit is said to have " turned its 
 back " on the operator, and is hopelessly spoiled. In cold weather as many 
 as eight or ten rods may be entered at once without fear of accident; but 
 when the temperature is high, two, or even one, may be quite sufficient, and 
 it is sometimes needful to keep down the action by placing the bowl in a 
 current of cold water. Sometimes, in hot weather, this spirit may be advan- 
 tageously started with a small handful of clean, dry, feathered tin ; rods being 
 afterwards gradually added, when the spirit is once fairly in course of forma- 
 tion. The operation is greatly facilitated if, at the outset, half a pint of 
 nitrate of tin, from a former making, is added to the aquafortis. 
 
 If properly made this spirit is a deep amber liquid, of from 58 to 66° Tw., 
 and contains about 2i ounces of metallic tin to the pound. It is not an article 
 of commerce, being always made on the spot on account of its instability. On 
 long standing it deposits its tin in a yellowish gelatinous mass, and becomes 
 unfit for use. 
 
 Curiously enough, some persons have denied the very existence of this 
 preparation, though known and used in every dye-house in Yorkshire where 
 cochineal shades are produced. Almost the only author who admits its 
 existence is J. Ordway (" Chemical Gazette "). 
 
 Nitrate of tin- is chiefly used for grounding scarlets and other cochineal 
 shades upon wool and worsted goods of all kinds. It is sometimes also 
 employed in cotton-dyeing, especially for the cotton warps of coburgs, 
 delaines, and other mixed goods. 
 

 528 
 
 DYEING AND CALICO PRINTING. 
 
 Purple Spirit for Wool and Worsted. 
 
 The following spirit is used in producing certain purples with mixtures of 
 logwood and the red woods : — 
 
 Take common nitrate of tin, which should be well made and recent. Warm 
 it gently, by setting the bowl containing it in a larger cistern or vessel of hot 
 water, and add as much grain-bar tin, in the rod, as it will take up. It should 
 mark about 80° Tw. 
 
 So-called " Aniline Spirit," known also as " Nitro-muriate of Tin," — a 
 name which is promiscuously applied to the results of at least a hundred 
 different receipts having little in common, save that tin is dissolved in hydro- 
 chloric acid, to which more or less nitric acid has been added. 
 
 The mordant in question serves for working aniline colours upon the cotton 
 warps of mixed goods, and also for certain fine browns, clarets, maroons, &c, 
 produced with the woods. When well made this spirit gives very full, rich, 
 bloomy shades, 
 
 " Single aquafortis," at 32 Tw 5 gals. 
 
 Muriatic acid, at 32 Tw 2j „ 
 
 Grain-bar tin, not feathered 12 lbs. 
 
 Mix the acids, and enter about twelve rods at once, distributing them at 
 regular intervals around the sides of the bowl. As these dissolve make further 
 additions gradually, not letting the mixture get very hot. If the temperature 
 threatens to become excessive, some of the partially dissolved bars of tin may 
 be withdrawn from the liquid for a time, to moderate the adtion. If properly 
 worked it will be of a reddish or deep amber colour. This spirit contains 
 nearly 2 ounces tin to the lb. of acid. 
 
 The following receipts, of foreign origin, will, if carefully worked, yield 
 compounds of the sesquioxide of tin. 
 
 Hellot's Mordant. 
 
 Nitric acid (strength not given) 8 ozs. 
 
 Water 8 „ 
 
 Sal-ammoniac i oz. 
 
 Nitre 2 drachms 
 
 Tin, granulated 1 oz. 
 
 Another. 
 
 Nitric acid 1 lb. 
 
 Water r ,. 
 
 Sal-ammoniac ij ozs. 
 
 Tin 2 ,, 
 
 Another. 
 
 Nitric acid, at 30 Baume lib. 
 
 Sal-ammoniac 2 ozs. 
 
 Water 4 „ 
 
 Tin 4 ,, 
 
 Whenever sal-ammoniac (chloride of ammonium) is added to a mordant, a 
 certain amount of pink salt (see below) will be formed, and the result will 
 differ from that given by free hydrochloric acid or chloride of sodium in 
 equivalent amount. 
 
MORDANTS. 
 
 529 
 
 IV. Stannic Salts, or Per-Salts of Tin. 
 
 These compounds, very extensively used in cotton- and silk-dyeing and in 
 printing, are composed of the peroxide (binoxide or tetroxide) of tin, united 
 with various acids, and of the stannic chloride or perchloride of tin. They 
 are produced in a variety of ways, sometimes directly from the metal, and at 
 other times by the oxidation of the proto-salts of tin, whether by means of 
 free chlorine or of nitric acid. 
 
 The making of these preparations is a matter requiring much care, especially 
 in all those processes where a mixture of nitric and hydrochloric acids is 
 allowed to ad upon the metal or upon proto-salts. According to the temper- 
 ature employed and the speed at which the operation has been conducted, two 
 lots, composed of the same materials, may contain very different proportions 
 of protoxide and peroxide. The result may be in one case a perfect peroxide, 
 whilst in another the proto-salt may largely predominate. Such varying com- 
 pounds yield, of course with the same dye-wares, different shades of colour, 
 to the great discomfiture of the dyer, who, using what he supposes to be iden- 
 tical materials, finds ever-fluctuating results. The condition or state of 
 oxidation of a sample may be very easily detected. If to a little of the spirit 
 placed in a test-glass we add a few drops of a solution of mercuric chloride 
 (corrosive sublimate) in water, then, if any of the tin was present in the state 
 of a proto-salt, a white turbidity is formed, which speedily blackens. If the 
 tin be a pure per-salt there will be no apparent action. 
 
 But whilst the process should be brisk enough to ensure the formation of a 
 perfect per-salt, as the only way to secure constant results, too rapid an action, 
 and a consequently excessive temperature, can occasion serious mischief. 
 The tin, in great part or entirely, instead of becoming dissolved, may be depo- 
 sited at the bottom of the vessel as an insoluble peroxide. This result, known 
 as " firing," is common in careless or inexperienced hands. 
 
 But without precipitating the tin in this insoluble state, its affinity for the 
 fibre may be destroyed by a small excess in temperature. A spirit thus 
 spoiled, if compared with one of the same class and made from the same 
 materials, but in proper condition, shows no tangible difference. They, too, agree 
 in specific gravity, colour, smell, in degree of acidity, and in the amount of 
 tin contained ; yet the one attaches itself readily to the fibre, which then, in 
 contact with the colouring matter, dyes up a full shade ; the other, similarly 
 treated, yields merely an irregular and impoverished stain. It would seem, in 
 consequence, that the per-salts of tin may exist in at least three different 
 states, in one only of which they have a marked affinity for animal and 
 vegetable fibres, and can be, by them, withdrawn from solution. 
 
 The acids present along with the per-salts of tin are chiefly the nitric and 
 hydrochloric ; the sulphuric is rarely used. Oxalic acid is also less frequently 
 added than with the protosalts of tin. Alkaline chlorides and nitrates are not 
 unfrequently present, and have modifying effects, especially the chloride of 
 ammonium (sal-ammoniac), which forms with the stannic chloride a definite 
 compound, to which we shall return below. The nitric acid used in preparing 
 these compounds, except where otherwise specified, is the " double aqua- 
 fortis " of commerce, of about 64 to 65 Tw. The tin is generally used not 
 feathered or granulated, but in the rod. 
 

 530 
 
 DYEING AND CALICO PRINTING. 
 
 Bichloride, Perchloride, or Tetrachloride of Tin, Stannic Chloride, 
 Chlorostannic Acid, or Fuming Spirit of Libavius. — This compound, 
 in its dry or anhydrous state, is used, not as a mordant, but in the preparation 
 of one form of magenta. It may be obtained by slowly passing chlorine gas 
 into a retort containing tin-foil or melted tin. The compound, as formed, 
 distils over into a receiver, which is kept carefully cooled. It may also be 
 obtained by distilling i part by weight of tin with 5 parts of mercuric chloride, 
 or by distilling dry common salt with dry stannic sulphate (persulphate of tin) 
 in an iron retort, raising the heat as long as anything passes over. It is a 
 thin colourless liquid, which gives off dense white fumes on exposure to 
 the air. 
 
 Aqueous Bichloride, or Stannic Chloride of Tin, known in some dis- 
 tricts as " Scarlet Spirits," in others as " Dyers' Composition," and as 
 " Hydrochlorate of Stannic Oxide," is made in a variety of manners, indicated 
 above. Sometimes a double muriate of tin, at 120 Tw., or upwards, is satu- 
 rated with chlorine gas, prepared by gently heating black oxide of manganese 
 in hydrochloric acid. Some makers heat tin crystals to which a quantity of 
 hydrochloric acid has been added, with nitric acid introduced by portions, care- 
 fully avoiding excess. Or the metal itself is dissolved in aqua-regia, avoiding 
 excess of nitric acid, and conducting the process slowly. Nitric acid, when used 
 in this manner, either along with tin-crystals or with the metal, is never entirely 
 driven off. Whenever, consequently, bichloride or perchloride of tin, or hydrated 
 stannic chloride, or " composition," is directed to be used, either alone or as 
 one ingredient in a compound mordant, the article to be employed is that pre- 
 pared by the adtion of chlorine gas upon tin-crystals or double muriate of 
 tin. The chlorine should be allowed to a<5t until a portion no longer gives 
 the above-mentioned precipitate with a solution of corrosive sublimate. 
 This pure aqueous perchloride of tin, either with or without the addition 
 of oxalic acid, may be used for dying cochineal or lac scarlets with satis- 
 factory results. 
 
 I. Red Cotton Spirits, known also as Crimson Spirits. 
 
 Muriatic acid, at 32 to 34 Tw 7 gals. 
 
 Nitric acid (double aquafortis), at 64 Tw 1 gal. 
 
 Water «. 1 ,, 
 
 Mix these liquids thoroughly, and when they have stood for a few minutes 
 enter the tin, 6 lbs. of which have been weighed out for the above quantity of 
 acid, as follows : — Put in about six rods, upright, at equal distances around 
 the sides of the bowl, and as they dissolve add the rest by degrees. 
 It must never get hot enough to give off orange vapours. If the weather 
 is very cold, eight or ten bars may be put in at first. In eight or nine 
 hours all the tin will be dissolved. Never stir it whilst working. When 
 finished it should be clear, and of a very pale straw-colour. In cold weather, 
 the water mixed with the acids may be reduced to 3, 2, or 1 quart, or omitted 
 altogether. This spirit is recommended for reds, crimsons, scarlets, clarets, 
 browns, and sometimes drabs, upon cotton-yarns; and for reds, crimsons, and 
 scarlets, upon the cotton-warps of mixed piece-goods. 
 
MORDANTS. 531 
 
 2. Red Cotton Spirit. 
 
 Hydrochloric acid, as before 6 gals. 
 
 Nitric acid 1 gal. 
 
 Water 1 „ 
 
 Tin 6 lbs. 
 
 Work as before. This spirit is more adapted for the cotton-warps of clarets 
 and browns. 
 
 3. Red Cotton Spirit. 
 
 Hydrochloric acid, at 32 Tw 6 gals. 
 
 Nitric acid, at 64 Tw 2 ,, 
 
 Tin 10 lbs. 
 
 Work as above. 
 
 4. Red Cotton Spirit. 
 
 Hydrochloric acid, at 35 Tw 8J gals. 
 
 Nitric acid, at 64 Tw ij ,, 
 
 Tin sufficient to bring up the specific gravity to 54° Tw. 
 Bichromate of potash 1 oz. 
 
 5. Red Cotton Spirit. 
 
 Hydrochloric acid, at 32° Tw 3 gals. 
 
 Nitric acid, at 64° Tw 1 gal. 
 
 Water 1 ,, 
 
 Tin, 2 ozs. per lb. of the mixed acid. 
 
 In this case, exceptionally, the tin is not used in the bar, but granulated, and 
 added in very small quantities at a time. 
 
 6. Red Cotton Spirit. 
 
 Hydrochloric acid, at 32 Tw 6 gals. 
 
 Nitric acid, at 64° Tw r gal. 
 
 Tin, grain-bar 10 lbs. 
 
 Barwood Spirit. 
 
 Hydrochloric acid, at 32 Tw 5 gals. 
 
 Nitric acid, at 64 Tw 1 gal. 
 
 Tin, 1 oz. per lb. of mixed acids. 
 
 Plum Spirit. 
 
 Hydrochloric acid, as above 6 gals. 
 
 Nitric acid, as above 1 gal. 
 
 Tin, i£ ozs. per lb. of mixed acids 
 Pink Spirit, with peach-wood or cotton ; see " Yellow Spirit." 
 
 " Solution of Tin." 
 These preparations, called often simply " Solution," are used for similar 
 purposes to red cotton spirits. They are generally a little stronger. 
 
 Hydrochloric acid at 32 Tw 6 gals. 
 
 Nitric acid at 64° Tw 1 1 gals. 
 
 Water I gal. 
 
 Tin, in rods 7 lbs. 
 
 2 M 3 
 
i>JU»si<*i. J yX'- 
 
 ■BBBBBBBBBBBB 
 
 532 DYEING AND CALICO PRINTING. 
 
 Work in the same manner as directed for red cotton spirits. Let the action 
 be brisk, and the surface of the liquid be covered with fine froth, but no orange 
 vapours must lise. 
 
 This preparation is strongly recommended for the cotton warps of clarets, 
 maroons, browns, &c. 
 
 No. 2 Solution. 
 
 Hydrochloric acid at 32 Tw 6 gals. 
 
 Single aquafortis at 32 Tw 3 gals. 
 
 Tin, in rods ioj lbs. 
 
 Work gradually. Much recommended for similar purposes, and for drawing 
 aniline colours upon cotton warps. 
 
 Purple Cotton Spirit. 
 
 Hydrochloric acid k 'as above) 5 lbs. 
 
 Nitric acid (as above) 1 lb. 
 
 Tin, 2 ozs. per lb. of acid. 
 When dissolved add 4 ozs. of bichromate of potassa, previously dissolved in 
 water, to every 18 gals, of the spirit. 
 
 Oxymuriate of Tin. 
 
 Hydrochloric acid 20 lbs. 
 
 Nitric acid 20 lbs. 
 
 In which latter 5 lbs. sal-ammoniac have been dissolved. Then work in — 
 Tin 10 lbs. 
 
 Ditto, No. 2. 
 Melt 16 lbs. tin crystals in a bowl set in a tank of hot water, and add 
 gradually nitric acid, 20 lbs. 
 
 Ditto, No. 3. 
 Melt 60 lbs. tin crystals and 1 quart water by the heat of a water-bath. 
 Then add by degrees 92 lbs. nitric acid at 6o° Tw. 
 
 Ditto, No. 4. 
 
 Hydrochloric acid at 34 Tw 11 lbs. 
 
 Nitric acid at 62° Tw 5 lbs. 
 
 Add gradually 2 lbs. feathered tin. 
 
 These oxymuriates are chiefly used by printers. The second is used for 
 11 cutting" madder pinks, and the fourth for spirit colours. 
 
 Pink Salt is a compound of stannic chloride (perchloride of tin) with 
 chloride of ammonium. On mixing concentrated solutions of its two con- 
 stituents it falls as a white powder. In many cases it is not used preformed, but 
 its constituents are separately added to a colour. Pink salt has the power of 
 dissolving a great number of organic colouring matters, and its applications 
 in the tinctorial arts will doubtless become more numerous. 
 
 The peroxide of tin is also capable of playing the part of an acid. In this 
 state it is called stannic acid, and forms stannate of soda, otherwise known 
 as "preparing salt." It is sometimes made as wanted by adding a saturated 
 
MORDANTS. 
 
 533 
 
 lye of caustic soda to a concentrated solution of perchloride of tin till the pre- 
 cipitate which falls at first is all re-dissolved. It is then, of course, mixed 
 with the chloride of sodium. It may also be prepared in the dry way. 
 Greenwood and Mercer obtain it by taking 22 lbs. of caustic soda (1 gallon 
 weighing 13J lbs.), and putting it in an iron crucible heated to low redness by 
 a fire under it. When watery vapours cease to come off they add 8 lbs. 
 nitrate of soda and 4 lbs. of common salt. When the whole is at or near the 
 point of fusion 10 lbs. of feathered block tin are added and stirred with an 
 iron rod until deflagration takes place, and the mass becomes fully red hot 
 and of a pasty consistence. It may be purified by dissolving it, when cold, in 
 water, allowing impurities to settle, decanting off the clear liquids, and 
 evaporating it down to near dryness. 
 
 Young heats finely ground tin ore of good quality along with caustic soda 
 to about 600° F. ; or with nitrate and muriate of soda (common salt), a current 
 of steam being passed at the same time over the mass. Purification by 
 solution in water and settling, and subsequent decantation and boiling down 
 are here necessary. 
 
 Haeffely places in an iron pan litharge or red-lead (or hydrated peroxide of 
 iron, hydrated peroxide of manganese, manganate of soda, indigo, &c.) and a 
 solution of caustic soda containing 22 per cent of alkali. A plumbate or 
 plumbite of soda is thus formed, heat being applied to hasten the process, and 
 the air being as far as possible excluded. Feathered tin is then suspended or 
 thrown into the liquid, when it dissolves, forming stannate of soda, whilst 
 metallic lead is thrown down in a spongy state. The proportions are — 16 lbs. 
 tin, 45 lbs. caustic soda at 70 Tw., and 70 to 80 of litharge, or 54 lbs. of red- 
 lead. When the tin is perfectly dissolved, which may require four to five 
 hours boiling, the fire is withdrawn, and the sediment allowed to settle, and 
 the clear liquid is decanted, and is ready for use. The deposit of spongy lead 
 may be re-converted into litharge or red-lead by prolonged exposure to the 
 air at a heat just below redness, and may be then used for another operation. 
 
 To ascertain the amount of tin present in a commercial sample of stannate, 
 a small portion is dissolved in water, to which a few drops of hydrochloric 
 acid have been added, and a few pieces of sheet zinc, pure and clean, are placed 
 in the mixture. The tin is thus precipitated in a spongy metallic state. It is 
 collected, washed with distilled water, re-dissolved in pure hydrochloric acid, 
 and its amount is determined as explained above. 
 
 Some dyers and printers believe that they can ascertain the value of a 
 stannate by dissolving a known weight in a fixed measure of water, and noting 
 its specific gravity as shown on Twaddle's hydrometer. This test is quite 
 fallacious, since an adulterated article will raise the specific gravity of water 
 as well as one of the best quality. Manufacturers of spurious chemicals are, 
 as a rule, inclined to appeal to the hydrometer as a test of value. 
 
 Stannate of soda may contain an excess of alkali as well as silica, &c, from 
 careless workmanship, and it may be intentionally sophisticated with common 
 salt. The percentage of water in a hydrated or crystalline stannate is from 
 20 to 27 per cent. Salt is sometimes present to the amount of 28 per cent. 
 
 Stannate of soda is used in printing to prepare the cloth for receiving the 
 so-called steam-colours. The calico is then passed through very dilute 
 
BBBBB 
 
 534 
 
 DYEING AND CALICO PRINTING. 
 
 sulphuric acid, which, combining with the alkali, leaves the stannic acid (oxide 
 of tin) deposited in the fibre. 
 
 In dyeing cotton yarn is extensively used for a variety of colours, especially 
 for the anilines. Its application to the warps of mixed piece goods requires 
 much caution. The sulphur present in the wool or worsted is very apt to 
 react upon tin presented in an alkaline solution, thus turning the fibre an un- 
 pleasant brownish colour. The only way of avoiding this mischief is to work 
 at the lowest possible temperature, to make the solution very dilute, and not 
 needlessly to prolong the mordanting process. 
 
 Some printers consider it advantageous to form double salts of the stannic 
 and some other acid, and to employ them in place of the ordinary stannales. 
 Mercer and Blyth patented the arsenio-stannates and phospho-stannates of 
 potash; soda, and ammonia. The arsenio-stannate of soda can be made by 
 dissolving i£ lbs. of the arseniate of soda in i gallon of stannate of soda 
 liquor at 50 Tw. The benefit to be derived from such admixtures or com- 
 pounds is somewhat doubtful. In 1852 James Higgin patented an alumino- 
 stannate to be used in place of the ordinary stannate. This alumino-stannate 
 is prepared by adding to stannate of soda in solution, aluminate of soda 
 also in solution, in such proportion that for every 14 lbs. of metallic tin in the 
 stannate there shall be 1 lb. of alumina. The patentee proposes also to add 
 chloride of aluminium to the chlorides of tin used in printing or d}'eing. 
 
 Silico-stannates have been used experimentally, but the results were 
 unsatisfactory. 
 
 Alumina Mordants. 
 Several compounds of aluminium are highly important as mordants. The 
 majority of these have been incidentally described in the foregoing chapters, 
 as potash-alum, ammonia-alum, sulphate of alumina, acetate of alumina, 
 nitrate of alumina, muriate of alumina (aluminic chloride) oxalate of alumina, 
 hyposulphite of alumina, &c. Tartrate of alumina is rarely used as such, 
 but it is formed in the dye-bath whenever alum and cream of tartar are used 
 together. 
 
 Aluminate of Soda, called also alkaline-pink mordant, was formerly pre- 
 pared when wanted by adding an excess of caustic soda to a solution of alum 
 or of sulphate of alumina. The mixture is kept at aboil until the precipitate 
 formed at first is entirely re-dissolved. Sulphate of soda, and, if common 
 alum was used, sulphate of potash, were always present. It is now sold in the 
 solid state, and containing very little foreign matter. As its name implies, it 
 is used by printers as a mordant for pinks. The calico, after treatment with 
 the aluminate, is passed through a solution of chloride of ammonium or 
 chloride of zinc, by the action of which alumina is deposited on the fibre. 
 
 Aluminate of soda is as yet little used among dyers. Though alkaline it is 
 capable of fixing colours upon wool, which cannot be blackened by the re- 
 action, as in case of the stannates and plumbates. Indeed, with judicious 
 management the aluminate of soda can be made to produce every effect 
 derivable from alum, and, in addition, certain; others, which the latter is 
 incapable of yielding. 
 
 Aluminate of potash is similar in its action to the soda salt, but being more 
 costly is rarely used. Mixed with oil it has been proposed as a mordant for 
 cotton to be dyed with madder. The shades obtained were fast but dull. 
 
MORDANTS. 
 
 535 
 
 A double chloride of aluminium and ammonium applied to cotton yields 
 with the woods a variety of browns, such as cinnamon and Esterhazy. It 
 would probably repay a closer investigation. 
 
 Iron Mordants. 
 Copperas (Green Vitriol, Protosulphate of Iron, or Ferrous Sulphate) is 
 generally manufactured from the soft whitish iron pyrites, or sulphuret of iron 
 found in the coal measures, and familiarly known as " brass lumps." When 
 exposed to air and moisture the latter is decomposed, hydrogen gas escaping, 
 and oxygen being absorbed, whence the sulphide of iron is converted into 
 sulphate of ferrous oxide. As the amount of sulphuric acid generated by the 
 oxidation of the sulphur is often more in quantity than the iron is able to 
 saturate, old iron of all kinds is added to the liquid, which drains from the 
 heaped-up beds of pyrites. Copperas forms semi-transparent crystals of a 
 pale greenish-blue, and contains 45 per cent of crystalline water, on the ex- 
 pulsion of which, by careful heating, a white powder remains, harsh to 
 the touch. The crystals of copperas dissolve in about ij parts of cold, 
 and in one-third its weight of boiling, water. At common temperatures 
 it oxidises and turns brown, being partially converted into ferric sulphate 
 (sulphate of the peroxide of iron). This change takes place the more readily 
 in proportion as the copperas and the air are damp, and as the crystals have 
 been formed from a neutral solution. Copperas should be chosen well 
 drained from the mother-liquor, forming bold, hard, clean crystals of a 
 decided green colour. If it is soft, dull, and of a whitish or greyish green, 
 known in the trade as " milky," the presence of alumina is to be suspected. 
 To ascertain this point a small portion is dissolved in water, and boiled with 
 pure nitric acid. To this liquid, whether clear or not, a large excess of pure 
 caustic soda, preferably that prepared from metallic sodium, is added. The 
 whole is digested in a clean, covered iron vessel, diluted with distilled water, 
 and filtered. If a white precipitate appears on adding to the clear filtrate a 
 solution of pure sal-ammoniac, the copperas contains alumina. Most com- 
 mercial samples will be found to contain this impurity to a trifling extent. If 
 the pyrites employed have been ill selected and are contaminated with alum- 
 shales, or if the copperas has been crystallised from a highly concentrated 
 solution, sulphate of alumina maybe present to a very serious extent, and may 
 render the copperas practically worthless. The presence of alumina must be 
 regarded rather as the result of mismanagement than of intentional fraud. 
 Zinc and copper are rarely present, and never, probably, in injurious doses. 
 The latter might be very readily detected by dissolving a little of the sample, 
 boiling with nitric acid, and adding to the liquid ammonia in excess. The 
 precipitate which subsides is then filtered off. If the clear filtered liquid shows 
 a blue tinge, copper is present. Lime is sometimes dusted over copperas to 
 give it a brownish appearance, for which some consumers have a preference. 
 The applications of copperas in dyeing and printing are less extensive 
 in the present day than was formerly the case. In producing logwood blacks 
 upon wool it has been largely replaced by the bichromate of potassa,at the cost, 
 it is true, of the stability of the resulting shade. For saddening olives, drabs, 
 clarets, &c, and for cotton blacks, it has been generally discarded in favour of 
 a nitrate of iron. Some dyers are very partial to an article sold as " calcined 
 
HHHHHHH 
 
 —WW 
 
 536 
 
 DYEING AND CALICO PRINTING. 
 
 copperas," the value of which is very doubtful. If the copperas has been 
 really calcined it is reduced to an insoluble powder, which will subside to the 
 bottom of the beck, and will have no more influence on the dyeing process 
 than an equal weight of sand. If the crystalline water has been merely 
 expelled by heat the salt will instantly return to the hydrated state on contact 
 with water. The solutions of the dry and of the crystalline salt must be 
 absolutely identical. 
 
 Persulphate of Iron (Ferric Sulphate, or Red Sulphate of Iron.) — This 
 salt contains iron in the state of peroxide (ferric oxide), instead of protoxide 
 as in copperas. It may be prepared by heating 30 lbs. of hydrated ferric oxide 
 of iron, 70 lbs. of red oxide of iron, and 150 lbs. of oil of vitriol. Or a solu- 
 tion of green vitriol is mixed with half as much sulphuric acid as it already 
 contains, and then heated with nitric, in small quantities, til! all the iron is 
 peroxidised. 
 
 Persulphate of iron is in the mass a yellowish body, and dissolves in water 
 with a pale yellow colour. In the anhydrous state it is a white powder. Per- 
 sulphate of iron is rarely manufactured and used in a state of purity, but it 
 forms a considerable part of many of the mordants sold under the name of 
 nitrate of iron. 
 
 Muriate of Iron (Solution of Protochloride of Iron, or Ferrous Chloride). 
 — This mordant is made by dissolving scrap iron in hydrochloric acid, keeping 
 the metal in excess. It very readily takes up oxygen, and suffers decom- 
 position if exposed to the air, whence it should be kept in well-stoppered 
 bottles. It generally is sold at about 8o° Tw. If concentrated it deposits 
 pale green crystals, which must be carefully kept from exposure to the air, 
 and which are sometimes preferred to the liquid. They are deliquescent, and 
 easily become peroxidised. Muriate of iron is not extensively used. It assists 
 in the production of certain catechu drabs and slates, and i9 sometimes 
 employed along with salts of manganese. 
 
 Permuriate of Iron (Solution of Perchloride, or Ferric Chloride) is made 
 by dissolving metallic iron in a mixture of nitric and hydrochloric acids. It is 
 very rarely used. 
 
 Black Liquor (Acetate of Iron, sometimes called also Black Mordant). — 
 The properties, preparation, and uses of this important mordant have been 
 incidentally described in speaking of madder (p. 290). 
 
 Nitrate of Iron. — This name is somewhat promiscuously applied to an 
 entire class of compounds which differ widely in their composition, their pre- 
 paration, and their uses. They may be divided into three classes, known as 
 "blue," "black," and "saddening" or "common," irons. The first- 
 mentioned are used for dyeing blues upon cotton or upon silk (the latter less 
 frequently since the introduction of the aniline blues) with the aid of prussiate 
 of potash (ferrocyanide of potassium). 
 
 Black irons serve for dyeing or printing blacks upon cotton, and to a less 
 extent upon animal fibres, along with myrobalans, divi-divi, galls, sumac, log- 
 wood, &c. Common or saddening irons are employed for " saddening " 
 drabs, browns, clarets, &c. 
 
 Some nitrates of iron are really what the name implies, compounds of 
 nitric acid with iron, the latter being, as a rule, entirely in the state of per- 
 oxide. Others are mixtures, in the most variable proportions, of the true 
 
MORDANTS. 
 
 537 
 
 nitrate and of the sulphate of iron, and in others acetic acid is present, as well 
 as the nitric and sulphuric. In specific gravity nitrates of iron range from 
 40 to 120 Tw. Some of the varieties are prepared from copperas, some from 
 scrap iron, and others from both. Previously made nitric acid is used in some 
 cases, whilst in others the iron is dissolved by nascent nitric acid, generated 
 by the action of sulphuric acid upon nitrate of soda. 
 
 Taking first the " blue " irons, used for dyeing Prussian blues upon silk or 
 cotton, we find that they are " sharper " than the " black " and " common " 
 irons. They contain, in other words, a relatively larger amount of acid and a 
 smaller of iron. If they are too " dead " — that is, if the proportion of iron 
 be too great — a large part of the colour formed will be deposited, not on the 
 fibre, but at the bottom of the dye-beck, and the part which is fixed upon the 
 goods will be uneven, flat, and loose. Still the blue nitrate of iron must not 
 be too raw, or the shades resulting will be meagre, and the fibre will be in 
 danger of being " tendered " by the free acid. 
 
 For dyeing cotton-yarns or unmixed cotton piece-goods, a blue iron made 
 from copperas, and brought as closely as possible to a perfect per-salt, will 
 give shades superior to a pure nitrate made by the action of aquafortis upon 
 scrap iron. The following formula will give satisfaction : — Put into a large 
 cask, capable of holding at least 130 gallons, 5 cwts. of dry, clean copperas. 
 Pour upon it 130 lbs. of double aquafortis (nitric acid, at 64°Tw.),and stir the 
 whole well together, so that every part of the copperas may come in contact 
 with the acid. During this operation care must be taken to avoid the suffo- 
 cating fumes which are given off in great quantities. On this account the 
 manufacture of nitrate of iron is best carried on in open sheds where the wind 
 may have free play, or under a hood, connected with a chimney having a 
 powerful draught. At night the mixture is thoroughly stirred up again. The 
 stirring should not be too violent. The operator should avoid hasty circular 
 movements, and try, instead, to turn over every portion of the copperas, 
 thrusting his pole to the very bottom, and working as if groping with the end 
 for some lost article. The stirring is repeated the second day, morning and 
 night, and on the morning of the third day ; the third night it will be finished. 
 The copperas, if the operation has been successful, will be found entirely con- 
 sumed, or perhaps a few pounds may remain at the bottom of the cask. It is 
 then let down with water to about 70 or 8o° Tw., well stirred up, allowed to 
 settle, and drawn off into carboys. If the ingredients are good, and the 
 process has been carefully conducted, the resulting liquid will be clear and 
 bright. It is, of course, a nitro-sulphate of the peroxide of iron. If any of 
 the copperas has not dissolved in the nitric acid, but has been merely taken 
 up by the water added for dilution, a small quantity of proto-salt of iron 
 (sulphate) will be present. This iron, if preserved from light and from 
 extremes of temperature, keeps well. Still, especially in summer, it is not 
 advisable to make more than a fortnight's consumption at once. 
 
 If mixed piece-goods with a cotton warp, such as coburgs, delaines, &c, 
 have to be dyed blue, and if the worsted has first been got up to the required 
 shade with one of the aniline blues, a blue nitrate of iron made from copperas 
 is not admissible, since it works to some extent upon the worsted as well as 
 upon the cotton, and injures the tone of the former. If a light or sky-blue is 
 intended, or if the blue is to serve as the basis of a green, the following 
 

 Be 
 
 H9BH 
 
 538 DYEING AND CALICO PRINTING. 
 
 receipt may be followed : — Let down ordinary double aquafortis to half-strength 
 (32 Tw.) with water. Add to this gradually scrap iron, which should be clean 
 and free from rust, so long as it is dissolved briskly with rise of orange fumes. 
 It will stand at 43 Tw. 
 
 If a deeper blue, of a rich " bloomy" tone, is required, either of the two 
 following receipts will serve the purpose : — 
 
 No. 1. Nitrate of soda, freed from chlorides 24 lbs. 
 
 Oil of vitriol 20 ,, 
 
 Water 15 gals. 
 
 Iron, scrap, as much as required. 
 Pour the water upon the nitrate of soda, and stir to promote solution. When 
 dissolved, add the acid and the iron by degrees, not letting the mixture get 
 too hot. 
 
 No. 2. Nitrate of soda 16 lbs. 
 
 Oil of vitriol 20 ,, 
 
 Cold water 13 gals. 
 
 Scrap iron as before. 
 Mix the ingredients as above stated, and keep up a steady action, taking care 
 not to let the heat get excessive. It is generally preferable not to add the 
 whole of the oil of vitriol at once. 
 
 Both these " blue irons " are unstable, and if kept many days are apt to 
 deposit a large amount of sediment. 
 
 In " black irons " perfect saturation of the acid is a matter of great 
 moment. In black-dyeing no substance is employed which, like the prussiate 
 of potash, is able to neutralise any excess of free acid, which, if present, 
 damages the colours, the goods, and, in case of printing, the colour-do&ors, 
 and even the copper cylinders. Still it is needful to avoid the opposite 
 extreme, for if the nitrate is overloaded, so that the oxide of iron is not 
 slowly and regularly delivered to the fibre, the goods will, when completed, 
 appear spotty and cloudy, or may even be smeared with buff patches, where 
 oxide of iron has been deposited too irregularly and rapidly to combine with 
 the tannin. For blacks, as a general rule, a nitrate of iron made from copperas 
 is preferable to one prepared from the metal. The receipt given above for a 
 blue iron for cotton skeins will serve very well for blacks, the nitric acid, for 
 the weight of copperas given, being reduced to 120 lbs. 
 
 For blacks, it is not necessary that the whole of the iron should be per- 
 oxide. Belter shades can, in fact, be produced with a nitrate of iron in which 
 a proportion of proto-salt is still present. The result of the process, as worked 
 with the above modification, is diluted with water to about 50 Tw., if for 
 dyeing, but to 80° if for printing. 
 
 Some makers add to black nitrate of iron a certain amount of brown sugar 
 of lead, which should not exceed 95 lbs. to 138 lbs. of the copperas originally 
 used. The result is that the oxide of lead combines with its equivalent of the 
 sulphuric acid present, and falls down as insoluble sulphate of lead, whilst the 
 acetic acid, formerly combined with the lead, seizes upon the oxide of iron in 
 its room. Should, however, any excess of nitric acid be present, this seizes 
 the iron in preference to the acetic acid, a portion of which remains free. As 
 free acetic acid is much less injurious to fibres and to colours than free nitric 
 
MORDANTS. 
 
 539 
 
 acid, such a nitrate of iron is less likely to prove dangerous. Hence nitrates, 
 with the mixture of acetate, are sometimes used as Burling Irons, for the fol- 
 lowing purpose : — In dyeing woollens a black, or indeed other shades, it is very 
 commonly found, when the goods leave the dye-beck, that they are sprinkled 
 over with small specks which have failed to take the colour, and have remained 
 white, or rather a dirty grey. These spots — technically called " burls " — are 
 caused by portions of cotton which have become intermixed with the wool, 
 and which, not having the same affinity for colours as the wool, escape undyed. 
 In case of black goods, if these spots are very numerous, the pieces are sub- 
 mitted to a formal cotton-dyeing process, with an astringent and with nitrate 
 of iron. In the selection of the latter much care is required. If too sharp it 
 alters or destroys the shade of the wool. If the iron is in excess the goods 
 will be disfigured with rusty stains. The above-mentioned black iron, with 
 the addition of acetate of lead, is preferred by many practical men for this 
 purpose. 
 
 The "common" or "saddening" irons are sharper than those used for 
 black dyeing, in order that the oxide of iron may be deposited very slowly, 
 and may combine more firmly with the tannin of the sumac, myrobalans, &c, 
 and may the better resist treatment with alum or tin mordants. They are, as 
 far as possible, perfedt per-salts of iron. 
 
 The following receipt is in extensive use : — Prepare a nitrate of iron by the 
 process given for " blue irons " on cotton-yarns. The weight of nitric acid 
 to 5 cwts. of copperas may be 130 to 135 lbs. After the iron has been worked 
 as above directed, the liquid is run off from any residue of undissolved 
 copperas, and then diluted with water. By this means no unconverted proto- 
 sulphate of iron is dissolved as such and mixed with the nitrate of iron. 
 
 Common Iron for Drabs. 
 
 Let down nitric acid (double aquafortis) to 34 Tw., and of it take 100 lbs. 
 Dissolve in it 4 lbs. of clean scrap iron. Then add by degrees as much 
 copperas as it will take up, which will be about 84 lbs. Let it down with water 
 to about 6o° Tw. 
 
 Muriatic acid should never be used in the manufacture of nitric acid. The 
 nitric acid employed should be free from this impurity, and if nitrate of soda 
 is used it should be freed from common salt by re-crystallisation. Muriatic 
 acid not only retains the iron more tenaciously than nitric, but delivers it upon 
 animal fibre. 
 
 In examining samples of nitrate of iron the following instructions may 
 prove useful : — Mix a portion with pure hydrochloric acid, and dilute with dis- 
 tilled water. If a white precipitate is formed on adding a solution of chloride 
 of barium, sulphuric acid is present. This shows either that the sample has 
 been made — wholly or in part — from copperas, or that sulphuric acid, as such, 
 has been added. Dilute another portion of the sample slightly with distilled 
 water, and add pure ammonia in excess. Filter off the precipitate, evaporate 
 the clear filtrate to dryness, and heat the residue to redness in a small porce- 
 lain capsule. If any fixed matter remains the sample has been got up with 
 nitrate of soda. Another portion is diluted with distilled water, a few drops 
 of pure nitric acid being added to prevent turbidity. A solution of nitrate of 
 silver is then added. If a white curdy precipitate is formed, either some 
 
■■■■I 
 
 BBBBBBHHHBBBHHH 
 
 540 
 
 DYEING AND CALICO PRINTING. 
 
 hydrochloric acid (muriatic acid) is present, or, if nitrate of soda has been 
 found, it may have been contaminated with common salt. 
 
 To detect alumina, a little of the sample is boiled with a mixture of nitric 
 and hydrochloric acids, to peroxidise any iron that may have remained in the 
 state of protoxide. Pure caustic soda (prepared from metallic sodium) is dis- 
 solved in a little water, and added to the sample thus treated in decided excess. 
 It is then boiled in a clean iron vessel, and filtered. To the clear filtrate a 
 solution of chloride of ammonium is added. If a white precipitate appears 
 alumina is present. 
 
 In order to determine whether any part of the iron present in a sample is in 
 the state of protoxide or not, a solution of carbonate of soda is slowly dropped 
 in. If the sample is a pure peroxide salt, all the iron present being brought 
 to the highest state of oxidation, the precipitate formed will be uniformly pale 
 yellow. If any protoxide be present a greenish or olive turbidity will appear 
 in the liquid. 
 
 It may sometimes be required to find the comparative acidity of two 
 samples of nitrate of iron. For this purpose bring both to the same specific 
 gravity, by adding water to the stronger, and noting the quantity required. 
 Equal measures of the two samples are then taken, and into each of them a 
 standard solution of carbonate of soda is run from a burette, stirring after 
 each drop, till the exact point is reached, when the liquid is neutral to litmus- 
 paper. The number of degrees consumed in each case gives the respective 
 acidity of the samples. 
 
 But in the most important points — namely, the purity, brightness, perma- 
 nence, and evenness of the shades produced — the only method to decide 
 on the quality of a sample of nitrate of iron is to dye with it on a small 
 scale. 
 
 In order to test " blue iron " equal measures of each sample are diluted 
 respectively with equal quantities — about five or six times their own bulk — of 
 cold distilled water. Equal weights of clean calico or of cotton-yarn are then 
 allowed to soak in each sample for an equal length of time. The swatches 
 are then taken out and allowed to drain. Meantime, equal measures of a 
 solution of prussiate of potash, diluted with equal quantities of water, are 
 placed in a number of glasses of suitable size, and in these the swatches are 
 respectively steeped for an equal length of time. They are then taken out, 
 rinsed in cold water, dried, and compared. 
 
 " Black irons " are tried by taking a number of equal swatches of clean 
 calico, and steeping the whole of them in a solution or decoction of snme 
 astringent — such as galls, myrobalans, sumac, &c. — for one hour. They are 
 taken out and allowed to drain, and are then placed respectively in the different 
 samples of nitrate of iron, two fluid drachms of each being diluted for this 
 purpose with half a pint of cold water. After soaking for ten minutes the 
 swatches are taken out, rinsed in cold water, dried, and compared. 
 
 For testing " common irons," swatches treated as above are steeped in a 
 weak solution of alum. That which is least affected by this treatment is 
 preferred. 
 
 The following iron mordant is recommended by some dyers as safe and 
 useful : — Dissolve 78 lbs. red oxide of iron in 117 lbs. sulphuric acid. Dilute 
 with water, and add 17 lbs. of sulphate of potash, and allow the compound to 
 
MORDANTS. 
 
 54* 
 
 crystallise. It gives results very similar to those produced by the nitrates of 
 iron made from copperas. 
 
 Alkaline Iron Mordants. 
 Certain compounds of iron are soluble in alkalies, and may be used as 
 mordants : — 
 
 1. Take a very neutral persulphate of iron, dissolve it in water, and precipi- 
 tate it with the phosphate of soda. The precipitate — a white powder — can be 
 dissolved in ammonia, and constitutes the mordant in question. According to 
 Persoz, a madder-bath, spent as far as the ordinary mordants are concerned, 
 will still dye goods mordanted with this preparation. 
 
 2. A concentrated solution, either of metallic iron or of copperas in nitric 
 acid, is mixed with a strong solution of carbonate of potash. The precipitate 
 which first forms re-dissolves in an excess of the alkaline liquid, forming a 
 red solution. 
 
 Lead Mordants. 
 
 Though several compounds of lead are used in dyeing and printing, this 
 metal can scarcely be said to give rise to true mordants. The acetate (sugar 
 of lead) and still more the sub-acetate (basic acetate) have a great affinity 
 for colouring matters, and when the latter is added to the solutions of dye- 
 wares everything dissolved is generally precipitated, and the supernatant 
 liquid left colourless. These lakes are, however, of little value, being void of 
 depth and brilliance. This arises from the fad that a great variety of other 
 substances besides the tin&orial principles are also precipitated. Hence the 
 lead-lakes are not articles of commerce, and are not employed in pigment 
 styles. The affinity of lead for vegetable fibres is not great, and the liability 
 of all colours of which it forms a constituent to become blackened, or at least 
 darkened, on exposure to sulphuretted hydrogen is a serious obstacle to its use. 
 It is not a good mordant for wool, where it is liable to injury from the presence 
 of sulphur. In 1859 Messrs. Perkin and Gray patented a process for fixing the 
 aniline purple or mauve by means of a lead mordant. In dyeing, the goods 
 are worked alternately in solution of acetate of lead and in ammonia, and 
 then dyed in the ordinary manner. In printing, acetate of lead is applied to 
 the cloth, and fixed by means of a mixture of soda crystals and ammonia. 
 The process is not now in common use. 
 
 Nitrate of Lead is formed by dissolving litharge in nitric acid with the 
 aid of heat, and allowing the solution to crystallise. It forms large white 
 crystals, readily soluble in water. It is used in mixing murexide purple, and, 
 like the acetate in forming chromate of lead in cotton goods, along with the 
 chromates of potash. 
 
 Sulphate of Lead, although insoluble in water, has the property of at- 
 taching itself to vegetable fibre, and can thus serve as a preparation for chrome 
 yellows and oranges. 
 
 Alkaline Solutions of Lead. 
 
 Lead is also capable of playing the part of an acid and combining with 
 
 alkalies. The plumbite of soda is formed by dissolving litharge in caustic 
 
 soda as long as anything is taken up. The resulting liquid must be preserved, 
 
 as far as possible, from contact with air. The plumbate of soda is formed in 
 
SB 
 
 
 HH 
 
 542 
 
 DYEING AND CALICO PRINTING. 
 
 a similar manner, red-lead being substituted for litharge. Both the plumbite 
 and the phimbate deposit a certain amount of lead upon vegetable fibres, and 
 can be used in getting up chrome-yellows. Their affinity for organic colouring 
 matters is too feeble to admit of them serving for purposes similar to the 
 stannates. 
 
 Tungsten Mordants. 
 
 Tungsten, or wolfram, is a metal which is frequently found along with tin, 
 and which has been tried as a mordant in various states of combination. The 
 use of certain tungstic salts in dyeing was patented, in 1847, by Robert 
 Oxland. He directs a chloride of tungsten to be made by boiling tungstate of 
 soda with nitro-hydrochloric acid, and to be used in cloth-dyeing in place of 
 the salts of tin. The shades produced upon wool with logwood are violet, 
 passing on prolonged boiling into claret, and finally into black. He prepares 
 the tungstate of soda by roasting the ore, either native wolfram (the double 
 tungstate of iron and manganese)or " native tungstic acid," with soda-ash, 
 or sulphate of soda. As prepared under this patent, the tungstate of soda 
 would require to be freed from admixtures of ferrate and manganate. 
 
 Haeffely, in a patent dated 1854, claims the use of this tungstate of soda 
 either as a substitute for, or as an addition to, the stannate of soda. 
 
 The general conclusion, among printers who have given the tungstate a fair 
 trial, is unfavourable. 
 
 Antimony Mordants. 
 
 Antimony, like bismuth, has a considerable analogy with tin. When acted 
 upon by strong nitric acid it — like tin — forms an insoluble oxide, and its acid 
 solutions, like those of bismuth and tin, are rendered turbid and precipitated 
 if largely diluted with water, — a reaction which may be prevented by the 
 addition of tartaric acid. 
 
 The tartrate of antimony, the double tartrate of antimony and potassa, — 
 commonly known as tartar emetic, — the chloride and the double oxalate of 
 antimony and potassa, and the alkaline antimoniates, have been made the sub- 
 jects of various experiments in dyeing and printing. The results, though they 
 do not preclude all hope of success in the future, have not been satisfactory. 
 
 Solutions of antimony along with oxalic acid have been tried for cochineal- 
 scarlets in place of the corresponding tin preparations. The result was a coarse 
 harsh shade, without the richness and softness of the tin cochineal-scarlet. As 
 41 prepares " for steam-colours, all the antimonial compounds hitherto tried 
 have shown themselves inferior to tin. 
 
 Jones Martyn Roberts, in 1853, patented the use of antimony, " rendered 
 soluble in any form," as a mordant. He also claims its use as a " brightener." 
 It is remarkable that several antimonial compounds, if digested in very small 
 quantity with logwood liquor, modify its colour to a rich rose-purple, almost 
 approaching certain aniline colours. The logwood so modified gives, how- 
 ever, only weak stains upon fibres and tissues. 
 
 Antimonial compounds have been used in the preparation of aniline colours, 
 and the double tartrate (tartar emetic) serves as a mordant for fixing colours 
 of this class upon cotton. 
 
 Solutions of antimony yield readily, with solutions and decoctions of dye- 
 wares, a series of lakes, many of which, if the antimony is free from iron, are 
 
MORDANTS. 
 
 543 
 
 eminently beautiful. This property of antimony, which was then no novelty, 
 was claimed by F. A. Gatty, in a patent obtained in 1856. He applies the salts of 
 antimony, preferably the chloride, for the purpose of precipitating the colouring 
 matters of dye-materials, such as sapan wood, logwood, cochineal, quercitron, 
 &c, thereby producing colours called lakes, for the manufacture of which other 
 metallic salts have hitherto been used. To 1 gallon of chloride of antimony, 
 of 8o° Tw., he adds 20 gallons of well-aged sapan or Lima-wood liquor, at 
 7 Tw. ; the whole is then well stirred and left to stand for a few hours, and 
 then is put on a filter. When the liquor has run off he adds 4 gallons of 
 water to wash the precipitate. The washing is repeated a second time. 
 When the water is drained off the lake is finished, and may either be dried or 
 used in the wet state. The shade of the lake may be varied from a crimson 
 to more of a scarlet, by using more or less of the chloride. For " purple or 
 violet lakes " logwood is substituted for the sapan wood, and bark-liqucr for 
 yellows. 
 
 The practical difficulty in this process is that the chloride of antimony is 
 precipitated by water alone as decidedly as by solutions of colouring matters. 
 Hence it follows that, in addition to the true antimonial lake, a variable quan- 
 tity of antimonic oxychloride (salt of algaroth) is thrown down, which dilutes 
 and " flattens " the colour of the lake. To prevent this an addition of tar- 
 taric acid would be necessary, previous to mixing the antimony solution with 
 the sapan liquor. 
 
 Bismuth Mordants. 
 
 Bismuth presents certain analogies with tin, which have led to the opinion 
 that it might be valuable as a mordant. It possesses a strong affinity for 
 colouring matters, and with proper precautions it gives rise to a variety of 
 beautiful lakes. On the other hand, its affinity for animal and vegetable fibres 
 is less decided than that of tin. Its acid solutions, on dilution with water, 
 are decomposed too readily, the bulk of the bismuth being thrown down, in 
 the state of an insoluble sub-salt, without the application of heat, and without 
 the presence of any organic fibre or tissue. This evil can be to some extent 
 prevented by the addition of acetic acid, but the shades produced, as far as 
 our present experience goes, though rich and brilliant, are deficient in evenness 
 and solidity. 
 
 In 1855 E. Kopp took out an English patent for the use of the aceto-nitrate 
 of bismuth as a " mordant for garancin colours." This salt was to be pre- 
 pared by dissolving as much bismuth as possible in hot nitric acid (strength 
 and temperature not stated), diluted with half its weight of water. On 
 cooling, yellowish crystals are deposited, which, dissolved in acetic acid at 
 8° Tw., constitute the improved mordant. According to the inventor, this 
 aceto-nitrate of bismuth gives, with garancin, peculiar bright crimsons, and, 
 when mixed with a solution of arseniate of iron in nitric acid, it produces, 
 with the same dye-ware, peculiar dark crimson and purple-crimson shades. 
 Prior to this date all the easily-prepared preparations of bismuth had been 
 tried in England, by C. O'Neill and others, without any valuable results. The 
 specification above quoted, after careful and repeated trials, yielded nothing 
 of any commercial value. Mr. O'Neill, who had an opportunity of examining 
 the patentees' original patterns, pronounces them no better than those obtained 
 in this country. 
 

 544 
 
 DYEING AND CALICO PRINTING. 
 
 Bismuth has two additional disadvantages as compared with tin : its price 
 is very considerably higher, and it is more liable to be blackened by sulphuretted 
 hydrogen in the atmosphere. 
 
 Chromium Mordants. 
 A variety of chromium compounds have a very decided adtion both upon 
 organic fibres and upon colouring matters. The most important of these is 
 chromic acid, which is always used in combination with potash. The bi- 
 chromate of potassa, commonly known as bichrome or red chrome, is a salt 
 too generally known to require any description. Pew commercial chemicals 
 are more generally met with in a state of purity, and it is, we believe, never 
 intentionally sophisticated. It should show no whitish or yellowish spots 
 or incrustations. It should be perfectly soluble in pure water, leaving no 
 sediment or turbidity. If a little nitric acid is added to the aqueous solu- 
 tion of bichrome, a solution of nitrate of baryta should not occasion any pre- 
 cipitate. If one appears, sulphuric acid is present, in the state of sulphate of 
 potassa. 
 
 The neutral or yellow chromate of potash is comparatively little used. Its 
 action is milder, and more easily regulated than that of the red chromate, and 
 with organic colouring matters it yields a variety of interesting results, many 
 of which require and deserve further investigation. Against the above-men- 
 tioned advantage must be set the fad that it is exceedingly variable in 
 composition, two samples being rarely found quite identical. The results are 
 hence uncertain. Those who wish to experiment upon its action on a practical 
 scale can employ a solution of 151 parts of bichrome and 143 parts of clean 
 crystallised carbonate of soda, not effloresced. 
 
 The principal use of red chrome is to produce blacks upon wool, along with 
 logwood, smaller quantities of other wares being added to modify the shade. 
 Chrome-blacks are cheap, both from the low price of the materials and from 
 the small amount of time and labour required. The shades produced are, 
 however, inferior both in beauty and permanence to the old logwood and 
 copperas black. 
 
 With other dye-wares red chrome produces a variety of browns, yellow- 
 browns, yellows, oranges, bottle-greens, olives, black-greens, and purples. 
 The action of the chromes upon logwood is exhaustively treated in Dr. Runge's 
 work, " Farben-Chemie," Part III. 
 
 Chromic oxide, in combination with acids, is also a mordant, though little 
 used. The most important of its compounds are the sulphate and the nitrate. 
 It has the disadvantage of imparting, in itself, a pale greenish colour, which 
 to certain shades would of course be fatal. Its affinity, for many colours at 
 least, is but feeble, and many dyers complain that the shades produced are 
 harsh and dull. 
 
 Chrome-alum, a double sulphate of chromic oxide and of potash, is occa- 
 sionally employed on the Continent. The salts of chromic oxide may be used 
 to fix aniline blues upon cotton. 
 
 From the immense use of bichrome in dyeing it is very possible that certain 
 quantities of this powerful poison may find their way into rivers. In all 
 sanitary legislation its exclusion, even in minute traces, should be rigorously 
 insisted on. 
 
MORDANTS. 
 
 545 
 
 Manganese Mordants. 
 
 Manganese has a very powerful affinity for organic fibre, both animal and 
 vegetable. This is most strikingly shown with the solutions of permanganate 
 of potash. If a slip of calico is plunged into such a liquid it rapidly takes a 
 deep brown colour, permanent as far as light is concerned, but not capable of 
 resisting treatment with acids. The intensity of the colour thus produced would 
 disqualify it as a mordant, except for some of the darkest shades. As the 
 compound of manganese thus fixed upon the fibre is a hydrated peroxide, and 
 as the protoxide is white, or exhibits at most a faint pinkish tinge, it may be 
 used as a mordant by bringing a powerful deoxidising agent to act upon it either 
 along with or immediately before the colouring matter. 
 
 The use of the sulphate and chloride of manganese in producing certain 
 so-called bronze effects upon cotton, independent of any organic colouring 
 matter, is not a case of mordant action, and is, moreover, nearly obsolete. 
 
 Zinc Mordants. 
 
 The affinity of oxide of zinc for organic fibres is very feeble. With the 
 majority of colouring matters, also, it shows little disposition to form lakes. 
 Hence its uses as a mordant are unimportant. Some experimentalists have 
 obtained a scarlet from sandal wood with a mordant of chloride of zinc. 
 With murexide salts of zinc produce a yellow, which, though good, has no 
 distinctive feature to recommend it in preference to similar shades more 
 cheaply producible. Chloride of zinc, on account of its deliquescent nature, 
 is sometimes added to printers' colours with the object of preventing the 
 mixture from drying up. It is also employed to fix the alumina of " alkaline 
 pink mordant" upon the fibre. Certain manufacturers of mordants maintain 
 that if a solution of zinc — nitrate, chloride, or sulphate as the case may be — 
 is added to a tin spirit, it causes the tin to be thrown better upon the fibre, 
 and by being thus more thoroughly utilised it enables a smaller quantity to 
 answer the same purpose. We know of no facts to substantiate this 
 hypothesis, which we are inclined to suspect may have been devised to justify 
 what was at one time a not uncommon mode of adulterating the preparations 
 of tin, and is probably not yet extinct. The action of chloride of zinc upon 
 alkaline pink mordant, as above mentioned, depends obviously upon a principle 
 which cannot apply here. 
 
 Arsenic Mordants. 
 
 Arsenious acid occurs in a great number of printing receipts, its funclion 
 being often very doubtful. In some cases it plays the part of an alterant 
 rather than of a true mordant. Arsenite of soda mixed with the acetate of 
 alumina is employed as a mordant for printing aniline colours upon cotton. 
 Arsenious acid, boiled with decoctions of the woods, fixes a variety of browns 
 upon cotton and woollens, which are, however, more curious than practically 
 important. The poisonous nature of the arsenical compounds undoubtedly 
 tends to restrict their tinctorial applications. 
 
 Copper Mordants. 
 Certain preparations of copper are rather extensively used in dyeing and 
 printing, although their function is less that of mordants, strictly so-called, 
 than of alterants, or oxidising agents. 
 
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 P Hi 
 
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 BBB 
 
 546 
 
 DYEING AND CALICO PRINTING. 
 
 Acetate of copper, commonly known as verdigris, occurs in commerce in 
 several varieties. The common blue verdigris is a bibasic salt, forming 
 delicate, loose, blue scales and needles, which yield a blue powder. It con- 
 sists of 2(CuO,C 4 H 3 Cu0 4 ). It is prepared by packing wine-lees loosely in 
 casks, with straw, till the acetous fermentation sets in. When that is ended 
 they are arranged in pots covered with straw in alternate layers, with alternate 
 layers of copper plates heated to the temperature of 40 C. These plates 
 when used for the first time are previously moistened with a solution of the 
 neutral acetate of copper and dried. At the end of about three weeks the 
 plates are withdrawn, set upright to dry, dipped six or eight times in water in 
 the course of as many weeks, and again left to dry, during which operation 
 the verdigris continually swells up. It is then scraped off, and the plates are 
 again replaced alternately with fresh acid wine-iees, and the same operations 
 are repeated till the copper is corroded away. 
 
 Common green verdigris is a mixture of the sesqui-basic acetate of copper, 
 with small but variable quantities of the bibasic and terbasic salts. It is pre- 
 pared by repeatedly sprinkling copper plates with vinegar in a warm room. 
 
 In calico printing acetate of copper is used in solution, and is prepared by the 
 double decomposition of sulphate of copper and sugar of lead. The following 
 mixture is often employed : — 1 gallon of water at 160 F. ; 4 lbs. white sugar 
 of lead ; 4 lbs. sulphate of copper. The ingredients are previously ground 
 up, and the mixture is frequently stirred till the decomposition is complete, 
 when the sulphate of lead is allowed to deposit, and the clear liquid is drawn 
 off. The respective proportions of sulphate of copper and of sugar of lead 
 are varied in different establishments, some using 2 lbs. only, and others as 
 much as 6 lbs. of sugar of lead to 4 lbs. of sulphate of copper. It is obvious 
 that where the smaller proportions of sugar of lead are used, the resulting 
 solution must contain a considerable quantity of sulphate of copper mixed 
 with the acetate. 
 
 The uses of verdigris are less extensive than was formerly the case. It is 
 used in many catechu colours, in certain resists for indigo blues, and as an 
 oxidising agent in a few steam colours. In black dyes for silks and for hats, 
 and for printing blacks on silk goods, verdigris is also employed. Logwood 
 blues on wool are also dyed with an admixture of a salt of copper, generally 
 verdigris. The Act George III., 20, which imposes a penalty of ,£20 for every 
 piece of cloth dyed blue by means of this process, is a curious specimen of the 
 commercial legislation of our forefathers, and is supposed to be still unrepealed. 
 Verdigris figures in a great variety of old dyeing receipts where its utility is 
 exceedingly doubtful, or rather where its inutility has been satisfactorily 
 demonstrated. 
 
 Ammoniuret of Copper. — On adding ammonia to solutions of the sul- 
 phate, nitrate, or other salts of copper, a pale bluish-green precipitate is thrown 
 down, which, on the addition of a larger quantity of ammonia, re-dissolves, 
 forming a solution of an intense violet-blue. Cotton, steeped in this solution, 
 swells up, becomes a jelly, and is finally liquefied. On the addition of an 
 acid, however, the cotton is re-precipitated as a white powder, chemically 
 unaltered, but having its fibrous structure destroyed. Dilute solutions of the 
 ammoniacal copper compound may be used for dyeing a pale green, by padding, 
 drying, and finally washing. 
 
MORDANTS. 
 
 547 
 
 Chloride or Muriate of Copper. — This compound is best made by the 
 double decomposition of a mixture of chloride of calcium and sulphate of 
 copper in hot water, the whole, after the solution of the ingredients and after 
 thorough stirring, being left to settle, and the clear liquid drawn off for use. 
 It is much used on the Continent, but in English dye- and print-works it is 
 generally replaced by the sulphate, or the nitrate used along with sal-ammoniac. 
 
 Nitrate of Copper. — This salt is sold both in the form of crystals and in 
 solution. It may be easily prepared either by dissolving copper clippings and 
 turnings in nitric acid to decided saturation, or else by a process of double 
 decomposition. For this purpose a saturated solution of sulphate of copper 
 is mixed with a solution of the nitrate of lime, or, better, the nitrate of lead, 
 in equivalent quantities. The solution thus obtained is perfectly neutral, and 
 may be concentrated to any strength required. The nitrate of copper, 
 whether in the crystal or in solution, is of a deeper and less green shade than 
 the sulphate. It is less generally met with in the solid state, as it is very 
 deliquescent, and attracts moisture from the atmosphere. In solution it is 
 generally sold at from 8o° to 100° Tw. Those who judge of its quality 
 merely by means of the hydrometer often find themselves mistaken, as it is 
 not unfrequently contaminated with zinc and other bodies. The presence of 
 such foreign matters will be easily understood if we remember that nitrate of 
 copper is now generally made, not by the dyers or printers themselves, nor 
 by manufacturing chemists whose speciality it is to prepare tinctorial 
 requisites, but by workers in metals. These parties use nitric acid to a con- 
 siderable extent in cleansing articles of copper and its alloys, &c. The 
 resultant liquids, mixed promiscuously and concentrated, are sold at a very 
 cheap rate. Such samples of nitrate of copper, beside containing foreign 
 metals, may be too acid, and may then prove very injurious. The comparative 
 acidity of different samples may be judged by noting the relative amounts of 
 caustic soda solution of uniform strength which are required to produce a 
 permanent precipitate, i.e., one which will not disappear on agitation. If an 
 excess of ammonia is added to the nitrate of copper, the precipitate formed 
 at first should entirely re-dissolve. If anything remains undissolved, iron or 
 lead is probably present. If a portion of the nitrate of copper is mixed with 
 a little pure hydrochloric acid, and a current of sulphuretted hydrogen passed 
 through it until it is completely saturated, the precipitate produced should 
 contain the whole of the fixed matter present. If it, therefore, be filtered off, 
 the clear filtrate, on evaporation to dryness and raising to very low redness, 
 should leave nothing. Any permanent residue is probably due to the presence 
 of zinc, a frequent, though for the most part an unintentional, impurity. 
 
 Sulphate of Copper, known also as Blue Stone, Blue Vitriol, and Roman 
 Vitriol, is now generally prepared on the large scale direct from the ores. It 
 forms large, hard, deep blue crystals, soluble in 3 parts of cold and in £ part 
 of boiling water. In a dry atmosphere the crystals are apt to efiloresce, losing 
 part of the 36 per cent of water normally present. A solution of blue vitriol 
 saturated at 62 F. stands at 36° Tw. If the crystals are exposed for some 
 little time to a temperature slightly exceeding that of boiling water, the water 
 of crystallisation is expelled, and there remains the anhydrous sulphate in the 
 form of a white powder. In contact with minute traces of water this powder 
 resumes its blue colour, and may, therefore, serve to detect the presence of 
 
 2N2 
 

 ' MM 
 
 548 
 
 DYEING AND CALICO PRINTING. 
 
 water in alcohol, etler, &c. At full redness the sulphate of copper is decom- 
 posed, the oxide of copper remaining in the form of a black powder. 
 
 Sulphate of copper is often found to be impure. The protosulphate of iron 
 (copperas) is capable of crystallising along with blue vitriol, in a very consi- 
 derable proportion, without any alteration in its form and colour. To detect 
 the presence of iron the solution is boiled with a little nitric acid, and an 
 excess of ammonia is then added. If any iron is present, brown flocks will 
 remain floating in the ammoniacal solution of copper. Zinc may be detected, 
 along with manganese, magnesia, &c, by the process with sulphuretted 
 hydrogen, as described under Nitrate of Copper. The sulphate of copper is 
 used in resists for indigo-blues. 
 
 Copper salts have, within the last few years, met with a new application in 
 dyeing and printing aniline blacks, the sulphide being preferred by many. 
 
 The presence of copper, where not specially required, should be carefully 
 avoided, as its action is generally injurious, and even in minute traces it is 
 capable of modifying shades in an unexpected and puzzling manner. With 
 madder it proves completely fatal, even in very small quantities. A piece of 
 sulphate of copper put into an indigo-vat throws it out of order, by 
 oxidising the white indigo and sending it — in an insoluble state — to the 
 bottom. This is a method of " rattening," not unknown in dye-works. 
 
 Tartar and Argols. 
 
 These substances, though not mordants, require a brief notice in addition to 
 the remarks made on p. 112. They occur in commerce in three principal 
 states, — white argol, red argol, and tartar. Good white argol is met with in 
 flattish pieces, having on one side a distinctly crystalline texture, and on the 
 other showing traces of the fibre of the wooden vessel in which it has been 
 allowed to crystallise. If a piece is broken the fracture should look bright and 
 crystalline, and the bits, if shaken together in the hand, should ring like 
 fragments of pots. Argol should melt slowly in the mouth with a pleasantly 
 acid, but not vinous taste. The powder should be white, faintly bordering 
 upon pink or pinkish-grey. On the addition of dilute nitric acid no effer- 
 vescence should be perceptible. An escape of gas shows the presence of 
 carbonates, either of lime or of the alkalies. If a weighed portion of the 
 sample is digested in dilute nitric acid, until everything soluble has been taken 
 up, sand and organic matter will remain, and may be filtered off. When 
 washed, dried, and weighed, it should not exceed 2 per cent, though in adulte- 
 rated samples it may reach 15 or 16. The dregs of white wines are now a 
 common sophistication. On drying they form small grey or reddish lumps, or 
 clots, less brittle than argol, and without a trace of crystalline structure. 
 This matter differs also in taste from argol, being very faintly acid. 
 
 The solution filtered from the organic matter and sand may be examined 
 for other impurities. If the addition of a solution of chloride of barium 
 produces a white turbidity or precipitate, sulphuric acid is present, showing 
 the probable existence of an alkaline sulphate (sulphate of soda) or of alum 
 as a sophistication. It must, however, be remarked that the juice of the 
 grape contains a certain small amount of sulphate of potash. If the precipi- 
 tate given by chloride of barium, however, is abundant, the sample cannot be 
 genuine. 
 
TARTAR AND ARGOLS. 549 
 
 Another portion of the solution may be mixed with a solution of nitrate of 
 silver. A white curdy precipitate indicates the presence of a chloride, pro- 
 bably common salt. 
 
 A third portion of the nitric acid solution of the sample is mixed with am- 
 monia, and oxalate of ammonia is added. If, on stirring the mixture and 
 allowing it to stand for a few minutes, a white precipitate is produced, lime is 
 present. A small amount of lime is of course naturally present, due to tar- 
 trate of lime. If the precipitate produced is plentiful, sulphate or carbonate 
 of lime has been added. 
 
 Red argols are less frequently sophisticated. Both these compounds are 
 extensively used in dyeing; the white kind for scarlets, crimsons, and other 
 grain-colours ; red argol is used for certain blacks and other dark shades. 
 
 White argol, dissolved, filtered, and re-crystallised, is known as grey tartar, 
 and on still further purification it becomes white tartar. The tartars are used 
 in dyeing pinks, maizes, &c. 
 
 Liquid tartar, otherwise known as protartar spirits, is prepared as follows : — 
 
 Mix — Grey tartar or white argol 10 lbs. 
 
 Sulphate of soda, crystals 10 „ 
 
 Dilute sulphuric acid, at go Tw 6 quarts. 
 
 Then add water sufficient to let down the whole to 17 Tw. This liquid is 
 employed by some dyers for " levelling " certain colours, especially aniline 
 blues, upon woollen and worsted goods. 
 
 Tartaric Acid, obtained by the decomposition of the tartrates, is exten- 
 sively used both in dyeing and printing. Sometimes it is sophisticated with 
 bisulphate of potash. To detect this fraud a small quantity of the sample is 
 heated to redness upon a slip of platinum foil, or in a small platinum capsule. 
 If bisulphate of potash is present a white fused mass will remain, but if the 
 sample is genuine nothing will be left. Tartaric acid is sometimes used in 
 grain-dyeing. In printing it serves for a discharge on Turkey reds and dip 
 blues, and in steam greens and blues it is used to decompose the yellow 
 prussiate of potash. 
 
 A solution of tartaric acid in water is sometimes sold under the curious 
 name of " essence of tartar." Not unfrequently this " essence " is weighted 
 with sulphuric acid, which maybe detected by acidifying with pure hydrochloric 
 acid, and adding chloride of barium in solution. A white precipitate shows 
 the presence of sulphuric acid, added either as such or as a sulphate. 
 
 Since the grape-disease first made its appearance, and since the accom- 
 panying rise in the price of argols, tartars, and tartaric acid, a number of 
 compounds have appeared in the market under such names as tartar substi- 
 tutes, pro-argols, pro-tartars, &c. These bodies profess either to economise 
 or totally to replace the real substances. Some of these contain argol or 
 tartar in various proportions ; others are mere mixtures of common salt, 
 oxalic, acetic, and sulphuric acids, alum, &c. These substitutes may in some 
 cases prove satisfactory. Certain dyers, for instance, are in the habit of using 
 argol, where nearly any acid would answer the end required. In such instances 
 the substitutes may give satisfaction. But where the distinctive properties of 
 the bitartrate of potash are really needed, these pro-argols can only lead to 
 disappointment. Some makers, however, prudently recommend that a certain 
 
'■£•&£ 
 
 SB 
 
 HB 
 
 S5 o DYEING AND CALICO PRINTING. 
 
 amount of genuine argol or tartar should be used along with the substitute. 
 One of these compounds, the so-called " tartar cake,'''' is made by mixing 
 sulphate of soda with seme free sulphuric acid and a small quantity of white 
 argol or tartar. The mixture is melted, run into thin layers, and broken up 
 when cold. It is deliquescent, corrosive, and intensely sour. In stuff-dyeing 
 it is used for the so-called sour browns. 
 
 Super-Afgol is white argol to which sulphuric acid has been added, 
 enough to combine with all the potash present. It is, therefore, a mixture of 
 sulphate of potash and of free tartaric acid. 
 
 The following is a mixture, patented by B. Barcroft, as a substitute for tar- 
 taric acid " in the production of blues and in the reduction of pinks in dyeing 
 and printing :" — Mix 14 quarts of sulphuric acid, at 170 Tw., with 12 quarts 
 of cold water, and allow it to stand tili cool. The inventor then " takes a 
 large vessel and places it in a water-bath, and pours into it 20 quarts of 
 boiling water, and adds 48 lbs. sal-ammoniac and 6 lbs. of white arsenic," 
 boiling till all is dissolved. The solution is then cooled down to 70° F. The 
 first mixture (dilute sulphuric acid) is then added, and the whole allowed to 
 stand till quite cold : 3 quarts of oxymuriate of tin, of 120° Tw., are then 
 added, and in a few days it will be ready for use. 
 
 A. E. L. Bellford attempts to prepare, from the reaction of sugar and nitric 
 acid, a body less highly oxidised than oxalic acid. Gatty patented the use of 
 lactic acid as a substitute for tartaric. These preparations, however, have 
 never come into general use, and are probably now completely abandoned. 
 
 Royal Blue Spirits. 
 Under this name is known a mixture of acids, used in dyeing Prussian blues 
 upon wool, for the purpose of decomposing the prussiate of potash. It con- 
 tains neither tin nor any other base. Where the yellow prussiate is employed 
 the following mixture is given as one in actual use : — 
 
 Sulphuric acid, at 90 Tw. 1 gallon 
 
 Spirits of salts, at 32 Tw 2 quarts 
 
 Double aquafortis, at 64 Tw 1 quart. 
 
 Some dyers prefer to diminish the latter ingredient by one-half. The whole 
 of the acids are well mixed together, carefully avoiding the fumes. 
 
 If the red prussiate of potash is used, the nitric acid (aquafortis) is omitted 
 altogether. 
 

BBS 
 
 ■BKlBB^ff MMBMBMBMMWMMWBB^MMMMWMB 
 
 Plal ■ VI. 
 
 " Gas-process " for Engraving Blocks for Printing. 
 
 The graving-tool is heated to redness by means of a small gas-burner, and destroys all parts 
 of the surface except those to be left in relief. 
 
 Designs Produced by the "Gas-process." 
 
(550 
 
 CHAPTER VIII. 
 
 PRINTING. 
 
 "DEFORE proceeding to give a systematic description of the various styles 
 
 £3 
 
 of printing, a brief account will be required of the two principal 
 
 machines used in modern print-works, — the perrotine and the cylinder machine. 
 The former of these executes a style of work very similar to hand-block 
 printing. Three wooden blocks, from 2 J to 3 feet in length, according to the 
 width of the pieces, and varying in breadth from 2 to 5 inches, have the 
 pattern engraved in relief on their surface. They are fixed, with their faces at 
 right angles to each other, in a stout iron frame, and can each in turn be 
 brought down upon the front, top, and back, of a four-sided iron prism, faced 
 with cloth, and revolving upon an axis. The goods to be printed pass between 
 the prism and the pattern-blocks, and receive the impressions in succession. 
 The blocks are forced down upon the calico by means of springs, so as to 
 imitate the pressure of the hand of the block-printer. After each impression 
 the block takes up a fresh coat of colour, by contact with a surface of flannel, 
 upon which the mixture is kept continually applied by means of a self-acting 
 brush. The perrotine is shown in section in Fig. 24, and in elevation in 
 Fig. 25, both these illustrations being taken from the " Traite de 1'Impression 
 des Tissus " of Persoz. 
 
 A, cast-iron frame, bbb, cast-iron tables, planed smooth, over which pass 
 the blanket, the back-cloth, and the calico to be printed, c c c, sliding pieces, 
 on which are screwed the block-holders, 3, causing the pattern-blocks, 2, to 
 move in turn against the layer of flannel and the pieces to be printed, by 
 means of the play of the levers 4 and 5, whose supports, 6, rest upon A, and 
 act, by means of coupling-rods, upon the beams, 7, keyed to the slides c. The 
 lower of these sliding-pieces is vertical, and takes by its own weight a retro- 
 grade movement, regulated by a counter-weight, eee are movable colour- 
 sieves, fixed to coupling-rods, and receiving a suitable movement from the 
 power which works the machine. The sieves are flat, and covered with cloth 
 on the face opposite to the block. They work in grooves on the sides of the 
 tables, and receive from the furnishing rollers the colours, which they then 
 pass on to the pattern-blocks, fff are colour-troughs, filled with the colour 
 mixture, and fitted each with two rollers, 8 and 10. The latter dips into the 
 trough, takes up colour, and transfers it to 8, which is -covered with woollen 
 cloth, and which it carries on to the sieves, e, where it is spread by the 
 brushes, 9. In order to regulate the amount of colour supplied to the sieves, 
 and thence to the blocks, the rollers, 10, are fitted with levers, 11, which, by 
 
■■■■ 
 
 ■ 
 
 
 552 
 
 DYEING AND CALICO PRINTING. 
 
 means of set-screws, bring them into more or less close contact with the other 
 rollers, 8. Thus the amount of colour taken up can be varied at will. The 
 revolution of the blanket, back-cloth, and pieces is reguiated by the following 
 contrivance : — At the angles of the three tables B are rollers, 1, their surfaces 
 being fitted with needle-points. These prevent the cloth from slipping as it 
 passes round, and cause the pieces to be printed to move on regularly. This 
 movement is effecled by the cog-wheels, 21 (Fig. 25), keyed on the ends of the 
 axles of these rollers, g is a roller which stretches the endless web, resting 
 with the ends of its axles on two cushions forming the ends of the screws, 12. 
 By these the roller, if needful, can be pushed further out, so as to stretch the 
 cloth to the degree required. H is another stretching-roller, which supports 
 the blanket and back-cloth, k is another roller, which serves to stretch the 
 
 Fio. 24. 
 
 blanket, back-cloth, and pieces. T is the blanket, passing round the semi- 
 circumference of the roller g, over h and behind k, round 1, and over the 
 surface of the tables B. Lisa cylinder from which the back-cloth is unwound, 
 having been first stretched by H, and smoothed by the scrimping-bars, 13. It 
 then joins the blanket at the roller k. m is a roller from which the piece to 
 be printed is uncoiled by the revolution of the machine, passing over the 
 scrimping-bars, 14, and joining the blanket and back-cloth at the roller K. It 
 accompanies the two latter till it arrives at g, when it is led off towards N, 
 and is dried on the hanging-rollers. The whole machine is moved either by 
 hand, with a winch, or by steam-power,'when a driving band is passed over 
 the pulley 18, arranged with different diameters, so as to give different degrees 
 of speed. It carries catches, locking into a sliding catch-box on the shaft 
 
PRINTING. 
 
 553 
 
 when the machine is set in motion. The movement of the machine is neces- 
 sarily intermittent, and is regulated so that the piece moves on a space exactly 
 equal to the breadth of the block, and moves forward while the sieves are 
 supplied with colour from the rollers, 8, 8. This arrangement is produced by 
 means of a dividing-wheel, 20. The wheels 21, keyed on the axle of the 
 cylinder 1, and having each the same number of teeth, are moved by a central 
 wheel with teeth in the same manner, and fixed behind the wheel 20. The 
 latter receives an alternating movement from a rack, 24, fixed in a copper 
 piece, 25. This rises and falls alternately, and is keyed at its lower end to 
 one of the spokes of the wheel 28. By altering the point of attachment to 
 the spoke the range of its movement is varied, more or fewer of the teeth of 
 the wheel are allowed to pass, and the advance of the piece at each movement 
 
 Fiq. 25. 
 
 is proportionately increased or lessened. It is further regulated by the ratchet- 
 wheel, d. At each half-revolution the lever 22 raises the catch, and throws 
 the wheels 21 out of gear during the next half turn; but as in working 
 these wheels there would necessarily be a backward movement, this is pre- 
 vented by a break, which consists of a pulley fixed on the shaft of the axle of 
 the wheel 20, and a wire, which, after making a turn and a half or two turns 
 on this shaft, is stretched by the weight 23, which offers a sufficient resistance 
 to any recoil. The slides are moved by the wheels 27 and 28 gearing with 
 the larger wheel 29. In order to regulate both the pressure and the amount 
 of colour, the points of junction, 16 and 17, are moved to a greater or less 
 distance from the point 15. The movement of the sieves is regulated by the 
 cam, 11, 30, which moves them by means of a shaft to which they are keyed. 
 
( rm"j> ^^H ^^^^_ 
 
 ^^H 
 
 554 
 
 DYEING AND CALICO PRINTING. 
 
 The furnishing-rollers are moved by gearing with pinions on the axes of the 
 rollers 8, 8. 
 
 The working of the perrotine may be described as follows : — The piece 
 moves on a length equal to the breadth of the pattern-blocks, along with the 
 blanket and back-cloth. The portion of the piece which issues from the third 
 block is fully printed ; what was under the second advances under the third ; 
 what was under the first moves to the second, whilst a fresh portion of 
 white calico comes up to the first. While the calico is thus moving the 
 sieves take the place which they hold in Fig. 24 ; the first on the right 
 hand rises, the second moves from left to right, and the third is lowered. All 
 three press on the furnishing-rollers, 8, where they take up the colour which 
 has been spread evenly by the brushes, 9. Meantime the sliding block-holders 
 move forward, and push the blocks against the sieves, so as to furnish them 
 with colour. At the same time the slides give the blocks a gentle movement 
 backwards, while the sieves deviate from their position. The blocks then 
 return, and are drawn back after having been pressed to a fresh part of the 
 colour surface. When these movements have simultaneously taken place the 
 action proceeds, the colour-sieves move back from before the blocks, and these 
 are pushed up against the latter, and print that part of the calico which is 
 stretched upon them. The machine is now again at the point at which the 
 description began. 
 
 The perrotine, as will be plain from the above description, is adapted for 
 patterns containing three distinct colours. It is extensively used in France 
 and Belgium, one machine doing the work of twenty skilled block-printers. 
 It executes some styles of work which the cylinder machine cannot execute 
 without the aid of the surface-roller. 
 
 In England the perrotine is in much less general use than in France. 
 The cylinder-machine, on the contrary, a Scotch invention, has received 
 its chief development in this country, and, except for a few particular 
 styles, has quite displaced hand-printing. One of them, managed by one 
 man, assisted only by two boys who attend to the colour troughs, performs as 
 much work as two hundred men and boys could do with the blocks. In some 
 styles a mile of cloth can be printed hourly by a single machine. 
 
 The following diagram gives a general idea of this system of printing 
 (Fig. 26). The design to be printed is. engraved on the surface of a hollow 
 copper roller, which is forced by pressure upon a stout mandrel of iron, which 
 serves it for an axle. To aid the transfer of the pattern to the calico to be 
 printed, the pieces are lapped around another large cylinder, which is rendered 
 elastic by a coating of stout woollen cloth. The pattern-roller presses the 
 calico against this elastic cushion, and consequently prints it as it revolves. 
 In the engraving A is the pattern-roller mounted on its mandrel, which receives 
 rotatory power from a wheel at its end, in connection with the steam or water 
 power of the works. B is a large iron drum, turning in bearings of the end . 
 frames of the machine. The pattern-roller, a, is pressed against this drum 
 by weights or screws, the weights acting steadily upon its brass bearings by 
 levers. Round the drum, b, an endless web of felt or blanket travels in the 
 direction of the arrow, and is carried round by the drum, b, which again is 
 turned by the friction of the cylinder, a. c is a wooden roller, covered with 
 cloth, and partly plunged in the colour mixture of the trough, d d. c is 
 
Plate VII. 
 
 Blocks Successively Applied to Produce the Different Shades 
 in a Flower. 
 
 Seepage 561. 
 
 Machine for Engraving the Cylinders used in " Machine-printing. 
 
1MMW m mm mm B Mmi M SB^ !■——__ 
 
 •»)*,**■ .w,*',h;A ^,y:*» 1 *i* .^ v*;^'.."-;^ '.•■, «•. >.«, w.^:.* -^ /'-, i.^ ^ 
 
 HI 
 
PRINTING. 
 
 555 
 
 preferably driven from the cylinder, a, by means of toothed wheels attached 
 to their ends, so that the revolution of c may be more rapid than that of a. 
 Since A is pressed upwards against b, the bearers of the trough and of its 
 roller are attached to the bearings of A, to preserve its contact with c ; b is a 
 sharp-edged ruler of gun-metal, steel, or German-silver, called the colour- 
 doctor, screwed between two stiffening bars of gun-metal ; the edge of the 
 doctor being slightly pressed at a tangent against the cylinder, A. The doctor 
 vibrates with a slow motion from right to left, so as to exert a delicate shaving 
 action upon the engraved surface as this revolves in the direction shown by 
 the arrow; c is another sharp-edged ruler, the lint-doctor, serving to scrape 
 off any filaments of cotton which may have come off the calico, and, which if 
 allowed to remain on the pattern-cylinder, might either smear the work, or 
 prevent the colour from filling up some of the lines of the engraving. This 
 lint doctor presses very slightly against the cylinder, a, and has no transverse 
 motion. The calico, shown by d, is carried in along with the blanket, a a, in 
 the direction of the arrow, and is passed on by the revolution of A, receiving 
 the pattern engraved upon that cylinder. The object of the colour-doctor is 
 
 Fig. 26. 
 
 to remove any excess of the colour mixture. Where a pattern contains more 
 than one colour it requires a compound machine, with a corresponding number 
 of cylinders mounted in one frame. In arranging these machines several 
 adjustments become necessary. It is most important to ensure a corre- 
 spondence between the parts of the design in the successive printing-cylinders, 
 for unless those of the second and following are accurately inserted in their 
 places and register with the first, the pattern produced on the cloth will become 
 confused. Fig. 27 is the end elevation of a 4-colour machine, and Fig 28 a 
 section. The same letters refer to both, a is the cast-iron frame, bolted to a 
 corresponding frame by the bolts, b, with an interval of 3 to 4 feet between ; 
 c is the hollow iron pressure cylinder, about 2 feet in diameter, and between 
 3 and 4 feet long, according to the width of the cloth to be printed. D are 
 the copper rollers, the width of a piece of cloth ; e are wrought-iron mandrels, 
 on which the copper rollers are forced. The mandrel is about 4 inches diameter 
 where the roller fits on, but its journals are of less diameter. The pattern- 
 roller is made with a projecting piece inside, about i inch broad and \ inch 
 deep, extending all the width of the roller. This so-called " tab " fits in a 
 slot cut in the mandrel, which thus causes it to turn without slipping on the 
 
■ 
 
 ■■■■ 
 
 ^^^^^^^^i 
 
 556 
 
 DYEING AND CALICO PRINTING. 
 Fig. 27. 
 
 Fig. 28. 
 
PRINTING. 
 
 557 
 
 mandrel. The pressure cylinder or bowl, c, rests with its gudgeons in bushes, 
 which can be shifted up and down in slots of the side cheeks, a. These 
 bushes are suspended from powerful screws, F, which turn in brass nuts made 
 fast to the frame, a. These screws counteract the upward pressure of the 
 two lowest rollers, and enable the bowl to be lifted out of the way of the 
 rollers when they have to be removed, o g are sliding pieces, moving in arms 
 of the framework by means of screws, h h. These sliding pieces carry the 
 bearings of the mandrels, and to them are also attached the colour troughs 
 and doctors. The screws, h', work in female screws, i', forming part of a 
 system of jointed levers, K. These levers serve to give an additional elastic 
 pressure to the rollers, D. There are four pairs of levers, each bearing upon 
 
 Fig. 29. 
 
 one mandrel. The two highest rollers are pressed against the cylinder by the 
 compound levers, k\ which have attachments to the arms of the framework 
 at/, and to the inside of the main framework at g, and m" as fulcrums ; the 
 screws, h" h", working in female screws, 1" 1", as in the other set of levers. 
 For convenience in removing the rollers, colour boxes, &c, these levers are 
 fitted with a hinged piece, n, in a socket, 0, on the top of which work the 
 screws, / /, which by means of the female screw in the lever, k k", serve further 
 to regulate the pressure ; the lever, k" k, is shown as when the machine is 
 printing, but when the rollers are to be removed the lever is lifted by the 
 handle and the hinged piece, N, pulled over, the lever with its burden being 
 
Hfr-iii 
 
 fiws 
 
 ■ 
 
 58 
 
 DYEING AND CALICO PRINTING. 
 
 I 
 
 then lowered down. The weighting of these levers, which are partly outside 
 the machine, is seen in Figs. 27 and 28. l are weights, q colour boxes, their 
 bottoms and sides made of sheet-copper and the ends of gun-metal ; in each 
 end is a slot to receive the brass journals of the wooden furnishing rollers, P, 
 which are lapped with a few layers of coarse calico, and, revolving in the 
 colour and against the pattern-rollers, n, supply them equally all ever with the 
 colour; any excess of colour being removed by the doctors, T. These are thin 
 blades of some appropriate metal, often steel, but sometimes German-silver, 
 which are mounted in doctor-shears, that is, plates of metal screwed together 
 with bolts. The shears have journals, which rest in bearings, movable back- 
 wards and forwards by the screws, s ; the doctors are kept in close contact 
 with the pattern-rollers by levers and weights, for the arrangement of which 
 see Fig. 29, where a b c arc the levers attached to the doctor-shears. On 
 the ends of these levers weights are hung, and by this means the doctors are 
 forcibly pressed against the pattern-roller. After printing its pattern on the 
 piece the roller, D, is cleaned from dust or filaments by the lint-doctors, u, 
 pressed against the roller by the screw, s, Fig. 28. The colour boxes are 
 mounted on wooden boards, and tightened up against the roller by the screws, 
 wwandRR. The lower pair of colour boxes are removed from the copper 
 roller when not in use by the handles, v, after removing the screws, w w. 
 There is a toothed wheel slipped on to each mandrel, working into a toothed 
 wheel on the axle of the furnishing-roller, which ensures the pattern-roller 
 and furnishing-roller always working together. By an excentric, fixed on the 
 axis of the pressure bowl and connected with each colour doctor, they receive 
 a vibratory movement, which hinders them from being worn down irregularly. 
 Sometimes in machines for more than four colours the colour box is dispensed 
 with, and a doctor placed in a covered frame is applied to the pattern-roller 
 instead. In this arrangement the doctor forms the bottom of the colour 
 receptacle, and is strongly pressed against the roller, the curved frame stopped 
 off at the sides with a piece of copper curved to fit both roller and frame, and 
 which is padded with a piece of folded cotton cloth, forms the colour box. 
 Such a box takes up little room and consumes little colour. The roll 
 of calico is shown at a, wound on the wooden roller, b, the axle of which 
 rests in bearings at the end of the arms. The calico passes under a small 
 wooden roller, next over a square iron bar, and next against the scrimping-bar, 
 Y, thence over the wooden roller, a, round which also pass the piece of grey 
 cotton, J, and the woollen blanket, e. The scrimping-bar is made of iron or 
 brass with a curved surface furrowed by grooves, cut right and left fiom the 
 centre. By passing over this bar the cloth is stretched equally from the 
 centre, and creases are removed. To keep the piece constantly stretched the 
 roller, b, is fitted with a wooden pulley, round which passes a leather strap, 
 one end of which is secured to the framework, and to the other is attached a 
 weight. The friction of the strap against the pulley produces a retarding 
 action, and keeps the piece stretched. 
 
 Fig. 30 shows a 12-colour machine, and Fig. 31a 20-colour, by Messrs. 
 Gadd and Hill, of Manchester. 
 
 The surface roller machine executes similar styles of work to those pro- 
 duced by the perrotine. Here the pattern-cylinder is in relief like the hand 
 blocks. Fig. 32 is an 8-colour machine of this class, by Messrs. Gadd and 
 Hill, a A is here the framework ; b b the bowl or cylinder, which is hollow, 
 
PRINTING. 
 
 559 
 
 Fig. 30. 
 
 Fig. 31. 
 

 ^H 
 
 '4"^'-\k 
 
 560 
 
 DYEING AND CALICO PRINTING. 
 
 and made with arms inside ; c c are the surface-rollers supplied with colour by 
 the endless web or sieve,//, revolving round the wooden tension-rollers, dde. 
 The roller, e, is screwed down so as to press the sieve on the furnishing- 
 roller, f, which revolves in the copper-colour box, g ; the two tension-rollers 
 next to the surface-roller move in slides, so that by means of the screw, h, the 
 sieve can be pressed against the surface-roller; on leaving the furnishing- 
 roller, f, the sieve is wiped by the doctor, 1. The printing-roller is in relief, 
 and there is consequently no need for the levers of the common machine. 
 The surface-machine is well adapted for woollen fabrics, and the colours, being 
 laid on the top of the cloth, have a very rich appearance. The outlines are 
 apt to be not well defined. 
 
 The general routine of machine-printing is as follows: — The pieces to be 
 pnnied, generally in lots of foity, are wound on a wooden roller, as shewn in 
 
 Fig. 32. 
 
 the above engravings. Last of all a few yards of common coarse cotton kept 
 for this purpose are attached. This serves for the printer to fit the pattern on. 
 The printer's assistant stands behind, guiding the cloth evenly, and cutting 
 off any loose threads. The printer stands in front, and, after he has fitted his 
 pattern, attends to the colour boxes, and watches to prevent any irregularity 
 in working. After thirty to forty pieces have been run through, the machine is 
 stopped, the doctors are removed, and the edges are re-touched with the file. 
 
 The drum which revolves in contact with the pattern-cylinder is covered 
 first with a coarse, stout cloth, which is wrapped tightly around it to the 
 thickness of J inch. Over this is drawn the blanket, a very important part of 
 the machine. It is a thick woollen tissue, about 40 yards long, very uniform 
 in texture, thickness, and elasticity. One blanket will generally serve during the 
 
COLOUR PRINTING. 
 
 56i 
 
 printing of 10,000 pieces. A variety of india-rubber blankets have been made 
 and brought into use. Some of these consist of mercerised calico cemented 
 together with caoutchouc. These blankets will serve for 20,000 pieces. Still 
 for certain styles the old woollen blanket is still preferred. 
 
 We have not space to enter into a description of the complicated and 
 delicate machinery used in transferring the desired patterns from the flat 
 surface upon which they are first designed to the copper cylinders used in 
 machine printing. The same reason must be given for omitting a notice of the 
 machinery used for running the pieces, after printing, on into the drying room, 
 the machines for stitching together the ends of the pieces to be printed in one 
 roll, the apparatus for freeing the cloth about to be printed from dust and ends 
 of thread, &c. 
 
 The colour-house, the place where the Ingredients needed in the various 
 operations of a print-works are prepared and mixed, is a large, well-ventilated 
 room on the ground floor. Along one side of it runs a range of colour pans, 
 of various sizes (Fig. 33). These pans are supplied with water, and can be 
 heated or brought to a boil by means of steam. As a rule they turn on pivots, 
 so that they may be the more easily emptied out and cleaned. The range 
 
 Fig. 33. 
 
 EE^ 
 
 shown in the figure consists of a suit of eight pans, each fitted with a steam- 
 jacket. They vary in size from 1 to 28 gallons, a is a pipe of copper, closed 
 at one end, and open at the other for the entrance of the steam, which 
 descends through the vertical pipe, b, as far as the stuffing box, c, through 
 which it passes into the steam-jacket of the pan, and escapes by the waste, 
 pipe, d. Each pan is fitted with a similar steam-pipe, which can be separately 
 opened or shut off by means of a tap. c is a horizontal pipe, by means of 
 which cold water can be supplied to each pan for cooling. The waste-pipe 
 has steam-tight connections to fit the taps fixed at the bottom of each pan. 
 These can be unscrewed when it is necessary to incline or to invert the 
 pan, and afterwards re-adjusted. 
 
 The ingredients for any colour required are placed in one of these pans, 
 and constantly stirred all the time that they are being boiled and incorporated. 
 This operation, which is essential to the production of a good colour, was 
 generally performed by boys called " gum-sticks." Now the colour pans are 
 frequently fitted up with mechanical agitators. When all the ingredients 
 necessary to form a colour have been dissolved and thoroughly incorporated 
 the steam is cut off, and cold water admitted into the steam-jacket to cool the 
 
 2 o 
 
■ 
 
 
 H 
 
 ■BE 
 
 562 
 
 DYEING AND CALICO PRINTING. 
 
 mixtures. The pan is then emptied, and the colour carefully strained into a 
 suitable tub or bowl. The object of straining is to remove all gritty particles 
 introduced by any of the materials, which would have a very injurious effect 
 if suffered to remain. 
 
 A straining machine, invented and patented by Dollfus and Mieg, has been 
 introduced into this country, and is used with success. It is represented in 
 
 Fig. 34. 
 
 Fig. 
 
 35- 
 
 Figs. 34 and 35, the former giving the side and the latter the front elevation. 
 A is the cylinder, strengthened above and below by the belts, b and a. The 
 bottom plate of the cylinder, which is movable, is supported by the hooks, c. 
 This plate is removed when required by means of springs fitting on D, and 
 acting on two of the hooks, c, so as to withdraw them from under the grating, 
 b. Upon a lies a second ring, d, supporting the handle, e. The tops of the 
 
THICKENERS. 
 
 563 
 
 hooks, c, lie upon four inclined planes fixed on the ring, d. The action is as 
 follows: — On turning d to either hand the plate, b, which is covered with a 
 suitable straining cloth or tissue of very fine wire gauze, is brought close up 
 to the end of the cylinder, and if this is then filled with the colour to be 
 strained, and the piston, m, worked by the pulley, e, the wheels, f, g, h, i, k, and 
 the rackwork, L, presses it through the filter. It is possible that an adaptation 
 of the Needam filter press might answer the same purpose. 
 
 The subject of thickeners has been already discussed on pp. 17, 66, and 75, 
 to which the reader is, therefore, referred. A few additional remarks are, 
 however, needed. Certain thickenings, such as flour and starch, are insoluble 
 in cold water, others, like the gums, are soluble in cold water, while certain 
 mixed thickeners are partially soluble only. These distinctions are highly 
 important as to their action. A smaller weight of the insoluble thickenings 
 will produce as high a degree of tenacity as a larger of the soluble class. 
 The following quantities may be regarded as respectively equivalent: — 
 
 Starch 20 ozs. per gal. 
 
 Flour 22 ,, ,, 
 
 Gum tragacanth 10 to 12 ,, „ 
 
 Calcined farina 8 to gibs. ,, 
 
 As a rule the smaller the quantity of thickening needed the darker is the 
 resulting colour. What may be called the penetrating power of different 
 thickeners is also a point of importance. Generally speaking, the more the 
 colours can be kept to the face side of the cloth, and prevented from 
 penetrating into the thickness of the tissue, the greater is the economy, and 
 the finer and clearer the effects produced. Great judgment is required in 
 combining various thickeners together for any desired effect. Combinations 
 unskilfully made often separate, and in consequence work badly. Chemical 
 combination between the thickening on the one hand, and the colours or 
 mordants on the other, is to be avoided as far as possible. It produces loss, 
 and may sometimes totally spoil a colour. Saccharine matters cannot be 
 safely added as thickeners to colours containing metallic salts, since they 
 hinder the combination which would otherwise take place between the mordant 
 and the metallic colouring matter. Starch, likewise, if used to thicken very 
 acid colours, may, on standing for a few days, become partially converted into 
 starch-sugar or glucose, and may then have the effect of masking the mutual 
 reactions of the various ingredients. As an interesting instance of such 
 " masking," we may mention that a sample of nitrate of iron has been known 
 to produce no black colouration when mixed with logwood or gall-liquor. A 
 strong smell of bitter almonds explained the mystery. The nitric acid used 
 in preparing the nitrate of iron was mixed with a residual product from the 
 manufacture of nitro-benzol, and a small quantity of the latter body effectually 
 prevented the reaction of the nitrate of iron and the tannin. 
 
 From such instances it will be seen that no collection of receipts, however 
 varied, complete, and valuable, will suffice to make a colour-mixer. Extensive 
 chemical knowledge, long experience, a habit of minute and accurate observa- 
 tion, and great fertility in resources are needed. 
 
 The styles of calico printing are roughly grouped under eleven heads. 
 " Roughly," we say, since each of these has its subdivisions and its modifi- 
 cations, and since many effects are produced by a combination of processes 
 
BBBHRHB BBHHHB 
 
 564 DYEING AND CALICO PRINTING. 
 
 belonging to two or more styles, to each of which they might with equal 
 justice be ascribed. These styles are — 
 
 I. Madder Colours, with several Variations. 
 
 In its plainest form one or two mordants— namely, red liquor and iron 
 liquor — are printed on the goods, which are then dyed in the madder-beck. 
 The result is a white ground, with a pattern which may be black ; red ; black 
 and red ; black and two shades of red, the red liquor having been applied in 
 different strengths ; red, black, and purple, the purple being produced by iron 
 liquor weaker than is required to give a black. Chocolate may be added by 
 causing both red and iron liquor to be applied to the certain parts of the 
 design. Brown is also obtained by the introduction of catechu. 
 
 Another variation of the madder style is more complicated : — Iron liquor, 
 red liquor, or combinations of both, are printed on, and also lime-juice, 
 technically called "acid." The piece is then printed over — technically called 
 " covered " — with a fine pattern, in purple or light chocolate, and dyed up 
 with madder. The red mordant used in this process is of a peculiar kind, 
 known as resist-red. Where the resist-red and the lime-juice have been 
 printed on, the purple and chocolate are prevented from fastening, and there 
 remain, consequently, pure red and clear white portions, whilst the rest is 
 taken up with the fine cover pattern. Sometimes a very weak purple is 
 44 blotched " or padded all over, when the only white portions remaining are 
 those where the acid has been printed on. This style obviously admits of the 
 production of a great diversity of effects. 
 
 A further variation is the French pink style, which consists entirely of 
 different shades of red and pink. Red mordant of different strengths, if more 
 than one shade of red or pink be required, are printed on, and also acid (lime- 
 juice) for the production of whites. The whole may then be either " covered " 
 or blotched with the appropriate mordant for a very pale red. The whole is 
 then dyed in the madder-beck and cleared with soap, as will be described 
 below. All the variations of the madder style produce fast colours, which, in 
 domestic phraseology, wash well. 
 
 II. Garancin Colours. 
 This style is very similar to the preceding, garancin being used instead of 
 madder. The colours used are generally heavier and darker, deep reds, 
 browns, and oranges predominating. Catechu is largely used as an accessory. 
 In this style the goods do not undergo a final treatment with soap, and the 
 colours are less permanent than those dyed with madder. 
 
 III. Reserved Style. 
 This style may be termed a combination of either of the two former with 
 the eighth (Steam-Colour Style). After the madder-work has been dyed and 
 cleared, a further design — in yellow, blue, or green — is blocked in, and fixed by 
 the steaming process. Sometimes a " resist paste " is blocked on, so as to 
 protect the whole or certain portions of the pattern originally produced, and 
 a small pattern in drab, slate, buff, &c, is printed over. all. Or, instead of 
 colours mordants are printed on in like manner, and the goods are subsequently 
 dyed in cochineal, bark liquor, &c, which of course only take effect where 
 
STYLES 
 
 565 
 
 these mordants have been attached. Sometimes white portions are protected 
 by the reserve paste, and various lively colours are subsequently blocked in 
 upon these. This style produces an extreme variety of effects. 
 
 IV. Padding Styles. 
 The whole cloth is padded all over with a suitable mordant. A design is 
 next printed on in acid (discharge), and the goods are dyed. The result is 
 white spots — when the acid has been printed on — upon aground of one uniform 
 colour. Upon the white discharged spois steam-colours or pigment-colours 
 may again be printed. 
 
 V. Indigo-Blues. 
 A reserve paste, which may be accompanied by so-called yellow or orange 
 mordants (see below), is printed upon the goods, which are then dyed up to 
 the required shade in the indigo-vat. The indigo is not deposited upon the 
 spots where the reserve has been printed. Yellows and oranges, where 
 required, are brought out by passing through a solution of bichrome, which 
 combines with the salt of lead contained in the yellow and orange mordants. 
 The result is a deep blue ground colour, with designs in white, yellow, or 
 orange, upon which, again, steam-colours may be blocked in. 
 
 VI. China Blues. 
 In this style mixtures containing indigo are printed upon the white cloth, 
 and the indigo is then fixed, producing a blue design upon a white ground. 
 
 VII. Turkey Red with Discharges. 
 The cloth is first dyed Turkey red, upon which certain discharge mixtures 
 are printed. The goods are next worked in a solution of bleaching-lime, 
 which, a&ing where the mixtures have been printed on, disharges the red. 
 The result is, consequently, a white design upon a red ground. But along 
 with the discharge there is frequently printed, on a pigment-colour, a mixture 
 for a black, or a salt of lead. In the latter case the pieces are subsequently 
 passed through a solution of bichrome, which brings up a yellow. This style 
 may therefore show designs in a variety of colours, the ground being always 
 Turkey red. 
 
 VIII. Steam-Colours. 
 The goods in this style are generally prepared with a per-salt of tin, by 
 means of working in a solution of stannate of soda, followed up by a passage 
 through a dilute acid liquid technically called " sours." The mixtures printed 
 on consist of colouring matters, — often extracts of dye-woods, — mordants, 
 acids, and salts. After printing, the pieces are exposed to steam in an appa- 
 ratus described below, washed, and dried. This style is peculiarly applicable 
 to animal fibre, — woollen and mixed tissues, and frequently also silks, are 
 thus treated. It is also the general style for the coal-tar colours. 
 
 IX. Spirit-Colours. 
 These agree in their general character with steam-colours, but contain larger 
 proportions of acids and metallic salts. After printing they are not steamed, 
 but merely dried very carefully, exposed to the air for twenty-four to forty-eight 
 hours, and washed. 
 
W&$$ 
 
 8BBWWM 
 
 5 66 
 
 DYEING AND CALICO PRINTING. 
 
 X. Bronzes. 
 This style, formerly much admired, but now falling into disuse, has for its 
 main feature a ground colour of peroxide of manganese, upon which suitable 
 discharges, pigments, &c, were printed on. The manganese-brown was thus 
 removed or replaced, the result being a white, yellow, green, pink, &c, pattern 
 on a deep brown ground. 
 
 XI. Pigment-Colours. 
 
 In this style colours ready-formed and insoluble, such as those used by 
 artists, are fastened upon the fibre by the aid of mediums, — which might 
 rather be called cements than mordants, — such as albumen, the fixation being 
 completed by steaming. 
 
 First Style.— Madder. 
 The madder styles have for a long time played the most important part in 
 calico-printing. A leading characteristic of these styles is that the mixtures 
 printed on to the calico — the " colours," technically so-called — are not colours, 
 but mordants, capable of combining both with the tissue and the colouring 
 matter, and modifying as well as fixing the latter. The most important mor- 
 dants in the madder style are the acetates or pyrolignites of alumina and iron. 
 
 No. 1. Red Liquor. — See p. 277. 
 
 No. 2. Black Liquor, or Iron Liquor. — See p. 291. 
 
 No. 3. Purple Fixing Liquor. — 
 
 Water 7i gals. 
 
 Acetic acid 1$ ,, 
 
 Sal-ammoniac gibs. 
 
 Arsenious acid 9 >> 
 
 Boil till the arsenic is dissolved, and let the solution stand till any turbidity 
 is deposited. Decant off the clear. 
 
 No. 4. Purple Assistant Liquor (Mercer and Barnes's Patent). — 
 
 Potato starch 100 lbs. 
 
 Water 37* gals. 
 
 Nitric acid, at 6o° Tw 123 ,, 
 
 Manganese, black oxide 4 ozs. 
 
 When the reaction is over and the nitric acid destroyed add — 
 
 Pyroligneous acid 50 lbs. 
 
 No. 5. Purple Fixing Liquor. — 
 
 Water 2 gals. 
 
 Carbonate of soda (crystals) 25 lbs. 
 
 Arsenious acid 22i ,, 
 
 Dissolve at a boiling heat, and add — 
 
 Crude acetic acid (pyroligneous), at 120 F 50 gals. 
 
 Allow the whole to stand for a few days ; draw off the clear liquid, and 
 
 add— 
 
 Spirits of salt, at 32 Tw 3 quarts. 
 
MADDER STYLES. 567 
 
 No. 6. Black (Machine).— 
 
 Iron liquor, at 24 Tw 4 gals. 
 
 Pyroligneous acid 4 ,, 
 
 Water 4 ,, 
 
 Flour 24 lbs. 
 
 Work up the flour with a little of the liquids into a smooth, thin paste, per- 
 fectly free from lumps or clots ; add the rest of the liquid, boil, and add — 
 
 Oil 1 pint. 
 
 No. 7. Black (Machine) Garancin. — 
 
 Water 7i gals. 
 
 Iron liquor, at 24 Tw. 3 ,, 
 
 Purple fixing liquor, No. 5 ij ,, 
 
 Flour 24 lbs. 
 
 Oil 1 pint. 
 
 See also p. 291. 
 
 No. 8. Brown Standard. — 
 
 Water 50 gals. 
 
 Catechu 200 lbs. 
 
 Boil for six hours, and add — 
 
 Acetic acid - . . 4J gals. 
 
 Water, to make up 50 gals. 
 
 Let the whole stand for two days, and decant the clear. Heat it to 130 F., 
 and add — 
 
 Sal-ammoniac 96 lbs. 
 
 Dissolve, and let settle for forty-eight hours. Decant the clear, and thicken 
 with 4 lbs. gum Senegal per gallon. 
 No. 9. Brown (Machine). — 
 
 No. 8 4 gals. 
 
 Acetate of copper (see below, No. 10) 1 gal. 
 
 Acetic acid 2 quarts 
 
 Gum Senegal water (4 lbs. per gallon) 4 gal. 
 
 No. 10. Acetate of Copper (referred to in No. 9). — 
 
 Sulphate of copper 4 lbs. 
 
 Acetate of lead 4 ,, 
 
 Hot water 1 gal. 
 
 Dissolve, allow the turbidity to subside, and dilute to 16 Tw. with water. 
 No. 11. Brown (Machine). — 
 
 No. 8 7 gals. 
 
 No. 10 i£ „ 
 
 Gum red (see below, No. 12) i£ ,, 
 
 No. 12. Gum Red. — 
 
 Red liquor, at 18° Tw 3 gals. 
 
 Gum-substitute 12 lbs. 
 
 Boil up, and stir well till all is dissolved. 
 No. 13. Brown (Machine) Garancin. — 
 
 No. 9 2 gals. 
 
 Gum-substitute water (at 4 lbs. per gallon) .... 1 gal. 
 

 5 68 DYEING AND CALICO PRINTING. 
 
 No. 14. — 
 
 No. 8 2 gals. 
 
 Gum substitute water (at 4 lbs. per gallon) .. .. 3$ ,1 
 
 Acetic acid 3 quarts 
 
 No. 10 3 „ 
 
 No. 15. Madder Brown Standard (another, see No. 8). — 
 
 Water 70 gals. 
 
 Catechu 350 lbs. 
 
 Boil for ten hours ; then add — 
 
 Sal-ammoniac 100 ,, 
 
 Acetic acid 9 gals. 
 
 Gum Senegal (ground) as required to thicken. 
 
 No. 16. Brown Colour from above. — 
 
 No. 15 2 gals. 
 
 Acetic acid 1 pint 
 
 Acetate of copper (No. 10) 2 pints. 
 
 No. 17. Medium Brown.— 
 
 Catechu i\ lbs. 
 
 Sal-ammoniac 6 ozs. 
 
 Water 1 quart. 
 
 Boil till dissolved, and add— 
 
 Nitrate of copper, at 8o° T\v 12 ozs. 
 
 Acetate of copper (No. 10) 8 ,, 
 
 Gum water 4 gal. 
 
 No. 18. Madder Brown, to Resist Heavy Covers of Purple. — 
 
 Catechu i lb. 
 
 Sal-ammoniac \ ,, 
 
 Lime juice, at 8° Tw 1 quart 
 
 Nitrate of copper, at 8o° Tw 2 J ozs. 
 
 Acetate of copper (No. 10) i£ ,, 
 
 Gum Senegal 1 lb. 
 
 No. 19. Brown for Garancin, Dark. — 
 
 Catechu 9 lbs. 
 
 Sal-ammoniac 1} „ 
 
 Water 1 gal. 
 
 Boil, strain, and add — 
 
 Gum water (at 4 lbs. per gallon) ij gals. 
 
 Nitrate of copper, at 84 Tw 1 quart 
 
 Acetate of copper (No. 10) 1 ,, 
 
 Lighter browns can be obtained by increasing the proportion of gum-water. A 
 
 redder tone, when required, is given by adding 1 quart of red liquor to about 
 10 quarts or more of the above colour. 
 
 No. 20. Medium Brown {for Garancin). — 
 
 Catechu 3 lbs. 
 
 Sal-ammoniac 10 ozs. 
 
 Water 2 quarts 
 
MADDER STYLES. 569 
 
 Boil, strain, and add — 
 
 Gum-water 1 gal. 
 
 Nitrate of copper, at 8o° T\v ii pints 
 
 Acetate of copper (No. 10) , .. ij gills. 
 
 No. 21. Brown (Garancin).^- 
 
 Catecliu 2 lbs. 
 
 Water 53 ozs. 
 
 Sal-ammoniac 6£ ,, 
 
 Boil, strain, and add — 
 
 Gum-water I0 6 ozs. 
 
 Nitrate of copper, at 8o° Tw i6£ ,, 
 
 Acetate of copper j pint. 
 
 Red liquor may be added to give a redder tone. 
 No. 22. Brown for Madder. — 
 
 Catechu 2 lbs. 
 
 Weak acetic acid 1 quart 
 
 Sal-ammoniac ^ lb. 
 
 Acetate of copper 1 pint. 
 
 Decant the clear liquor for use. (See also p. 292). 
 No. 23. Chocolate [Machine). — 
 
 Iron liquor, at 24 Tw 3 gals. 
 
 Red liquor, at 18 Tw 9 ,, 
 
 Flour 24 lbs. 
 
 Oil 1 pint. 
 
 No. 24. Chocolate. — 
 
 Iron liquor, at 24° Tw 1 gal. 
 
 Red liquor, at 18 Tw 6 gals. y 
 
 Flour 14 lbs. 
 
 Oil 1 gill. 
 
 No. 25. Chocolate for Garancin. — 
 
 Red liquor, at 18° Tw 4 gals. 
 
 Iron liquor, at 8* Tw. 2 \ •■> 
 
 Flour 10 lbs. 
 
 Logwood liquor, to sighten 1 pint. 
 
 The reddest chocolate in regular use is made with about 1 quart of iron 
 liquor, at 24 Tw., to 30 quarts of red liquor, at 18 Tw. 
 No. 26. Drab (Machine). — 
 
 No. 8 4 gals. 
 
 Protochloride of iron (protomuriate), at 9 Tw. . . 1 gal. 
 
 No. 10 (acetate of copper) 3 gals. 
 
 Gum-substitute water (4 lbs. per gallon) 1 gal. 
 
 If intended for garancin, 4 gals, of gum-substitute water are used. 
 No. 27. Drab (Machine). — 
 
 No. 26 lo gals. 
 
 Muriate of iron, at 9° Tw 1 gal. 
 
 Gum-substitute water, at 4 lbs. per gallon . . . . 10 gals. 
 
 No. 10 (acetate of copper) 11 „ 
 
■HHH1 
 
 <*M^--W? 
 
 HHHW 
 
 570 DYEING AND CALICO PRINTING. 
 
 No. 28. Farina Gum-Water, Dark. — 
 
 Water 5 gals. 
 
 Dark calcined farina 30 lbs. 
 
 Boil well. 
 
 No. 29. Fawns. — Add to No. 26 or No. 27 T 'jth of red liquor, more or less, 
 according to the shade required. 
 
 No. 30. Purple, Madder {Machine). 
 
 Iron liquor, at 24 Tw 2 gals. 
 
 No. 5 4 „ 
 
 No. 28 8 „ 
 
 No. 31. Purple, Madder (Machine). — 
 
 Iron liquot, at 24° Tw 2 gals. 
 
 No. 5 4 „ 
 
 No. 28 24 ,, 
 
 No. 32. Purple (Garancin). — The following thickener is added, in various 
 proportions, to the iron liquor : — 
 
 Light British gum 40 lbs. 
 
 Water 16 gals. 
 
 No. 5 2 „ 
 
 Boil well together, draw off, and allow the whole to stand for three or four 
 days. Of this, from 8 to 30 gallons, and upwards, may be added to 1 gallon 
 of iron liquor. 
 
 No. 33. Padding Purples. — The thickener is prepared as follows : — 
 
 Water 13 \ gals. 
 
 No. 5 2 „ 
 
 Logwood liquor, at 8* Tw \ gal. 
 
 Flour 18 lbs. 
 
 Boil up, and add — 
 
 No. 28 i\ gals. 
 
 One part of iron liquor, at 24 Tw., is mixed with any required amount of this 
 
 thickening, according to shade required. Block-colours are made by diluting 
 
 the above. (See also p. 291). 
 
 No. 34. Red (Machine), Dark. — 
 
 Red liquor, at 18 Tw 6 gals. 
 
 Flour 12 lbs. 
 
 No. 35. Red Liquor, Standard. — 
 
 Alum 20 lbs. 
 
 Sugar of lead, white 12J „ 
 
 Boiling water 5 gals. 
 
 Stir up until dissolved, allow the mixture to settle, and draw off the clear 
 
 liquor. (See also pp. 283 and 284.) 
 
 No. 36. Red, Pale (Machine). — 
 
 No. 35 1 gal. 
 
 Gum-substitute water (30 lbs. gum-substitute in ) , 
 
 r 3 gals. 
 10 gals, water) J 
 
MADDER STYLES. 
 
 No. 37. Red-Resist, Dark (Machine). — 
 
 Resist-red liquor, at 18 T\v 12 gals. 
 
 Flour 24 lbs. 
 
 Boil well, and when almost cold add — 
 
 Tin crystals 12 lbs. 
 
 Used to resist a chocolate " cover." 
 
 No. 38. Resist-Red Liquor. — 
 
 Acetate of lime liquor, at 24 Tw 90 gals. 
 
 Sulphate of alumina 272 lbs. 
 
 Ground chalk 34 ,, 
 
 No. 3811. Resist-Red Liquor. — 
 
 Water 1 gal. 
 
 Alum 5 lbs. 
 
 Acetate of lead 2j lbs. 
 
 Soda crystals i lb. 
 
 No. 39. Resist-Red, Dark (Machine). — 
 
 Resist-red liquor, at 18 Tw 6 gals. 
 
 Flour 12 lbs. 
 
 Treat as in No. 37, but add — 
 
 Tin crystals 3 lbs. 
 
 Used to resist a purple cover. 
 
 No. 40. Resist-Red, Light (Machine). — 
 
 Resist-red liquor, at 5 Tw 12 gals. 
 
 Flour g lbs. 
 
 Boil, and when cool add — 
 
 Tin crystals 2 lbs. 
 
 No. 40. Red, Full (Garancin). — 
 
 Red liquor, at 18 Tw 5 gals. 
 
 Water 1 gal. 
 
 Flour 12 lbs. 
 
 No. 41. Red, Resist, Garancin (Machine). — 
 
 Resist-red liquor, at 14 Tw 6 gals. 
 
 Flour 12 lbs. 
 
 Boil, and when cool add — 
 
 Tin crystals 4I lbs. 
 
 This mixture is used to resist chocolate covers. 
 
 No. 42. Red, Resist, Garancin (Machine). — 
 
 Resist-red liquor, at 14 Tw 6 gals. 
 
 Flour 12 lbs. 
 
 Boil, and when nearly cold add — 
 
 Tin crystals 2\ lbs. 
 
 Used for resisting purple covers. 
 
 57 * 
 
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 ^g^^^H^^^^^^HHi 
 
 MWWWWWMWM 
 
 572 DYEING AND CALICO PRINTING. 
 
 No. 43. J?^, Resist, Garancin (Machine). — 
 
 Red liquor, at 18 T\v 2 gals. 
 
 Starch z\ lbs. 
 
 Peachwood liquor , 1 gill. 
 
 Boil, and when cool add — 
 
 Tin crystals \ lb. 
 
 Used for resisting light chocolate "covers." (See also pp. 287, 28S, and 289.) 
 
 Mordants, Discharges, Reserves, Covers, &c. 
 No. 44. Alkaline Red Mordant. — 
 
 Alum (not ammoniacal) 10 lbs. 
 
 Boiling water 5 gals. 
 
 Dissolve and add — 
 
 Caustic soda-lye, at 70 Tw f gal. 
 
 Add cold water to make up 12 gals., allow the precipitate to settle, and wash 
 by decantation till the washings are tasteless. Filter, remove the precipitate 
 from the filter, and dissolve it in 5 pints caustic soda-lye, at 70 Tw. Boil, 
 make up to 3 gals., add 9 lbs. of dark gum substitute, and boil again. 
 
 No. 45. Light Red Alkaline Mordant. — 
 
 No. 44 1 gal. 
 
 Dark gum-substitute water g lbs. 
 
 No. 46. Alkaline Pink Mordant. — 
 
 Caustic potash-lye, at 54° Tw 40 gals. 
 
 Sulphate of alumina (patent- or cake-alum) . . . . 140 lbs. 
 The lye is heated in an iron boiler, and the sulphate of alumina added by 
 degrees, with frequent stirring. The yield is about 45 gals., at 34 Tw. It is 
 thickened with dark gum-substitute. 
 
 No. 47. Alkaline Light Pink Mordant. — 
 
 Caustic potash-lye, at 41° Tw 25 gals. 
 
 Alum (potash) go lbs. 
 
 Dissolve in the same manner as above. (See also p. 278.) 
 No. 48. " Acid " (Lime-juice Mixture). — 
 
 Lime-juice, at 8° to io° Tw 1 gal. 
 
 Starch 1 lb. 
 
 Boil, and stir till dissolved. 
 No. 49. "Acid." — 
 
 Lime-juice, at 20 Tw 1 gal. 
 
 Starch 1 lb. 
 
 No. 50. "Acid." — 
 
 Lime-juice, at 30* Tw 1 gal. 
 
 Starch 1 lb. 
 
 These acids are sometimes thickened with gum-substitute. 
 No. 51. Acid Discharge. — 
 
 Lime-juice, at 22 Tw 1 gal. 
 
 Bisulphate of potash 1 lb. 
 
 The clear liquor is run off from the sediment, filtered, and thickened with 1 lb. 
 starch. 
 
 No. 52. Acid Discharge — 
 
 Lime-juice, at 28° Tw 1 gal. 
 
 Bisulphate of potash 2 lbs. 
 
MADDER STYLES. 573 
 
 Filter, and thicken with — 
 
 Dark British gum 5 lbs. 
 
 For Reserve Pastes see Style III., Nos. 1 and 2. 
 No. 53. Gall Liquor. — 
 
 Gall nuts, ground 28 lbs. 
 
 Acetic acid 2 gals. 
 
 Water 12 ,, 
 
 Let stand for two days, stirring occasionally, and then filter. 
 No. 54. Hazel Statidard. — 
 
 Brown, No. 9 1 gal. 
 
 Bark liquor, at io° Tw £ ,, 
 
 Logwood liquor, at 12° Tw 1 pint. 
 
 Cochineal liquor, at 8° Tw 1 quart. 
 
 No. 55 (see below) 16 ozs. measure. 
 
 Gum Senegal water (at 6 lbs. per gal.) 1 gal. 1 pint. 
 
 No. 55.— 
 
 Nitrate of iron, at 8o° Tw 1 gal. 
 
 Nitrate of copper, at ioo° Tw » „ 
 
 No. 56. Buff Standard. — 
 
 Water 2 gals. 
 
 Copperas 10 lbs. 
 
 Acetate of lead (brown) 2J „ 
 
 Ditto ditto (white) ij „ 
 
 No. 57. Another Buff. — 
 
 Water 5 gals. 
 
 Copperas 20 lbs. 
 
 Brown sugar of lead 10 ,, 
 
 The clear liquid drawn off after solution and settling is reduced to the desired 
 shade with gum Senegal water. 
 No. 58. Another Buff.— 
 
 Water 5 gals. 
 
 Copperas 24 lbs. 
 
 Acetate of lead (brown) 10 „ 
 
 No. 59. Buff {Yellower Tone). — 
 
 Water 5 gals. 
 
 Copperas 10 lbs. 
 
 Acetate of lead 12 ,, 
 
 Acetic acid 1 quart 
 
 No. 60. Chrome Standard (Sulphate). — 
 
 Water 6 gals. 
 
 Bichromate 24 lbs. 
 
 Dissolve with the aid of heat, and put in a large stoneware pan, and add 
 
 Sulphuric acid, at 170 Tw 6 j pints. 
 
 Cold water 3 gals. 
 
 Stir in by degrees — 
 
 Sugar 6 lbs. 
 
 When the violent reaction and frothing are at an end, boil down to 3 gals. 
 
■■B 
 
 574 DYEING AND CALICO PRINTING. 
 
 No. 61. Chrome Standard (Muriate or Chloride). — 
 
 Boiling water .. , 2 gals. 
 
 Bichromate 8 lbs. 
 
 When dissolved add — 
 
 Hydrochloric acid at 32 Tw if gals. 
 
 And by degrees — 
 
 Sugar 3i lbs. 
 
 No. 62. Chrome Standard (Arseniatc). — 
 
 Water 2 gals. 
 
 Bichrome 10 lbs. 
 
 Arsenious acid (white arsenic) 14 lbs. 
 
 Hydrochloric (muriatic) acid, at 32 Tw ij gals. 
 
 Heat till the bichrome is entirely reduced and the liquid is a pure green with- 
 out an olive cast. Sometimes a further amount of acid is required to produce 
 this result. When the reduction is accomplished the mixture is concentrated 
 to 95 Tw. The chrome standards require care in their preparation; if not 
 perfectly uniform and smooth they should be re-heated, and a little more acid 
 added, if needful. Gum tragacanth is the best thickening material. 
 For a variety of "covers," see Style III., Reserves. 
 
 No. 63. Fast Blue Standard. — 
 
 Water 100 gals. 
 
 Indigo (wet-ground) 12 lbs. 
 
 Copperas 16 ,, 
 
 Lime, slaked 18J ,, 
 
 The whole is let stand for two days, and stirred from time to time; then 
 allowed to settle, and the clear liquor syphoned off is mixed with 1 pint double 
 muriate of tin, at 120 Tw., to every 10 gals. It is then thrown upon a flannel 
 strainer, and allowed to drain till it takes the consistence of a thick paste. 
 
 No. 64. Fast Blue (Machine). — 
 
 No. 63 1 quart. 
 
 Tin crystals 6 ozs. 
 
 Water 3 quarts. 
 
 No. 65. Fast Blue Standard. — 
 
 Indigo, ground wet 8 lbs. 
 
 Caustic soda, at 70 Tw 1 J gals. 
 
 Water 1} „ 
 
 Feathered tin, an excess. 
 Boil in an iron pan until a few drops, when placed on a pane of glass, appear 
 perfectly yellow. 
 
 No. 66. Fast Blue (Block).— 
 
 No. 65 1 quart. 
 
 Tin crystals 12 ozs. 
 
 Lime-juice, at 60° F 12 ,, 
 
 Gum Senegal water, at 6 lbs. per gal 3 quarts. 
 
MADDER STYLES. 575 
 
 No. 67. Fast Green. — 
 
 No. 65 i^ quarts. 
 
 " Lead gum " (see below) 2 „ 
 
 Tin crystals 8 02s. 
 
 No. 68. Lead Gum. — 
 
 Sugar of lead, white 8 lbs. 
 
 Nitrate of lead 4 „ 
 
 Hot water 1 g a l. 
 
 Gum Senegal water, at 6 lbs. per gal 1 „ 
 
 No. 69. Drab. — 
 
 No. 60 5 quarts. 
 
 Gumltragacanth water, at J lb. per gal 10 „ 
 
 Cochineal liquor, at 4° Tw 11 pints. 
 
 Bark liquor, at 8° Tw i£ M 
 
 No. 70. Fawn. — 
 
 No. 60 1 gal. 
 
 Gum tragacanth water, at £ lb. per gal 2 gals. 
 
 No. 8 j gal. 
 
 No. 71. Slate. — 
 
 No. 60 1 g a l. 
 
 Gum tragacanth water, at £ lb. per gal 1 ,, 
 
 Before these mordants, technically called colours, are printed on to the 
 calico it requires to be^bleached in the most thorough and complete manner 
 (see p. 44). After printing the goods are transferred to the ageing room, see 
 p. 280. The next process is the so-called dunging, effected either with actual 
 cow-dung, with the dung-substitutes, or with a combination of both. For a 
 detailed description of this process the reader is referred to p. 294. Next 
 follows the dyeing (garangage), see p. 299. Finally comes the clearing or 
 brightening (avivage), see p. 312. 
 
 The Plate Style, another modification of madder work, requires a some- 
 what modified procedure. For a plate purple, containing black and purple 
 only, one shade or more of the latter, print on No. 61 a purple, say No. 30, 
 regulated according to shade, and an acid, No. 50, and pad or cover in the 
 whole in a pale purple, No. 33. The goods are then aged, fly-dunged at 
 170 F., and dunged again for half an hour at 165 F. They are next washed 
 and dyed with ground Levant madder, to which have been added 5 per cent 
 of its weight of chalk and 3 quarts of bone-size. The temperature is raised in 
 two hours to 175 F., at which it is kept for half an hour. They are then well 
 washed and soaped, using 5 lbs. of soap for fifteen pieces, each 30 yards by 
 |ths, and boiling for half an hour. It is then again well washed, and passed for 
 five minutes through 300 gallons of water, at 140° F., to which have been added 
 2 quarts of solution of bleaching lime, at 8° Tw. They are again rinsed, and boiled 
 for half an hour with 3 lbs. of soap per fifteen pieces. Next wash, and repeat 
 the chloride of lime treatment for five minutes, using 200 gallons of water, 
 4 quarts solution of chloride of lime, at 8° Tw., and 2 lbs. carbonate of soda, 
 at 160 F. Wash again well and dry. 
 
 Plate Pinks are composed of shades of red and pink only. The process is 
 as follows : — Print on No. 34 dark red, with paler reds, as No. 36, and acid 
 
57 6 
 
 DYEING AND CALICO PRINTING. 
 
 No. 49. A very pale red mixture is padded all over. The goods are then 
 aged for two or three days and dunged at 160° F., taking care not to use any 
 dung substitute containing free alkali. Dye with the best French or Levant 
 madder. The shades produced are dyed purposely too full, from 4 to 6 lbs. of 
 Avignon madder being required per piece of J cloth. If the water is soft, chalk 
 may be added to the extent of about 5 per cent of the weight of madder. 
 The dye-beck is steadily raised to 150 F. in two hours, and kept for half an 
 hour at that heat. The pieces when dyed are firstly well washed and soaped 
 at 140 F. for half an hour with £ lb. soap per piece. Next they are well washed 
 in water and placed in another beck of cold water, slightly acidified with 
 sulphuric acid or perchloride (oxychloride) of tin. The heat is gradually 
 raised to 120 F. in about thirty minutes. When the goods show a bright 
 orange colour they are lifted and winced in water. This process, the reduction 
 of the reds and pinks to the depth of shade they are to have when finished, is 
 called "cutting." The more this acid treatment is prolonged, and the higher 
 
 
 
 Madder Red and Pink. 
 
 the temperature, the paler the pinks become. The pieces are then put in a 
 fresh beck and boiled with soap for an hour, lifted, washed again in pure 
 water, and boiled with soap and water at the pressure of 2 atmospheres for 
 two or three hours. The goods are next lifted, washed, and entered in a fresh 
 beck of water at 160 F., to which a very little bleaching soda (hypochlorite) 
 has been added. After ten minutes in this solution they are washed and 
 dried. 
 
 The above specimen will serve as an illustration of the madder style. 
 
 To produce this pattern, red liquor at 12 Tw., thickened with flour, is 
 printed in for the red, and a much weaker red liquor, similarly thickened, for 
 the pink. The pieces are then dunged, washed, dyed with madder, cleared, 
 and finished. (See p. 299). 
 
 The above is the first of a series of three patterns, for which we are 
 indebted to the kindness of Messrs. Wood and Wright, of Manchester. 
 
MADDER STYLES, 
 
 577 
 
 Madder Style. (First Stage.) 
 These serve to illustrate the successive stages of madder-work. In the first, 
 the mordants, or, as they are technically called " colours," — suitable for 
 subsequently producing, in combination with the tinctorial principles of the dye- 
 ware, black, purple, red, and light brown designs upon a white ground, — have 
 been printed on, and the pieces have been cleared and dunged (see p. .297, &c), 
 in order to remove the thickeners and saturate any mordant attached to the 
 fibre and not yet perfectly decomposed. After this process the goods are 
 ready to be dyed up in the madder-beck (see p. 299). The pattern below 
 shows their condition after dyeing and a subsequent washing, but before the 
 final clearing process. The shades are developed, but they are still deficient 
 in brightness, and the ground, which is intended to be white, is stained a dull 
 light red. The third, and last of the series (see next page), shows the appearance 
 of the pieces after having undergone the clearing process. The general 
 
 Madder Style. (After Dyeing.) 
 
578 
 
 DYEING AND CALICO PRINTING. 
 
 details of this operation are described in p. 309. The exact procedure fol- 
 lowed in this case is as follows : — After washing out of the dye-beck, the pieces 
 are next hot-watered, and then soaped at 140 F. for forty minutes. They are 
 next washed and soaped again, in fresh baths, for the same period of time, but 
 the temperature is increased to 160 F. They are again washed in plain 
 water, in order to remove traces of soap, which would interfere with the next 
 process. They are then cleared with a very dilute solution of chloride of 
 lime, washed again in clear water, and finished. The ground is now white, 
 and the colours of the design have lost in depth — for which an allowance was 
 made in the original intensity of the shade — and gained in brightness. 
 
 The first pattern on page 579 illustrates a different style of madder-work com- 
 bined with aniline black. To produce this effect the pieces are printed first with 
 so-called "acid," — i.e., lime-juice, — at 8° Tw., thickened with gum-substitute 
 (see Style I., No. 48, p. 572, and p. 318), to produce the white figure. Where 
 this mixture is applied, the mordants, which follow next, are prevented from 
 
 Madder Style. (After Clearing). 
 attaching themselves to the fibre; and when the pieces ultimately come out 
 of the dye-beck, this figure is found, not dyed, but merely stained with a faint 
 red, which is entirely removed in the clearing process, leaving a white, as 
 shown in the pattern. The black design is next produced with aniline (see 
 Aniline Black, p. 211), and remains unaffected during the subsequent opera- 
 tions. The pieces are then " covered " with iron liquor (see Nos. 30, 31, &c.) 
 to produce the small design in dark purple, and padded all over in a weaker 
 iron liquor (see No. 33) to give the light purple ground. The goods are then 
 aged for thirty-six hours, or longer, at 8o c F., dunged, washed, dyed in the 
 nadder-beck, — which produces the two shades of purple according to the 
 jth of the mordants, — and cleared. 
 In some printing establishments on the Continent, hydrofluosilicic acid is 
 amployed instead of citric acid. 
 
GARANCIN COLOURS. 
 
 579 
 
 Madder and Aniline Black. 
 Second Style. — Garancin Colours, 
 As a general rule the effects produced with crude madder can also be 
 obtained by the use of garancin (see p. 257). The shades, both dyed and 
 printed, with this preparation are fully equal to madder-colours — properly so- 
 called — in brilliance, but fall short of them in permanence and in power of 
 resisting the action of soapj light, air. &c. They are, nevertheless, commonly 
 classed amongst " fast colours," and are far more permanent than the shades 
 obtained with the woods. The best qualities of garancin yield colours which 
 will stand soaping to some extent, and which have this advantage over 
 madder, that they scarcely stain the white unmordanted grounds, and conse- 
 quently the operation of clearing (avivage) is much less severe. 
 
 ^ iMiHiMUMii ^ i ^iiiiitiiitttiiiwiwmmmHMii'inuu'iUUWlW 
 
 Garancin. 
 
Wtik I SB B Bfl l HHflHHH 
 
 BMfflWKa 
 
 BBS 
 
 IBM IWBBWi 
 
 Bfi 
 
 f 
 
 580 DYEING AND CALICO PRINTING. 
 
 Garancin is generally employed for full, heavy patterns, and especially for 
 combinations of black, red, and chocolate; for browns and drabs; black and 
 scarlet ; orange and brown, &c. The reason why garancin is selected in pre- 
 ference for heavy shades is that garancin gives up, practically speaking, the 
 whole of its colouring matter to the water in the dye-beck, whilst crude 
 madder yields only a part. Hence the employment of crude madder for heavy 
 shades is costly, as a large excess must be used, which is in great part wasted, 
 if the dregs are not subsequently converted into garanceux. The mordants 
 ("colours," technically called) for garancin work are used weaker than those 
 required for producing similar shades with madder. From two-thirds to three- 
 fourths of the strength used for madder is sufficient. For further particulars 
 relative to garancin dyeing the reader is referred to pp. 308, 496, and 497. 
 
 Garancin is very frequently associated with catechu for the production of 
 browns and brownish-reds. This combination may be brought about in various 
 ways. The second pattern on the previous page is given as a specimen of 
 the class of effects produced by this style. The mordants printed on for this 
 specimen are iron liquor, at io° Tw., for the blacks; and for the browns, 
 mixtures of catechu dissolved in water, with sal-ammoniac, acetic acid, and 
 a salt of copper, the latter being added along with the thickening. The pieces 
 are then dyed in the garancin-beck and cleared. 
 
 Third Style.— Reserved. 
 
 This style is an addition to the madder and the garancin styles. In goods 
 printed in these styles portions of the design are often left white, and these 
 spaces are afterwards filled in with a variety of colours, such as green, yellow, 
 or blue, produced and fixed by the steaming process, as described below. 
 
 There is also another method of combining madder, and garancin work with 
 steam-colours. There is blocked on the dyed piece a reserve paste, such as 
 either of the following : — 
 No. 1. Reserve. — 
 
 Lime-juice, at 50 Tw. 3 J gals. 
 
 Caustic soda, at 70° Tw i\ ,, 
 
 Raise to a boil, and work up in a separate vessel — 
 
 Pipe-clay 56 lbs. 
 
 Boiling water 33 gals. 
 
 And add — 
 
 Gum Senegal water (at 6 lbs. per gallon). 
 Mix the two liquids, and boil for twenty minutes. 
 
 No. 2. Reserve. — 
 
 Lime-juice, at 6o° Tw. 4 gals. 
 
 Caustic soda, at 70 Tw 3d 
 
 Boil and add — 
 
 Pipe-clay 48 lbs. 
 
 Beat up with — 
 
 Boiling water 2 quarts. 
 
 Gum Senegal water (at 6 lbs. per gallon) 4 gals. 
 
 Boil the whole for twenty minutes. 
 
 No. 1 is used to preserve reds and blacks. No. 2 is used where purples also 
 occur. 
 
"RESERVED" STYLE. 581 
 
 When the reserve paste is dry small patterns are covered in with the 
 machine with certain drabs, olives, &c. These are then dunged, and dyed 
 with quercitron, cochineal, madder and quercitron, &c. Where the reserve 
 has been applied, the original shade — or white spaces — will remain untouched 
 by the subsequent or covering-colour. Where white designs have been 
 reserved, steam-colours may now be blocked in. Among the covering shades 
 are — 
 
 No. 3. 5 Drab. — 
 
 Iron liquor, at 24 Tw 1 gal. 
 
 Water 5 gals. 
 
 British gum, light 9 lbs. 
 
 No. 4. 10 Drab. — The same, with double the amount of water and 18 lbs. 
 gum. 
 
 No. 5. Drab. — 
 
 Iron liquor, at 24° Tw. 1 gal. 
 
 Red liquor, at 20 Tw. 1 ,, 
 
 Water 5 gals. 
 
 British gum, light 10 lbs. 
 
 No. 6. Drab. — The same, with 10 gals, water and 20 lbs. gum. 
 No. 7. Olive. — 
 
 Red liquor, at 12 Tw 2 gals. 
 
 Iron liquor, at 14 Tw 1 gal. 
 
 British gum, light 6 lbs. 
 
 No. 8. Olive.— 
 
 Red liquor, at 18 Tw 3 gals. 
 
 Iron liquor, at 8° Tw 2 ,, 
 
 British gum, light 10 lbs. 
 
 No. 9. Sage. — 
 
 Red liquor, at 9 Tw 9 gals. 
 
 Iron liquor, at 12 Tw 1 gal. 
 
 British gum, light 16 lbs. 
 
 No. 10. Sage. — 
 
 Red liquor, at 3 Tw 14 quarts 
 
 Iron liquor, at 12° Tw 1 pint 
 
 British gum, light 5$ lbs. 
 
 No. 11. Chocolate. — 
 
 Red liquor, at 15 Tw 6 gals. 
 
 Iron liquor, at 24° Tw 1 gal. 
 
 British gum, light 10J lbs. 
 
 Flour 3£ ,, 
 
 Fourth Style.— Padding. 
 
 In the padding style the white calico is saturated all over, by means of the 
 padding process, with a mordant, generally red or black liquor, or a mixture of 
 both. It is next dyed in a specially arranged apparatus, known as a padding- 
 flue. The design to be finally produced is then printed on in an acid, to 
 
5^ 
 
 DYEING AND CALICO PRINTING. 
 
 remove the mordant, and the pieces are dunged and dyed. The pattern then 
 appears in white on a colour d ground. The so-called padding-flue is repre- 
 sented in Fig. 36. It is a long vaulted chamber, generally 35 yards in length 
 by 5 in width and 4 in height. At about half its length it is divided in two by 
 six arches, built transversely, which serve to preserve the main arch from the 
 action of the heat, and hinder the pieces, when dry, from being exposed to the 
 action of the moisture and acic!:i disengaged, c c is the furnace, whose flue 
 forms the bottom of the vault, covered with plates of cast-iron capable of 
 being heated neatly to redness. F is an arched passage communicating with 
 the interior of the stove, h h are ventilators in the side wall, which can be 
 opened or shut at will by the rod j. k k are cast-iron supports for copper 
 rollers, fastened to the pieces y y, and serving to conduct the calico. / / ;ire 
 bars supporting the fans, mm, covered with gratings, and revolving 300 times 
 in a minute. 
 
 Before the drying-flue stands the padding apparatus. Its trough being 
 charged with the iron liquor, or red liquor, as required, the pieces of calico are 
 conducted twice through it, and then into the flue. Their course is indicated 
 
 Fig. 36. 
 
 -*— , , , , 
 
 in the diagram by arrows. They are next printed with the acid mixture, aged 
 for two or three days, dunged and dyed. The following are some of the 
 colours commonly produced in this style : — 
 
 No. 1. Claret and White. — Pad in red liquor, at io° Tw. Dry, cool, pad 
 again in same liquor, dry, cool, and print with the following mixture ; — 
 
 Lime-juice, at 28 Tw. .. 1 gal. 
 
 Bisulphate of potash lib. 
 
 Strain, and thicken the clear liquor with — 
 
 Starch 1 lb. 
 
 After "printing, the goods are aged three nights. They are next fly-dunged at 
 a boiling heat, washed, dunged again at 160° F. for thirty minutes, washed, 
 dried and singed, washed, and dyed. For 12 pieces, 30 yards in length, there 
 are required— 
 
PADDING. 583 
 
 Ground peach-wood 18 lbs. 
 
 French madder 21 „ 
 
 Sumac 5 ,, 
 
 Logwood (aged) 5 „ 
 
 The pieces are run in the dye-beck cold for twenty minutes, and brought gra- 
 dually to a boil in seventy minutes, kept at this heat for fifteen minutes, run 
 out rinsed and washed ; next branned for ten minutes, at the boiling-point, 
 wu.i a few pounds of bran ; rinsed and branned again, washed, and dried. 
 
 No. 2. Scarlet and White. — Pad and dung as No. 1. For dyeing, take to 
 10 pieces — 
 
 French madder 15 lbs. 
 
 Dutch crop madder 15 „ 
 
 Peach-wood 7 ,, 
 
 Sumac 4 ,, 
 
 Bone size 3 quarts. 
 
 Bring to a boil in two and a quarter hours, and boil fifteen minutes. Wash 
 and bran as in No. 1. 
 
 No. 3. Scarlet and Yellow. — The general procedure as in No. 2. The dye- 
 materials are, for ten pieces, — ■ 
 
 French madder 22.J lbs. 
 
 Dutch crop madder 22£ ,, 
 
 Sumac 7.J ,, 
 
 After dyeing, the pieces are washed, branned, and dried ; then padded in red 
 liquor, at 16° Tw. ; aged for two nights, fly-dunged at 130° F., washed in warm 
 water at 120° F. ; then re-dyed in 20 lbs. quercitron bark per 10 pieces, raising 
 the heat to 120 F. in one hour, keeping at that temperature for fifteen 
 minutes ; then washing and drying. 
 
 No. 4. Burgundy and White. — Pad, &c, as .1 No. 1. For dyeing 10 pieces 
 take — 
 
 French madder 18 lbs. 
 
 Peach-wood 18 ,, 
 
 Logwood j| ,, 
 
 Sumac 5 ti 
 
 Glue 4 quarts. . 
 
 Raise to a boil i 1 one and three-quarter hours ; keep up the boil for fifteen 
 minutes; wash and bran for ten minutes at a boil, wash, and dry. 
 
 No. 5. Tyrian Purple and White. — Pad and prepare as in No. 1. For 
 
 dyeing, to 10 pieces, take — 
 
 Logwood 5 lbs. 
 
 Dutch madder (crop) 5 ,, 
 
 Peach-wood 7 »i 
 
 Bran 2 ,, 
 
 Bone size 3 quarts. 
 
 Raise to 212° F. in one and three-quarter hours ; keep at that heat for fifteen 
 
 minutes. Wash and bran for five minutes at 150° F., using 1 lb. bran per 
 
 piece; wash, and dry. 
 

 s 
 
 584 DYEING AND CALICO PRINTING. 
 
 No. 6. Puce and White. — The pieces are padded, &c., as in No. 1. For 
 dyeing, per 12 pieces, take — 
 
 Cochineal, finely ground 3 lbs. 
 
 Gall-nuts 1 lb. 
 
 Logwood 4 lbs. 
 
 Peach-wood 3 ,, 
 
 Raise to 170° F. in one hour and twenty minutes, and keep for ten minutes at 
 that heat. Wash, and bran for ten minutes at 160 F. ; then wash and dry. 
 No. 7. Amber and White. — Pad as in No. 1. For dyeing 10 pieces take — 
 
 Quercitron bark 20 lbs. 
 
 Dutch madder (crop) 10 ,, 
 
 Bone size 2 quarts. 
 
 Raise temperature to t6o° F. in seventy-five minutes, and maintain that heat 
 for fifteen minutes. Then wash, and bran at 150 F. for ten minutes. Wash 
 and dry. 
 
 No. 8. Peach and White. — Pad, &c, as in No. 1. For 10 pieces take — 
 
 Cochineal, ground 2 lbs. 
 
 Peach-wood 2 ,, 
 
 Logwood 6 ozs. 
 
 Raise to 140 F. in one and a quarter hours ; wash and bran at same tem- 
 perature for ten minutes ; wash and dry. 
 
 No. 9. Black and White. — Pad once in red liquor at 20 Tw. ; print design 
 with the following discharge : — 
 
 Lime-juice, at 22 Tw 1 gal. 
 
 Bisulphate of potash 1 lb. 
 
 Strain, and thicken the clear liquor with — 
 
 Starch 1 lb. 
 
 After printing, age for three nights, fly-dung at 212 F. ; give a second 
 dunging, at 140° F., for twenty minutes. Wash, dry, singe ; wash again, and 
 dye with, per 10 pieces, — 
 
 Logwood 60 lbs. 
 
 Bone size 4 gals. 
 
 Carbonate of soda, crystals 6 ozs. 
 
 Raise to 212 F. in seventy minutes ; wash and dry. 
 
 No. 10. Olive, Drab, &c, and White. — For drabs, pad in iron liquor diluted 
 according to the shade, and dye in bark, or bark and logwood. For the 
 former, per 10 pieces, use — 
 
 Quercitron bark 25 lbs. 
 
 Bone size 3 quarts. 
 
 Raise the temperature to 190° F. in ninety minutes, and maintain that heat 
 for ten minutes. Wash, and bran for ten minutes at 160° F ; wash and dry. 
 For the mixture of bark and logwood, per 10 pieces : — 
 
 Quercitron bark 20 lbs. 
 
 Logwood 30 ozs. 
 
 Bone size 3 quarts. 
 
 The heat is regulated as in bark-dyeing. 
 
 For olives, pad in mixtures of red liquor and iron liquor. 
 The white, &c, patterns obtained by this style may be diversified by means 
 of steam-colours blocked in. 
 
INDIGO EFFECTS. 
 
 585 
 
 Fifth Style.— Indigo Effects. 
 
 The combinations of colour produced by this style are — (1). Blue and white. 
 (2). Blue and yellow, or orange. (3). Blue, two shades. (4). Blue, two 
 shades, and white. (5). Blue, two shades, white, yellow, or orange. (6). Dark 
 blue and green. (7). Blue, two shades, and yellow. 
 
 The first of these varieties is produced by printing upon the cloth certain 
 " reserves," and then dyeing in the vat to the shade required. The design 
 then appears in white upon a blue ground. 
 
 No. 1. Reserve for Block-work. — 
 
 Sulphate of copper 3 lbs. 
 
 Water 1 gal. 
 
 Pipe-clay 15 lbs. 
 
 Beat up with some of the solution, and mix gradually to a smooth paste ; 
 then add — 
 
 Gum Senegal water, thick 1 gal. 
 
 Nitrate of copper, at 8o° Tw 1 quart. 
 
 No. 2. Reserve (Machine). 
 
 Sulphate of copper 2J lbs. 
 
 Water 1 gal. 
 
 Flour 9 lbs. 
 
 Dark British gum 2 ,, 
 
 No. 3. Reserve (Machine). — 
 
 Sulphate of copper 5 lbs. 
 
 Sugar of lead, white 2 ,, 
 
 Water 2 gals. 
 
 Dissolve, draw off the clear, and thicken with — 
 
 Flour 3 lbs. 
 
 Pale British gum 2 ,, 
 
 Cool, and add to every 2 gallons — 
 
 Nitrate of copper, at 8o° Tw J pint. 
 
 No. 4. Reserve (Machine). — 
 
 Sulphate of copper 8 lbs. 
 
 Boiling water 2 gals. 
 
 Sugar of lead, white 4 lbs. 
 
 Dissolve, let settle, and decant the clear, and to ij gals, of this add — 
 
 Flour 4 lbs. 
 
 Pale British gum 2 ,, 
 
 Boil, and add — 
 
 Sulphate of zinc 2 lbs. 
 
 The following mixtures serve to resist lighter vat-blues : — 
 
 No. 5. Reserve, Mild, fur Block. — 
 
 British gum, dark 25 lbs. 
 
 Water 15 quarts. 
 
 Boil for ten minutes, and add — 
 
 Soft soap 74 lbs. 
 
MSBi ■■ 
 
 WWHff 
 
 586 DYEING AND CALICO PRINTING. 
 
 When thoroughly incorporated add — 
 
 Sulphate of zinc 20 lbs. 
 
 Stir well in, and add — 
 
 Pipe-clay 10 lbs. 
 
 Water 7. J quarts 
 
 Nitrate of copper, at 8o° Tw, . , . . 7^ gals. 
 
 Mix all thoroughly together. 
 
 No. 6. Reserve, Mild (Machine). — 
 
 British gum, dark 8 lbs. 
 
 Water 32 quarts 
 
 Boil, and add — 
 
 Soft soap . . - . , . 2 lbs. 
 
 When cool add — 
 
 Sulp' ite of zinc 6 lbs. 
 
 Boiling water \ gal. 
 
 Nitrate of copper, at 8o c Tw 1 quart. 
 
 After the reserve paste is printed on, the goods are hung in a somewhat damp 
 atmosphere for forty-eight hours, and then dyed blue in the vat. 
 
 For yellow or orange designs upon a blue ground the following pastes are 
 used as reserves : — 
 
 No. 7. Yellow. — 
 
 Sulphate of copper 20 lbs. 
 
 Water 2 gals. 
 
 Nitrate of lead 20 lbs. 
 
 Dissolve, and thicken with — 
 
 Flour 12 lbs. 
 
 Sulphate of lead, pulp 2 gals. 
 
 Boil all well together. 
 
 N.B. The sulphate of lead here mentioned is the sediment left on making 
 red liquor with sugar of lead and alum (or sulphate of alumina), after running 
 off the clear liquid. 
 
 No. 8. Orange. — A standard is made as follows: — 
 
 Sugar of lead, white 24 lbs. 
 
 Water 6 gals. 
 
 Add litharge 12 lbs. 
 
 Stir the litharge in gradually till it is perfectly white ; allow the sediment to 
 subside, and use the cl^ar liquid. This is used instead of the water directed 
 in No. 7. After dyeing in the vat, the pieces are passed through sulphuric 
 acid sours, then well washed, and passed for ten minutes through a solution 
 of bichromate, at ioo° F., containing 2 ozs. of this salt per gallon. The 
 pieces are next well washed in water, and then winced in water and muriatic 
 acid, at J Tw., to which 1 oz. of oxalic acid per gallon has been added. This 
 treatment brightens the yellow design, and removes any trace of green that 
 may remain. The goods are then washed and dried. 
 
INDIGO EFFECTS. 
 
 587 
 
 In case of orange, the pieces after treatment in the oxalic-muriatic bath, 
 are washed and winced in the following mixture, at the temperature of 
 1S0 F. :— 
 
 Water 300 gals. 
 
 Bichromate 10 lbs. 
 
 Slaked lime, enough to make the liquid faintly milky. 
 
 When the orange pattern appears full and bright, the pieces are lifted, washed 
 thoroughly, and dried. 
 
 For two shades of blue : a pale blue — the lighter of the two shades — is first 
 given to the whole pieces in the vat. They are then taken out, well rinsed in 
 water, then passed through a sour (sulphuric acid at 2 Tw.) ; washed again, 
 squeezed, and dried. One of the reserves — Nos. 1, 2. 3, or 4 — is then printed 
 on, and the pieces are dipped again to the darker shade, and finished as for 
 white on a blue ground. The result is a pale blue design on a dark blue 
 ground. 
 
 For two shades of blue along with white, a design is printed in chloride of 
 manganese (muriate of manganese), thickened with British gum (dark), and 
 raised with soda and chloride of lime, as in the " Bronze " Style. The pieces 
 are thirn diied, and a further pattern blocked in with the reserve No. 1. They 
 are next limed, and dyed in the vat to the required shade, lifted, hung up to 
 oxidise, washed again, and winced in a sour of weak muriatic acid with the 
 addition of a little muriate of tin, washed again, and dried. The result is a 
 pale blue ground, showing a pattern in dark blue, where the indigo is super- 
 imposed upon a bottom of manganese-brown, and in white where the reserve 
 has been applied. 
 
 For two shades of blue, white, and yellow or orange, the process is begun 
 as in the case just described, only, in addition to reserve 1, No. 7 or 8 is also 
 blocked in. After passing the pieces through a sour of sulphuric acid, the 
 yellow or orange is raised with bichromate, as directed under " blue and 
 yellow." 
 
 For blue and green No. 7 is printed on, and the pieces are dyed a full blue. 
 They are then soured in dilute sulphuric acid, chromed, but not : jrwards 
 passed through the oxalo-muriatic beck. The yellow combining with the blue 
 will form a green. 
 
 For two shades of blue and one of green, the pieces are first dyed a light 
 blue. No. 5 or No. 6 is then printed on, and No. 8 to yield an orange. The 
 goods are then dyed, washed, soured, and chromed, and passed through very 
 dilute nitric acid. Where the white resists have been printed the sky-blue 
 remains, whilst No. 8 on the blue ground produces a green. The rest is dark 
 blue. If the nitric acid is too strong the indigo may be discharged. 
 
 Another indigo effect is the Lazulite or " neutral " style, at present little in 
 request. Mordants with reserves are printed in ; the pieces are then dipped 
 blue, when the printed portions repel the blue, and are dyed with madder. 
 Of this style there are two modifications : where mordants for red, chocolate, 
 or black, are printed along with a resist-white, and the pieces dyed a light 
 blue, the resist-white being in this case required to resist the blue only; and 
 secondly, where the white has to cut through the madder shades as well as 
 the indigo. Some of the colours for the former variety are here given: — 
 
9ERSB 
 
 588 DYEING AND CALICO PRINTING. 
 
 No. 9. Black (for Machine Work). — 
 
 Logwood liquor, at 12 Tw 1 gal. 
 
 Gall liquor, at 9 Tw 1 quart. 
 
 Red liquor, at 20" Tw 1 ,, 
 
 Iron liquor, at 24 Tw 1 ,, 
 
 Acetic acid , . 1 ; , 
 
 Flour 3 lbs. 
 
 Starch j lb. 
 
 Boil well together, and add — 
 
 Gallipoli 1 pint. 
 
 Turpentine 1 ,, 
 
 No. 10. Chocolate (for Machine). — 
 
 Red liquor, at 12° Tw i\ gals. 
 
 Iron liquor, at 24 Tw \ gal. 
 
 Sulphate of ccppper 3 lbs. 
 
 Nitrate of copper, at ioo° Tw 1 quart 8 ozs. 
 
 Flour 5 lbs. 
 
 British gum (dark) 1 lb. 
 
 No. 11. Chocolate (Block). — 
 
 Red liquor, at 12 Tw 2 J gals. 
 
 Iron liquor, at 24° Tw J gal. 
 
 Sulphate of copper 4i lbs. 
 
 Nitrate of copper, at ioo° Tw 3 pints 12 ozs. 
 
 Pipe-clay 18 lbs. 
 
 Work up the pipe-clay well, and add — 
 
 Gum Senegal water, at 5 lbs. per gal ij gals. 
 
 No. 12. Dark Resist-Red (for Block Work).— 
 
 Red liquor, at 22 Tw $ gal. 
 
 Sugar of lead, white 5! ozs. 
 
 Sulphate of copper 4$ » 
 
 Dissolve, and mix up in it — 
 
 Pipe-clay 6J lbs. 
 
 Meantime the following mixture is made separately : — 
 
 Red liquor, at 12 Tw 2 quarts. 
 
 Flour 12 ozs. 
 
 Heat, and when boiling add — 
 
 Soft soap, melted J lb. 
 
 When thoroughly dissolved add the former mixture, and next — 
 
 Red liquor, at 2° Tw J gal. 
 
 Thickened as required with gum Senegal. 
 
 No. 13. Dark Resist-Red (for Machine Work). — 
 
 Nitrate of zinc, at 36 Tw 5 gals. 
 
 Water, sightened with peachwood i\ ,, 
 
 Alum I2i lbs. 
 
 Acetate of lead 10 lbs. 
 
 Heat till dissolved, and keep stirring while cooling, when thicken with — 
 
 Flour 8 lbs. 
 
 British gum (dark) ij ,, 
 
INDIGO EFFECTS. 589 
 
 For lighter shades the alum and sugar of lead are proportionately reduced 
 (See also p. 474.) 
 
 No. 14. Brown Resist. — 
 
 Catechu 24 lbs. 
 
 Sal-ammoniac 6 ,, 
 
 Water 2 gals. 
 
 Acetic acid 1 gal. 
 
 Boil for a quarter of an hour, and add — 
 
 Gum water 74 gals. 
 
 Nitrate of copper, at ioo° Tw ij ,, 
 
 No. 15. White Resist. — 
 See Nos. 5 or 6. 
 The pieces after ageing for seventy-two hours, and dipping to the required 
 shade in a vat composed of — Indigo, 120 lbs. ; copperas, 135 lbs. ; and lime, 
 150 lbs. to 1000 gals, water, are washed, dunged for a quarter of an hour, at 
 160 F., washed again, and dyed up with madder or garancin. 
 
 In the other modification of the lazulite style the following whites are 
 used : — 
 
 No. 16. Lazulite White (Block). — 
 
 Lime-juice, at 30 Tw 3 J gals. 
 
 Water £ gal. 
 
 Sulphate of copper g lbs. 
 
 Pipe-clay 48 lbs. 
 
 Lime-juice, at 30 Tw if gals. 
 
 Separately thickened with gum Senegal before adding it to the rest. (See 
 also p. 474.) 
 
 No. 17. Ditto for Machine. — 
 
 Lime-juice, at 42 Tw 2 gals. 
 
 Sulphate of copper 4 lbs. 
 
 Nitrate of copper, at ioo° Tw 3 pints 4 ozs. 
 
 Previously thickened with starch i| lbs. 
 
 For blacks, see Style I., Nos. 6 and 7. 
 In this style the lazulite or neutral whites are first printed in, and 
 when perfectly dry the other reserve colours are printed over them. If a white 
 under the blue alone is wanted, Nos. 5 and 6 (of this style) may also be 
 printed. The pieces are then aged, dyed blue, washed, dunged, dyed with 
 madder or garancin, soaped, and washed. The effedt may then be further 
 diversified by blocking in steam, spirit, or pigment colours. 
 
 It must be remarked that indigo, in whatever manner applied, though it 
 yields fast colours, is always dull, and never produces a pleasing effedt upon 
 calico. Its use is, therefore, ordinarily confined to the lower qualities of 
 printed goods. 
 
 The three following patterns are a combination of indigo with other colours. 
 In the first stage we see a dark vat blue, on which a lighter blue design has 
 been "reserved." 
 
 In the second stage a discharge has been printed on, so that the pattern 
 now shows a design both in light blue, and in white upon the original dark 
 blue ground. 
 
590 
 
 
 DYEING AND CALICO PRINTING. 
 
 Finally, other colours are produced upon the white portions. The red is 
 madder; the yellow portions are chromate of lead, which also produces the 
 green when applied upon the blue portions, and the orange when applied 
 upon the reds. These patterns have been printed at the establishment of 
 Messrs. Wood and Wright. 
 
 The following method of applying indigo, simultaneously with mordants 
 for madder and garancin, producing thus a variety of novel and striking 
 effedts, was invented and patented by Mr. J. Lightfoot (Specification No. 3668, 
 Dec. 26, 1867). The patentee prepares a pulp of indigotin and tin by any 
 of the following methods: — He takes dry indigo, ground and prepared, i£ lbs., 
 or if indigo-pulp is used such a quantity as may be equal to that weigl.t of 
 dry indigo; tin crystals, protochloride of tin, i£ lbs. ; caustic soda, at 30 Tw. 
 (or caustic potash, at 40 Tw.), 1 gal. These materials are put in the colour 
 pan, and raised to a boil in half an hour, when 1 gal. of boiling water is 
 added. The mixture is then allowed to become quite cold, and 3 gals, of cold 
 
 Indigo Style. (First Stage). 
 
 water are added, in which £ lb. sugar has been previously dissolved. To this, 
 solution he adds 2\ pints of muriatic acid, at 32 Tw., or i.pint of ordinary 
 sulphuric acid, previously diluted with 1 pint of water, and allowed to stand 
 till clear and cold; or 3 quarts of acetic acid at 8° Tw. The indigotin may 
 also be precipitated by a mixture of protochloride of tin solution (double 
 muriate), at 120 Tw., with any of the acids above named, taking \ pint of 
 of the tin solution to half the quantities of acids given above. Of all these 
 precipitants, acetic acid alone is preferable. The indigotin precipitate is 
 filtered through a deep conical filter, leaving as small a surface exposed to the 
 air as possible. The pulp from the above quantities, when filtered, should 
 
 measure about 1 gal. 
 
 To make a blue colour for printing the patentee takes 4 gals, of the above 
 
 indigo-precipitate and 14 lbs. gum Senegal in powder, stirring till dissolved ; 
 
 the colour when strained is ready for printing. 
 
• 
 
 INDIGO EFFECTS. 
 
 591 
 
 Indigo Style. (Second Stage). 
 
 For a green colour he takes 4^ gals, of indigotin precipitate ; 18 lbs. 
 powdered gum Senegal, stirring till dissolved; n lbs. of nitrate of lead and 
 11 lbs. white sugar of lead, both in powder, are then added ; the mixture is 
 stirred till all is dissolved and strained. 
 
 Compound colours are made by mixing the blue and green colours with 
 each other, or with the ordinary mordants for dyeing. With the blue and 
 green above described, and with the ordinary iron and alum mordants (as used 
 for madder and garancin work), the inventor prints calico, and after cooling, ages 
 the pieces for one night. They are then fixed by passing them into a solution 
 of silicate of soda at 8 D Tw., or silicate of potash, at 12 Tw., to which 1 oz. 
 powdered chalk is added per gal. ; or into a mixture of silicate of soda or silicate 
 of potash, at 8° Tw., with carbonate of potash at 12° Tw. This bath is heated 
 to go° F. in a cistern fitted with rollers at top and bottom. The pieces pass 
 
 Indigo Style, with other Colours. (Third Stage). 
 
592 
 
 DYEING AND CALICO PRINTING. 
 
 Style Produced by Lightfoot's Patent Process. 
 
 through this solution at the rate of 25 yards per minute. After this the 
 pieces are winced in a pit of cold water fitted with a reel about 4 feet above 
 the surface. By this process the indigotin attached to the fibre is rendered 
 blue. If the green mixture has been printed on the pieces are next passed 
 into a solution of bichrome containing 1 oz. of bichromate of potash per gal. of 
 water, at ioo° F. for five minutes, when the goods are washed. The pieces 
 are next submitted to " second dunging" for fifteen to twelve minutes, in a 
 beck containing cow-dung and water, at ioo° F. They are then washed in 
 water, and dyed with madder, munjeet, flower of madder, garancin, extract 
 of madder, cochineal, mixtures of garancin with sumac and bark. The 
 grounds are then cleared in the ordinary manner, preferably with chloride of 
 lime as applied to garancin colours. 
 
 The above and following patterns, which we owe to the courtesy of 
 Messrs. Grafton and Co., are produced by Lightfoot's patent process. 
 
 Style Produced by Lightfoot's Patent Process. 
 
INDIGO STYLES. 
 
 593 
 
 Sixth Style.— China (Indigo) Blues. 
 This style produces blue figures on a white ground, and is therefore 
 'the reverse of Style V. A mixture containing indigo is printed on, and 
 is then fixed by further treatment. The standard colour is made as 
 follows : — 
 
 No. i.— 
 
 Indigo 45 lbs. 
 
 Iron liquor, at 24 Tw. . . . . 9 gals. 
 
 Copperas 18 lbs. 
 
 The mixture is ground in an indigo mill for three days, or till perfectly smooth 
 and uniform, and is then further mixed with — 
 
 Gum Senegal water, at 6 lbs. per gal 7 J gals. 
 
 The whole is then ground together for an hour, and the mill is finally washed 
 out with 1 gal. or i£ gals, of hot water, and the washings added. To reduce 
 [this standard to the shade desired, the following mixture, technically called 
 "China blue gum,'''' is used. 
 I No. 2.— 
 
 Gum Senegal water, at 3 lbs. per gal 2 gals. 
 
 Copperas i lb. 
 
 I Other standards are occasionally employed for the same purpose, such as : — 
 i No. 3. Dark China Blue. — 
 
 Indigo 12 lbs. 
 
 Iron liquor, at 22° Tw 2j gals. 
 
 Copperas 12 lbs. 
 
 Orpiment 3 ,, 
 
 The first two ingredients are ground together for about three days, the 
 
 [•Others added, and the grinding continued for three days more. Gum water is 
 
 (then added to the extent of 3 gals., and the grinding is resumed until the 
 
 feolour is quite uniform. This standard is reduced to the shade required with 
 
 gum water. 
 
 | No. 4. Resist for China Blues. — 
 
 Sulphate of copper 4 lbs. 
 
 Acetate of lead 4 „ 
 
 Water 2 gals. 
 
 Flour 5 lbs. 
 
 1, and when almost cold add — 
 
 Nitrate of copper in crystals 10 lbs. 
 
 Lime-juice, at 36 Tw 2 quarts. 
 
 also p. 484). 
 fter the pieces have been printed and aged, the pieces are dipped alternately 
 lime-water and in a copperas vat, standing at i£° Tw. The time of each 
 ling varies from fifteen to forty-five minutes, according to the shade required, 
 the number of dippings in each vat may be as low as four and as high as 
 lit. They are next well rinsed in water, passed into sulphuric acid sours, 
 : strength of which may run as high as o, c or io° Tw., and left there till the 
 
 29. 
 
WM 
 
 '*-$'';-*, 
 
 ^y^'X 1 ^ 1 ')' 
 
 BIB 
 
 594 DYEING AND CALICO PRINTING. 
 
 whites are cleared. The pieces are then well washed, and next cleared in a 
 soap-beck, at 120 F., for fifteen minutes, using about 4 ozs. soap per piece. 
 After again washing they are passed into weak sulphuric sours, i°Tw., at ioo° 
 to no° F., washed again, and dried. 
 
 The prolonged dippings involve a great outlay of time and labour and 
 render the China blue style costly. A saving of expense is effected by 
 forming the dippings by machinery instead of by hand, but the quality of the 
 work is inferior. In addition this style does not admit of the highest degree 
 of sharpness and delicacy of design. 
 
 A process which admits of the execution of delicate patterns is the white 
 discharge style for indigo blues, invented by Mr. J. Mercer. The process is 
 begun by dyeing the pieces in a uniform blue in the vat, generally a medium 
 shade. They are next washed and padded with a solution of bichrome, at 
 6° T. They must now be dried in a current of cold air, and in the shade, 
 sunshine — or even strong indirect light — and an elevated temperature being 
 equally fatal to success. They are then printed with the following : — 
 
 No. 5. White Discharge. — 
 
 Water 1 gal. 
 
 Flour 2 lbs. 
 
 Dark British gum 2 „ 
 
 Boil up and mix thoroughly, and when nearly cool add — 
 
 Oxalic acid 2 lbs. 
 
 And when quite cold — 
 
 Sulphuric acid 7A ozs. (measure). 
 
 This mixture rapidly removes the vat blue, leaving only a whitish-grey. The 
 pieces are then nearly dried, and winced first in a mixture of ground chalk 
 and water, then in weak sulphuric acid sours, at 2° Tw., then in water. They 
 are next well washed and dried, when the discharged portions will be found of 
 a pure white. If the pieces have been exposed to sunlight after the chroming 
 process, or dried too sharply at an elevated temperature, the blues are 
 spoiled. 
 
 Indigo Greens, or Dipped Greens, are now in less request than formerly. 
 In producing them either white cloth, or cloth printed and dyed with madder 
 colours, is printed with No. 5 or 6 (Style V.) by block or machine as most 
 appropriate. The green dipping is next effected as follows : — The pieces pass 
 first through an ordinary light blue vat ; then after travelling some yards in 
 the air to secure oxidation, they enter a lead vat, composed cf 250 lbs. brown 
 sugar of lead and 130 lbs. of dry slaked lime, dissolved in 1000 gals, of water. 
 They then enter a third vat of water alone, and pass finally through a vat of 
 solution of bichrome, at 4° Tw., which brings up a yellow with the lead, and 
 thus converts the blue into a green. 
 
 Seventh Style. — Discharges on Turkey-Reds. 
 No. 1. White Discharge (Machine). — 
 
 Tartaric acid solution, at 62° Tw 1 gal. 
 
 Acetic acid, at 6° Tw 1 „ 
 
 British gum (light) 8 lbs. 
 
DISCHARGES ON TURKEY-REDS. 
 
 No. 2. White (Machine), — 
 
 Tartaric acid 6 lbs. 
 
 Water i gal. 
 
 Starch ij lbs. 
 
 No. 3. White (Block).— 
 
 Tartaric acid 9 lbs. 
 
 Hot water 1 gal. 
 
 Pipe-clay 10 lbs. 
 
 Gum Senegal water 3 quarts. 
 
 No. 4. White (Block).— 
 
 Tartaric acid 10 lbs. 
 
 China clay 7J „ 
 
 Bichloride of tin i£ 
 
 Gum water 1 pint. 
 
 Water 1 gal. 
 
 No. 4<r. White. — 
 
 Water 2 gals. 
 
 Tartaric acid 15 lbs. 
 
 Dissolve at a boil, and beat up with — 
 
 Pipe-clay 9 lbs. 
 
 And add — 
 
 Gum water \ gat. 
 
 Containing 2 lbs. gum. 
 
 No. 46. White.— 
 
 Water 3 quarts. 
 
 White starch 3 lbs. 
 
 Boil well together, and add — 
 
 Tartaric acid 5 lbs. 
 
 Oxalic acid £ lb. 
 
 No. 5. Black Discharge. — 
 
 Logwood liquor, at 4 Tw 1 gal. 
 
 Yellow prussiate 2 lbs. 
 
 Gum-tragacanth water (thick) 1 quart. 
 
 Flour 2 lbs. 
 
 Boil and add — 
 
 Iron liquor, at 30° Tw 2 quarts. 
 
 When cool add — 
 
 Nitrate of iron, at 8o° Tw 1 gill. 
 
 No. 5 a. Black Discharge. — 
 
 Water 1 1 quarts. 
 
 Pyrolignite of iron, at 20 B ij „ 
 
 White starch 3 J 02s. 
 
 Boil well together, and add — 
 
 Bleu de Paris, dry 12 ozs. 
 
 Previously stirred up with hydrochloric acid. 
 
 595 
 
 2 Q2 
 
m») 
 
 rWWWTWT 
 
 HI 
 
 I 
 
 596 DYEING AND CALICO PRINTING. 
 
 No. 6. Blue-black Discharge.— 
 
 Logwood liquor, at 8° Tw 3 gals. 
 
 Gall liquor, at 9' Tw , . , 7 „ 
 
 Starch 20 lbs. 
 
 Boil and add whilst still hot — 
 
 Yellow prussiate 2j lbs. 
 
 When cold add — 
 
 Muriate of iron, at 6o° Tw 3 quarts. 
 
 Nitrate of iron, at 80° Tw 3 „ 
 
 No. 7. Black. — 
 
 Logwood liquor, at 8° Tw 7 gals. 
 
 Pyroligneous acid 1 gal. 
 
 Starch 10 lbs. 
 
 Boil and add — 
 
 Copperas 2 lbs. 10 ozs. 
 
 Boil again, cool, and add — 
 
 Nitrate of iron, at 8o° .. 3J pints. 
 
 Blue paste (see below) 1 gal. 
 
 No. 8. Blue Paste.— 
 
 a. Copperas 6 lbs. 
 
 Water .. . . • 2 qts. Dissolve. 
 
 b. Prussiate of potash 4 lbs. 
 
 Water 1 gal. 
 
 Mix a and b together, and add — 
 
 Standard red liquor 1 quart. 
 
 Nitric acid., at 6o° Tw 1 quart. 
 
 No. 9. Blue Discharge [Machine). — 
 
 a. Prussian blue lib. 
 
 Oxalic acid 1 ,, 
 
 Hot water 1 quart. 
 
 Grind finely up together, and allow to stand for twenty-four hours. 
 
 b. Water 3 quarts. 
 
 Starch ij lbs. 
 
 Boil and add — 
 
 Tartaric acid 2 lbs. 
 
 Mix a and b together. 
 
 No. 10. Blut Discharge. — 
 
 Tartaric acid 5 lbs. 
 
 Water 1 gal. 
 
 Tin pulp 1 ,, 
 
 Double muriate, at 120° Tw 2 gals. 
 
 Gum tragacanth water 2 ,, 
 
 No. 11. Blue Discharge. — 
 
 Oxalic acid 8 ozs. 
 
 Tartaric acid 4! lbs. 
 
 Yellow prussiate 2 „ 
 
 Copperas 2 ozs. 
 
 Starch 1 lb. 
 
 Gum tragacanth 2 ozs. 
 
 Water 3 quarts. 
 
DISCHARGES ON TURKEY-REDS. 597 
 
 No. 11 a. Bine. — 
 
 Water 1 gal. 
 
 Tragacanth mucilage 1 ,, 
 
 Citric acid 3 lbs. 
 
 Tartaric acid 2? ,, 
 
 Oxalic acid I J „ 
 
 Boil well together, and add to the mixture when cold — 
 
 Prussian blue paste, in bichloride of tin 1 lb. 11 ozs. 
 
 No. 12. Yellow Discharge (Block). — 
 
 Lime-juice, at 50 Tw 1 qral. 
 
 Tartaric acid 4 lbs. 
 
 Nitrate of lead 4 ,, 
 
 When dissolved add — 
 
 China clay 6 lbs. 
 
 Gum Senegal 3 ,, 
 
 No. 13. Yellow Discharge (Machine). — As No. 12, but instead of China 
 clay and gum thicken with i£ lbs. starch. 
 
 No. 14. Yellow Discharge (Machine). — 
 
 Lime juice, at 40 Tw 1 gal. 
 
 Tartaric acid 4J lbs. 
 
 White sugar of lead 5 „ 
 
 Starch ii „ 
 
 Boil, and add when cool — 
 
 Nitric acid, at 6o° Tw 1 lb. 14 ozs. 
 
 No. 15. Yellow (Machine). — 
 
 Water 2 gals. 
 
 Starch 3 lbs. 
 
 Boil, and add — 
 
 Nitrate of lead 5 lhs - 
 
 Tartaric acid 15 ,, 
 
 No. 16. Yellow (Machine). — 
 
 Lime-juice, at i8 u Tw 2 gals. 
 
 Nitrate of lead 8 lbs. 
 
 Tartaric acid 5 ,, 
 
 Gum substitute 6 ,, 
 
 No. 16 a. Yellow. — 
 
 Pipe-clay 10 lbs. 
 
 Light brown starch 3 ,, 
 
 Water $ gal. 
 
 Boil up and incorporate thoroughly ; then add — 
 
 Tartaric acid 8 lbs. 
 
 Citric acid 2 ,, 
 
 When cold add — 
 
 Gum water ^ gal. 
 
 Nitrate of lead 8 lbs. 
 
 Dissolved in — 
 
 Boiling water 3 quarts. 
 
598 DYEING AND CALICO PRINTING. 
 
 No. 16 b. Yellow. — 
 
 Tragacanth mucilage ij gal. 
 
 (3 gals, water to 2 lbs. gum tragacanth.) 
 
 White starch 6 lbs. 
 
 Water § gal. 
 
 Boil we'll together, and add — 
 
 Tartaric acid 6 lbs. 
 
 Citric acid 5 ,, 
 
 Nitrate of lead 10 „ 
 
 Instead of tartaric and citric acid, hydrofluosilicic acid may be used, which is 
 much cheaper. 
 
 No. 17. Green Discharge {Machine). — 
 
 Blue, No. 9 1 J gals. 
 
 Yellow, No. 14 igal, 
 
 Any of these discharges, as may be required, is printed in, and when dry 
 the pieces are run through the " decolouring vat" which is composed as 
 follows : — 
 
 No. ij a. Green Discharge. — 
 
 No. 16 b. Yellow 3 gals, ij qts. 
 
 Mix up well with — 
 
 Bleu de Paris, in paste 2\ to 3£ lbs. 
 
 No. 18.— 
 
 Water 1000 gals. 
 
 Chloride of lime 1000 lbs. 
 
 Stir well, till quite free from lumps and coarse fragments. A frame, with 
 wooden rollers at top and bottom, is then set in the liquid, which is kept con- 
 stantly stirred up, so as to be perfectly homogeneous. The pieces are then 
 run through the liquid at the rate of one (28 yards) in three minutes. After 
 passing through the squeezing-rollers they are passed into water and rinsed, 
 and then winced for ten minutes in solution of bichrome, at 4° Tw. They are 
 next washed in pure water, and again in water soured with muriatic acid ; 
 washed again, and dried. Except where the discharges have been printed on, 
 the Turkey red is not perceptibly affected, but in those places it is discharged 
 the design either remains white, or a mineral colour — blue, yellow, green, &c. 
 — is left in place of the red. 
 
 Eighth Style.- Steam Colours. 
 This style embraces those colours which are developed and fixed by steam. 
 The experiments which first led to the adoption of this process were made 
 with dry heat. As these attempts were unsatisfactory, steam was introduced, 
 though it was at first apprehended that the colours would run. Its action is 
 simply that of heat combined with moisture, both being regular and under 
 control. The modes of steaming vary greatly in different establishments. 
 In some works, before steaming, the pieces are exposed to the air, at common 
 temperatures, for a day and a night ; whilst in others the calico goes direct 
 from the machine to the steam-chest. The degree of moisture in the steam 
 varies also greatly, some practical men using it very dry, and others damp, 
 being of course guided by the quality of the goods, the nature of the colours 
 
STEAM COLOURS. 
 
 599 
 
 and thickening, and the effect to be produced. In some establishments the 
 steam is applied for a short time, when the goods are taken out, exposed to 
 the air, and steamed again. In others the goods are exposed to the action of 
 the steam for the required time without interval. The two principal con- 
 trivances for steaming are the " column " and the " chest," each of which has 
 its advocates. The column is a cylinder of copper, about 44 inches in length, 
 and varying in diameter from 3 to 5 inches, its surface pierced all over with 
 small apertures, - I 1 li th of an inch in diameter and set Jth of an inch apart. 
 Around this cylinder the goods are coiled, a copper plate, of about g inches in 
 diameter, being soldered to its bottom end, to prevent the cloth from slipping 
 off. At the lower end of the column is fixed a pipe, with a tap to regulate the 
 entrance of steam from a boiler. There are various arrangements for the 
 admission of the steam and for the exit of condensed water. The cylinder is 
 enfolded first in several layers of a woollen tissue, then in several folds of 
 white calico, and lastly in the printed goods. It is then enclosed in a wrapping 
 of white calico. The steaming is kept up for twenty to thirty minutes, 
 according to the nature of the dye. As soon as the steam is shut off the 
 pieces are unrolled, to prevent the running of the colours in consequence of 
 the condensation of steam. 
 
 The steam-chest, however, is the apparatus most generally employed in 
 this country. It is an iron chamber with a pent-house top, usually about 
 12 feet long, 6 wide, and 9 high at the top. At one end it is fitted with a 
 closely-made folding-door, secured with a cross bar, held in its place by screws. 
 The chest has a false bottom on a level with the floor of the room. Beneath 
 this runs a steam-pipe perforated with holes, and extending under three sides 
 of the chest. The steam escapes through the holes in this pipe, and is distri- 
 buted still more completely by means of the holes in the false bottom. Upon 
 this false bottom are placed two rails, parallel with the sides of the chest, and 
 extending beyond the chest into the room. The part of these rails nearest 
 the chest, for 3 feet, is fitted with hinges, so as to be movable on one side 
 when the door is opened or shut. An oblong frame of wood moves upon these 
 rails, fitting closely inside the chest, and standing as high as where the slope 
 of the roof begins. When this frame has been drawn out into the room it is 
 filled with pieces as follows : — They are wound one after another upon an 
 open reel, keeping the selvages of each fold parallel. Each piece is then 
 drawn off the end of the reel and flattened, when a thread is passed through 
 all the selvages of one side, and loops are made through which pass wooden 
 rods that are supported on the sides of the carriage. The pieces now .hang 
 with their selvages downwards, and the carriage, which is fitted with rods, 
 slides back into the steam-chest, when the doors are shut, and the steam 
 escapes by a safety-valve. After exposure for three-quarters of an hour the 
 pieces are taken out, unfolded, and again loosely folded, to be ready for rinsing 
 off. They are then stitched together, end to end, and passed through a cistern 
 containing water, and thence into another filled with a very dilute solution of 
 red chrome. They are next washed in the machine, transferred to the hydro- 
 extractor, starched, and dried. 
 
 This style of printing has a considerable resemblance to woollen and 
 worsted dyeing, since some of the mordants are applied simultaneously with 
 the extracts of dye-woods, or other colouring matter, both being, in fact, 
 
BBBB 
 
 6od DYEING AND CALICO PRINTING. 
 
 incorporated with each other. After this mixture has been printed on the 
 calico, the action of the steam, like that of boiling water in woollen-dyeing, 
 effects the combination between mordant, colour, and fibre. The finest effects 
 in this style are obtained by preparing the cloth first with a tin mordant, so as 
 to fix peroxide of tin in the fibre. In case of woollen and worsted goods, 
 indeed, this " preparing," as the operation is technically called, is absolutely 
 necessary for the production of good colours. The peroxide of tin thus depo- 
 sited in the fibre acts not only as a mordant, but it helps in neutralising the 
 acidity of many steam-colours, and aids thus in the formation of sub-salts — 
 or basic compounds — which combine most readily with colouring matters. 
 The methods of " preparing " in different print-works vary greatly, according 
 to the judgment of the proprietor, the kind of cloth operated upon, and the 
 effects intended to be produced. The article generally used is, however, the 
 stannate of soda, often known in the trade, in consequence, as " alkaline 
 preparing salts." 
 
 Calicoes are frequently prepared as follows : — The pieces, stitched together 
 by their ends, are padded, with a machine with wooden rollers, in a solution 
 of stannate, at io° Tw. This process is repeated twice, with the interval of 
 an hour, during which the pieces are allowed to remain wet. They are then 
 winced through diluted sulphuric acid, at i£° to 3 Tw. ; winced again in pure 
 water, and washed. The washing must be merely sufficient to remove free 
 sulphuric acid. After this operation the pieces are unstitched, freed from 
 excess of water in the hydro-extractor, and carefully dried at a steam-heat. 
 
 As a prepare for heavy shades the following procedure is in use : — The 
 pieces are padded in stannate, at 24 Tw. ; left wet for about two hours; 
 winced in dilute sulphuric acid (technically called "vitriol sours "), at 6° Tw. ; 
 washed and partially dried in the hydro-extractor. These operations are all 
 repeated once more, in the same order, and the pieces are then dried. The 
 acid liquid, of course, soon becomes reduced in strength, from the amount of 
 alkali neutralised — a point which requires constant attention, since, if the 
 " sours " be not kept up to the proper pitch, the tin deposited on the fibre will 
 wash off, and the work will be quite irregular. 
 
 Some printers use, along with the stannate of soda, arsenical compounds, 
 and also the tungstate of soda. See chapter on Mordants, pp. 534 and 542. 
 
 The following steam-colours are in common use : — 
 
 No. 1. Steam-Black, for Cylinder-work. — 
 
 Logwood extrait, at 12 Tw 1 gal. 
 
 Gall liquor, at 9 Tw . . 1 quart 
 
 Mordant (see below) 1 ,, 
 
 Flour 2 lbs. 
 
 Starch 6 ozs. 
 
 The whole is boiled for ten minutes, and mixed with J pint nitrate of iron. 
 
 The mordant above mentioned consists of — 
 
 Acetic acid 1 quart 
 
 Acetate of copper 1. J quarts 
 
 Iron liquor, at 24 Tw i| ,, 
 
 Red liquor, at 20 Tw. 1 quart. 
 
STEAM COLOURS. 601 
 
 No. 2. Another Black. 
 
 Logwood liquor, at 6° Tw i g a l. 
 
 Starch ri l bs# 
 
 Boil, and add whilst still hot — 
 
 Copperas 5 ozs> 
 
 Stir thoroughly, and when the mixture is almost cold add — 
 
 Gallipoli oil 2 ozs. 
 
 Nitrate of iron, " well killed " io , 
 
 No. 2 a . Black. — 
 
 Logwood liquor, at 12 Tw i g a i. 
 
 Gall liquor, at g° Tw i quart. 
 
 Red liquor, at 20 Tw ! 
 
 Iron liquor, at 24 Tw ! 
 
 Acetic acid 1 
 
 Thicken with — 
 
 Wheat flour 3 lb s# 
 
 Starch ^ lb. 
 
 Boil, and add — 
 
 Gallipoli oil , 1 pint 
 
 Oil of turpentine 1 ,, 
 
 This colour is useful either for steaming, raising through soda and washing off 
 
 in water, orfor a black to work with garancin or alizarin purple to go through 
 
 the dye-beck. 
 
 No. 3. Blue, for Cylinder, Dark. — 
 
 Water 7 ga i St 
 
 Starch i 4 lbs. 
 
 Sal-ammoniac 2| ,, 
 
 Boil these ingredients, and whilst hot add — 
 
 Yellow prussiate, ground 12 lbs. 
 
 Red prussiate 6 „ 
 
 Tartaric acid 6 t 
 
 When the mixture is nearly cold add — 
 
 Sulphuric acid, at full strength 1 lb. 
 
 Oxalic acid (previously dissolved in 2 lbs. hot water) 2 lbs. 
 
 Tin pulp (see below) 6 gals. 
 
 The tin pulp just mentioned is prepared as follows : — Take the strongest 
 double muriate of tin (solution of protochloride of tin), and add as much 
 solution of yellow prussiate as will throw down all the tin as a ferrocyanide. 
 This precipitate is washed in pure water by decantation, and drained on a 
 filter till it becomes a stiff paste. 
 
 No. 4. Another Dark Blue. — 
 
 Water 8 quarts 
 
 Yellow prussiate 4 lbs. 
 
 British gum (pale) 1 
 
mMpgHS 
 
 02 DYEING AND CALICO PRINTING. 
 
 Boil, and add — 
 
 Bisulphate of potash 1 lb. 
 
 Sal-ammoniac 2 lbs. 
 
 Alum £ lb. 
 
 Oxalic acid i ,, 
 
 Sulphuric acid, at 170 T\v , . , . $ ,, 
 
 Tin pulp 1 gal. 
 
 No. 5. Light Blue for Cylinder. — 
 
 Dark blue, No. 3 4 quarts. 
 
 Gum substitute water (4 lbs.) 12 ,, 
 
 No. 6. Blue Standard. — 
 
 Water 1 gal. 
 
 Alum Jib. 
 
 Oxalic acid 4J ozs. 
 
 Yellow prussiate 28 ,, 
 
 Gum substitute water 4 quarts. 
 
 No. 7. Another Blue Standard. Common. — 
 
 Water 8 quarts 
 
 Yellow prussiate 4 lbs. 
 
 Alum fib. 
 
 Sulphuric acid, at 170 Tw i» lbs. 
 
 No. 8. Another Blue. — 
 
 Water 12 quarts 
 
 Starch 4 lbs. 
 
 After boiling add — 
 
 Sal-ammoniac 16 ozs. 
 
 Bisulphate of potash (crystals) 6 lbs. 
 
 Yellow prussiate 4 ,, 
 
 Tartaric acid 4 ,, 
 
 Oxalic acid £ lb. 
 
 Tin pulp 4 quarts. 
 
 No. 9. Another Blue. — 
 
 Water 4 quarts 
 
 Starch 20 ozs. 
 
 Boil, and add — 
 
 Oxalic acid 10 ozs. 
 
 Tartaric acid 3J lbs. 
 
 Yellow prussiate 3J ,, 
 
 When all is thoroughly dissolved and incorporated, and the mixture is grown 
 cold, add — 
 
 Sulphuric acid, at 170 Tw. 8 ozs. 
 
 Tin pulp 1 pint. 
 
 No. 10. Common Blue. — 
 
 Gum water 2 quarts 
 
 Blue standard (No. 7) 1 quart. 
 
 Add a little extract of indigo to " sighten." For patterns of steam-blues see 
 
 pp. 164 and 165. 
 
STEAM COLOURS. 603 
 
 No. 11, Brown. — 
 
 Berry liquor, at 20 Tw i£ gal. 
 
 Brazil-wood liquor, at 8° Tw ii „ 
 
 Alum 3 lbs. 
 
 Lavender liquor (see below) £ § a '- 
 
 Gum Senegal water (6 lbs.) i| gals. 
 
 Nitrate of copper, at ioo° Tw 1 ^ lbs. 
 
 No. 12. Lavender Liquor. — 
 
 Red liquor, at 18 Tw 2 gals. 
 
 Logwood, ground 6 lbs. 
 
 Let steep for forty-eight hours, and strain off the clear liquor. Some makers 
 boil the mixture instead of steeping in the cold. A stronger liquor is made 
 with 10 lbs. of ground logwood to the same amount of red liquor. 
 No. 13. Brown Standard. — 
 
 Bark liquor, at 12 Tw 14 quarts 
 
 Sapan liquor, at 12 Tw 3i ,, 
 
 Logwood liquor, at 12° Tw ii ,, 
 
 Gum substitute water (8 lbs.) 12 ,, 
 
 Alum 3j lbs. 
 
 Chlorate of potash 2 ozs. 
 
 Red prussiate 5 ,, 
 
 From this shades of light brown are made by reducing with gum-water. 
 
 No. 14. Another Brown. — 
 
 Bark liquor, at 12 Tw. 3 quarts 
 
 Sapan liquor, at io° Tw. 2 ,, 
 
 Berry liquor, at 12 Tw. 3 ,, 
 
 Logwood liquor, at 12 Tw 2 ,, 
 
 British gum 12 lbs. 
 
 Boil, and add 
 
 Alum I lb. 
 
 Sal-ammoniac 8 ozs. 
 
 Blue vitriol 8 ,, 
 
 Nitrate of copper, at 8o° Tw £ pint 
 
 Lilac standard (see below) 3 quarts. 
 
 No. 15. Lilac Standard. — 
 
 Logwood liquor, at 20 Tw 4 quarts. 
 
 Heat it to 175°, and dissolve in it — 
 
 Gum Senegal 4 N 38 - 
 
 Red prussiate ^ lb. 
 
 Alum * » 
 
 Oxalic acid 1 oz. 
 
 Binoxalate of potash 2 ozs. 
 
 No. 16. Another Brown. — 
 
 Berry liquor, at 3 Tw 4 quarts 
 
 Peachwood liquor, at 8° Tw 2 ,, 
 
 Logwood liquor, at 8° Tw i pint 
 
 Nitrate of copper, solid i.J lbs. 
 
 Alum J 3 " 
 
604 
 
 DYEING AND CALICO PRINTING. 
 
 Standard Brown (Light). 
 No. 16 a. Light Brown. — 
 
 Brown standard (see next page) i gal. 
 
 Gum-water (4 lbs.) 1 ,, 
 
 Acetate of alumina, at 18 Tw 1 pint 
 
 Nitrate of copper 1 quart. 
 
 Mix well. When printed, age and let lie four nights, and pass through dilut 
 arseniate of soda, at i8o° F. Wash with hot water, and run through very 
 dilute chloride of lime on the mangle, dry, and finish. 
 
 No. 166. Dark Brown. — Same colour as No. 16 a. When printed, steam 
 thirty minutes, age two nights, wash off in weak solution of bichrome ; wash 
 well, dry, and finish. 
 
 Standard Brown (Dark) 
 
STEAM COLOURS. 605 
 
 No. 16c. Brown Standard, referred to in Nos. 16 a and b. — 
 
 Catechu, cubic 25 lbs. 
 
 Water 8 gals. 
 
 Boil eight hours, and add — 
 
 Acetic acid 2. J quarts 
 
 Then dissolve — 
 
 Sal-ammoniac 10 lbs. 
 
 In — Water ii gals. 
 
 Mix both liquids well ; let settle, and thicken the clear liquor with gum-water. 
 No. 17. Buff (Chamois). — 
 
 Madder liquor 3 gals. 
 
 Bark liquor, at io° Tw 4 quarts 
 
 Red liquor, at 14 Tw 2 gals. 
 
 Starch 7 lbs. 
 
 Boil, and add — 
 
 Crystals of tin 2 ozs. 
 
 No. 18. Chocolate (for Cylinder-Work).— 
 
 Logwood liquor, at 12 Tw 3 gals. 
 
 Sapan liquor, at 12 Tw 2 ,, 
 
 Nitrate of alumina (see below) 1 gal. 
 
 Bark liquor, at 12 Tw J ,, 
 
 Water 4 gals. 
 
 Starch 17 lbs. 
 
 Boil, and then add — 
 
 Chlorate of potash £ lb. 
 
 Red prussiate 2^ lbs. 
 
 No. 19. Nitrate 0/ Alumina. — 
 
 Boiling water 8 gals. 
 
 Nitrate of lead, crystals 24 lbs. 
 
 Alum 24 ,, 
 
 Carbonate of soda, crystals 5 ,, 
 
 Stir till dissolved; let settle, and draw off the clear liquid for use. 
 No. 20. Another Chocolate. — 
 
 Sapan liquor, at 9 Tw 12 quarts 
 
 Nitrate of alumina 3 ,, 
 
 Logwood liquor, at 12 Tw. 6 „ 
 
 Yellow prussiate 6 ozs. 
 
 Red prussiate 6 „ 
 
 Chlorate of potash 6 ,, 
 
 Starch g lbs. 
 
 This formula requires well boiling and mixing. 
 No. 21. Another Chocolate. — 
 
 Sapan liquor, at 8° Tw 5 gals. 
 
 Red liquor, at 16° Tw. 6 quarts 
 
 Nitrate of alumina 6 ,, 
 
 Logwood liquor, at 18 Tw 2 gals. 
 
 Bark liquor, at 18 Tw 3 quarts 
 
 Starch 16 lbs. 
 
Si 
 
 606 DYEING AND CALICO PRINTING. 
 
 Boil, and add when cold — 
 
 Red prussiate 1 lb. 
 
 Yellow prussiate 2 lbs. 
 
 Chlorate of potash 2 „ 
 
 These receipts admit of almost infinite variations. 
 
 No. 22. Cinnamon. — 
 
 Cochineal liquor, at 8° Tw 1 quart 
 
 Logwood liquor, at 8° Tw 1 ,, 
 
 Berry liquor, at io° Tw 1 ,, 
 
 Alum 6 ozs. 
 
 Cream of tartar 4 ,, 
 
 Starch 8 „ 
 
 Boil, and add whilst still warm — 
 
 Tin crystals (protochloride) 3 ozs. 
 
 No. 23. Drab. — 
 
 Lavender liquor 4 gals. 
 
 Blue standard 4 ,, 
 
 Bark liquor, at 8° Tw 1 gal. 
 
 Gum-water, from 40 to 70 gals. 
 
 No. 24. Dark Drab. — 
 
 Berry liquor, at 12 Tw 4 quarts 
 
 Gum-substitute 7 lbs. 
 
 Boil and cool, and next add — 
 
 Alum 24 ozs. 
 
 Copperas 16 ,, 
 
 Logwood liquor, at 2° Tw 1 quart 
 
 Cochineal liquor, at 3 Tw 1 ,, 
 
 No. 25. Another Drab. 
 
 Boiling water 3 quarts 
 
 " Lilac standard " 14 pints 
 
 Bark liquor, at 30 Tw | pint 
 
 Yellow prussiate (dissolved in 1 pint hot water) . . 1 oz. 
 This mixture is thickened with gum according to circumstances. 
 
 No. 26. The Lilac Standard, above mentioned, is prepared thus: — 
 
 Logwood liquor, at 12 Tw 8 gals. 
 
 Red liquor, at 18 Tw 8 ,, 
 
 Oxalic acid 4 lbs. 
 
 Sal-ammoniac 5 „ 
 
 Acetate of copper, crystallised 2.$ „ 
 
 No. 27. Green (for Cylinder-Work). — 
 
 Berry liquor, at 12 Tw. .. 7 gals. 
 
 Yellow prussiate 15 lbs. 
 
 Alum 8 „ 
 
 Gum-substitute 28 „ 
 
 Boil, and add — 
 
 Tin crystals 2 lbs. 
 
 Oxalic acid , 2 „ 
 
STEAM COLOURS. 607 
 
 No. 28. Green for Block-Work. — 
 
 Hot water 6 gals. 
 
 Yellow prussiate 28 lbs. 
 
 Mix meantime in a separate vessel — 
 
 Water 2 gals. 
 
 Double muriate of tin, at 120 Tw 1 gal. 
 
 Gum Senegal water (6 lbs.) 10 gals. 
 
 Mix these two solutions by pouring backwards and forwards, and stirring very 
 briskly. When the whole is perfectly incorporated and clear add — 
 
 Berry liquor, at io° Tw 12 gals. 
 
 Tartaric acid 10 lbs. 
 
 Oxalic acid (dissolved in 5 gals, water) 7.\ ,, 
 
 Acetic acid 3 quarts 
 
 Extract of indigo z\ gills. 
 
 No. 29. Green [inferior quality). — 
 
 Starch 12 lbs. 
 
 Bark liquor, at 16 Tw 8 gals. 
 
 Boil, and add — 
 
 Alum 3 lbs. 
 
 Oxalic acid £ lb. 
 
 Tin crystals 1 ,, 
 
 When nearly cold add — 
 
 Tartaric acid 10 lbs. 
 
 Yellow prussiate 20 „ 
 
 Tin pulp 1 gal. 
 
 No. 30. Green for Blotch Grounds. — 
 
 Bark liquor, at io° Tw 8 gals. 
 
 Starch 12 lbs. 
 
 Boil together, and add — 
 
 Alum 5 lbs. 
 
 Yellow prussiate . . > 12 ,, 
 
 Tartaric acid 6 ,, 
 
 Oxalic acid 1^ lb. 
 
 Tin pulp J gal. 
 
 Steam-greens after printing are frequently brightened, or " raised " as it is 
 technically called, by passing through a weak bath of bichrome. 
 
 No. 30 a. Aloes Green. — 
 
 Chrysammide (see p. 417) 2 grms. 
 
 Gum-water, according to shade. 
 After steaming, this mixture gives a fine moss-green, not affected by boiling 
 water, or madder and garancin baths. Thus a variety of modifications can 
 be produced. A design may be printed by this means in deep green ; a green 
 ground may be obtained. Iron and alumina mordants may then be printed 
 on, and the pieces dyed in the madder or garancin beck. The result will then 
 be — in the one case, a white ground, with green, red, purple, chocolate, and 
 black figures; or, in the other case, a green ground with a design in the four 
 latter colours, or any of them. 
 
iM 
 
 '^■k^k^-'-t 
 
 608 
 
 DYEING AND CALICO PRINTING. 
 
 No. 31. Dark Grey. — 
 
 Gum-water 4 gals. 
 
 Lilac standard. No. 26 2 „ 
 
 Yellow prussiate 4 lbs. 
 
 Hot water 1 gal. 
 
 No. 32. Lavender. — 
 
 Lavender liquor, No. 12 4 gals. 
 
 Blue standard, No. 6 4 ,, 
 
 Gum-water (according to shade) 24 to 48 gals. 
 
 No. 33. Lilac (Dark). — 
 
 Pink standard (see below) 6 gals. 
 
 Purple standard (see below) 2 „ 
 
 Gum-substitute 20 lbs. 
 
 No. 34. Lilac (Light). — 
 
 Pink standard 6 gals. 
 
 Purple standard 2 ,, 
 
 Gum-water 6 ,, 
 
 No. 35. Pink Standard. — 
 
 Cochineal liquor, at 6° Tw 4 gals. 
 
 Alum 2 lbs. 
 
 Cream of tartar 2 „ 
 
 Oxalic acid J lb. 
 
 This mixture, thickened with 4 gals, of thick gum Senegal water, forms a pink 
 steam-colour. The proportions of alum, cream of tartar, and oxalic acid used 
 by different printers vary considerably, some putting, to the above quantity of 
 cochineal liquor, only i£ lbs. alum, 12 ozs. cream of tartar, and 4 ozs. of 
 oxalic acid, whilst others employ intermediate quantities. 
 
 No. 36. Purple Standard. 
 
 Logwood liquor, at 12° Tw 2 gals. 
 
 Alum 12 ozs. 
 
 Red prussiate 8 ,, 
 
 Oxalic acid 4 ,, 
 
 This quantity, mixed with 8 gals, gum substitute water, forms a good cylinder 
 colour. If wanted for block-printing, 12 gallons of gum-water are required. 
 Here, also, the amount of salts and acids varies in different establishments. 
 In some receipts, to 2 gals, of logwood liquor, 1 lb. of red prussiate, i\ lbs. 
 alum, 2 ozs. of oxalic acid, and 4 ozs. of oxalate of potash are used. 
 
 No. 37. Pink (Sapan Wood). — 
 
 Sapan liquor, at 3 Tw 2 gals. 
 
 Pink salt 2 lbs. 
 
 Sal-ammoniac 1 lb. 
 
 Oxalic acid 2 ozs. 
 
 Sulphate of copper 2 ,, 
 
 Gum-water (thick) 2 gals. 
 

■H 
 
 B 
 
 iphpp 
 
STEAM COLOURS. 609 
 
 No. 38. Pink (Sapan and Cochineal mixed). — 
 
 Sapan liquor, at 8° T\v . . 5 gals. 
 
 Cochineal liquor, at 8° T\v .. 1 gal. 
 
 Nitrate of alumina £ ,, 
 
 Alum 3 lbs. 
 
 Oxalic acid 2 ozs. 
 
 Chlorate of potash 8 ,, 
 
 After the other ingredients are incorporated there is added — 
 
 Gum water 12 gals. 
 
 No. 39. Pink (Cochineal). — 
 
 Cochineal liquor, at 6° Tw 2 gals. 
 
 Heat to about 168° F., and dissolve — 
 
 Alum , 12 ozs. 
 
 Cream of tartar 6 ,, 
 
 Oxalic acid 1 oz. 
 
 This colour is mixed with various amounts of gum-water, according to the 
 
 shades required. For other cochineal pinks, crimsons and reds, &c, see under 
 
 " Cochineal." 
 
 Cochineal Pink. 
 
 No. 39 a. Cochineal Pink. — 
 
 Cochineal liquor, at 8° Tw " 1 gal. 
 
 Starch U lbs. 
 
 iBoil a little, and add — 
 
 Oxalic acid 3 ozs. 
 
 (Dissolve, and strain for printing. When printed, steam forty minutes at 3 lbs. 
 rpressure ; let lie one night ; run through a very dilute solution of alum on the 
 imangle, and finish. 
 
 a r 
 
■ 
 
 6io DYEINO AND CALICO PRINTING. 
 
 No. 40. Purple, Ordinary. — 
 
 Logwood liquor, at io° T\v. . « . . 6 gals. 
 
 Red liquor, at 18 Tw, . , . . . . , 6 ,, 
 
 In which latter dissolve separately — 
 
 Carbonate of soda, crystals ij lbs. 
 
 Oxalic acid .. . . 3 ,, 
 
 When all is dissolved add — 
 
 Gum Senegal, in powder 36 lbs. 
 
 No. 41. Purple, Deep. — 
 
 Logwood liquor, at 16 Tw 1 gal. 
 
 Red liquor, at 20 Tw 1 ,, 
 
 Soda crystals 4 ozs. 
 
 Red prussiate Jib. 
 
 Oxalic acid \ „ 
 
 Gum Senegal 6J lbs. 
 
 No. 42. Red, Dark (for Cylinder). — 
 
 Sapan liquor, at 12' Tw 2 gals. 
 
 Bark liquor, at 8° Tw £ gal. 
 
 Nitrate of alumina £ „ 
 
 Chlorate of potash 4 ozs. 
 
 Alum .. .. 12 ,, 
 
 Starch 6> „ 
 
 Gum substitute lib. 
 
 No. 43. Red. — 
 
 Sapan liquor, at io° Tw 4 gals. 
 
 Bark liquor, at 18 Tw i£ quarts 
 
 Red liquor, at 20 Tw ii ,, 
 
 Alum 2j lbs. 
 
 Chloride of copper (crystals) 12.J ozs. 
 
 No. 44. Red. — 
 
 Sapan liquor, at 8° Tw 2 gals. 
 
 Bark liquor, at 12 Tw i£ quarts 
 
 Nitrate of alumina ij „ 
 
 Alum i^ lbs. 
 
 Chlorate of potash 2 J ozs. 
 
 Starch . . . . . 3? lbs. 
 
 No. 44 a. Corallin Red. — 
 
 Corallin 100 grms. 
 
 Alcohol 400 ,1 
 
 Dissolve, and add — 
 
 Solution of casein 2250 grms. 
 
 To prepare this solution take — 
 
 Casein 100 grms. 
 
 Water 300 ,, 
 
 Ammonia . . . . 20 ,, 
 
 Others add oxide of zinc to the above mixture, or mix intimately the alcoholic 
 solution of corallin with oxide of zinc, and thicken with albumen. Or the 
 
STEAM COLOURS. 6u 
 
 solution of corallin may be mixed with magnesia and oxide of zinc, and 
 thickened either with albumen or with glycerin and gum-water. 
 
 No. 446. — Aloes, Rose. 
 
 Gum-water I litre 
 
 Chrysammic acid (p. 417) 2 grms. 
 
 This mixture, without steaming, produces a rose on cotton, silk, or wool. The 
 shades resist washing, and are not modified if the pieces have been prepared 
 with stannate of soda. On steaming, the rose is converted into a violet. 
 
 No. 44 c. Deep Red [Artificial Alizarin). — 
 
 Alizarin paste, at 15 per cent . .. 800 grms. 
 
 Acetic acid, at 6° Baume .. .. 1 litre 
 
 Water 2 litres 
 
 Olive oil 200 grms. 
 
 Acetate of lime, at io° Baume 200 „ 
 
 Wheat starch 5°° >> 
 
 Boil well, stir till cool, and incorporate — 
 
 Acetate of alumina 200 grms. 
 
 No. 44 d. Rose-Colour. — 
 
 Alizarin paste, at 15 per cent 1600 grms. 
 
 Thickening for reds 8 litres 
 
 Acetate of alumina, at 12 Baume 500 grms. 
 
 Acetate of lime, at 16 Baume 250 ,, 
 
 The paler the shade required the more thickening must be used. (See also 
 p. 225). 
 
 No. 45. Stone-Colour. — 
 
 Lavender liquor, No. 12 4 gals. 
 
 Blue standard, No. 6 6 ,, 
 
 Bark liquor, at 12" Tw 1 gal. 
 
 Gum-water, according to shade 40 to 70 gals. 
 
 No. 46. Yellow. — 
 
 Berry liquor, at 12 Tw 4 S ais - 
 
 Alum ij lbs. 
 
 No. 47. Yellow. — 
 
 Bark liquor, at 8° Tw 4 g als - 
 
 Red liquor, at 18 Tw i gal. 
 
 Nitrate of alumina £ ,, 
 
 Tin crystals 12 ozs. 
 
 Starch 5 lb s- 
 
 No. 48. Pale Yellow. — 
 
 Berry liquor, at 4 Tw 1 gal. 
 
 Flour H lbs - 
 
 Boil, and add — 
 
 Alum 9 ozs. 
 
 Dissolve, and strain. When printed, steam thirty minutes at 3 lbs. pressure; 
 let lie one night, and run through a dilute solution of alum on the mangle, 
 and finish. 
 
 2R 2 
 
6l2 
 
 DYEING AND CALICO PRINTING. 
 
 Pale Yellow from Persian Berries. 
 
 No. 49. Dark Yellotv. — 
 
 Berry liquor, at 4° Tw 1 gal. 
 
 Flour ii lbs. 
 
 Boil, and add — 
 
 Alum g ozs. 
 
 When cool add — 
 
 Tin crystals .. ; 3 ozs. 
 
 When dissolved, strain. After printing, steam for thirty minutes, as in No. 48. 
 
 Dark Yellow from Persian Berries. 
 
 For other patterns, and particulars of various coal-tar colours fixed by the 
 steam process, the reader is referred to pp. 206, 207, 217, 218, 225, and 226. 
 
HOFMANN VIOLET. 
 
 613 
 
 Hofmann Violet on Calico. 
 The colour is mixed with red liquor, and with a solution of arsenious acid 
 in water to which some glycerin has been added, as directed on p. 207. Both 
 these compounds together form the mordant. After steaming for an hour it is 
 gently soaped. The colour is thickened with gum and starch. 
 
 Hofmann Violet. 
 
 Delaines. 
 
 The method of printing delaines, and other mixed fabrics composed of 
 wool, or worsted, with a cotton warp, may be treated as an appendix to the 
 steam style. The preparation of the goods is different, and in most cases 
 the colours are mixed differently, so as to be suitable both for the cotton and 
 wool. The steaming and subsequent operations are very similar to those 
 recommended for calico. The first step is the bleaching of the goods, which 
 is exceedingly important, and which is performed by means of the fumes of 
 burning sulphur. For this purpose they are hung up in a close brick or stone 
 chamber, and sulphur, being placed upon the floor in iron dishes, is set fire to, 
 and the door is tightly closed. After the lapse of some hours the pieces are 
 taken out and washed. The following improved apparatus (Figs. 37 and 38) 
 is the invention of Mr. John Thorn. 
 
 a (Fig 37) represents the roof of the chamber, made of sheet-lead, of 4 lbs. 
 to the square foot. B is a lead pipe, of 1 inch diameter, to carry off any excess 
 of sulphurous gas. c c are rolls of pieces, to enter the chamber at one side 
 and come out at the other, d d are wooden cylinders, turning on iron axles. 
 EE represents the flooring, made of perforated tiles, similar to the floor of a 
 malt-kiln, through which the sulphurous acid gas enters. 
 
 Fig. 38 represents the sulphur-chamber, 6 feet long by 4 broad and 5 high, 
 fitted with two windows, placed opposite to each other, f is an iron tray in 
 
614 
 
 DYEINO AND CALICO PRINTING. 
 
 which the sulphur is burned, placed on a sloping flag-stone, inclined to the 
 chamber at i inch in the foot. There is a slide by which fresh supplies of 
 sulphur may be introduced, and air admitted, as required. The air-opening is 
 
 Fig. 37. 
 
 Fig. 38. 
 
 from £ an inch to 1 inch. Delaines, as well as goods consisting entirely of 
 wool or of worsted, are sometimes bleached by means of concentrated solu- 
 tions of the bisulphites of soda or of magnesia. 
 
PRINTING DELAINES. 615 
 
 The preparing, which is the next step, is also of capital importance. The 
 pieces are generally padded twice, by means of a machine with wooden 
 rollers, in stannate of soda. Next they are run through water mixed with 
 sulphuric acid and marking 3 Tw., gently washed and partly dried, and, 
 lastly, they are twice padded in dilute sulpho-muriate of tin, at about 4 Tw. 
 Some printers, however, prepare delaines like calico, by merely padding in 
 stannate, souring, &c, as described on p. 600. Others use a variety of 
 " prepares." Thus the pieces are padded four times, in a solution formed of 
 equal parts of bichloride of tin, at 120 Tw., and double muriate of tin (proto- 
 chloride), at 120 Tw., and let down with water to io° Tw. ; then in dilute 
 sulphuric acid, at 4 C Tw. ; then in chloride of lime, at o - 5° Tw., washed, placed 
 in the hydro-extra&or, and dried. Whatever be the " prepare," it is advisable 
 to pass the pieces from it, without washing, directly into the weak solution of 
 chloride of lime just mentioned, after which they are washed and dried. 
 
 The solution of sulpho-muriate of tin above mentioned is prepared by 
 mixing — 
 
 Double muriate of tin, at 120 Tw 3 quarts. 
 
 Sulphuric acid, at 170 Tw. 1 quart. 
 
 Mix together very gradually, and add — 
 
 Muriatic acid 4 quarts. 
 
 For use, reduce with water to 4 Tw. When the pieces, after preparing, are 
 ready for printing, they are padded in weak gum Senegal water (J lb. per 
 gallon), and dried. 
 
 The following are some of the colours ordinarily used for printing 
 delaines : — 
 
 No. 1. Black.— 
 
 Logwood liquor, at 12 Tw 3 gals. 
 
 Starch 3 lbs. 
 
 Boil well together, and when the mixture has cooled to about 88° to 90 F. 
 add— 
 
 Nitrate of iron, at 85 Tw 1 quart. 
 
 No. 2. Black. — 
 
 Logwood liquor, at 8° Tw 2 gals. 
 
 Bark liquor, at io° Tw 3 pints. 
 
 Extract: of indigo 5 ozs. 
 
 Pyroligneous acid, at 7° Tw 1 quart. 
 
 Bichromate £ oz. 
 
 Flour 4 lbs. 
 
 British gum i lb. 
 
 Boil the mixture, and when it is nearly cold add — 
 
 Sal-ammoniac J lb. 
 
 Muriate of iron, at 8o° Tw 1 pint. 
 
 Nitrate of iron, at 8o° Tw 1 ,, 
 
 No. 3. Blue, Dark or Royal. — 
 
 Water 6 gals. 
 
 Starch 6J lbs. 
 
 Sal-ammoniac 2J lbs. 
 
^M 
 
 616 DYEING AND CALICO PRINTING. 
 
 Boil the whole well and add — 
 
 Tin pulp 6 gals. 
 
 Stir and mix well in, and add — 
 
 Yellow prussiate, ground 16 lbs. 
 
 Red prussiate 8 ,, 
 
 Tartaric acid 24 ,, 
 
 Oxalic acid (dissolved in 2 quarts hot water) . . . . i£ ,, 
 
 No. 4. Medium Blue. — 
 
 Standard blue (No. 6) 6 gals. 
 
 Oxymuriate of tin, at 120 Tw i| quarts. 
 
 The latter ingredient is added gradually, and the mixture very well stirred. 
 
 Extract of indigo 2\ quarts. 
 
 No. 5. Blue, Pale. — 
 
 Dark blue colour, No. 3 1 gal. 
 
 Gum water 7 gals. 
 
 For blotch- or ground-blues the proportion of gum-water is doubled. 
 No. 6. Standard Blue. — 
 
 Yellow prussiate 10 lbs. 
 
 Alum 3 ,, 
 
 Oxalic acid 2 ,, 
 
 Water 4 gals. 
 
 Gum-water (6 lbs. to the gallon) 4 „ 
 
 No. 7. Royal Blue. — 
 
 Water 4 gals. 
 
 Starch 10 lbs. 
 
 Solution of red prussiate, at 30 Tw 4 gals. 
 
 Gum tragacanth water 2 quarts. 
 
 Boil and add — 
 
 Tin pulp 12 quarts. 
 
 Tartaric acid 4$ lbs. 
 
 Oxalic acid 12 ozs. 
 
 When cold add — 
 
 Yellow prussiate 16 lbs. 
 
 Tartaric acid 20 ,, 
 
 No. 8. Blue, Dark Blotch.— 
 
 Water 7 gals. 
 
 Starch 8 lbs. 
 
 Solution of red prussiate, at 30 Tw 3 gals. 
 
 Solution of gum tragacanth 3 quarts. 
 
 Boil the mixture, and add while still hot. 
 
 Tin pulp 3 gals. 
 
 Tartaric acid 8 lbs. 
 
 Oxalic acid 12 ozs. 
 
 When cold add the clear liquid from the following mixture : — 
 
 Prussiate of potash 16 lbs. 
 
 Tartaric acid 16 ,, 
 
 Hot water 5 gals. 
 
I 
 
 PRINTING DELAINES. 
 
 No. g. Buff Standard. — 
 
 Cochineal liquor, at 8° Tw I quart. 
 
 Berry liquor, at 10° Tw. 3J quarts. 
 
 Red liquor, No. 41 1 quart. 
 
 Oxalic acid 20 ozs. 
 
 Gum-water is added according to the shades required. 
 
 No. 10. Buff.— 
 
 Catechu liquor, £ lb. per gallon 5 quarts. 
 
 Alum 8 ozs. 
 
 Dissolved in — 
 
 Hot water 1 quart. 
 
 Acetate of copper 3 ozs. 
 
 Nitrate of copper 10 ,, 
 
 Thicken with gum-water according to shade. 
 
 No. 11. Dark Brown. — 
 
 Sapan liquor, at 8° Tw 2$ quarts. 
 
 Logwood liquor, at 12* Tw 1 pint. 
 
 Bark liquor, at io° Tw 5 quarts. 
 
 Alum 12 ozs. 
 
 Chlorate of potash 1 oz. 
 
 Gum-substitute 6 lbs. 
 
 Boil and add — 
 
 Red prussiate 4 ozs. 
 
 Oxalic acid 2 ,, 
 
 No. 12. Pale Browns.— Reduce No. 11 with gum-water. 
 
 No. 13.— 
 
 Berry liquor, at 8* Tw 5 quarts. 
 
 Alum i£ lbs. 
 
 Orchil liquor, at 8° Tw 1 quart. 
 
 Sapan liquor, at 8° Tw 1 pint. 
 
 Logwood liquor, at io° Tw i ,, 
 
 Starch lib. 
 
 Boil and add — 
 
 Oxalic acid 2 ozs. 
 
 No. 14. Brazil-ivood Brown. — 
 
 Brazil- or peach-wood liquor, at 9 Tw 1 gal. 
 
 Berry liquor, at 18 Tw 1 ,, 
 
 Orchil liquor, at 12° Tw £ ,, 
 
 Starch 2 lbs. 
 
 Boil and add — 
 
 Alum i£ lbs. 
 
 Sal-ammoniac 4 ozs. 
 
 Acetate of copper 2 ,, 
 
 617 
 
618 DYEING AND CALICO PRINTING. 
 
 No. 15. Chocolate, Dark. — 
 
 Sapan liquor, at ii° Tw .. 2 quarts. 
 
 Bark liquor, at 14 Tw £ pint. 
 
 Logwood liquor, at 14 Tw I ,, 
 
 Gum 3 lbs. 
 
 Alum 12 ozs. 
 
 Chloride of copper (crystals) 8 ,, 
 
 Sal-ammoniac 2j ,, 
 
 No. 16. Chocolate, Dark. — 
 
 Sapan liquor, at 8° Tw. . . , 5 gals. 
 
 Red liquor, at 16° Tw ij „ 
 
 Logwood liquor, at io° Tw 2 ,, 
 
 Nitrate of alumina i£ ,, 
 
 Bark liquor, at 18 Tw 3 quarts. 
 
 Starch 15 lbs. 
 
 Boil, and when nearly cold add — 
 
 Red prussiate of potash 8 ozs. 
 
 Yellow prussiate 1 lb. 
 
 Chlorate of potash 1 ,, 
 
 No. 17. Chocolate. — 
 
 Sapan liquor, at 300 Tw 2 gals. 
 
 Red liquor, at 24 Tw 2 ,, 
 
 Acetic acid (weak) 1 pint. 
 
 Starch 6 lbs. 
 
 Gum-substitute 8 ,, 
 
 Boil, and add — 
 
 Alum 1 lb. 
 
 Dissolved in — 
 
 Logwood liquor, at 30 Tw 3 pints. 
 
 Bark liquor, at 30 Tw . . 1 quart. 
 
 Then add— 
 
 Chlorate of potash 2 lbs. 
 
 Dissolved in — 
 
 Gum tragacanth water 3 quarts. 
 
 Sal-ammoniac lib. 
 
 Sulphate of copper 6 ozs. 
 
 No. 18. Chocolate. — 
 
 Sapan liquor, at 20 Tw 2 quarts. 
 
 Nitrate of alumina 2 „ 
 
 Bark liquor, at 30 Tw 1 pint. 
 
 Logwood liquor, at 30° Tw 1 > pints. 
 
 Gum, in powder 7 lbs. 
 
 Chlorate of potash 5 ozs. 
 
 Dissolved in — 
 
 Boiling water 1 J quarts. 
 
 Sulphate of copper ij ozs. 
 
I 
 
 PRINTING DELAINES. 
 
 No. 19. Cinnamon (Block). — 
 
 Bark liquor, at 20 Tvv 2 gals. 
 
 Cochineal, ground z\ lbs. 
 
 Digest at a gentle heat, strain, and thicken with — 
 
 Gum Senegal 7 lbs. 
 
 Extract of indigo 6 ozs. 
 
 Tin crystals 18 „ 
 
 No. 20. Dove Colour. — 
 
 Dove blue (see below, No. 21) 6 quarts. 
 
 Lavender liquor (see No. 12, steam on calico) . . 4 ,, 
 
 Gum Senegal water (6 lbs. per gal.) 8 ,, 
 
 No. 21. Dove Blue. — 
 
 Water 5 quarts. 
 
 Yellow prussiate 2 lbs. 
 
 Alum 2 ,, 
 
 Extract of indigo 1 pint. 
 
 Gum-water (6 lbs. per gal.) 5 quarts. 
 
 No. 22. Drab Standard. — 
 
 Purple liquor (see below, No. 23.) 6 quarts. 
 
 Bark liquor, at io° Tw 1 quart. 
 
 Red liquor, at 20 Tw J pint. 
 
 Extract of indigo J ,, 
 
 Different shades are made by the addition of gum-water. 
 
 No. 23. Purple Liquor. — 
 
 Lavender liquor (No. 12, steams for calico) . . . . 1 gal. 
 
 Oxalic acid 3 ozs. 
 
 No. 24. Drab Standard, Silvery. — 
 
 Gall liquor, at 12 Tw 3 gals. 
 
 Standard blue (No. 6) 2 ,, 
 
 Lavender liquor (No. 12, steams for calico) . . . . 1 gal. 
 
 No. 25. — Drab, Dark. — 
 
 Gall liquor, at 12 Tw 2 quarts. 
 
 Berry liquor, at io° Tw r pint. 
 
 Cochineal liquor, at 6° Tw 1 gill. 
 
 Iron liquor, at 24° Tw 1 ,, 
 
 Gum-water 3 quarts. 
 
 No. 26. Drab, Dark. — 
 
 Lavender liquor 3 quarts. 
 
 Blue standard, No. 6 2 „ 
 
 Berry liquor, at 6° Tw 3 pints. 
 
 Gum-substitute 5 lbs. 
 
 No. 27. Green — 
 
 Berry liquor or bark liquor, at 12" Tw 4 gals. 
 
 Alum 3 lbs. 
 
 Starch 6 ,, 
 
 619 
 
BBBBBBBBBBBBBBBBI 
 
 620 DYEINO AND CALICO PRINTING. 
 
 Boil and add — 
 
 Yellow prussiate, ground 6 lbs. 
 
 Tin crystals 1 lb. 
 
 Oxalic acid 1 ,, 
 
 Extract of indigo 2f pints. 
 
 No. 28. Pale Green. — 
 
 Berry liquor, at 6° Tw 3 quarts. 
 
 Yellow prussiate if lbs. 
 
 Alum 94 ozs. 
 
 Acetic acid J pint. 
 
 Gum Senegal water (4 lbs. per gal.) 16 quarts. 
 
 Muriate of tin, at 120 Tw 8 ozs. 
 
 Extract of indigo f pint. 
 
 No. 29. Green, Medium. — 
 
 Berry liquor, at 8° Tw 8 quarts. 
 
 Yellow prussiate 3 lbs. 
 
 Alum i\ „ 
 
 Gum-water (at 6 lbs. per gal.) 7 quarts. 
 
 Water 1 quart. 
 
 Acetic acid 1 ,, 
 
 Muriate of tin, at 120 Tw 1402s. (weight.) 
 
 Extract of indigo 1 pint. 
 
 No. 30. Green, Dark. — 
 
 Berry liquor, at 14° Tw 1 gal. 
 
 Red liquor, at 20 Tw 5 pints. 
 
 Starch 1 lb. 13 ozs. 
 
 Boil and add — 
 
 Extract of indigo 1 lb. 1 oz. 
 
 Alum 10 ozs. 
 
 Yellow prussiate 3 lbs. 2 ozs. 
 
 Tartaric acid 1 lb. 4 ozs. 
 
 Oxalic acid 5 ozs. 
 
 No. 31. Green, Dark. — 
 
 Bark liquor, at 15 Tw 2 gals. 
 
 Starch 3i lbs. 
 
 Gum-substitute lib. 
 
 Boii and add — 
 
 Alum 1 1 lbs. 
 
 Crystals of tin 4 ozs. 
 
 Tartaric acid 34 lbs. 
 
 Yellow prussiate 3 J ,, 
 
 Oxalic acid (in 1 gill hot water) 4 ozs. 
 
 Extract of indigo 1 pint. 
 
 No. 32. Green, Dark. — 
 
 Bark liquor, at 13° Tw 1 gal. 
 
 Starch i\ lbs. 
 
PRINTING DELAINES. 621 
 
 Boil and add — 
 
 Alum 7J ozs. 
 
 Cool and add — 
 
 Yellow prussiate 1 lb. i£ ozs. 
 
 Tartaric acid 8| ozs. 
 
 Oxalic acid 2 ,, 
 
 Extract of indigo 6 ,, 
 
 Tin pulp 12 ozs. measure. 
 
 No. 33. Green — 
 
 Bark liquor, at 6° T\v 1 gal. 
 
 Starch i£ lbs. 
 
 Boil and add— 
 
 Alum 4 ozs. 
 
 Cool and add — 
 
 Yellow prussiate 9 ozs. 
 
 Oxalic acid 3 ,, 
 
 Extract of indigo 10 ,, 
 
 Tin pulp J gill. 
 
 No. 34. Green. — 
 
 Berry liquor, at 13 Tw 1 gal. 
 
 Red liquor, at 14 Tw 1 quart. 
 
 Alum (in £ gal. boiling water) J lb. 
 
 Yellow prussiate fib. 
 
 Oxalic acid £ ,, 
 
 Extract of indigo $ ,, 
 
 Tin pulp i „ 
 
 Gum-water 2 gals. 
 
 It is plain that these colours may be modified to an indefinite extent both 
 in depth of shade and in tones bordering more on the blue or on the yellow. 
 
 No. 35. Lilac. — 
 
 Lavender liquor (No. 12 steams on calico) . . . . 2 gals. 
 
 Oxalic acid 6 ozs. 
 
 Extract of indigo 2 ,, 
 
 No. 36. Lilac, Dark. 
 
 Logwood liquor, at 12° Tw 4 gals. 
 
 Alum 3 J lbs. 
 
 Gum 12 ,, 
 
 No. 37. Lilac, Dark. — 
 
 Lavender liquor (No. 12, steams calico, strongest) 1 gal. 
 
 Pink standard (No. 35, do. do. ) 1 ,, 
 
 Gum-substitute 2^ lbs. 
 
 No. 38. Olive.— 
 
 Lavender liquor (as above) 1 quart 
 
 Berry liquor, at io° Tw 2 quarts 
 
 Gum Senegal water (8 lbs. per gallon) 2 ,, 
 
622 DYEING AND CALICO PRINTING. 
 
 No. 3g. Olive. — 
 
 Dark green (any of the above mentioned) .. . . 2 quarts 
 
 Lavender liquor (strongest) 1 quart. 
 
 No. 40. Orange. — 
 
 Berry liquor, at io° Tw. 3 gals. 
 
 Gum Senegal 9 lbs. 
 
 Red mordant (see No. 41) 3 pints 
 
 Tin crystals 12 02s. 
 
 Boil the whole for fifteen minutes. 
 
 No. 41. Red Mordant. — 
 
 Water, hot 1 gal. 
 
 Alum 6 lbs. 
 
 Acetate of lead, white 3 ,, 
 
 Stir till all is dissolved; let settle, and decant the clear liquid for use. 
 No. 42. Orange, Red. — 
 
 Bark liquor, at 19° Tw 2 quarts 
 
 Starch 1^ lbs. 
 
 Water i£ quarts. 
 
 Boil, and add — 
 
 Cochineal liquor, at 8° Tw £ pint 
 
 Tin crystals 9 ozs. 
 
 The tone can be modified by increasing or diminishing the proportion of 
 cochineal liquor. 
 
 No. 43. Pink. — 
 
 Ammoniacal extract of cochineal, at io° Tw. . . 2 gals. 
 
 Best tartar i lb. 
 
 Alum 1 j, 
 
 Gum 8 lbs. 
 
 No. 44. Purple. — 
 
 Lavender liquor (strongest) 1 gal. 
 
 Binoxalate of potash 2 ozs. 
 
 Oxalic acid 2 ,, 
 
 This colour may be modified by adding to it various proportions of a 
 mixture of — 
 
 Red liquor, at 18 Tw 3 quarts 
 
 Extradt of indigo, neutral 1 quart. 
 
 No. 45. Red, Pale. — 
 
 Ammoniacal cochineal liquor 1 gal. 
 
 Alum 4 ozs. 
 
 Tin crystals 4 >> 
 
 Oxalic acid 4 »> 
 
 Gum Senegal water (6 lbs. per gallon) 1 gal. 
 
 No. 46. Red, Blotch.— 
 
 Cochineal liquor, at 6° Tw 12 gals. 
 
 Berry liquor, at 9 Tw 2 ,, 
 
 Starch 21 lbs. 
 
 Oxalic acid 4i ,, 
 
 Tin crystals 4i „ 
 
PRINTING DELAINES. 
 No. 47. Red, Amaranth. — 
 
 Ammoniacal cochineal paste 15 lbs. 
 
 Boiling water 4 g a l s . 
 
 Acetic acid 1 quart 
 
 Alum 1 lb. 
 
 Gum 18 lbs. 
 
 Dissolve, and add — 
 
 Hydrochloric acid (pure) 1 quart 
 
 Bichloride of tin, at ioo° Tw 4 ozs. 
 
 No. 48. Scarlet. — 
 
 Cochineal liquor, at 12° Tw 2 gals. 
 
 Starch 4 lb s . 
 
 Boil, and add — 
 
 Oxalic acid 4 ozs. 
 
 Binoxalate of potash 4 » 
 
 Pink salts , 8 ,, 
 
 Tin crystals 8 „ 
 
 No. 49. Scarlet. — 
 
 Standard (see below) 3 gals. 
 
 Berry liquor, at io° Tw 1 quart 
 
 Starch 4$ lbs. 
 
 Boil, and add — 
 
 Binoxalate of potash ^ lb. 
 
 Oxalic acid j M 
 
 Pink salt ii lbs. 
 
 Tin, oxymuriate, at 120 Tw 1 pint. 
 
 No. 50. Scarlet Standard. — 
 
 Cochineal, ground 2 lbs. 
 
 Water 6 quarts 
 
 Red liquor, at 20 Tw 1 quart 
 
 Nitric acid 4 ozs. 
 
 Oxalic acid 2 ,, 
 
 Boil for twenty-five minutes, and strain off the clear for use. 
 No. 51. Yellow. — 
 
 Berry liquor, at 10° Tw 4 gals. 
 
 Starch 5i lbs. 
 
 British gum (pale) 1 lb. 
 
 Tin crystals i| lbs. 
 
 No. 52. Yellow (Lemon). — 
 
 Berry liquor, at 4 J° to 5 Tw 1 gal. 
 
 Gum 3 lbs. 
 
 Alum 8 ozs. 
 
 Oxalic acid i£ ,» 
 
 Perchloride of tin, at ioo° Tw 8 „ 
 
 623 
 
w; 
 
 624 DYEING AND CALICO PRINTING. 
 
 Woollen Goods. 
 Receipts for producing the usual colours on goods composed entirely of 
 wool may be conveniently given here. 
 
 No. 1. Black (Block).— 
 
 Calcined starch 10 lbs. 
 
 Logwood liquor, at 2 i° Tw 5* quarts 
 
 Water 14J ,, 
 
 Sapan liquor, at 20 Tw 1 J pints 
 
 Red liquor, at 10 Tw. 5 quarts 
 
 Nitrate of copper (crystals) 3 J lbs. 
 
 Nitrate of iron, at 80° Tw 2\ quarts 
 
 Iron liquor, at 14 Tw i\ ,, 
 
 No. 2. Black (Blotch). 
 
 Logwood liquor, at 6° Tw 9 quarts 
 
 Sapan liquor, at 6 Tw 9 ,, 
 
 Starch 2 j lbs. 
 
 Boil, and add before cooling — 
 
 Sulphate of copper f lb. 
 
 Sulphate of iron \ ,, 
 
 Extract of indigo -J „ 
 
 When cold add — 
 
 Nitrate of iron, at 8o° Tw ij lbs. 
 
 No. 3. Black (for French Merinos). — 
 
 Logwood liquor, at 10° Tw 6| quarts 
 
 Orchil liquor, at io° Tw. (blue shade) 2 ,, 
 
 Starch 2^ lbs. 
 
 Gall or myrobalan liquor, at 20 Tw J pint 
 
 Boil, and add — 
 
 Copperas 2 ozs. 
 
 Sulphate of copper 2 ,, 
 
 Extract of indigo 12 ,, 
 
 When cold add — 
 
 Nitrate of iron, at 80° Tw 15 „ 
 
 No. 4. Black (for Objects). — 
 
 Boiling water 1 gal. 
 
 S?.p?in liquor, n.t 2?° Tw. ... . , ... £ ., 
 
 Logwood liquor, at 48 Tw. 1 „ 
 
 Then add by degrees — 
 
 Water £ gal. 
 
 In which has been dissolved — 
 
 Bichromate | lb. 
 
 Thicken with — 
 
 Starch 3] lbs. 
 
 Gum-substitute 4 „ 
 
 Add while hot — 
 
 Sal-ammoniac ij lbs. 
 
 Verdigris 2\ „ 
 

WOOLLEN GOODS. 6e 5 
 
 When partially cool add — 
 
 Oxalic acid ij lbs. 
 
 Mix intimately with — 
 
 Oil of turpentine i P mt 
 
 When quite cold add — 
 
 Nitrate of iron, at go" Tw 3 J lbs. 
 
 Extract of indigo t,\ 
 
 No. 5. Black {both for Blotch and Objects). — 
 
 Logwood liquor, at 5 Tw 1 quart 
 
 Starch 4 zs. 
 
 Boil, and add when cold — 
 
 Nitrate of iron, at 8o° Tw 4 02s. 
 
 ' Nitrate of copper, at 8o° Tw 1 oz. 
 
 Gall liquor, at 5 Tw .' . . 5 ozs. 
 
 No. 6. Black. 
 
 Logwood liquor, at 5 J° Tw 1 quart 
 
 Gall liquor, at 8° Tw 1 gill 
 
 Orchil liquor 5 ozs. 
 
 Starch 6 ,, 
 
 Boil, and add while warm — 
 
 Extract of indigo 2$ ozs. 
 
 When cold add — 
 
 Nitrate of iron 7^ ozs. 
 
 No. 7. Blue, Dark. — 
 
 Starch 12 ozs. 
 
 Water 1 gal. 
 
 Boil, and while still hot work in — 
 
 Extradt of indigo ij lbs. 
 
 Tartaric acid 4 ozs. 
 
 Oxalic acid 6 ,, 
 
 Alum 10 ,, 
 
 No. 8. Blue, Dark {another shade). — 
 
 Extradt of indigo 9 ozs. 
 
 Alum 12 ,, 
 
 Oxalic acid 4i ,> 
 
 Cochineal liquor, at 6° Tw 7I ,, 
 
 Gum-water 1 J gals. 
 
 The depth of the shade can of course be easily modified by an increase or 
 decrease of the gum-water, and the blue can receive a bloomier tone, if re- 
 quired, by a slight increase of the cochineal. 
 
 No. 9. Blue, Royal. — 
 
 Oxalic acid* £ lb. 
 
 Alum 6£ ozs. 
 
 Water £ gal. 
 
 Gum 33 lbs. 
 
 2 s 
 

 626 DYEING AND CALICO PRINTING. 
 
 When cold add — 
 
 Perchloride of tin 4 ozs. 
 
 Red prussiate 20 ,, 
 
 Nitrate of iron, at 8o° Tw. 13 „ 
 
 No. 10. Brown, Maroon. — 
 
 Bark liquor, at 18° Tw 1 quart. 
 
 Cochineal liquor, at 5 Tw 1 ,, 
 
 Gum 1 lb. 
 
 Oxalic acid \ „ 
 
 Alum 3 ozs. 
 
 Bichloride of tin, at ioo° Tw 5 ,, 
 
 Extract of indigo ij ,, 
 
 No. II. Brown. — 
 
 Bark liquor, at 18° Tw 2\ gals. 
 
 Orchil liquor, at n° Tw 1 gal. 
 
 Cochineal liquor, at 6° Tw 1, \ gals. 
 
 Starch 4i lbs. 
 
 Boil and add — 
 
 Alum , 134 ozs. 
 
 Oxalic acid 84 ,, 
 
 Perchloride of tin 21 ,, 
 
 Extract of indigo 4* >> 
 
 No. 12. Brown. — 
 
 Berry liquor, at 18 Tw 1 quart. 
 
 Orchil liquor, at 18 Tw 1 ,, 
 
 Starch 1 lb. 
 
 Boil and add — 
 
 Alum 4 ozs. 
 
 Tartaric acid 2 ,, 
 
 Copperas 2 ,, 
 
 No. 13. Buff.— 
 
 Bark liquor, at 4 Tw 1 gal. 
 
 Orchil liquor, at 22 Tw. \ „ 
 
 Alum ij lbs. 
 
 No. 14. Chocolate, Dark. — 
 
 Orchil liquor, at 16 Tw. (blue) 1 J gals. 
 
 Alum 12 ozs. 
 
 Sal-ammoniac 2 „ 
 
 Oxalic acid 2 „ 
 
 Stir till the mixture ceases to froth, and add — 
 
 Starch 16J ozs. 
 
 Calcined starch 16.J ,, 
 
 And add — 
 
 Extract of indigo 6 ozs.. 
 
WOOLLEN GOODS. 627 
 
 No, 15. Chocolate, Medium. — 
 
 Orchil liquor, at 16 T\v 2 quarts. 
 
 Gum-water 2 „ 
 
 Extract of indigo 1 or. 
 
 No. 16. Chocolate, Reddish. — 
 
 Orchil liquor, at 16" T\v 1 gal. 
 
 Ammoniacal cochineal paste 7i ozs. 
 
 Alum 4 ,, 
 
 Oxalic acid 1 oz. 
 
 Sal-ammoniac 4 ozs. 
 
 Stir well till it ceases to froth, strain, and add — 
 
 Starch 1 lb. 
 
 Extract of indigo 3 ozs. 
 
 No. 17. Green, Dark. — 
 
 Bark liquor, at i7°'Tw 1^ gals. 
 
 Extract of indigo 3 lbs. 
 
 Sal-ammoniac 3 ozs. 
 
 Sulphate of alumina i.J lbs. 
 
 Dissolved in — 
 
 Water 3 pints. 
 
 Tartaric acid 10 ozs. 
 
 Oxalic acid 7 » 
 
 Cool down and add — 
 
 Perchloride of tin 10 ozs. 
 
 Yellow prussiate 4 ,, 
 
 Gum-substitute, according to the pattern. 
 
 No. 18. Green, Dark. — 
 
 Bark liquor, at 16° Tw 2 gals. 
 
 Extract of indigo ij lbs. 
 
 Alum 1 lb. 
 
 Gum, powdered 3 lbs. 
 
 1 1 eat and add — 
 
 Tartaric acid 8 ozs. 
 
 When cold add — 
 
 Oxalic acid 2 ozs. 
 
 Perchloride of tin, at 100° Tw i lb. 
 
 No. 19. Green, Lighter. — 
 
 Fustic yellow, at 12 Tw 1 gal. 
 
 Extract of indigo ^ lb. 
 
 Alum ii lbs. 
 
 Tartaric acid 6 ozs. 
 
 Oxalic acid 3 ,, 
 
 Gum-water 2 gals. 
 
 Perchloride of tin, at 100° Tw £ lb. 
 
 For the brightest greens, berry-liquor is generally employed as the yellow 
 constituent. Small amounts of cochineal liquor are occasionally added to give 
 more bloom and brightness to the blue constituent. 
 
 2 s 2 
 

 HHHM 
 
 628 DYEING AND CALICO PRINTING. 
 
 No. 20. Grey, Dark. — 
 
 Strong ammoniacal cochineal liquor ." 2 gals. 
 
 White tartar 1 lb. 
 
 Alum 8 ozs. 
 
 Extract of indigo 8 ,, 
 
 Berry liquor, at 7 T\v 1 J quarts 
 
 Thickening according to the pattern. For lighter shades reduce with gum- 
 water, and increase the proportion of the acids. 
 
 No. 21. Pearly Grey. — 
 
 Extract of indigo Jib. 
 
 Boiling water 6 gals. 
 
 Tartaric acid 2 lbs. 
 
 Alum 2 ,, 
 
 Ammoniacal cochineal paste i£ „ 
 
 Gum-water 8 gals. 
 
 Perchloride of tin, at ioo° Tw 1^ lbs. 
 
 No. 22. Grey, Dark. — 
 
 Logwood liquor, at 6° Tw 1 gal. 
 
 Nitrate of iron, at 80° Tw 10 ozs. 
 
 Gum-water 1 gal. 
 
 No. 23. Lilac.— 
 
 Ammoniacal cochineal liquor \ gal. 
 
 Acetic acid (weak) 1 quart. 
 
 Alum 10 ozs. 
 
 Oxalic acid 8 „ 
 
 Perchloride of tin 2 lbs. 
 
 Extract of indigo 6 ozs. 
 
 Gum-water 2 gals. 
 
 No. 24. Orange. — 
 
 Bark liquor, at 17 Tw 2 gals. 
 
 Cochineal liquor, at 3 Tw. 1 gal. 
 
 Gum 6{ lbs. 
 
 Oxalic acid 10 ozs. 
 
 Perchloride of tin 1 lb. 5 ozs. 
 
 No. 25. — Pink. — 
 
 Ammoniacal cochineal paste lib. 
 
 Cochineal in fine powder 1 ,, 
 
 Water 2 gals. 
 
 Boil down to ij gallons, and add — 
 
 Oxalic acid 6 ozs. 
 
 Perchloride of tin 12 ,, 
 
 Gum-water 2 gals. 
 
 No. 26. Yellow. — 
 
 Berry liquor, at n° Tw 1 gal. 
 
 Tin crystals 14 ozs. 
 
 Gum 5 lbs « 
 
WOOLLEN GOODS. 629 
 
 No. 27. Yellow. — 
 
 Bark liquor, at 18 Tw 1 gal. 
 
 Orchil liquor, at ii° Tw lib. 
 
 Alum 6 ozs. 
 
 Tartaric acid '. 2 ,, 
 
 Oxalic acid 2 ,, 
 
 Gum 3 lbs. 
 
 Perchloride of tin, at 108 Tw 6 oz. 
 
 No. 28. Orange-Yellow.— 
 
 Berry liquor, at 15 Tw 2 gals. 
 
 Starch 3 lbs. 
 
 Boil, and mix with — 
 
 Alum 1 J lbs. 
 
 Tin crystals 1 lb. 
 
 Oxalic acid 6 ozs. 
 
 (See p. 218). 
 
 No. 29. Black on Woollen Yarn. — 
 
 Extract of logwood (solid) 6 lbs. 
 
 Boiling water 10J pints. 
 
 Dissolve, let cool and settle, and add the clear liquid to — 
 
 Iron liquor, at 7° Tw 1 lb. 
 
 Nitrate of iron, at 88° Tw k ,, 
 
 Gum tragacanth £ „ 
 
 The amount of gum is subject to modification as the case may require. The 
 pieces, when printed, are exposed to the air for six hours, steamed for forty- 
 five minutes, rinsed, and dried. 
 
 No. 30. Drown on Woollen Yam. — 
 
 Extract of peachwood (solid) 2 lbs. 
 
 Extract of bark (solid) 1 lb. 
 
 Boiling water ioi pints. 
 
 Cool, let settle, and thicken with — 
 
 Gum tragacanth \ lb. 
 
 Red liquor, at 7° Tw i ,, 
 
 Mix thoroughly, and proceed as above. If a darker shade is required iron 
 liquor is added. 
 
 No. 31. Bismarck for Woollen Yam. — 
 
 Bismarck brown (according to shade) 1 oz. 
 
 Boiling water io| pints. 
 
 Cool, settle, and thicken with — 
 
 Gum tragacanth z\ ozs. 
 
 Starch 2i „ 
 
 Glue ? 1 \ „ 
 
 After printing, age for six hours and steam at 190 F. 
 
 No. 32. Ponceau for Woollen Yarn. — 
 
 Ground cochineal 1 lb. 
 
 Water 10J pints. 
 
630 DYEING AND CALICO PRINTING. 
 
 Boil and strain ; exhaust the residue with further portions of water, mix the 
 
 extrads, concentrate to ioj pints; cool and let settle. In the clear liquor 
 dissolve — 
 
 Oxalic acid 5 ozs. 
 
 Tin crystals 2i ,, 
 
 Thicken with — 
 
 Wheat starch £ lb. 
 
 White glue J „ 
 
 Print, steam at 190° F., and rinse. 
 
 No. 33. Scarlet for Woollen Yarn. — 
 The mixture is the same as for ponceau, but from \ to ij oz. of extrad of 
 fustic, previously dissolved in water, is added. 
 
 Silks. 
 There is in many cases a difficulty in preserving the whites — grounds or 
 figures — clean, as the silk has in itself a considerable attraction for colours. 
 Before the printing the goods are boiled for two hours with soap of a fine 
 quality, in the proportion of 1 lb. of soap to 4 lbs. of material. They are then 
 well rinsed in pure water, and dried. Every shade of colour can be produced 
 on silk by the steaming process, with the advantage that the grounds remain 
 unsullied. The goods are first prepared with tin, being steeped for four hours 
 in sulpho-muriate of tin, at 2° Tw. After this process the silk is washed in 
 clean water, and dried. 
 
 No. 1. Sulpho-Muriate of Tin, for Silks. — Dissolve in water — 
 Tin crystals 1 lb. 
 
 And add — 
 
 Sulphuric acid, at 170° Tw lib. 
 
 And reduce with water to 2° Tw. 
 
 No. 2. Blacks. — 
 
 Logwood liquor, at 8° Tw 2 gals. 
 
 Iron liquor, at io° Tw 1 quart. 
 
 Flour 1 lb. 
 
 British gum, light i„ 
 
 Boil, and add — 
 
 Yellow prussiate 6 ozs. 
 
 When cold add — 
 
 Sulphate of copper 2 ozs. 
 
 Muriate of iron, at 8o° Tw 1 pint. 
 
 Nitrate of iron, at 8o° Tw 1 gill. 
 
 No. 3. Black, for Grounds. — 
 
 Logwood liquor, at 8° Tw. 2 gals. 
 
 Acetate of copper (liquid), at 40 Tw 1 pint. 
 
 Red liquor, at 18 Tw 3202s. 
 
 Starch . . .... . , 2^ lbs. 
 
 Boil, and after cooling add — 
 
 Nitrate of iron, at 8o° Tw 14 ozs. 
 
SILKS. 631 
 
 No. 4. Black (Cylinder or Bldck). — 
 
 Logwood liquor, at 14 Tw 2 gals. 
 
 Starch i^ lbs. 
 
 British gum 3I „ 
 
 Boil, cool, and add — 
 
 Nitrate of copper (crystals) i^ lbs. 
 
 Nitrate of iron 1 lb. 
 
 No. 5. Black. — 
 
 Logwood liquor, at 6° Tw 2 gals. 
 
 Galls, in fine powder 7 ozs. 
 
 Boil down to 1 gallon, to which add — 
 
 Starch 1 lb. 10 ozs. 
 
 Boil, and when cold add — 
 
 Alum 2 ozs. 
 
 Sulphate of copper 6| ,, 
 
 Copperas 2 ,, 
 
 Nitrate of iron, at 8o° Tw 4i „ 
 
 Palm or cocoa-nut oil 5^,, 
 
 No. 6. Blue. — 
 
 Logwood liquor, at 15 Tw 1 gal. 
 
 Red liquor, at 15 Tw. 1 ,, 
 
 Ground gum 10 lbs. 
 
 When all is dissolved add — 
 
 Tartaric acid 10 ozs. 
 
 Nitrate of copper, at 8o° Tw 10 ,, 
 
 Extract of refined indigo 1 gal. 
 
 No. 7. Blue (Extract of Indigo). — 
 
 Extract of indigo (finest) 3 lbs. 
 
 Boiling water 1 gal. 
 
 Alum 8 ozs. 
 
 Tartaric acid 1 lb. 
 
 Gum 6 lbs. 
 
 No. 8. Royal Blue. — 
 
 Yellow prussiate 3 lbs. 
 
 Hot water 1 gal. 
 
 When dissolved add — 
 
 Tartaric acid i\ lbs. 
 
 When cold thicken with — 
 
 Gum, ground 7 lbs. 
 
 Add— 
 
 Perchloride of tin, at 8o B Tw i\ lbs. 
 
 These mixtures are to a great extent superseded by the aniline blues, which 
 produce the finest effects upon silk. 
 
632 DYEING AND CALICO PRINTING. 
 
 No. 8 a. Blue.— 
 
 Water i gal. 
 
 Yellow prussiate i lb. 
 
 Oxalic acid J „ 
 
 Tartaric acid £ ,, 
 
 Sulphuric acid, at 170-" Tw 2 ozs. 
 
 Gum Senegal water, at 6 lbs. per gal 1 gal. 
 
 No. 9. Brown. — 
 
 Berry liquor, at 6° Tw 1 pint. 
 
 Logwood liquor, at 3 C Tw 16 ozs. (measure). 
 
 Sapan liquor, at 3 Tw 3 quarts. 
 
 Starch 1 lb. 
 
 Alum . . * ,, 
 
 Nitrate of copper, at 8o° Tw \ „ 
 
 Perchloride of tin, at 8o° Tw £ ,, 
 
 If intended for block-printing, the starch is replaced by double its weight 
 of gum. This colour may be turned either on the yellow or the blue side by 
 increasing in the first case the proportion of berry liquor, and in the second 
 of logwood liquor. 
 No. 10. Brown. — 
 
 Berry liquor, at io£° Tw 2 gals. 
 
 Peachwood liquor, at 70 Tw ij ,, 
 
 Logwood liquor, at 7|° Tw 3 quarts 
 
 Alum z\ lbs. 
 
 Sulphate of copper ij „ 
 
 Gum, for thickening, about 8 ,, 
 
 Here, also, fine effects may be produced with the coal-tar browns. (See also 
 p. 209.) 
 
 No. if. Chocolate. — 
 
 Sapan liquor, at 12 Tw 2 gals. 
 
 Logwood liquor, at 12° Tw 5 quarts. 
 
 Bark liquor, at 16 Tw 1 quart. 
 
 Alum 2 lbs. 
 
 Sal-ammoniac i\ „ 
 
 Gum Senegal 14 ,» 
 
 No. 12. Chocolate (Heavy). — 
 
 Sapan liquor, at 20 Tw 2 gals. 
 
 Logwood liquor, at 20 Tw 2 quarts. 
 
 Alum 20 ozs. 
 
 Sal-ammoniac \ lb. 
 
 Verdigris lib. 
 
 Gum 10 lbs. 
 
 No. 13. Chocolate. — 
 
 Sapan liquor, at 5 Tw 2 gals. 
 
 Berry liquor, at io° Tw. .. J gal. 
 
 Logwood liquor, at 5 Tw 2 gals. 
 
 Starch 5 lbs. 
 
 Gum-substitute 8 ,, 
 
SILKS. 633 
 
 Boil, and add while still warm — 
 
 Alum 2 J lbs. 
 
 And when cold — 
 
 Sulphate of copper 1} lbs. 
 
 No. 14. Chocolate — 
 
 Sapan liquor, at 19 Tw 2 gals. 
 
 Berry liquor, at 17^ Tw. 2i ,, 
 
 Logwood liquor, at 19 Tw ij „ 
 
 Gum, ground 30.^ lbs. 
 
 Alum 4i i» 
 
 Sal-ammoniac 1 lb. 
 
 Verdigris i^ lbs. 
 
 No. 15. Green, Dark. — 
 
 Berry liquor, at 14J Tw 1 gal. 
 
 Gum 2 lbs. 
 
 After dissolving add — 
 
 Extract of indigo 71. ozs. 
 
 Tartaric acid solution, at 38 Tw 4 m 
 
 Permuriate of tin, at 8o° Tw 2 ,, 
 
 No. 16. Green. — 
 
 Yellow colour (see below, No. 26.) 1 gal. 
 
 Extract of refined indigo 1 gill. 
 
 Double muriate of tin, at 120 Tw. 2 J ozs. (measure.) 
 
 The most beautiful greens are now, however, obtained with the aniline 
 greens (aldehyd, iodine, or methyl), with additions of picric acid if yellower 
 tones are wanted (see p. 206). A good green may also be obtained by adding 
 to the blue colour No. 8 a, picric acid, more or less, according to shade. 
 
 No. 17. Grey, Dark. — 
 
 Logwood liquor, at 6° Tw 1 gal. 
 
 Nitrate of iron, at 8o° Tw \ lb. 
 
 Tartaric acid | oz. 
 
 Gum , 4 lbs. 
 
 No. 17 a. Orange. — 
 Make a solution of annatto by mixing — 
 
 Annatto 4 lbs. 
 
 Pearl-ash 10 ,, 
 
 Water 6 gals. 
 
 Boil this down to 3 gals. Run off the clear to 1 gal. Add — 
 
 Gum-water (at 6 lbs. per gal.) 1 gal. 
 
 No. ijb. Coralline Orange-Red. — 
 
 Coralline 2 kilos. 
 
 Soda at io° B., enough to dissolve; dilute with water ; add protochloride of 
 tin, at 40 B. ; heat afresh and filter. The lake thus obtained is mixed with — 
 
 Magnesia . . 100 grms. 
 
 Oxalic acid 260 ,, 
 
 Gum, in powder 2000 ,, 
 
 Water, enough to make up 10 litres. 
 
634 DYEING AND CALICO PRINTING. 
 
 Mix well, heat, and strain ; print and expose for ten hours before steaming for 
 thirty to forty minutes. 
 No. 18. Pink.— 
 
 Sapan liquor, at 6|° Tw i gal. 
 
 Gum, in powder 3 lbs. 
 
 Perchloride of tin, at 120° Tw 4 ozs. 
 
 No. ig. Pink. — 
 
 Ammoniacal cochineal liquor, at 6° Tw 2 quarts 
 
 Binoxalate of potash 3 ozs. 
 
 Perchloride of tin, at 120 Tw. i£ ,, 
 
 Gum water, at 6 lbs. per gallon 2 quarts 
 
 No. 20. Pink. — 
 
 Ammonical cochineal liquor, at 6° Tw 2 quarts 
 
 Alum 2 ozs. 
 
 Oxalic acid | oz. 
 
 Gum-water, at 6 lbs. per gallon 2 quarts 
 
 Saffranin yields the most beautiful pinks and light roses upon silk (see p. 207). 
 No. 21. Purple. — 
 
 Logwood liquor, at 3 Tw 1 gal. 
 
 Sapan liquor, at 3" Tw 1 ,, 
 
 Alum 4 lbs. 
 
 Acetate of lead (white) 3 ,, 
 
 Digest at a gentle heat for several hours with constant stirring. When the 
 alum is completely dissolved and the sediment has subsided draw off the clear 
 liquor. Of this take 2 quarts. 
 
 Gum-water, at 6 lbs. per gallon 2 quarts 
 
 Perchloride of tin, at 120 Tw 3 ozs. 
 
 Nitrate of alumina 1 oz. 
 
 Oxalic acid 1 ,, 
 
 For purple and violet shades the aniline colours, such as Hofmann's violets, 
 have a decided advantage (see p. 195.) 
 No. 22. Red. — 
 
 Cochineal liquor, at 4 Tw 3 gals. 
 
 Bark liquor, at 12° Tw 1 J pints 
 
 Starch 3 lbs. 
 
 Boil, and when cool add — 
 
 Oxalic acid 1 lb. 
 
 Tin crystals 1 ,, 
 
 No. 23. Red (Crimson Shade). — 
 
 Ammoniacal cochineal paste 2 lbs. 
 
 Water 1 gal. 
 
 Boil and strain ; then add — 
 
 Gum (ground) 2 lbs. 
 
 Alum 3 ozs. 
 
 Acetate of lead 2 ,, 
 
 Tartaric acid 1 oz. 
 
 Perchloride of tin 4 ozs. 
 
SPIRIT COLOURS. 635 
 
 No. 24. Scarlet. — 
 
 Cochineal liquor (strong) 3 gals. 
 
 Starch 2 lbs. 
 
 Boil and add — 
 
 Berry liquor, at 15 5 ozs. 
 
 Fustic liquor, at 15 4 „ 
 
 Binoxalate of potash 14 ,, 
 
 Tin crystals 2£ ,, 
 
 Perchloride of tin, at 100° T\v 10.J „ 
 
 No. 25. Yellow. — 
 
 Bark liquor, at 16 Tw 3 gals. 
 
 Alum Jib. 
 
 Tin crystals . . \J 3 ozs. 
 
 Oxalic acid 3d 
 
 Gum Senegal gibs. 
 
 No. 26. Yellow. — 
 
 Berry liquor, at 12 Tw 1 gal. 
 
 Alum 4 lb. 
 
 Tin crystals 8J ozs. 
 
 Gum 3 lbs. 
 
 No. 27. Yellow. — 
 
 Water 1 gal. 
 
 Turmeric ij lbs. 
 
 Berries .. x\ ,, 
 
 Boil down to 2 quarts, and add — 
 
 Tin crystals 2 ozs. 
 
 Alum .; lb. 
 
 Gum, according to shade, about 1 lb. 
 
 Ninth Style. — Spirit Colours. (Application Colours.) 
 Spirit colours are very brilliant, but not permanent. They derive their 
 name from the large proportion of " spirits," a technical name for acid solutions 
 of tin, which enters into their composition. Steaming is impracticable owing 
 to the great acidity of the mixtures; the printed pieces consequently are dried 
 at a gentle heat, exposed in the ageing room for a few hours, rinsed, washed 
 in cold water, and finally dried. 
 
 No. 1. Black. — 
 
 Logwood liquor, at 8° Tw 1 gal. 
 
 Water 1 ,, 
 
 Copperas 10 ozs. 
 
 Starch 3 lbs. 
 
 Boil and add — 
 
 Nitrate of iron, at 80" Tw 1 gill. 
 
 No. 2. Blue. — 
 
 Water 1 gal. 
 
 Starch ij lbs. 
 
SShBSI^H 
 
 636 DYEING AND CALICO PRINTING. 
 
 Boil and let cool down to 108 F., and add — 
 
 Tin pulp 1 quart 
 
 Pcrchloride of tin, at 120 Tvv 15 ozs. 
 
 No. 3. Blue. — 
 
 Water 1 gal. 
 
 Yellow prussiate 1 lb. 
 
 Alum 6 ozs. 
 
 Starch ij lbs. 
 
 Boil, and after cooling down to iro° F., add — 
 
 Nitrate of iron, at 8o° Tw 15 ozs. 
 
 Perchloride of tin, at 20 Tw 15 ,, 
 
 No. 4. Blue (Block).— 
 
 Water 1 gal. 
 
 Yellow prussiate 1 lb. 
 
 Starch i\ lbs. 
 
 Boil briskly for a few minutes, and when cool add — 
 
 Nitrate of iron, at 8o° Tw ii gills 
 
 Perchloride of tin, at 100° Tw 3 ,, 
 
 No. 5. Brown. — 
 
 Berry liquor, at 8° Tw 1 gal. 
 
 British gum (light) 2 lbs. 
 
 Boil, and add — 
 
 Tin crystals 1 lb. 
 
 Spirit pink (No. 10) 2 quarts 
 
 Spirit purple (No. 13) 2 ,, 
 
 No. 6. Chocolate. — 
 
 Spirit pink (No. 10) i\ gals. 
 
 Spirit blue (No. 3) 1 gal. 
 
 No. 7. Chocolate. — 
 
 Sapan liquor, at 8 5 Tw 3 quarts 
 
 Logwood liquor, at io° Tw 2 ,, 
 
 Bark liquor, at 13 Tw 1 quart 
 
 Starch 2 lbs. 
 
 Boil, and let cool down to no', and add — 
 
 Perchloride of tin, at ioo° Tw 1 pint 
 
 Nitrate of copper, at 8o° Tw % ,, 
 
 Oil 1 „ 
 
 No. 8. Green. — 
 
 Spirit blue (No. 3) 1 gal. 
 
 Spirit yellow (No. 15) 1 „ 
 
 No. 8a. Orange. — 
 
 Berry liquor, at 8" Tw 1 J gals. 
 
 British gum (light) 12 lbs. 
 
 Boil, and add — 
 
 Tin crystals 6 lbs. 
 
 Spirit pink (No. 10) 4 gals. 
 
J> 
 
 SPIRIT COLOURS. ' 637 
 
 No. 9. Pink. — 
 
 Sapan liquor, at 14 Tw 1 gal. 
 
 Sal-ammoniac \ lb. 
 
 Gum-water, at 6 lbs. per gal 1 gal. 
 
 Perchloride of tin, at 120 Tw 1 pint 
 
 No. 10. Pink. — 
 
 Sapan liquor, at 8' Tw 1 gal. 
 
 Water . ^ 1 ,, 
 
 Common salt 2 lbs. 
 
 Starch i£ ,, 
 
 Boil, and when cool add — 
 
 Perchloride of tin, at 120° Tw 1 pint 
 
 Nitrate of copper, at 80 Tw 3 ozs. (measure). 
 
 No. II. Pink. — 
 
 Peachwood liquor, at 8° Tw 1 gal. 
 
 Starch ij lbs. 
 
 Boil well together and add — 
 
 Nitrate of copper, at ioo° Tw \ gill 
 
 When cooled down to ioo° F. add — 
 
 Perchloride of tin, at 120 Tw 3 gills 
 
 Pink salt.. | lb. 
 
 Oil 1 gill 
 
 No. 12. Pink. — 
 
 Sapan liquor, at 8° Tw 1 gal. 
 
 Starch ij lbs. 
 
 Boil, and when cooled down to ioo° F., add — 
 
 Perchloride of tin, at 120 Tw 3 gills 
 
 Acetate of copper J gill 
 
 No. 12a. Pinks for Blocking Madder Work. — 
 
 Sapan liquor, at io° Tw 4! gals. 
 
 Pink salt 9 lbs. 
 
 Sal-ammoniac 3 „ 
 
 Sulphate of copper 2 ,, 
 
 Oxalic acid 5^ ozs. 
 
 Water 1 pint 
 
 Gum Senegal water (6 lbs. per gal.) 4J gals. 
 
 Perchloride of tin, at 120 Tw 1 J quarts 
 
 No. 13. Purple. — 
 
 Logwood liquor, at 8° Tw 1 gal. 
 
 Water 1 ,, 
 
 Copperas 10 ozs. 
 
 Starch 2 lbs. 
 
 Boil, and add — 
 
 Protochloride of iron, at 8o° Tw 1 pint 
 
 Perchloride of tin, at 120 Tw 1 ,, 
 
638 DYEING AND CALICO PRINTING. 
 
 No. 14. R<d. — 
 
 Sapan liquor, at 4 Tw 3 gals. 
 
 Sal-ammoniac 1 lb. 
 
 Verdigris 1 >. 
 
 Starch 4* lbs. 
 
 Boil, and when cool add — 
 
 Pink salt 5 lbs. 
 
 Oxalic acid lib. 
 
 No. 15. Yellow. — 
 
 Berry liquor, at io° T\v ipl. 
 
 Alum 8ozs. 
 
 Starch 1 lb. 
 
 Boil and aid — 
 
 Double muriate of tin, at 120° Tw 1 pint 
 
 Tenth Style. — Manganese Bronzes. 
 This style, formerly in great demand, is now almost obsolete. The goods 
 are padded in solutions of sulphate or chloride of manganese of varying 
 strength according to the shade required. For medium shades the solution 
 is about 8o° Tw. After padding the goods are dried and padded once in soda- 
 lye, at 24 Tw., and afterwards in a weaker lye, at 12° Tw. They are then 
 rinsed in water, and afterwards in bleaching lime, at 2 Tw. This operation 
 is continued till the pieces are perfectly brown all over. They are next 
 washed in water and dried. The colours printed on this brown discharge it 
 and are fixed in its place, thus producing blue, green, pink, yellow, &c, 
 designs on a brown ground. 
 No. 1. Blue. — 
 
 Water 6 gals. 
 
 Yellow prussiate 3I lbs. 
 
 Starch 10 lbs. 
 
 British gum, light 6 lbs. 
 
 Boil and add — 
 
 Tartaric acid 12 lbs. 
 
 Oxalic acid 6 ,, 
 
 Nitrate of iron l£ quarts. 
 
 Of this mixture 5 quarts are added to 3 quarts of double muriate of tin, at 
 120° Tw. 
 
 No. 2. Yellow (to be followed up with Chrome). — 
 
 Water 1 gal. 
 
 Nitrate of lead 5 lbs. 
 
 British gum, light 4 ,, 
 
 Boil, and add — 
 
 Tartaric acid 4 lbs. 
 
 Of this mixture 3 quarts are added to 1 quart double muriate of tin, at 120 Tw. 
 
 No. 3. Green. — 
 
 No. 1 (without the tin) . . . 2 quarts 
 
 No. 2 ( ,, ,, ) 1 quart 
 
 Double muriate, at 120 Tw 1 ,, 
 
PIGMENT PRINTING. 639 
 
 No. 4. Pink. — 
 
 Brazil-wood liquor, at 12 Tw 1 gal. 
 
 Sulphate of copper 2 ozs. 
 
 Sal-ammoniac 2 ,, 
 
 Starch , 2 lbs. 
 
 Boil, and add — 
 
 Perchloride of tin. at 120 Tw 8 ozs. measure. 
 
 Mix 2 quarts of this with 1 of double muriate, at 120 Tw. 
 
 No. 5. White— 
 
 Water 2 gals. 
 
 British gum, light 8 lbs. 
 
 Boil, and add — 
 
 Tartaric acid 8 lbs. 
 
 Double muriate of tin, at 120° Tw 1 gal. 
 
 No. 6. Black.— 
 
 Logwood liquor, at 8° Tw 1 gal. 
 
 Water 1 ,, 
 
 Copperas 10 ozs. 
 
 Starch 3 lbs. 
 
 Boil and add — 
 
 Nitrate of iron, at 8o° Tw 1 gill 
 
 When printed the gopds are allowed to hang for a few hours, then winced in 
 a free flow of water, then again in chalk water; next in water again, and next 
 in bichrome, at 40 Tw., in case of greens and yellows. Lastly, wash and 
 dry. 
 
 Eleventh Style. — Pigment Printing. 
 This style has in the last few years undergone a great development. When 
 first introduced, pigment colours had a heavy, opaque, dull effect, and were,, 
 besides, very liable to crack and peel off. These drawbacks have now been 
 overcome, and designs are now executed in this style which have all the light- 
 ness and brilliance of colours formed on or within the fibre, whilst in point of 
 solidity and permanence they leave little to be desired. 
 
 The first fixing agent selected was a solution of caoutchouc, in coal- 
 naphtha, which was worked up with the pigment to be applied to a proper 
 consistence. The naphtha was then driven off by the steaming-process, 
 when there remained the colour cemented to the cloth by a thin film of 
 caoutchouc. This process produced permanent results, but the evaporating 
 naphtha became the cause of frequent and serious accidents. A variety of 
 mixtures of drying oils and resinous matters — in fact varnishes — were also 
 tried. The effects were generally heavy, resembling a spot of oil paint 
 deposited upon the goods ; the oil was liable to spread, producing a grease 
 spot around the design, and the mixture not drying with sufficient rapidity, 
 smearing was a very common result. 
 
 The principal vehicles nowused for pigments are albumen, casein (lactarine), 
 and gluten. Concerning the preparation and properties of these organic 
 mordants information will be found in Chapter X., p. 80. 
 
 It must be remarked that the albumen of blood is coming more and more 
 into use as a substitute for egg-albumen. The separation of albumen from 
 
640 
 
 DYEING AND CALICO PRINTING. 
 
 
 blood is effected as follows : — The fresh blood is collected in circular, flat- 
 bottomed basins with perpendicular sides, 14 inches in diameter and 4 deep, 
 and containing about 2 gallons. In these the blood is let stand, without 
 stirring, for two to six hours until coagulated. Filters are provided similar 
 in form to the coagulating basins, but rather wider. Their bottoms and 
 sides are pierced with holes 2.J inches in diameter.' These filters are lined 
 with a dense, compact cotton or linen cloth. The serum is first decanted 
 into the filter. The filtered serum is received into a depositing vessel. This 
 has in its bottom a hole fitted with a cork through a perforation, in which a 
 glass tube slides up and down. As long as the serum is not perfectly clear 
 the upper mouth of this tube is kept above the level of the liquid, but when 
 all subsidence is at an end, which may be in twelve to fourteen hours, the 
 tube is drawn down so that its upper end comes below the level of the serum. 
 By gradual!)' sliding the tube downwards as required the serum, as far as 
 clear, may be drawn off with even less disturbance than by a syphon. The 
 clear serum is evaporated down to dryness at a very gentle heat, and may 
 serve instead of egg-albumen for fixing light and bright colours. 
 
 The clot is next thrown upon the filter and cut up into small pieces. The 
 coloured serum which runs through is not mixed with the clear, but is received 
 by itself into the subsiding vessel, and treated in the same manner as 
 described above. Its clearest portion is likewise evaporated to dryness, and 
 serves for fixing dark and heavy shades. The blood of five oxen yields 2 lbs. 
 of dry, colourless albumen. That of twenty sheep or thirty-four calves pro- 
 duces the same quantity. 
 
 The majority of the pigment colours used in this style have been already 
 described (see p. 150), but we have yet to notice certain brown and black 
 colouring matters. 
 Among these are — 
 
 Several metallic sulphurets. 
 
 Brown oxides and Vandyke brown. 
 
 Substances, such as Umber, Terra de Sienna, Cologne earth, &c. 
 
 Lampblack. 
 The black or brown metallic sulphurets have been occasionally applied to 
 tissues. Among the methods of fixing them may be mentioned the im- 
 pregnating of the tissue with a soluble metallic salt, precipitable by sul- 
 phuretted hydrogen. The pieces are first passed into a solution containing 
 solutions of lead, &c, and then are placed in an atmosphere of sulphuretted 
 hydrogen ; or the salts of such metals as lead, copper, mercury, cadmium, 
 mixed with hyposulphite of soda, are printed on the tissue, and die latter 
 steamed ; the hyposulphite becomes decomposed into sulphate, and a sulphide 
 of the metal is fixed. 
 
 Although lampblack is not used as a pigment to produce blacks, it is 
 occasionally employed for solid greys. The lampblack is, previously to use, 
 thoroughly purified by washing with caustic soda-lye to remove empyreumatic 
 matters, and is next generally mixed with its own weight of ultramarine to 
 obtain, by fixing with blood, a good grey ; or it may be used with ochre, ' 
 chrome-yellow, and other similar substances to produce various shades. 
 Lampblack grey resists strong chemical reagents. Its use is more general 
 
■a 
 
 i 
 
 / • 
 
PIGMENT AND OTHER STYLES. 
 
 €4.1 
 
 T 
 
 ,*.-"""'&::■ 
 
 ¥~r^* 
 
 
 Guignet's Green and Chrome Green, Chrome Black and Dichromate 
 
 of Lead. 
 
 abroad than in this country, for the reason that greys can be produced more 
 cheaply by other means. 
 
 A fine argentine effecl: may be produced by blocking in zinc powder 
 thickened with albumen. The pieces are then dried, steamed, and worked iri 
 a very neutral solution of protochloride of tin. The tin is thus reduced to 
 the metallic state, and deposited in place of the zinc. The goods are then 
 washed and well calendered to bring out the metallic lustre. The effecl: may be 
 varied by substituting for the chloride of tin a very neutral solution of nitrate 
 of copper, when that metal will be deposited instead of the zinc. 
 
 The three annexed specimens illustrate the pigment style in combination 
 with other styles. 
 
 gy'-iWA*"-" 
 
 Ultramarine Blue, Chrome Black, and Dichromate of Lead. 
 
 2 T 
 

 642 
 
 DYEING AND CALICO PRINTING. 
 
 The darker green is a mixture of chrome green (Guignet's) and aldehyd 
 green ; the pale green is chrome green alone. The black is composed of 
 loo-wood liquor, iron liquor, and red liquor. The orange is dichromate of 
 lead. The greens and orange are fixed with albumen thickened with gum 
 tragacanth. After printing the pieces are steamed for an hour. 
 
 The blues, dark and light, are ultramarine; the orange, dichromate of lead, 
 all fastened with albumen and thickened with gum tragacanth. The black is 
 chrome black, a mixture of logwood liquor, bark liquor, with chlorate of 
 potash as an oxidising agent, and chrome liquor (acetate of chrome) as a 
 mordant, and thickened with starch and gum. After printing the pieces are 
 steamed for an hour. 
 
 The dark and light purples are mixtures of ultramarine and vermillion ; and 
 the yellow is chrome, all mixed and fixed with albumen, and steamed after 
 printing. 
 
 I 
 
 3 
 
 m 
 
 '0 
 
 
 Ultramarine and Vermillion and Chrome. 
 
 The next two specimens show a combination of pigment colours with 
 madder-work. The blue in the first of these is ultramarine, the yellow a 
 chrome-yellow, and the green a chrome-green, fastened with albumen, and 
 subsequently steamed from thirty minutes to an hour. The black is a steam 
 chrome-black, consisting of logwood and bark liquors oxidised with chlorate 
 of potash, with acetate of chromium for a mordant, and thickened with 
 gum and starch. The red is extract of madder, applied in the usual manner 
 by printing on a mordant " colour " of acetate of alumina. 
 
 In the next pattern the slate colour is a pigment, carbonaceous grey, fixed 
 as above directed. The black, green, and yellow are produced in manners 
 similar to those in the preceding specimen, and the two shades of red are 
 also produced with extract of madder. The mordants, thickenings, and 
 manner of application are the samegfs those just described. 
 
& 
 
 PIGMENT AND OTHER STYLES. 
 
 643 
 
 Ultramarine and Madder Extract. 
 
 The pattern on p. 644 shows a combination of red, pink, orange, blue, green, 
 and black colours. The red and pink are again extract of madder, the 
 difference in depth of shade being produced by printing on mordants " colours " 
 of different strengths. The black is a steam-chrome black, whilst the 
 remainder of the colours, green, orange, and blue, are pigments mixed with 
 albumen and steamed after printing. 
 
 The first pattern on p. 645 shows similar colours upon a pale green ground. 
 The light and dark red, the deep green, the orange, the black, and the blue are 
 first of all produced by the methods recently described, printed, steamed, and 
 washed off. The entire piece is then "padded," that is printed all over with 
 a pale green colour and steamed again. This method of working impairs the 
 effect of the blue, red, and pink exceedingly little. 
 
 Carbonaceous Grey, with Chrome Black, Chrome Green, Chrome 
 Yellow, and Extract of Madder. 
 
 2T2 
 
644 
 
 DYEING AND CALICO PRINTING. 
 
 The second pattern on p. 645 shows the production of chrome-orange in light 
 and dark shades, not by means of a previously-prepared pigment, but by the 
 production of sub-chromate of lead in or upon the fibre itself. For a dark orange 
 the brown or grey sugar of lead thickened with starch is printed on, whilst for 
 a light orange a white sugar of lead is taken, and the thickening is gum. The 
 calico, before printing, is prepared with a solution of sulphate of soda or sulphate 
 of magnesia (Epsom salts). The thickened solution of sugar of lead is next 
 printed on ; after which the pieces are passed through a cold solution of sul- 
 phate of soda, and then through " sours " (very dilute sulphuric acid). They 
 are next washed and then "raised" in the so-called orange vat for three to 
 five minutes at a boiling heat. 
 
 The orange vat is made up with bichromate of potash, to which an excess 
 of caustic lime has been added. Caustic soda may be substituted for caustic 
 lime. The goods are next washed, and may then be passed through cold 
 lime-water to clear the whites. 
 
 \ '*. 
 
 Extract of Madder, Red and Pink, with Chrome Orange, Green, 
 Ultramarine Blue, and Chrome Black. (See p. 643.) 
 
 In addition to the receipts for aniline blacks, pp. 213 to 215, the following 
 may be useful : — Cordillot employs — 
 
 1. As Thickener. — 
 
 Wheat-starch , 10 kilos. 
 
 Water 24 litres. 
 
 Gum-water (1*2 kilos, per litre) 4 ,, 
 
 Tragacanth-water (65 grms. per litre) 6 ,, 
 
 2. /Is Oxidising Mixture. — 
 
 Thickener, No. 1 17 litres. 
 
 In which dissolve — 
 
 Chlorate of potash 900 grammes. 
 
 After cooling add — 
 
 Ferricyanide of ammonium 2 - 6 kilos. 
 

 PIGMENT AND OTHER STYLES. 
 
 645 
 
 Green Padded Ground, with Design in Madder, Red and Pink, Chrome 
 Orange, Green and Black. (See p. 643.) 
 
 3. Solution of the Aniline Salt. — 
 
 Of the above thickener 17 litres. 
 
 Hydrochlorate of aniline 2'4 kilos. 
 
 Tartaric acid 500 grms. 
 
 For printing, equal parts of the oxidising mixture and of the aniline solution 
 are mixed together. 
 
 Each of these mixtures can be preserved separately for a fortnight, but 
 when once mixed they cannot be kept for more than thirty hours. The goods 
 after printing are aged, washed, raised in a weak solution of chromate of 
 potash, and then passed through a weak soap bath. 
 
 Chrome Orange, Light and Dark. (Seep. 644.) 
 
646 
 
 DYEING AND CALICO PRINTING. 
 
 This mixture does not attack the doctors, but the black produced is less 
 intense than that obtained by Lightfoot's process, and the price is a little 
 higher. Cam. Kccchlin replaces the ferricyanide of ammonium by ferricyanide 
 of potassium and tartaric acid, and ages at a temperature of 50 to 6o° C. 
 Lauth uses the following mixture : — 
 
 Tragacanth mucilage i litre. 
 
 Torrified starch 650 grms. 
 
 Water 950 ,, 
 
 Chlorate of potash 150 ,, 
 
 Sal-ammoniac 50 „ 
 
 Hydrochlorate of aniline 400 „ 
 
 On the other hand he incorporates — 
 
 Wheat starch 500 grms. 
 
 Sulphide of copper 150 „ 
 
 Water 250 „ 
 
 When required for use the two are mixed together. The pieces are aged at 
 20 to 30 C. 
 
 The sulphide of copper is prepared by precipitating a solution of sulphate 
 of copper with sulphide of sodium. 
 
 Muller prepares a black for printing as follows : — Dissolve — 
 
 Water I litre. 
 
 Chlorate of potash 20 grms. 
 
 Sulphate of copper 30 ,, 
 
 Sal-ammoniac 16 „ 
 
 Hydrochlorate of aniline 40 „ 
 
 The mixture is heated in the water-bath to about 6o°. After two or three 
 minutes the solution swells, and readily boils over. If, after the lapse of 
 several hours, the thick mixture is not an intense black, it is once more heated 
 to 6o° C. The resulting paste is exposed for two days to the open air, then 
 washed on a filter long and carefully, until no more saline matter can be dis- 
 covered in the nitrate. A black of a more blue shade is obtained by using, as 
 "final wash-liquor, 1 litre of water in which 20 grms. of soluble aniline blue 
 have been dissolved. It is thickened with albumen, of which it requires a 
 lar^e quantity, printed, and well steamed. 
 
 Lightfoot's method of applying aniline black to animal fibre, or to mixed 
 fabrics, such as delaines, &c, is described as follows, in his Specification of 
 September 11th, 1S65 (No. 2327) : — " For mixed goods I wince or steep them 
 in a solution of hypochlorite of lime, — or a mixture of hypochlorite of lime, 
 hydrochloric acid, and water, — for the purpose of preventing the deoxidising 
 properties of the animal fibres and substances. When the wool or animal 
 substance is thoroughly oxidised to its maximum, and in a fit state to receive 
 the aniline black, it may be known by the following simple test : — Take a dilute 
 solution of permanganate of potash in two test-tubes, and into one put a piece 
 of the oxidised wool, and into the other a piece that has not been oxidised, 
 and apply a gentle heat ; the solution containing the one that is in a fit state 
 to receive the aniline black remains pinky, but the other is decolourised imme- 
 diately. The proportions for preparing the wool are about as follows : — I take 
 for every pound of cloth, wool, yarn, silk, delaine, feathers, or animal sub- 
 stance (well cleaned), 6 gallons of water at about 100° F., 2$ ounces by weight 
 
ANILINE BLACK. 
 
 647 
 
 of hydrochloric acid of commerce, and 1 pint of hypochlorite of lime in 
 solution containing 1 lb. of hypochlorite of lime to the gallon. I keep the 
 goods in this solution for from twenty to thirty minutes, or until the wool 
 becomes quite yellow ; I then wash well in water, and dry. The chlorodising 
 or oxidising sufficient for ordinary colours is not applicable to aniline black, 
 and a point of oxidisation or chlorodising is required which would not be 
 advisable to give to fabrics intended for ordinary colours. In dyeing coburgs 
 and similar goods the present processes involve two operations. I avoid this 
 twice dyeing by preparing the mixture of cotton, wool, silk, or other animal 
 substance, as above, so that they will both take a black dye at one and the 
 same time. I steep or pad the goods, either before or after drying, in the 
 following dye : — -i gallon of water, 4 ounces chlorate of potash, 12 ounces 
 chloride of aniline crystals, 6 ounces sal-ammoniac, 2 ounces sulphate of 
 copper. I then dry the goods at as low a heat as possible, and age for two or 
 three nights in a moist room at from 76 to 80° F., and when the colour is 
 
 r # # 
 
 Aniline-Black, with Madder-Red and Chrome-Orange. 
 
 thoroughly developed it becomes an intense myrtle-green, almost black. I 
 raise the goods either in water or any weak alkali, or in a weak cold solution 
 of neutral chromate of potash, which I use in preference; and if a brownish- 
 black is required, the goods may be subsequently dyed in a weak hot solution 
 1 of orchil or cudbear. When the prepared cloth is used for printing, I print on 
 1 the aniline black colour, as described in the Specification of my former Patent 
 ; already referred to, and dry and age in a warm moist room, and raise in weak 
 : alkali as before. I then pass the goods through a warm solution of sulphite 
 1 or hyposulphite of soda, or a solution of any suitable deoxidising agent, to 
 i improve the whites ; or the goods may be passed through Mr. Thorn's sul- 
 1 phuring apparatus. It is preferable after sulphuring to repass the goods 
 1 through a weak alkali." 
 
 The above pattern, printed by the late Mr. J. Lightfoot, of Accrington, is 
 ; an interesting specimen of the effects produced by combining aniline black 
 
648 DYEING AND CALICO PRINTING. 
 
 with other colours. It is obtained as follows : — For the red a mordant is used 
 composed of red liquor, at 12 Tw., thickened with 2} lbs. of flour per gallon. 
 Cool, and add per gallon 4 ozs. of muriate of tin crystals. 
 
 For the orange : — 
 
 Nitrate of lead 4$ lb«. 
 
 White sugar of lead 4z » 
 
 Water £ gal. 
 
 Dissolve, and add — 
 
 Gum Barbary, 6 lbs. per gallon ^ gal. 
 
 For the black: — 
 
 Sulphide of copper paste 1 gill (i.e. $ pt.) 
 
 Colour as below , . . 1 gal. 
 
 Mix just before printing. 
 
 To make the chlorate of ammonia : — 
 
 Tartaric acid 7 J lbs. 
 
 Boiling water 6 gals. 
 
 Dissolve, and add gradually — 
 
 Sesquicarbonate of ammonia 3 lbs. 2 ozs. 
 
 Mix gradually, and add — 
 
 Chlorate of potash 8 lbs. 
 
 Dissolve, and stir for ten minutes. Let stand till cold, and filter. Wash the 
 precipitated tartar with 6 quarts of cold water. This should yield 6 gallons 
 of clear chlorate of ammonia liquor. 
 
 To make the colour above referred to thicken this with British gum, 36 lbs. 
 (or a mixture of British gum and starch). Heat to 150° F., let stand till cold, 
 and add — 
 
 Aniline oil 4 quarts. 
 
 Best muriatic acid (34 Tw.) 3 ,, 
 
 Mix well together. 
 
 For the sulphide of copper : — # * 
 
 Flowers of sulphur 2 lbs. 2 fc^JT* 
 
 Caustic soda (70* Tw.) n| ,, # *" n i J 
 
 Stir well till dissolved without heat, and add it to — 
 
 Sulphate of copper 10 lbs. 
 
 Dissolved in — 
 
 Boiling water 20 gals. 
 
 Wash till neutral to test-paper, and filter till the bulk of the pulp is reduced 
 to 1 gallon. Print, and hang in a room at 70 F., with about 8 or 9 degrees 
 of difference between the wet- and dry-bulb thermometers. Age till black, 
 and pass through ammonia-gas. Hang in a cool room for a few hours, and 
 then pass through the following solution at 160 F. : — 
 
 Sulphate of soda 2 lbs. 
 
 Phosphate of soda 1 oz. 
 
 Water 1 gal. 
 
ANILINE BLACK. 649 
 
 Wash, and second dung twenty-five minutes at 130 F. 
 
 Water 100 gals. 
 
 Sulphate of soda 2 lbs. 
 
 Phosphate of soda 1 oz. 
 
 Solid cow-dung 4 quarts. 
 
 Wash, and dye with 13 lbs. madder per piece. Wash, pass through chloride 
 of lime at i° Tw,, then through steam-chest, and wash. Dry, and steam for 
 thirty minutes at 2 lbs. pressure. Wet, soap-wash, and pass through weak 
 sours (1 part of oil of vitriol, at 170 Tw.) to 1000 water, at 6o° F.) for six 
 minutes. Wash, and pass through chloride of lime as before. Wash, dry, 
 and raise orange in the usual way — first in bichrome alone, and then in 
 bichrome and lime at 212 F. Wash well, and pass through chloride of lime 
 as before. Wash and dry. 
 
 Paraf proposes the following process : — " Instead of using chloric acid 
 combined with potash I combine other bases which form salts more soluble or 
 less liable to crystallise, as soda, oxide of lead, barytes, strontian, lime, mag- 
 nesia, or similar bases. As the chloric acid of the chlorate ought to be set 
 free to enable it to oxidise, it will be easily perceived that I can liberate the 
 base more easily from the chlorates of barytes, lead, strontian, or lime, than 
 from chlorate of potash, by means of acids forming insoluble salts with the 
 bases herein named. I have already applied a reaction of potash to facilitate 
 the decomposition of chlorate of potash, and thus dispense \vith«a great part 
 of its defects. Instead of decomposing by the usual acids, —as oxalic, tartaric, 
 nitric, and similar acids, — I decompose by hydrofluosilicic acid, which gives a 
 salt of potash nearly insoluble, sets the chloric acid free, and prevents the 
 making of crystals. In consequence of the greater solubility of the chlorate, 
 and more complete setting at liberty of the chloric acid, I can put a larger 
 quantity in contact with the substances to be oxidised, and I obtain more 
 complete oxidation for steam-colours, such* as catechu and the aniline-blacks, 
 and similar colours. I obtain good results for aniline-black by using the 
 following proportions, which I will call ' black liquor '* : — 1 part chloride of 
 aniline, 1 part hydrofluosilicic acid at 6* Tw., and 10 per cent of protochloride 
 of iron dissolved in the aniline and acid. To save the greys the cloth is pre- 
 twxed,in a-solution of chlorate of soda, at 6° Tw. ; then print on the following 
 . afijodr: — 2 lbs. of aniline-black liquor, 3 lbs. of water, 2 lbs. white starch, 
 2 lbs. gum-dragon paste, 1 lb. brown British gum, 7 ozs. lamp-black. Boil 
 well together, and cool down. Age in a cold room for one or two days, but if 
 pressed for time the black can be produced in a few hours by running once or 
 twice through an ageing-machine. If saving the greys is no object the cloth 
 does not require any preparation, and the soluble chlorate can be given in the 
 colour and printed together upon the cloth. I use the following proportions : 
 — First, 2 lbs. black liquor, 3 lbs. water, 1 lb. starch, all well boiled together; 
 second, 6 lbs. chlorate of soda at 20 Tw., 2 lbs. starch, 2 lbs. brown gum 
 paste, 2 lbs. gum dragon. For the colour I use 1 part of the first mixture to 
 1 part of the second, and mix them cold. I can add, also, to a colour con- 
 taining a small quantity of chlorate of potash, other chlorates of greater 
 solubility than chlorate of potash, and the result will in all cases be better 
 
 * An ill-chosen name, since it already denotes the acetate orpyrolignite of iron. 
 

 650 DYEING AND CALICO PRINTING. 
 
 than with chlorate of potash alone. When I impregnate a fibre or pad fabrics 
 in a soluble chlorate which I dye in or print upon with a colouring matter to 
 be oxidised, as e.g. in the aniline black, when I want to secure the greys, I 
 can hasten the oxidation by adding to the colouring matter to be oxidised, or 
 in the aniline black colour, 2 or 3 per cent of a salt of oxide of iron, copper, 
 chrome, or manganese. I also use chloric acid, combined with aniline or its 
 homologues, for the production of black or grey colours. I decompose 
 sulphate, oxalate of aniline, or similar salts, with chlorate of barytes, lead, 
 lime, strontian, so as to produce by double decomposition chlorate of aniline 
 or its homologues, which, printed or dyed upon fabrics or yarns, produces fast 
 blacks or greys by ageing; and in this case I find also an advantage in adding 
 to the aniline 2 or 3 per cent of a salt of iron, copper, chrome, or manganese. 
 Animal matters do not take easily colours formed by oxidation. I surmount 
 this difficulty by fixing in the fibre metallic oxides, such as copper, alone or 
 combined with chrome, and then the animal matter takes aniline black 
 colours. I find an advantage in preparing the animal matters which have to 
 be dyed or printed with aniline black in the following mixture: — 1 lb. sulphate 
 of copper, i lb. chlorate of soda, £ lb. bichromate of potash, and 1 gallon of 
 water." — (Specification No. 2859, November 6, 1865). 
 
 In another patent the same chemist recommends the use of — " Insoluble 
 binoxide of chromium, or insoluble or soluble chromate salts capable of 
 evolving chromic acid, either slowly, in the presence of water or certain acids 
 or alkalies, or simply by ageing or steaming; and I find it of great use in the 
 production of aniline and its homologous black or grey colours, in which I mix 
 a salt of aniline and the brown binoxide of chromium, either alone or in con- 
 junction with a chlorate, and such mixtures printed upon cloth produce fast 
 aniline black by ageing. The following proportions have given me very good 
 results : — First, 12 ozs. chloride of aniline, 3 lbs. of water, and 1 lb. of starch, 
 boiled together; secondly, 8 ozs. # of brown binoxide of chromium in paste, 
 and 4 ozs. of chlorate (of what base the patentee does not state), to 1 gallon 
 of thickening. The colour for printing is a mixture of equal parts of these 
 two compositions. If I want to dye or print very heavy objects, I can easily 
 produce the necessary quantity of binoxide of chromium in the fibre by padding 
 or dyeing first in a solution of a sulphate or chloride of chromium, and then 
 passing the goods through a solution of monochromate of potash ; then dye 
 in a salt of aniline. The chlorate hastens the production of the colour, but 
 the binoxide of chromium and the salt of aniline can be used alone, and give 
 very good blacks ; but in this I find an advantage in introducing in the colour 
 from 3 to 5 per cent of arsenic acid, which in this case assists the decompo- 
 sition of the binoxide of chromium." — (Specification No. 1174, April 26, 
 1866). 
 
 Murexide Purples. 
 
 Like the aniline blacks, the murexide shades do not fall naturally under any 
 of the above great styles. Upon cotton the following formula gives a deep 
 shade : — 
 
 Gum-water 1 litre. 
 
 Nitrate of lead 400 grms. 
 
 Crystalline murexide 1 grm. 
 
ACCESSORY OPERATIONS. 651 
 
 For light shades dilute the above with gum-water containing 100 grms. nitrate 
 of lead per litre. After printing, the goods are hung up for a few hours in 
 moist air. They are then passed, for a minute or half a rtinute, into a chest, 
 the air of which is strongly impregnated with ammonia, and next passed into 
 a bath containing 2-5 kilos, of corrosive sublimate per 1000 litres of water. 
 Here they are left for twenty minutes, then washed in flowing water, and 
 passed anew into a bath containing — 
 
 Corrosive sublimate 1 kilo. 
 
 Acetic acid, at 7 to 8° Baume 1 ,, 
 
 Acetate of soda 500 grms. 
 
 Wash, and dry. If the pieces, after drying, are passed through a weak alkaline 
 bath, the colour becomes more violet. 
 
 Operations Accessory to Dyeing. 
 
 Although the process of bleaching has been described in an earlier portion 
 of this work (see pp. 44 and 87), there are a variety of subsidiary operations, 
 both before and after dyeing, in the strict sense of the term, which require 
 explanation. As a preliminary, it will be needful to glance briefly at the 
 different states in which textile materials are submitted to dyeing, and which 
 have been only incidentally mentioned. 
 
 Cotton is very rarely dyed in the 11 n spun state, as cotton-wool. It is chiefly 
 dyed as yarn or spun thread, either in the hank or — in some cases — in the cop. 
 The latter process, where practicable, is economical, as saving the time and 
 labour required for forming the yarn into hanks; but to cause the mordants 
 and dye-liquors to penetrate through a compact cop, so that the colour pro- 
 duced may be full and even, is very difficult. Cotton is comparatively rarely 
 dyed in the woven state. Wool is operated upon by the dyer in a greater 
 number of states. Very large quantities are dyed in the original, unspun, 
 state : this is the case with the wool intended to be worked up into superior 
 qualities of broadcloth. The dye, under these circumstances, has full facility 
 for acting thoroughly upon every fibre : hence wool-dyed colours are generally 
 considered the fastest, and the goods, other things being equal, fetch a higher 
 price than such as are dyed in the piece. In consequence, stratagems have 
 been devised for giving to piece-dyed doe-skins, &c, the appearance of having 
 been dyed in the wool. In piece-dyed goods the listings are, naturally, of the 
 same colour as is the body of the piece. If, however, there be applied to the 
 listings some solution which may discharge the dye, and leave them either 
 white or of a shade differing from that of the body of the piece, purchasers 
 are led to suppose that the cloth has been dyed in the wool. 
 
 Wool-dyeing, besides superior fastness and penetration, has the advantage 
 in evenness. Should any slight inequality, either of depth or of tone, occur, 
 yet when the whole of the wool has been " scribbled " together such defects 
 disappear, and the surface of the woven cloth will be found to exhibit a colour 
 absolutely alike in all parts. To counterbalance these advantages great care 
 is required that the pieces may not become soiled in any of the operations 
 subsequent to dyeing. The chief practical difficulty in wool-dyeing is to pre- 
 vent the mass from becoming felted together, so as to be unfit for carding and 
 spinning. In wool-dyeing care should also be taken to present the wares in a 
 suitable form. If ground or chipped dye-woods, orchil-paste, &c, are used, 
 

 >52 
 
 DYEING AND CALICO PRINTING. 
 
 the fragments become entangled among the wool, and can only be removed — 
 if at all — by very tedious washing. Hence the woods, &c, should be applied 
 in the state of liquid extracts. 
 
 A further very large quantity of wool* is dyed in the state of yarn. Almost 
 all the wool used in carpets, hosiery, shawls, table-covers, dress-pieces, and 
 all those goods in which the Jacquard loom shows itself a formidable rival to 
 the printing-machine, is yarn-dyed. Wool is sometimes also dyed in the state 
 of " slubbings " or "slivers." These are long masses of wool, which, by 
 drawing out and twisting, become converted into yarn ; they require, in 
 dyeing, the same precautions as loose wool. Piece-dyeing holds a very pro- 
 minent position as regards woollen and worsted goods. By far the greater 
 part of stuffs, whether consisting of " all wool " or of a worsted weft and 
 cotton warp, are dyed in the piece. So, likewise, is the bulk of the cloth made 
 in the present day. The piece-dyer has certain peculiar difficulties to en- 
 counter : the first of these is the possibility of the dye attaching itself more 
 strongly to one part of the surface of the cloth than to another. If this once 
 takes place the piece has a more or less cloudy or spotty appearance, which is 
 very difficult to remove, and which cannot exist without at once betraying 
 itself. There is especial danger of this unevenness with dyes which have a 
 very powerful affinity for the fibre, and which are consequently apt to seize 
 hold, in excess, of the first portion of the piece that enters the dye-beck. To 
 prevent or lessen this tendency certain substances are used called levellers. 
 One of these is sulphate of soda, Glauber's salt, or sal-enixum, called by 
 many dyers Sally Nixon. This salt is added to many dye-mixtures, and 
 seems to lessen the affinity of the colour for the cloth to such a degree that — 
 instead of being rapidly and irregularly deposited upon the surface — it inter- 
 penetrates the whole equally, and produces an even or " level " shade. 
 
 With the aniline colours the risk of irregularity is very great, especially on 
 goods woven from fine, soft wools. If any particles of the dye have escaped 
 perfect solution, and remain suspended in the beck, — if the methylated spirit 
 frequently used as a solvent has partially evaporated, leaving some of the 
 colour in the form of a bronzy scum on the surface, — or if the liquid has been 
 worked up into a froth or " flurry " by the rapid passage of the pieces through 
 the beck, — spots and stains are almost inevitable. To prevent these incon- 
 veniences glycerin may be used in dissolving the dye, or may be subsequently 
 added to the bath. It does not allow the colour to separate out, and prevents 
 bronzing and " flurry." With magenta, small quantities of white soap are 
 used by some dyers — an addition which levels the colour, and gives a slightly 
 iedder tone. A decoction of Panama bark (Quillaja safionaria) is sometimes 
 added to the dye-beck, with good effect, for the same purpose. Pieces spotted 
 and stained, " flushed " with aniline colours, may be considerably improved 
 by being winced in this decoction. 
 
 Panama bark is also used for another purpose, which it may not be out of 
 place to mention here. If it is desired to produce upon woollen or worsted 
 goods the purest and most lustrous whiteness, — whether for sale in that state 
 as " double-stove whites," or for being dyed particularly light and brilliant 
 shades, such as light roses, light greens, peaches, pale violets and blues, &c, 
 
 * The distinction between wool and worsted is, from a tinctorial point of view, unimportant. 
 
ACCESSORY OPERATIONS. 
 
 653 
 
 — after being repeatedly sulphured (see p. 88) and washed in the usual manner, 
 the fabric receives a final washing in the decoction of Panama bark, which 
 leaves it more lustrous to the eye, and softer and more kindly to the touch 
 than the best-balanced and most emollient soap. Some good practical 
 authorities maintain that where quality is of more importance than cheapness 
 the process of sulphuring should be performed,— not with the fumes of burning 
 sulphur, but with a solution of the bisulphite of soda (leucogene), or, better 
 still, bisulphite of magnesia. As to the mordanting power ascribed to these 
 bisulphites, further experiments are wanting. 
 
 Returning to the prevention of irregularity in piece-dyeing, in case of 
 colours whose affinity for the fibre is very strong, it is often found prudent to 
 dissolve at the outset merely a part of the dye needed to bring up the goods 
 to the shade required, and to add the rest by degrees. A good mechanical 
 precaution to ensure a level shade is to wince the pieces at first with great 
 swiftness. The wetting the pieces with water previous to dyeing is also a 
 point of importance. If any portions of the goods have escaped being tho- 
 roughly moistened, or if they are in the least degree greasy, soiled, or abraded, 
 irregularity is certain. 
 
 Another essential point in piece-dyeing is thorough penetration of the 
 colour, so that, if a small portion be torn or cut off, the section or tear may 
 bring to light no undyed filaments. If the cloth is not dyed through and 
 through it will, after a little wear, begin to exhibit a greyish reflection, and 
 complaints will reach the dyer that his colours " wear off." Cloth that is not 
 dyed through generally displays a correlative fault ; the colour is deposited 
 loosely on the outside, — " plastered on," as it is technically called, and is 
 hence deficient in lustre. 
 
 Rag-dyeing is a branch requiring more skill and judgment than the outside 
 public are aware. Woollen clippings and rags, after some rough sorting as 
 regards colour, are re- dyed preparatory to being converted into shoddy and re- 
 manufactured. As these rags have been dyed before, the production of the 
 new shade required is attended by the discharge or alteration of the old. 
 From the nature of the case it is important that these changes should be 
 effected with the smallest possible outlay in wares. To take a very simple 
 case — the conversion of black rags, dyed with an iron mordant and logwood, 
 into claret. To strip the black dye from the rags, rendering them white or 
 nearly so, and to produce upon them a claret shade, as would be done upon new 
 material, would be tedious and costly ; but the end is gained simply by boiling 
 the black rags with water to which a suitable proportion of claret spirit (p. 526) 
 — a preparation of tin — has been added. On the fibre is a black compound of 
 oxide of iron and of the colouring matter of logwood. The chloride of tin 
 attacks the iron, and removes it by reason of its superior affinity at once for 
 the wool and the colouring matter. What remains on the fibre is then a 
 claret-coloured compound of oxide of tin with the logwood. Thus the re-dyeing 
 is effected without the use of any fresh dye-ware, one mordant having been 
 merely substituted for another. Evenness of colour is not insisted on in case 
 of rag-dyeing, since, when the material has been torn up into shoddy, all its 
 irregularities disappear. 
 
 The re-dyeing of worn garments (job-dyeing) may be classed with piece- 
 dyeing, and offers all the especial difficulties of the latter, heightened by the 
 
654 
 
 DYEING AND CALICO PRINTING. 
 
 circumstance that the irregular abrasion of different parts of its surface renders 
 the attainment of a really level shade impossible. 
 
 One of the subsidiary operations applied to stuffs about to be dyed in -.he 
 piece is singeing. The object of this process is the entire removal of all 
 roughnesses and projecting fibres, so that the stuff may exhibit a perfectly 
 smooth surface. This can only be effected by a rapid combustion, so perfectly 
 under control that the down may be entirely burnt away without the bod} of 
 the tissue being in the slightest degree weakened or discoloured. This was 
 formerly done by passing the goods with great velocity over a convex plate of 
 cast-iron, heated to a very high temperature. It is now executed, in preference, 
 by the aid of burning coal-gas. One of the best arrangements for this is 
 Tulpin's singeing-machine (PI. VIII.). The use of gas was at first grealy 
 restricted, in consequence of a defect which seemed insurmountable. As -.he 
 pieces moved above the points of the flames which burnt the down, the acton 
 was not sufficiently limited to the surface, but extended to the filaments in .lie 
 interior of the tissue, which was thus rendered thinner, and its value was 
 reduced. Tulpin remedies this defect by employing, not the point of .he 
 flame, but its lateral part, along which he causes the stuffs to graze. His 
 machine is so contrived that the operation can, at will, be repeated twice on 
 each side. The steadiness of the flame is secured by means of a ventilator 
 which draws off the produ&s of combustion. A smaller ventilator sends in 
 air, and mixes it with the coal-gas in sufficient proportion to produce a blue 
 flame as in the Bunsen burner, giving out heat rather than light, and com- 
 pletely free from smoke. In this manner the danger of staining or blacken. ng 
 the pieces is completely obviated. This singeing-machine may be advanta- 
 geously used in preparing calico for printing. 
 
 Another important operation is " crabbing." Before stuffs can be dyed, all 
 dirt, grease, and the dressing used by the weaver, must be completely removed. 
 The pieces are generally first passed through hot water, to dissolve and remove 
 size or stiffening. They are next treated with hot lyes of soap, carbonate of 
 soda, and liquid ammonia, to remove all fatty and resinous matters. Every 
 trace of soap and alkali is finally washed out, by rinsing in abundance of 
 water. The apparatus used resembles that figured on p. 306 (Fig. 22). 
 
 The manipulation — " working or turning " — during the act of dyeing itself 
 is conducted in different manners, according to the nature of the goods. In 
 wool- and rag-dyeing the dyer's pole is still employed to turn the material 
 operated upon ; but in piece-dyeing there is fixed over every beck or cistern a 
 roller or wince, which can be turned by hand, or, as is more common in large 
 modern establishments, by steam- or water-power. Round this roller the 
 pieces are wound, and, as it revolves, they are alternately let down into the 
 liquid and drawn out again, the dyer taking care that they do not get entangled, 
 — which sometimes happens with thin goods, — and that they coil and uncoil 
 evenly. 
 
 After the completion of the dyeing — properly so-called — the pieces are, as a 
 rule, saturated with an excess of uncombined colouring matter, from which 
 they require to be freed by copious washing. This was formerly effected by 
 suspending the goods in a clear running stream. Since in manufacturing 
 districts the rivers are now more adapted to soil than to cleanse anything, 
 this primitive method of washing has given place to mechanical arrangements 
 
INFLUENCE OF LIGHT UPON COLOURS. 
 
 655 
 
 such as that represented in PI. IX. The pieces, on leaving the dye-beck, enter 
 a large tank of water, where they are well agitated : hence they pass between 
 two cylinders under a torrent of water discharged upon them from above ; 
 they next descend into a narrower tank, into which water falls from a wide 
 pipe ; they are then passed between a second pair of cylinders, still exposed 
 to a copious descending shower of water. 
 
 The process of drying is conducted in various manners, according to the 
 nature of the goods. Cloth is generally stretched out on " tenters " (extenders) 
 in the open air, or in large sheds heated by steam-pipes. Certain colours very 
 susceptible to the action of light, such as safflower shades on any kind of 
 material, are best dried in the dark, by means of a current of cold air driven 
 over them by means of a fan. Worsted and mixed stuffs, such as merinos, 
 coburgs, delaines, &c, are dried by passing over rollers heated by steam, as 
 shown in PI. X. 
 
 With the modern rage for apparent cheapness the process of finishing has 
 grown in importance. Goods, both white and coloured, depend to a great 
 extent for their appearance, and even for their body, not so much upon textile 
 fibres — whether animal or vegetable — as upon a variety of dressings, finishings, 
 and weightings, for which the wool or cotton serves merely as a kind of frame- 
 work. Gums, Iceland moss, starches, glue, sulphates of lime and baryta, 
 Epsom salts, and chloride of magnesium, dexterously mixed and introduced, 
 hide a multitude of deficiencies, and convert a weak, straggling, canvass-like 
 network into a smooth, full, and compact article — until it has paid its first 
 visit to the wash-tub, when the truth is revealed. These additions are made 
 most largely to cotton goods : woollen cloths are weighted to some extent 
 with the chloride of magnesium, which — from its high specific gravity, its 
 power of attracting moisture from the air, and its want of action upon colours 
 — receives the preference. 
 
 Stuffs, previous to finishing, are moistened with an extremely fine shower, 
 produced by allowing water to descend through a sieve of silk. They are then 
 passed over the finishing-machine shown in PI. XI., consisting of three 
 hollow cylinders, the temperature of which can be rapidly raised or lowered. 
 This operation requires a very considerable amount of skill and experience on 
 the part of the workmen, and on its correct execution the appearance of the 
 goods greatly depends. The last process to which stuffs are subjected in dye- 
 works is hot-pressing. Between each fold of the piece is placed a layer of a 
 smooth, elastic paper, made expressly for this purpose. At certain intervals 
 plates of cast-iron, strongly heated, are inserted, and the whole is submitted 
 to the action of the hydraulic press. 
 
 Influence of Light upon Colours. 
 In its action upon colours light has been compared to the Indian Trimurti, 
 combining the triple functions of generator, modifier, and destroyer. In 
 darkness we are told organic colours are not produced, whilst the more intense 
 the light the more brilliant and varied are the hues developed. In support 
 of this view a great body of facts may be brought forward. That the flowers, 
 the fruits, the insects of tropical regions are more richly coloured than those 
 of climates where the sun has less power is a truism. If we argue that the 
 colours thus produced may be due, wholly or partially, to the higher 
 

 
 6s6 
 
 DYEING AND CALICO PRINTING. 
 
 temperature of the torrid zone, we are met with the following phenomena: — 
 The leaves and flowers of plants kept in dark places are pale and bleached in 
 appearance, irrespective of the temperature to which they are exposed, as, for 
 instance, the shoots of a potato kept in a dark cellar. The diurnal Lepidoptera 
 of all countries are much more splendid than the nocturnal species of the 
 same districts. The under surface of the wings of butterflies is often as gaily 
 coloured as the upper. But it is as nearly as much exposed to light, both 
 when the insect is flying and when it is in a state of repose. In moths, on 
 the other hand, when the under surface is very little exposed to light, its 
 colours are sombre and monotonous. Nocturnal beetles of the Lamellicorn 
 order, such as the Geotrupidas, exhibit dull and dark shades, whilst the 
 Cetoniads, the diurnal members of the same order, might be characterised as 
 animated jewels. Among birds and mammals the same general rule prevails ; 
 those of sunny climates are brighter than those of cold and gloomy countries ; 
 diurnal species are more gaily clad than the nocturnal, and in one and the 
 same species the parts most exposed to light — the head, back, and shoulders 
 — are more highly coloured than the belly, and, in birds, the sides where 
 covered by the wings. The difference in appearance between the sunny and 
 the shady side of a peach or an apple is well known, as also the circumstance 
 that the stems of plants, green above the surface of the soil where fully ex- 
 posed to light, are pale or colourless below, where the light is excluded. On 
 the faith of these, and similar phenomena which do not require to be 
 individually enumerated, the colouration of organic bodies is generally con- 
 sidered to be a direct result of light, increasing in depth and brilliance with 
 its intensity, and fading away in its absence. 
 
 But there are, on the other hand, indisputable facts which must tend to 
 modify this conclusion. In the vegetable world we find roots completely 
 excluded, of course, from the light during the whole life of the plant, and yet 
 coloured or even containing powerful colouring matters. As common 
 examples we may cite the carrot, the Eschscholtzia, and madder, with its 
 congeners. It has been often pointed out that that the timber of trees 
 growing in cold climates is pale, whilst in the torrid zone deep colours are 
 generated, as in the dye-woods, ebony, and others. But the heart-wood of a 
 tree is certainly not exposed to any direct action of the solar rays. In the 
 animal world it must be remarked that subterranean and nocturnal species 
 cannot be indiscriminately pronounced to be pale, bleached, or etiolated. On 
 the contrary, many of them, such as the Harpalid and Geotrupid beetles, 
 certain spiders, &c, exhibit intense colours, such as deep browns or blacks. 
 The common badger presents a striking exception to the rule that the upper 
 or sunny side of animals is more deeply coloured than the belly. Two genera 
 of moths, the Arctias and Catocalas, display colours as gorgeous as any 
 butterfly— scarlet, crimson, rose, and blue. Yet these colours are almost con- 
 fined to the hinder wings, which are completely and closely covered by the 
 anterior pair when the insect is at rest, and are only unfolded on the night air 
 when it is flying. Perhaps the most nocturnal quadrupeds are the Felidce, yet 
 amongst them we find some of the most gaily coloured species of mammalians. 
 Again, though plants allowed to grow in darkness are devoid of their natural 
 colours, animals do not, under the same circumstances, undergo a correspondi ng 
 change. This has been proved by direct experiment. ^Caterpillars of Vanessa Io 
 
ACTION OF LIGHT. 
 
 657 
 
 have been reared up in darkness, but when matured and transformed into 
 butterflies they exhibited the usual colours of their species in undiminished 
 brilliance. Nay, in the common course of nature, many insects pass their 
 period of development in perfect darkness, and then suddenly emerge in the 
 full splendour of their mature state. This, for instance, is the case with the 
 Buprestids, with the Longicornes, the Curculionides, including the gorgeous 
 diamond beetle. How, then, can it be contended that the colouration 
 of such species is, in any direct manner, the work of light ? If we found that 
 the larvae of brilliant insects were, as a rule, more exposed to light than those 
 of dull and sombre species, or if, when arrived at maturity, the development 
 of their colours were at all dependent upon the amount of light which they 
 encountered, we might then entertain a different opinion. 
 
 With artificial colours and dyes the action of light is also very doubtful. 
 Let us take the case of rosanilin : it will scarcely be conceded that this dye 
 was pre-existent in the wood or other vegetable matter from which the coal 
 originated. In its subsequent career in the mine, in the gas-works, and in 
 the colour manufactory its exposure to light has been trifling indeed. Nor do 
 any facts seem to indicate that either the quality of the aniline colours would 
 be improved or the yield increased by the action of light during the various 
 stages of its manufacture. We cannot, therefore, pronounce light to be 
 exclusively or pre-eminently the direct colour-generating force; although that it 
 indirectly promotes the development of colours in organic beings is extremely 
 probable. 
 
 As a modifier and destroyer of colours the action of light is very manifest. 
 Very few colours, natural or artificial, can be long exposed to direct sunlight 
 without undergoing some degree of change, which may vary from a slight 
 alteration of tone to total discharging. Every stage of this action may be seen in 
 the vegetable world. Certain flowers, such as the wild rose, the blackberry, and 
 nut-blossom, the wood-sorrel and the wood-anemone, are perfectly bleached 
 by a few hours' exposure to sunshine. In other cases there is either a change 
 from red to blue or from blue towards red. The former variation can be seen 
 in the flowers of the mountain-heath (£. cinerea), which when overblown pass 
 from their original rose to a violet. The second, or inverse, change may be 
 seen in the corolla of many varieties of fuchsia, which is of a blue-violet 
 shade when the flower first opens, but becomes redder and redder the longer 
 it is exposed to the light. The changing colouration of the leaves of trees, 
 as it gradually passes from the pale but bright tones prevalent in spring, to 
 the full, deep greens of summer, and thence to the maroon, orange, yellow, 
 and brown of autumn, is due in great part to the same agency. This may be 
 proved by a simple and by no means rare phenomenon. When the leaves of 
 a tree or bush are in their full autumnal colouration, a portion of one may 
 often be found which has been doubled and fastened down by some caterpillar. 
 The part thus covered from the light retains its ordinary green hue, whilst all 
 the rest of the leaf is a maroon or reddish-brown. In the animal world the 
 changes of colour produced by light are generally destructive. The distinction 
 between fast and fugitive colours prevails, however, here, as well as in the 
 products of the dye-house and print-works. Almost all the colours of 
 quadrupeds and birds are fast, sustaining indefinite exposure to sunlight with- 
 out modification. Among insects the colours of beetles and Hemiptera are, 
 
 2 u 
 
6 5 8 
 
 DYEING AND CALICO PRINTING. 
 
 with the exception of a few non-metallic green and pink shades, permanent. 
 Butterflies and moths, on the other hand, no matter how thoroughly protected 
 against air, friction, or other mechanical injury, have their colours completely 
 discharged in the course of a few years even by diffused daylight. Greens, 
 lilacs, and pinks are here, again, the most fugitive, whilst yellows, browns, 
 full reds, and all " metallic" or iridescent spots resist longest. 
 
 Whatever diversity of opinion may prevail concerning the part played by 
 light in the development of colours and in their fixation upon tissues, there 
 can be no doubt as to its influence when once the process of dyeing, printing, 
 or painting is completed. In almost every case it is injurious. The action 
 ranges from rapid destruction, as in the case of safflower pinks, magentas, &c, 
 to gradual deterioration, as with royal blues, chrome blacks, &c. Few colours ; 
 indeed, do not show a distinction if a swatch be cut in halves and preserved, 
 the one in darkness and the other in the light. 
 
 Nor is this action confined to dyed or printed tissues. The colours them- 
 selves, be they dyes or pigments, are also affected by exposure to light. 
 Extract of indigo, if exposed to diffused daylight, gradually loses its blue 
 colour, and is reduced to a faint yellowish green. Mordants also, especially 
 the preparations of iron and tin, lose their affinity for the fibre, and are 
 rendered worthless by even a short exposure to direct sunlight. This change 
 is very marked with the mordant known as nitrate of tin or " bowl-spirits " 
 (see p. 527). By sunshine it is rendered milky and turbid, a great part of the 
 tin in solution is precipitated, and the remainder becomes useless. Cotton or 
 woollen fibre worked in this spoiled mordant and then transferred to the dye- 
 beck, takes only very flat, meagre, and uneven shades. The ordinary per- 
 salts of tin (crimson spirit, oxymuriate, &c.) are little changed in appearance 
 by the action of light, but they do not work on the fibre, the shades ultimately 
 produced closely resembling those obtained with a spirit which has been 
 "fired" (see p. 529). This is not the only case in which the effects of light 
 in dyeing processes agree with those of an elevated temperature. Safflower 
 shades are discharged if dried in too great a heat, far below a temperature 
 injurious to the fibre, just as readily as if exposed to direct sunlight. 
 
 Nitrate of iron, especially if intended for dyeing royal blues, should be kept 
 in the dark until wanted. If this precaution is neglected the mordant becomes 
 turbid, and the shades produced on the fibre are deficient in bloom and 
 brilliance. This result is the more interesting, because solutions of iron 
 intended for use in the manufacture of Prussian blue as a pigment are not 
 injured by the sun's rays. Some practical colour makers, indeed, contend 
 that the beauty of the pigment is improved if the materials are exposed to 
 light previous to precipitation. 
 
 Light is supposed to have an action upon madder from the time when the 
 dried root is ground up and packed very finely in strong casks. The older 
 manufacturers, especially in Zealand and Alsace, have from time almost 
 immemorial considered that madder, while being ground and packed, should 
 be withdrawn entirely from daylight. The custom of the Mcestoven, as the 
 drying and grinding establishments are called in Zealand, was to work by 
 scanty lamplight. In modern times this precaution has been laid aside and 
 the root is generally ground by daylight. There are, however, some persons 
 possessing great practical acquaintance with madder (especially in Zealand) 
 who maintain that the root ground in the dark is better — works better in the 
 
ACTION OF LIGHT. 
 
 659 
 
 cask, as they phrase it — than that ground in the daylight. The latter finds 
 
 its way largely to the garancin manufacturers. An investigation on the 
 
 changes which madder undergoes while in the cask was commenced some 
 
 years ago. Samples were taken out of the casks with a suitable tool every 
 
 ten days*for two years, care being taken to have the casks (about 400 in 
 
 number, each containing 750 kilos., and among them 100 containing madder 
 
 ground by daylight) kept in a dark warehouse where the temperature, 
 
 hygroscopic condition of the air, and the general state of the weather were 
 
 taken into account. The series of experiments was unavoidably interrupted, 
 
 but it was ascertained that there is good reason for preferring the madder 
 
 ground in the dark. 
 
 The following table has been drawn up by F. V. Kallab. The samples were 
 
 exposed to the sun during the months of July, August, and September, 1872. 
 
 and were compared with corresponding samples carefully preserved from the 
 
 action of light : — 
 
 Influence of Sunlight. 
 
 Dye-ware. 
 
 Indigo blue. 
 Copperas vat on cotton. 
 Vat blue on woollens. 
 Extract of indigo. 
 Purple extract. 
 Prussian blue. 
 
 Logwood blue. 
 
 Aniline blue (?) 
 
 Nicholson blue. 
 
 Weld yellow. 
 Quercitron. 
 Flavin yellow. 
 Berries, yellow. 
 ,, orange. 
 Fustic yellow. 
 Young fustic orange. 
 
 Turmeric yellow. 
 Picric yellow. 
 
 Blackley orange. 
 
 From three to eight days. 
 No change. 
 
 Paler. 
 
 Rather paler. 
 
 Paler by day ; recovers its 
 former shade by night. 
 
 Paler. 
 
 Much paler. 
 
 Little change. 
 
 Unchanged. 
 Paler. 
 
 Duller. 
 
 Dirty orange. 
 
 Paler. 
 
 Much paler. 
 (Light shades, whitish. 
 1 Dark ditto, straw. 
 
 Orange. 
 
 No change. 
 
 Campo-bello yellow 
 Buff (iron). 
 Chrome yellow 
 orange. 
 
 and 
 
 Three months. 
 
 Much lighter. 
 
 Greenish. 
 
 Pure blue but lighter. 
 
 Very pale and greenish, 
 
 Less bloomy and paler. 
 
 If rinsed in water in 
 the evening the lost 
 colour does not re- 
 return. 
 
 Grey ; lilac shades 
 nearly white. 
 
 Very pale ; light shades 
 white. 
 
 Paler and duller. 
 
 Greyer. 
 
 Rather paler. 
 
 Straw colour. 
 
 Nearly white. 
 
 Dirty yellow. 
 
 Pale dirty orange. 
 
 Dirty straw. 
 
 Quite white. 
 
 Reddish. 
 
 Like dark young fustic 
 
 yellow. 
 Turns a little paler at 
 
 last. 
 Pale reddish at last. 
 No change. 
 Duller ; greenish. 
 

 ■1 
 
 66o 
 
 DYEING AND CALICO PRINTING. 
 
 Influence of Sunlight. 
 
 Dye-ware. 
 Annatto yellow. 
 Madder red (cotton). 
 
 Alizarin, pure. 
 
 „ artificial. 
 Cochineal. 
 
 Ammoniacal cochineal. 
 Red wood reds. 
 Safflower red. 
 
 Saffranin. 
 Murexide. 
 Magenta. 
 
 Chloronaphthalic acid. 
 Orchil. 
 
 Aniline violet. 
 Alkanet. 
 Madder purple. 
 „ brown. 
 Catechu. 
 Phenyl brown. 
 
 From three to eight days. 
 Redder. 
 No change. 
 
 Three months. 
 Bright. 
 
 Printed, paler ; dyed, 
 purer and brighter. 
 No change. 
 
 „ „ Rose, paler ; scarlet, 
 
 bluer; crimson, paler. 
 
 — Much bleached. 
 
 Dull. Pale flesh colour. 
 
 Paler in a few hours ; much Quite bleached. 
 
 bleached in eight days. 
 Stands better than safflower. ,, „ 
 
 Duller and paler. 
 
 Unchanged. 
 Duller and paler. 
 Stands better than orchil. 
 
 i> )> 
 
 No change. 
 
 Schweinfurt green. 
 Stove whites. 
 
 Neariy ,, 
 
 Bluish, much bleached. 
 
 Turns flesh colour. 
 
 Light flesh colour. 
 
 Much bleached. 
 
 Bleached. 
 
 Scarcely changed. 
 >» »» 
 
 Yellowish and pale. 
 
 Not darkened with oxi- 
 disers, more in- 
 tense ; darkened, 
 lighter & yellowish. 
 
 Compound browns. 
 
 Duller. 
 
 — 
 
 
 r On wool, lighter. 
 
 Light shades, wool, 
 
 Iodine green. 
 
 
 white. 
 
 
 ^On cotton, bleached. 
 
 Dark shades, cotton, 
 bleached. 
 
 Iodine green with picric 
 
 Duller. 
 
 Dirty yellow green. 
 
 acid. 
 
 
 
 Extract of indigo with 
 
 Yellower. 
 
 Pale olive green. 
 
 picric acid. 
 
 
 
 Ditto with fustic. 
 
 Less changed. 
 
 Pale and dull. 
 
 Vat-blue with vegetable 
 
 ii ii 
 
 Bluer. 
 
 yellow. 
 
 
 
 Vat blue with chrome 
 
 Unchanged. 
 
 Duller. 
 
 yellow. 
 
 
 
 Fustic and logwood 
 
 Duller. 
 
 Pale. 
 
 green. 
 
 
 
 Guignet's green. 
 
 No change. 
 
 No change. 
 
 If with sulphur alone, 
 lose merely the blue 
 surface shade ; if 
 soap was present, 
 turn yellowish. 
 
ACTION OF LIGHT. 
 
 66 1 
 
 Influence of Sunlight. 
 
 Dye-ware, 
 
 French whites with 
 extract of indigo, 
 orchil, and chloride 
 of tin. 
 
 Logwood black. 
 
 Aniline black. 
 
 From three to eight days. 
 Bluer. 
 
 No change. 
 
 Three months. 
 Orchil quite bleached, 
 leaving a greenish 
 white. 
 
 Chrome, greenish; cop- 
 peras, little change. 
 
 Wool, no change ; 
 cotton, greenish. 
 

 662 
 
 CHAPTER IX. 
 
 DETECTION OF DYES ON YARN OR PIECES, 
 
 "TVYERS generally judge of the composition of any colour which they meet 
 ^ with, either by simple inspection or by certain routine processes which 
 have been traditionally handed down from generation to generation. Even at 
 the present day there are many dyers who believe that the colouring matters 
 of commerce cannot be detected with certainty. Hence they employ the 
 known reactions of tinctorial substances as little as possible. In order to 
 show how far even a slight knowledge of chemistry will aid in the recognition 
 of dyes, we give simple directions, arranged under the six heads of Black, 
 Blue, Yellow, Red, Green, and Violet. 
 
 The apparatus employed is very simple. For steeping the tissues or 
 skeins of silk, cotton, or wool, a small white porcelain capsule is needed, and 
 for the application of heat a small iron tripod, with a spirit-lamp or Bunsen 
 gas-burner. The white colour of the porcelain renders it easy to observe the 
 changes of colour under the influence of reagents. In order to reduce 
 portions of the tissue to ashes, a small platinum capsule or piece of platinum 
 foil is used, which may be heated to redness in the flame until all combustible 
 matter is employed and only the ash remains. The colour of the ash 
 indicates the character of the dye, of which more below. It may be green, 
 blue, grey, white, or red. 
 
 A. BLACKS. 
 
 1. Chrome Blacks. — Chlorine-gas, or solution of bleaching-lime, turns 
 these a kind of chestnut-brown. If exposed to bright sunshine they become 
 greenish. If thoroughly burned they leave a greenish ash. 
 
 2. Logwood with Iron. Mordantf-. — Dilute hydrochloric acid turns the 
 swatch a cherry-red. The prompt application of a dilute alkali restores the 
 black. Solution of bleaching-lime discharges the black, leaving a yellowish 
 ground (oxide of iron). The cloth leaves a yellowish-brown ash. 
 
 3. Galls with Iron Mordants. — This dye is chiefly found on the better 
 class of silks. Hydrochloric acid gives no immediate red colour. Bleaching- 
 liquor discharges the black, leaving the iron ground as above. 
 
 4. Logwood with Iron on a " Woaded," i.e., Vat-Blue, Bottom. — 
 Hydrochloric acid has no immediate action, but gives in a few minutes a 
 dull purpl'sh red spot. A mixture of hydrochloric and oxalic acids extracts a 
 
DETECTION OF DYES. 663 
 
 red liquid, and leaves a blue bottom. Nitric acid extracts a similar liquid, 
 but leaves a yellowish-brown ground. 
 
 5. Aniline Black.- — Strong hydrochloric acid gives no immediate change, 
 but after a quarter of an hour the cloth will be found to have taken a greenish- 
 yellow, while the liquid is an olive-brown. 
 
 6. Lamp-Black. — Cannot be discharged. Ash white. 
 
 B. BLUES. 
 The principal blue colours of which we shall speak are : — 
 
 1. Logwood blue. 
 
 2. Prussian blue. 
 
 3. Aniline blue. 
 
 4. Indigo blue. 
 
 5. Mixed blues. 
 
 6. Ultramarine blue. 
 
 I. We begin by placing a piece of the cloth to be tested in a solution of 
 citric acid, or in hydrochloric acid treated with water. 
 
 a. The colour changes to red or orange Logwood. 
 
 b. The colour does not change. (In this case any of the other three 
 
 dye-wares may be present.) 
 
 II. Another portion of the cloth is placed in a solution of chloride of lime. 
 
 a. Colour unaltered Prussian blue. 
 
 b. Sample discoloured or turned yellowish Blues 3 or 4. 
 
 III. In order to distinguish between these two blues we put a third swatch 
 into a solution of caustic soda. 
 
 a. Sample discharged or altered Aniline. 
 
 b. Sample unchanged Indigo. 
 
 We may satisfy ourselves of the correctness of our results by the application 
 
 of the following corroborative tests : — 
 
 The Blue of Logwood is reddened by acids and restored by caustic soda. 
 The cloth when burnt leaves white or grey ash ; the whiteness being due to 
 the alumina of the alum used as a mordant, and the grey tint caused by the 
 oxide of copper contained in the blue vitriol used with the wood. If copper 
 is present the edge of the flame appears green during combustion. 
 
 Prussian Blue being a cyanide of iron leaves on combustion a red ash, 
 oxide of iron, more abundant in proportion as the blue is deeper. 
 
 Indigo Blues contain no mineral matter, and leave no ash except that of 
 the cloth. They may be either vat-colours, China blues, pencil blues, or 
 extradt of indigo. These are distinguished as follows : — ■ 
 
 1. Indigo, Vat. — A piece of clean white silk rubbed on the cloth becomes 
 smeared. Sulphuric and muriatic acids, and carbonates of soda and potash, 
 produce no change. Strong nitric acid destroys the blue, leaving a clear 
 yellow, if no other colouring matter is present. Chlorine destroys the colour. 
 
 2. Indigo, China Blue. — Behaves like a vat-blue. If the colour is 
 destroyed with chlorine, the cloth is not dyed on dipping in logwood liquor. 
 
 3. Indigo, Pencil Blue. — Behaves like the two former, but if dipped in 
 logwood liquor after the colour has been destroyed with chlorine it is dyed red. 
 
 4. Extract of Indigo.— Unlike a vat-blue, it does not soil white silk on 
 friction. Strong alkalies dissolve the colour, forming a blue solution. Nitric 
 acid destroys it more rapidly than a vat-blue. 
 
664 
 
 DYEING AND CALICO PRINTING. 
 
 Aniline Blues when burnt leave merely the ash of the fabric. On steeping 
 a swatch of the cloth in alcohol we obtain a beautiful blue liquid, not 
 reddened by citric acid. The liquid obtained from a logwood blue turns red 
 at once if mixed with an acid. Dilute acids and solutions of the carbonates 
 of soda and potash produce no change. Concentrated acids turn the blue to 
 a green, but washing in abundance of water restores the blue, in a somewhat 
 fainter shade. Caustic soda turns the blue to a reddish-brown. 
 
 Prussian Blues.- -Dilute acids produce no change. Concentrated nitric 
 acid alters the shade to a green, which washing does not re-convert into blue. 
 Solutions of alkalies, both caustic and carbonated, give a rust-colour (oxide of 
 iron), different from the red shade which caustic soda gives on aniline blues, 
 and incapable of re-conversion into blue by washing in water. 
 
 Mixed Blues. — Vat-blue, in order to economise indigo, is sometimes 
 "topped," and in other cases "grounded," with the redwoods, — especially 
 camwood and sanders, — with cudbear, and even with yellows, as fustic. In 
 this case sulphuric and muriatic acids should be applied, at first dilute and 
 afterwards concentrated, noting if the liquid is turned red or yellow. In the 
 former case wood or weed colours are present. If a vat-blue, grounded with 
 any other colour, is discharged with concentrated nitric acid, the colour 
 remaining is not the clear yellow which unmixed indigo gives under similar 
 circumstances, but a brownish shade. 
 
 Ultramarine Blue (Pigment Styles). — The swatch is steeped for a time 
 in a mixture of ether and alcohol, to remove any resinous matter with which 
 the colour may have been fixed, and then moistened with hydrochloric acid. 
 The colour disappears, with the smell of putrid eggs. 
 
 C. YELLOWS. 
 The yellows on whose nature we are able to pronounce are : — 
 i. Iron buff. 
 2. Picric acid. 
 Turmeric. 
 Fustic. 
 Weld. 
 
 Persian beries. 
 Bark (quercitron). 
 
 8. Chrome yellows and oranges. 
 
 9. Annatto. 
 
 I. In order to distinguish between these colours, we begin by ascertaining 
 the presence or absence of iron-yellow and of picric acid. To effe<5t this, two 
 swatches of the cloth are cut off, and the one is steeped in a iuke-warm and 
 slightly acid solution of yellow prussiate of potash, and the second in a hot 
 solution of cyanide of potassium. If the prussiate gives a blue colour we may 
 be certain that the sample is an iron-buff. If the cyanide gives a red colouration 
 picric acid is present. Picric acid is extra&ed by alkalies and albumen. 
 Acids produce no change. 
 
 II. If neither of these results appears iron and picric acid are both pro- 
 nounced absent. We then take a fresh swatch and put it in a boiling solution 
 of 1 part of soap in 200 of water. The following reactions may then take 
 place : — 
 
'■ 
 
 a. 
 
 DETECTION OF DYES. 665 
 The colour of the cloth changes to a brown, and is restored to a yellow 
 
 
 b. The cloth is nearly decolourised Fustic. 
 
 c. The soap has little or no action. In this latter case we may have 
 
 weld, berries, or bark. 
 
 To distinguish these three colours, we take a fresh swatch and submit it to 
 a bath of very dilute boiling sulphuric acid. If the colour fades it is weld ; 
 if it does not change it is berries or bark. We then take another swatch and 
 soak it in a solution of tin crystals. If the colour changes to orange it is 
 berry-yellow. If scarcely affected it is bark or flavin. 
 
 If we suspect a bottom of annatto we soak a swatch in concentrated sul- 
 phuric acid. The colour changes suddenly to greenish blue. Annatto is the 
 only tinctorial body presenting this reaction. Bark, berries, fustic, turmeric, 
 and weld are all bleached by chlorine. Annatto resists this reagent. Fustet 
 (young fustic) is rarely met with, except in wool-dyeing. 
 
 Chrome Yellows and Oranges. — Sulphuretted hydrogen or alkaline 
 sulphides blacken them. They are destroyed by caustic soda. 
 
 Annatto. — Chlorine and bleaching-liquor have little action. Concen- 
 trated sulphuric acid turns it a bluish-green. Nitric acid discharges. 
 
 D. REDS. 
 The red dyes that may present themselves are the following : — 
 
 1. Cochineal. 
 
 2. Brazil wood, &c. 
 
 3. Madder and garancin. 
 
 4. Safflower and carthamin. 
 
 5. Aniline-red. 
 
 6. Murexide. 
 
 7. Corallin. 
 
 8. Weed-colours, orchil, cudbear, &c. 
 
 We begin by ascertaining the presence or absence of madder-red. We 
 place in four glasses or capsules the following reagents : — Boiling soap-lyes, 
 caustic ammonia, citric acid (or lemon juice), a mixture of equal parts of tin 
 crystals, hydrochloric acid, and water. In each of these a swatch is plunged. 
 If all four remain unattacked we have madder-red. If there is a change we 
 infer its absence and the presence of one of the other reds. 
 
 Complete decolouration by soap-lyes indicates safflower. In this case the 
 colour reappears with its original shade on washing in pure water and 
 brightening with citric acid. If on washing with water and brightening the 
 colour reappears fainter, we have aniline red. If the washing and brightening 
 change the red to an orange or yellow, we have cochineal or Brazil-wood. 
 We may distinguish between these two colours as follows : — A swatch of the 
 original fabric, steeped in sulphuric acid, is turned a cherry-red if it be 
 Brazil-wood, and a yellowish orange if cochineal. 
 
 Murexide.— It is discharged by citric acid and by boiling soap-lye. 
 
 Corallin. — If a swatch is digested in hot alcohol the colour is extracted. 
 The addition of ammonia then brightens the liquid. 
 
 Weed-Colours, Orchil, Cudbear, &c. — Destroyed by solution of tin 
 crystals. 
 
666 
 
 DYEING AND CALICO PRINTING. 
 
 E. GREENS. 
 The greens most commonly met with in dyed goods are of three kinds :— 
 
 1. Greens obtained with a mixture of yellow and blue. 
 
 2. Aniline (aldehyd) green. 
 
 3. Iodine green. 
 
 Lao-kao, chlorophyl, &c, are rarely met with. The greens made up of 
 yellow and blue are . — 
 
 1. Indigo and picric acid. 
 
 2. Indigo and vegetable yellows. 
 
 3. Prussian blue and picric acid. 
 
 4. Prussian blue and vegetable yellows. 
 
 5. Aniline blue and vegetable yellows. 
 
 6. Aniline blue and picric acid. 
 
 In these mixed greens the blues form the bottom and, excepting aniline 
 blue, are insoluble in alcohol. All the yellows given are soluble in alcohol. 
 Hence a green, soluble in alcohol with a green colour, must be a mixture of 
 aniline blue and yellow. 
 
 Into a small flask is poured some alcohol at 95 per cent, into which a 
 swatch of the cloth is immersed. The alcohol is raised to and maintained at 
 the boiling-point for a few minutes on the water-bath. Two results may 
 follow : — 
 
 1. The alcohol becomes yellow, and the tissue turns gradually more blue. 
 
 2. The alcohol becomes green, whilst the cloth grows paler, but without 
 
 altering its tone. 
 
 In the former case the bottom is indigo or Prussian blue. When the swatch 
 has given up all its yellow colour to the alcohol, it is taken out, washed in 
 pure water, and placed in a glass with a solution of chloride of lime. If the 
 bottom is indigo, the colour will be attacked, but if Prussian blue, it will 
 remain unchanged. The alcoholic liquid remaining in the flask may contain 
 several colouring matters. It is divided into portions, which are then tested 
 according to the instructions given for yellows. 
 
 In the second case we have aldehyd or iodine green, or aniline blue along 
 with a yellow. In order to distinguish between these colours, we boil a 
 swatch in dilute hydrochloric acid. The cloth becomes : — 
 
 a. Rose or lilac Iodine green. 
 
 b. Blue, the yellow being discharged . . . . Aniline blue and a yellow. 
 
 c. Discharged, or yellowish Aldehyd green. 
 
 If it be found that the green is a mixture of aniline blue and a yellow, the 
 
 nature of the latter may be determined as above directed. 
 
 A swatch may be placed in a solution of carbonate of soda, noting whether a 
 blue colour is dissolved out. If so, the blue portion of the green is extract of 
 indigo. If the swatch is turned a rusty colour by alkalies, the blue is a Prussian. 
 This is most to be expected on cotton goods. If the green is blackened by 
 sulphuretted hydrogen, and if a blue remains on carefully washing with a 
 dilute acid, chromate of lead is one of the ingredients. In this case, for cor- 
 roboration, burn a swatch to ashes in a light porcelain — not platinum — 
 capsule, and extract the ash with dilute nitric acid. If chromate of potash 
 gives a yellow precipitate in the filtered liquid, chrome-yellow was originally 
 present. 
 
DETECTION OF DYES. 
 
 667 
 
 If the green is a chrome-green, such as Guignet's, oxide of chrome will 
 remain in the ash, which will have a dull green colour. 
 
 If the green is arsenical, such as Scheele's green, a piece of the cloth, on 
 burning, gives a green tinge to the flame. The ash is extracted with nitric or 
 hydrochloric acid. The clear solution is freed from excess of acid by evapo- 
 ration at a gentle heat, diluted with a little water, and mixed with ammonia 
 in excess. A blue colour will appear from the copper present in the arsenical 
 greens. 
 
 On woollen and worsted goods, if soda dissolves off extract of indigo, the 
 yellow portion will probably be fustic. If the blue is a Prussian or royal, the 
 yellow will generally be bark or flavin. 
 
 F. VIOLET. 
 The violets here indicated are: — 
 1. Common aniline violet, 
 j. Iodine (Hofmann) violet. 
 
 3. Madder purple. 
 
 4. Alkanet violet. 
 
 5. Orchil violet. 
 
 6. Logwood violet. 
 
 7. Cochineal purple. 
 
 We first steep a swatch in solution of chloride of lime. If it resist it is 
 alkanet violet. If there is a change of colour we have one of the six others. 
 
 A second swatch is then steeped in lime-juice. If the violet be not 
 heightened in tone we have one of the two aniline violets. If it becomes red, 
 or even yellow, we may have madder, orchil, cochineal, or logwood. To 
 distinguish these a swatch is steeped in chloride of lime, then washed in 
 water, and placed in an acid solution of yellow prussiate of potash. As 
 madder and cochineal purples have oxide of iron for their mordant, which 
 remains attached to the fibre, Prussian blue is formed in case of these two 
 colours. If there is no blue colouration, we have orchil or logwood. It 
 remains then to distinguish between — 
 
 1. Madder purple and cochineal purple. 
 
 2. Orchil violet and logwood purple. 
 
 3. Common aniline violet and Hofmann violet. 
 
 A fresh swatch of the cloth is steeped in chloride of lime. It is turned a 
 Nankeen yellow if dyed with madder, and is completely discharged if dyed 
 with cochineal. 
 
 A swatch steeped in milk of lime becomes greyish, and, finally, colourless 
 if dyed with logwood ; but changes to a violet-blue if dyed with orchil. 
 
 A swatch steeped in hydrochloric acid diluted with three times its measure 
 of water becomes blue-violet, and after washing with water a little redder, in 
 case of common aniline violet. In case of iodine (Hofmann's) violet, the 
 fabric becomes blue, greenish, and after washing with water a clear lilac, or 
 pearl-grey, according to the original depth of shade. 
 
 A red ash (iron mordant) indicates madder or cochineal. A white ash (alum 
 mordant) indicates logwood. Absence of ash shows the aniline violets. 
 
 A peculiar pigment violet is produced by a mixture of ultramarine and ver- 
 million. If this is treated with dilute acid the blue is destroyed, while the red 
 
^mitmmimm 
 
 668 
 
 DYEING AND CALICO PRINTING. 
 
 of the vermillion remains. Subsequent treatment with an alkali does not 
 affecft the red or restore the original shade. 
 
 In all these directions it must be understood that madder comprehends 
 garancin and alizarin, natural or artificial. Cochineal must, in like manner, 
 be taken to include lac. 
 
 The nature of the fibre often gives a clue to the colour, which should not be 
 overlooked. Thus among yellows, picric acid is not to be expected upon 
 cotton, nor is iron-buff often found upon wool. Reds upon cotton are rarely 
 cochineal, — usually madder, or the woods. Upon woollen or worsted, cochi- 
 neal or magenta is more probable. Upon cotton, aniline blues are less likely 
 than upon wool and silk. 
 
DETECTION OF DYES. 
 
 669 
 
 
 
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(673) 
 
 APPENDIX. 
 
 t. Preparation of Picric Acid. — Guinon arranges in a sand-bath two 
 series of flasks, each containing an equal weight of nitric acid of sp. gr. 1*3. 
 Crude carbolic acid is allowed to flow drop by drop into each from a vessel 
 placed above, through glass tubes, no external heat being applied. All the 
 flasks communicate by means of glass tubes with a large stoneware vessel, 
 which receives the acid fumes given off; part of them are condensed there, 
 and the rest escape through the chimney. When the falling drops of carbolic 
 acid undergo no further change, the supply is cut off, and a gentle heat is 
 applied to the sand-bath, to effect the transformation of the resinous mass still 
 floating in the flasks. The contents are finally poured into capsules where the 
 picric acid is deposited, on cooling, partly in coherent clots, and partly in fine 
 crystals. It is placed in a funnel, the throat of which is loosely filled with 
 fragments of quartz or of bricks free from lime. The nitric acid gradually 
 drains away, whilst the picric remains. It is still contaminated with a little 
 resinous matter, to remove which it is dissolved in boiling water containing 
 tdVu °f sulphuric acid, in which the impurities remain insoluble. Perra pre- 
 pares picric acid as follows : — 600 parts by weight of nitric acid, of sp. gr. I'j. 
 are placed in a flask, and 100 parts of carbolic acid are gradually added. The 
 nitric acid volatilised during the reaction is condensed by means of a cohobator, 
 and allowed to flow back upon the carbolic acid. The yield thus obtained 
 varies from go to no per cent of the carbolic acid employed. 
 
 Carey Lea prepares picric acid from Australian "Yellow Gum," the resin of 
 Xanthorrhcea hastilis, as follows : — 150 grms. of the resin, powdered and placed 
 in a capsule containing 2 or 3 litres, are moistened with 300 grms. of nitric 
 acid, of sp. gr. 1-42. As soon as the aftion begins 750 grms. of boiling water, 
 which should be ready at hand, are added. Heat is applied, when the mass 
 swells up and threatens to run over, which must be prevented by the addition 
 of small quantities of cold water and by a judicious regulation of the tem- 
 perature. When the volume of the liquid has diminished one-half, 150 more 
 grrns. of nitric acid are added, and the heating is continued till the liquid is 
 reduced to its former bulk. From 120 to 200 parts of nitric acid are still 
 required to complete the operation. The liquid is then evaporptcd down to 
 the bulk of 120 to 150 c.c. On cooling the residue solidifies. The yield is 
 from 25 to 50 per cent of the yellow gum employed. 
 
 2X 
 
■ 
 
 674 
 
 DYEING AND CALICO PRINTING. 
 
 i. Isopurpuric Acid. — The best results are obtained with an isopurpurate 
 of aniline. To obtain this salt, which is formed in the dye-beck, ioo parts 
 isopurpurate of potash are mixed with 42 parts hydrochlorate of aniline. 
 
 Wool which has previously been boiled for two hours in the ordinary 
 manner with 4 parts of alum and 1 cream of tartar takes rapidly a chestnut- 
 brown colour. Silk mordanted with alum (to which one-tenth of its weight 
 of soda crystals have been added) dyes up a rose with a violet tinge in the 
 isopurpurates of potash or ammonia, but a deep garnet brown with the 
 isopurpurates of baryta or aniline. 
 
 3. Rosolic Acid. — Jourdin heats phenate of soda with peroxide of mercury 
 to a little above 150' C. for ten minutes, and obtains thus a rich red solution 
 of the rosolate of soda. 
 
 Kolbe mixes in a tubulated retort 1 part of oxalic acid, ij of carbolic acid, 
 and 2 of sulphuric acid, and heats to 140 to 150 C. for 4 to 5 hours. The 
 red-brown residue, as soon as it begins to swell up, is thrown into water 
 and boiled, adding fresh portions of water till the odour of carbolic acid 
 disappears. The deep-brown paste which remains undissolved, dissolves in 
 ammonia with a magnificent purple colour. 
 
 4. Fol's Yellow. — This colour, derived from carbolic acid, is of an acid 
 nature, and forms red compounds with bases. To prepare it heat for twelve 
 hours, at ioo 3 C. in an open cast-iron boiler, 5 parts of carbolic acid and 3 parts 
 of arsenic acid, dried and finely powdered. The colouration appears at the 
 end of two hours, and increases gradually in intensity as the matter thickens 
 and gives off steam. After 12 hours the temperature is raised to 125' C, and 
 kept at that heat for 6 hours. When the mass ceases to swell up 10 parts of 
 acetic acid at 7 B. are added. The mass is dissolved in abundance of 
 water, the solution is filtered through calico, and mixed with salt in excess, 
 which precipitates the colouring matter in flocks. It is purified by combining 
 with baryta and decomposing the barytic salt with sulphuric acid. The pure 
 product separates out in the form of reddish-brown lamella?. It dissolves 
 easily in cold and hot water, ether, alcohol, and wood-spirit. In presence of 
 caustic or carbonated lime or baryta it dyes wool and silk all shades of red. 
 These colours are not affected by soap. If used alone it gives varied shades 
 of yellow. It is frequently employed along with rosolic acid and other colours 
 to produce browns. 
 
 5. Campo-Bello Yellow is prepared by a secret process by Schrader and 
 Berend, of SchOnefeld, Leipzig. It is a derivative of carbolic acid, and is 
 advantageously used in wool-dyeing. It produces all shades of yellow, and 
 resists solutions of carbonate of soda at 20 B. For use it is dissolved in 
 boiling water and filtered. 1 he solution is boiled, and the wool plunged for 
 half an hour in the boiling liquid ; 300 grms. of alum may be added for each 
 5 kilos, of wool. Campo-bello yellow mixed with magenta, indigo, &ic., 
 yields a variety of useful colours. 
 
 6. Phenicienne. — The nitro-sulphuric acid employed in preparing this 
 colour consists of 2 volumes of common oil of vitriol and 1 volume of nitric 
 acid, at sp. gr. 1*35. 
 
 7. Chloride of Benzyl. — Lauth and Grimaux have obtained a fiine 
 violet by the direct action of chloride of benzyl upon rosaniline, and when 
 Hofmann's " Violet R" is used in place of rosaniline a violet is formed of a 
 decided blue shade. For the preparation of chloride of benzyl an apparatus 
 
APPENDIX. 675 
 
 is employed which can be used at will either for cohobation or distillation. 
 Toluen is introduced into this apparatus and quickly brought to a boil, and a 
 current of chlorine is brought in contact with its vapours, which are directed 
 into the cohobator, where the toluen and the chloride of benzyl formed are con- 
 densed and fall back. When a thermometer immersed in the boiling toluen 
 marks 140° to 150 C, the current of chlorine is shut off and distillation 
 begins. All that passes over below 170 C. is collected separately, and is again 
 treated with chlorine. What distils between 170 and 180 is submitted to a 
 new rectification. Finally, what goes over between 174 and 176 C. is nearly 
 pure chloride of benzyl. 
 
 8. Diphenylamine yields a magnificent blue colour with concentrated 
 nitric acid, methyl-diphenylamine, which is obtained by treating diphenylamine 
 by iodide of methyl at temperatures above ioo° C. It yields blue or violet 
 compounds with arsenic acid, the metallic nitrates, chlorides, iodides, 
 bromides, iodine, chlorate of potash, sesquichloride of carbon, chloral, &c. 
 
 9. Cerise. — The trade name of a colour sold by the firms of Geigy, of Basle, 
 and Knosp, of Stuttgardt. It is prepared from magenta residues, and dyes 
 shades more inclining to a scarlet. After the crude magenta has been boiled 
 in water and the pure magenta precipitated with common salt, carbonate of 
 soda is added to the remaining liquid, and the precipitate thus obtained is 
 collected and dried. It is probably a mixture of rosaniline with chrysaniline 
 and chrysotoluidine. 
 
 10. Coupier's Aniline Reds. — Coupier dispenses with arsenic, and obtains 
 reds — (1) with pure or nearly pure aniline and nitro-toluen ; (2) with ordinary 
 commercial aniline and common nitro-benzin ; (3) with nitro-toluen and toluidine 
 or with nitro-xylen and xylidine. In each case he adds perchloride of iron and 
 hydrochloric acid. The two former mixtures yield reds identical with common 
 magenta ; the third gives a product which Coupier names roso-toluidine, 
 toluidine-red, or xylidine-red. The ingredients to be used for the last-mentioned 
 colour are : — 
 
 Nitro-toluen 95 parts. 
 
 Hydrochloric acid 65 ,, 
 
 To which are then added — 
 
 Toluidine 67 parts. 
 
 Perchloride of iron 7 or 8 parts. 
 
 The method of conducting the operation on the large scale is as follows : — 
 Any of the above mixtures is placed in an enamelled cast-iron vessel, and 
 heated gradually to 200° C. The progress of the reaction is judged by the 
 indications of a thermometer plunged in the mass, by the nature of the 
 vapours given off, and by the appearance of the mixture, of which a specimen 
 is taken from time to time. The product, on cooling, becomes a solid, brittle 
 mass, like raw magenta-melt. It is powdered, boiled in water, and the 
 colouring matter is thrown down by means of carbonate of soda, and purified 
 in the ordinary manner. 
 
 11. Hofmann's Xylidin Red is prepared by heating a mixture of pure 
 xylidin and pure aniline with an oxidising agent. It is a splendid crimson- 
 red colour, producing shades-very similar to those yielded by magenta. It is 
 
 evidently distinct from Coupier's xylidin-red. 
 
 2x2 
 
676 DYEING AND CALICO PRINTING. 
 
 12. Ulrich's Scarlet. — Mix 4 parts by weight of acetate of rosaniline and 
 3 parts nitrate of lead dissolved in the smallest possible quantity of boiling 
 water; the mixture is boiled and evaporated to dryness. The dry mass is 
 heated to 150 to 200 C, until it suddenly becomes violet. When cool it is 
 again boiled for some time in water slightly acidulated with sulphuric acid. 
 The acid solution is neutralised with an alkali and filtered whilst boiling. 
 From the filtrate the colouring matter is thrown down by means of common 
 salt. The precipitate is collected on a filter and dried. 
 
 This scarlet, on ethylation or methylation, furnishes a rose-red colouring 
 matter. For this purpose it is dissolved in alcohol, the solution mixed with 
 iodide of ethyl (or methyl), and heated for some time in an autoclave. From 
 the product the new colouring matter is extracted in the same manner as 
 Hofmann's violet. 
 
 13. Hofmann Violet, R R R. — The accompanying pattern, kindly furnished 
 by Messrs. Brooke, Simpson, and Spiller, shows the reddest shade of the 
 Hofmann violets, the manufacture of which has been described upon p. 192. 
 The colour is perfectly soluble in hot water, and upon animal fibre requires 
 no mordant. In dyeing woollens, the goods are entered at 120 F., and 
 dyed slowly up to the boiling-point. Care must be taken not to overload the 
 beck with colour. 
 
 14. Dorothea Violet. — H. Lewinstein produces this colour, which approxi- 
 mates to Hofmann's violet, by mixing 50 parts of alcohal at 90 per cent, 
 35 parts of rosaniline, and 7 parts of nitric ether, and heating the mixture to 
 ioo° C. for two or three hours. 
 
 15. Wanklyn's Violet. — The inventor prepares first the iodide of pseudo- 
 propyl by acting upon glycerin with hydriodic acid. This body is then mixed 
 with an equal weight of rosaniline, and with the addition of alcohol is heated 
 to 100° C. in closed vessels. The resulting mass is treated with caustic soda- 
 lye, and the violet dye is thus obtained in a state sufficiently pure for use. 
 
 16. Paris Violet (Poirrier's Violet). — The patentees take — (1) 50 or 
 80 parts by weight of methylic alcohol and 100 parts of hydrochlorate of 
 aniline ; (2) 100 parts of commercial aniline, 160 parts of sal-ammoniac, and 
 50 or 80 parts of methylic alcohol. These mixtures are heated for three or 
 
 - four hours in an enamelled Papin's digester to 250 or 300° C. The latter 
 mixture attacks the iron less. Hydriodate or hydrobromate of aniline may 
 be used instead of the hydrochlorate, and require a lower temperature. The 
 product of the reaction is repeatedly washed with a lye of caustic soda, which 
 decomposes the salts of methylaniline or ethylaniline formed. The oil thus 
 separated is rectified, and is then sufficiently pure. The product obtained is 
 mixed with 5 or 6 parts of anhydrous chloride of tin with brisk agitation. 
 The mixture is heated to ioo° C, and at the expiration of some hours it 
 becomes hard and solid. When the reaction is at an end the mass is allowed 
 to cool. It is freed from all foreign matters by boiling the mass with caustic 
 soda and washing it therewith, when the base of the colouring matter remains 
 with a deep shade. The colour is then regenerated by the addition of any 
 acid. Instead of the process with chloride of tin we may take : — 
 
 Sulphate of methylaniline 100 
 
 Chlorate of potash, powdered 100 to 150 
 
 Water 100 to 150 
 
■1 ■■■■ 
 
 
 APPENDIX, 
 
 677 
 
 Hofmann Violet, RRR. 
 
 and heat for several hours to 160" C. The dye produced is very soluble In 
 water even in the cold. 
 
 17. Lauth's Violet. — According to the last improvement the patentee heats 
 meth^'laniline to 120 with half its weight of hydrochloric acid till the colouring 
 matter is formed ; or to 100° C. with half of its weight of nitrate of copper ; 
 or he heats to ioo° C. 1 part of acetate of methylaniline with £ part oxide of 
 mercury. The longer the mixture is heated the more blue are the shades 
 produced. 
 
 18. Spiller's Purple. — This colour is a violet of a very blue shade, manu- 
 factured by the distinguished firm of Brooke, Simpson, and Spiller, to whose 
 kindness we are indebted for the accompanying specimen. 
 
 Spiller's Purple. 
 
678 DYEING AND CALICO PRINTING. 
 
 19. Methyl-diphenylamine Violet. — Place upon copper plates arranged 
 in a stove heated by steam — 
 
 Hydrochlorate of methyl-benzyl-phenylamine . . 3 kilos. 
 
 Sulphate of copper : . 1 kilo. 
 
 Chlorate of potash 0*2 „ 
 
 Siliceous sand 20 kilos. 
 
 Hydrochlorate of essence of terebenthin .. .. 2 ,, 
 The stove must be so arranged as to permit of a free circulation of air. An 
 excess of moisture is kept up by the injection of a little steam, and the 
 mixture is frequently stirred. The temperature is maintained at 45 to 70° C. 
 The operation is considered at an end when nothing more of an oily nature is 
 perceived. The product is then repeatedly extracted with boiling water, which 
 takes up the soluble metallic salts. In order to dissolve the colouring matter 
 mixed with the sand either alcohol or strong hydrochloric acid may be used. 
 When the sand is exhausted all the coloured solutions are mixed and 
 distilled if alcohol has been used, or diluted with water and precipitated with 
 common salt if hydrochloiic acid has been employed. The colour thus 
 obtained is transmuted into a base by means of soda or potash. The base is 
 washed with water and taken up with acetic or hydrochloric acid. These 
 salts are very soluble and dye blue-violets. 
 
 Others of the mixed tertiary monamines, as methyl-diphenylamine, benzyl- 
 diphenylamine, benzyl-phenyl-toluylamine, and benzyl-ditoluylamine yield 
 similar colours. 
 
 20. Paris Green. — Poirrier, Bardy, and Lauth prepare this new green 
 colour by acting with an oxidiser — such as bromine, iodine, chlorine, weak 
 nitric acid, nitrates of mercury copper and other metals, and solution of 
 chloride of iodine in ten times its weight of water — upon benzyl- or dibenzyl- 
 aniline, tolyl- or ditolyl-aniline, benzyl- or dibenzyl-toluidine, tolyl- or ditolyl- 
 toluidine, and their mixtures. 
 
 21. Methylaniline Green. — This colour, which is generally replacing 
 iodine green, is prepared by causing nitrate of methyl to react upon Poirrier's 
 violet (methylaniline violet). The separation of the violet and green 
 colouring matters is effected by the addition of a solution of chloride of zinc 
 and gradual saturation with carbonate of soda. A zinc-violet lake is thrown 
 down at first. When all the violet is precipitated and filtered off, the filtrate 
 is concentrated and allowed to cool, when a double chloride of zinc and 
 aniline green crystallises out. 
 
 22. French Yellow; Chryscic Acid (Nitro-xynaphthalic Acid of 
 Dusart and Gelis). — If 100 parts of nitro-naphthalin aie intimately mixed 
 with 250 parts of dry hydrate of lime, and the mixture moistened with 
 75 parts of hydrate of potash dissolved in as little water as possible, and the 
 whole heated for ten to twelve hours to the temperature of 150 C. in an oil- 
 bath with free excess of air, or preferably in a current of oxygen, the mixture 
 becomes oxidised and assumes gradually a deep yellowish-red colour. On 
 treating the mass with hot water and filtering the liquid, we obtain a yellow 
 solution of the nitro-xynaphthalate of potash, and after sufficiently concentrating 
 the liquid, the nitro-xynaphthalic acid maybe precipitated by the addition of any 
 strong acid, in the form of fine yellow flocks, soluble in hot water, alcohol , 
 wood-spirit, and acetic acid. It dyes silk and wool a full golden yellow. 
 
APPENDIX. 
 
 679 
 
 23. Carminaphtha.— If chromic acid, or a mixture of chromate of potash 
 and sulphuric acid is allowed to act upon naphthalin, a fine red colouring 
 matter is frequently formed, under circumstances not yet fully determined. 
 It is a weak acid, almost insoluble in water, soluble in acetic acid and alcohol. 
 With alkalies it forms orange compounds soluble in water, and it dyes 
 silk and wool an orange or a red-violet without the aid of mordants. 
 
 24. Chloroxy-naphthalic Acid. — Naphthalin treated in the cold with the 
 chlorate of potash and hydrochloric acid is transformed into a mixture of 
 bichloride of naphthalin, bichloride of chloro-naphthalin, and certain secondary 
 oily products, which are eliminated by pressure. The residue is heated in a 
 water-bath and oxidised with nitric acid. It is needful to operate cautiously to 
 avoid the formation of large quantities of phthalic acid, and that the bulk 
 of the chloride of chloro-naphthalin may be converted into bichlorated 
 naphtho-quinon, whilst the bichloride of naphthalin forms phthalic and 
 oxalic acids. These acids are removed by boiling water, and the former is 
 subsequently converted into benzoic acid. 
 
 The bichloride cf naphtho-quinon, which is insoluble in water, is dissolved 
 in boiling potash-lye ; the deep-coloured solution is filtered and supersaturated 
 with a mineral acid, when impure chloroxy-naphthalic acid is thrown down. 
 This is re-dissolved in soda-lye and exactly neutralised. To the neutral solution 
 a little alum is added, which precipitates a brown impurity. The liquid is 
 filtered afresh and mixed with a mineral acid, when the pure chloroxy- 
 naphthalic acid falls as a yellow crystalline powder. 
 
 It is soluble in boiling water, alcohol, ether, and benzine. It dissolves 
 without decomposition in concentrated sulphuric acid, from which it is 
 re-precipitated on the addition of water. It dyes wool an intense red without 
 the aid of a mordant. If chloroxy-naphthalic acid in an alkaline solution is 
 reduced by means of tin powder, and the solution is boiled for fifteen or 
 twenty minutes, a yellow liquid is obtained, which when mixed with ammonia 
 and left to itself, turns green after some time. If it is neutralised with a 
 mineral acid a brown flocculent body is precipitated, which when washed and 
 dried appears as a green powder with a metallic reflection. It is mono- 
 chlorated trioxy-naphthalin. It dissolves in boiling aniline with a red, and in 
 sulphuric acid with a green colour. From the latter solution it is thrown 
 down by water with a violet colour. It dissolves in alcohol with a violet 
 colour, which turns blue on dilution with water. Mono-chlorated trioxy- 
 naphthalin dyes wool and silk a violet, and maybe fixed upon cotton with the 
 aid of albumen. 
 
 25. Ballo's Violet. — Magenta, in the form of acetate of rosaniline, heated 
 with naphthylamin or with bromated naphthalin, gives a fine violet. 
 
 26. Naphthoic Blue. — The attempts made by Girard, and by Mylius, of 
 Dasle, to replace benzoic acid with naphthoic acid in the conversion of 
 magenta into rosaniline blue, have shown that the latter, which is cheaper, 
 gives a blue at least as bright and beautiful as that produced by means of 
 benzoic acid. 
 
 27.— Aniline Grey (Castelhaz). — 
 
 Aniline grey (Gris Castelhaz, p. 210) 1 gallon. 
 
 " Reduction paste," see below 4 gallons. 
 
680 DYEING AND CALICO PRINTING. 
 
 The "reduction paste" is prepared as follows: — 
 
 Acetate alumina i gallon. 
 
 Water i ,, 
 
 Starch 3 lbs. 
 
 Boil till dissolved, cool, and add — ' 
 
 Arsenic solution 1 pint. 
 
 Mix well together. 
 
 The arsenic solution is thus obtained : — 
 
 Glycerin 1 gallon. 
 
 Arsenic 4 lbs. 
 
 Boil till dissolved. 
 
 When printed, the pieces are steamed for thirty minutes. 
 28. Naphthols, or Naphthylic s Alcohols. — If the alkaline salts of sulpho- 
 naphthalic acid are fused with the hydrate of soda we obtain the naphthols, 
 
 Aniline Grey (Castelhaz). 
 
 which bear the same relation to naphthalin as does phenol to benzine. One 
 part of dry sulphonaphthalate of soda is melted in an iron, copper, or silver 
 capsule, with two parts of dry hydrate of soda; the mass is dissolved in 
 boiling water, cooled, and the clear solution decanted, and mixed with hydro- 
 chloric acid. Sulphurous acid is given off, and naphthol is thrown down in a 
 crystalline state. It is filtered, slightly washed, and re-crystallised from 
 boiling water. 
 
 Naphthol a can be sublimed, and crystallises in brilliant white needles, It 
 melts at 94 C, and dissolves readily in alcohol, ether, and benzine, and 
 spaHogly in water. The aqueous solution takes an intense violet colour if 
 mixed with a solution of chloride of lime, and deposits brownish-red flocks if 
 heated. 
 
^^■^^MMI^MMHHHH 
 
 APPENDIX. 681 
 
 Naphthol /3 crystallises in brilliant lamellae, and melts at 122 C. With 
 chloride of lime it takes a yellowish colour, and the liquid, if heated, deposits 
 yellow flocks. In solubility it agrees with the a variety. A chip of pine-wood 
 steeped in the aqueous solution of the naphthols, mixed with hydrochloric 
 acid, and then exposed to sunlight, takes a green colour, which afterwards 
 passes into a brownish-red. The two naphthols, if treated in a dry state 
 with concentrated sulphuric acid, yield sulphonaphtholic acids. If sulpho- 
 naphtholic acid a is mixed with nitric acid a red colouration appears, and 
 binitronaphthol (Martius's yellow) separates. 
 
 Sulphonaphtholic acid (3 does not give this reaction, but naphthol (3 may be 
 converted into binitronaphthol {3 by treating its alcoholic solution with nitric 
 acid. The latter compound crystallises in brilliant yellow lamella?, sparingly 
 soluble in water, readily in alcohol, and very readily in ether and chloroform. 
 Its solutions dye wool and silk a full, beautiful yellow. 
 
 29. Anthracen-Orange. — If binitro-anthraquinon is treated with reducing 
 agents, such as stannite of, soda, sulphuret of antimony, or sulphuret of 
 sodium, it is transformed into a colouring matter, the anthracen-orange of 
 Boettger. It is prepared as follows: — 
 
 The stannite of soda is obtained by mixing with a moderately concentrated 
 soda-lye a clear saturated solution of the protochloride of tin, containing as 
 little free acid as possible. It is poured in a slender stream into the lye, with 
 constant stirring, until a slight turbidity begins to appear in the liquid. It is 
 then left to settle, protected as far as possible from contact with the air, and 
 the clear portion is decanted through a filter. With this the binitro- 
 anthraquinon — washed and still damp — is drenched. A beautiful and in- 
 tensely green liquid is immediately formed, and if boiled without interruption 
 anthracen-orange separates in abundance, after a short time, as flocculent 
 powder, of a cinnabar-red. If this colour is moistened with water, dried, and 
 submitted to sublimation in a porcelain crucible placed in a sand-bath, it fuses 
 at 235 C, and from that point to 260 it sublimes in crystals of a garnet-red, 
 with a green metallic reflection. 
 
 Its best solvents are acetic ether, aceton, chloroform, aldehyd, ether, 
 alcohol, and wood-spirit. It is slightly soluble in bisulphide of carbon, but is 
 insoluble in petroleum and naphtha. At ordinary temperatures it dissolves in 
 sulphuric acid (full strength) without decomposition, even at a boiling heat, 
 forming a brownish-yellow liquid, which, if largely diluted with water, 
 deposits a flocculent mass of a fine red colour. It dissolves also without 
 decomposition, at common temperatures, in nitric acid of specific gravity 1-2. 
 But if heated for some time with a solution of mercuric nitrate it is trans- 
 formed into a deep violet powder, which dissolves" in ether with the same 
 colour. If, instead of heating the original green liquid obtained on treating 
 binitro-anthraquinon with stannite of soda, it is immediately poured into 
 dilute sulphuric acid, a flocculent reddish-brown precipitate is formed, which 
 if filtered, washed, and dried, and then dissolved in alcohol, leaves, after 
 removal of the alcohol, a brown colouring matter, which dissolves in acetic 
 ether with a deep purple-red colour. 
 
 If a solution of anthracen-orange in ether is treated with nitrous acid, a 
 fine powder of a violet-brown is deposited, easily soluble not only in alcohol, 
 but also in water, with a fine deep violet-red colour. If the dry powder is 
 heated to about 68 C. it detonates. 
 
 ^ WW 
 
m ht iv I**** 
 
 682 
 
 DYEING AND CALICO PRINTING. 
 
 If binitro-anthraquinon is boiled for a long time with aniline, the latter 
 takes a deep red-brown colour, and the whole dissolves in hot water with the 
 same colour. If, instead of water, hydrochloric acid is employed, the liquid 
 is coloured at first a dirty yellow, then a red, with the formation of black 
 resinous flocks, which dissolve in bisulphide of carbon with a splendid 
 magenta colour. This colour cannot be withdrawn from the sulphide of 
 carbon either by pure or by acidulated water. 
 
 Binitro-anthraquinon reads energetically upon cyanide of potassium, 
 forming, according to circumstances, violet-brown or orange-red compounds. 
 If, according to Bcettger and Petersen, binitro-anthraquinon is dissolved in 
 16 or 18 parts of concentrated sulphuric acid, and if heat is applied, at about 
 the temperature of 200° C, there is an abundant disengagement of sulphurous 
 acid, and the colour of the liquid changes from a yellowish-brown to a deep 
 red-brown. The reaction becomes more and more brisk, so that it is necessary 
 to withdraw the heat for some time. When the violence of the action has 
 ceased heat is again cautiously applied, until the escape of sulphurous acid 
 has discontinued. 
 
 The mass is allowed to cool, and is thrown into cold water, when it deposits 
 deep reddish-brown flocks, which, after being filtered and washed, dissolve in 
 dilute alkaline solutions with a deep violet-blue colour, and are re-precipitated 
 on the addition of an acid. This substance may be purified by re-crystallisa- 
 tion from alcohol, when it is obtained in small agglomerated granules of a 
 deep violet, or in brilliant incrustations of a brownish-violet with metallic 
 reflections. This colour is sparingly soluble in water, to which it imparts the 
 colour of peach-blossom. It dissolves freely in alcohol, ether, and glycerin, 
 forming solutions of a splendid violet-red. It dissolves in acetic acid with a 
 magenta-red, in sulphuric acid with a hyacinth-red, and in alkaline solutions 
 with a violet-blue. It dyes cotton a violet, without mordants. 
 
 30. Artificial Isopurpurin. — This isomer of purpurin has been recently 
 discovered by Auerbach in the product prepared by Gessert Bros., of Eberfeld, 
 under the name of alizarin, with a yellow reflection, or purpurin, because it 
 produces — both in dyeing with an aluminous mordant and as a steam-colour 
 in printing— shades similar to those obtained with the natural purpurin from 
 madder (see p. 247). 
 
 This so-called yellow alizarin or artificial purpurin appears in form of a 
 slightly liquid homogeneous paste, containing 15 per cent of dry matter, and 
 soluble in dilute caustic alkaline lyes, yielding a solution of a splendid 
 reddish-violet colour. 
 
 To extract isopurpurin from this substance it is dissolved in ammonia, the 
 solution is mixed with hydrate of baryta, and the precipitate formed is boiled 
 with water as long as the filtered liquid has a red colour. From this aqueous 
 solution the isopurpurin is precipitated with an acid, filtered, washed, and the 
 same treatment is repeated. If the isopurpurin is precipitated with sulphuric 
 acid, it may be isolated by treatment with alcohol, the precipitate composed of 
 sulphate of baryta and of isopurpurin. The latter dissolves very readily. 
 
 Isopurpurin prepared in this manner, repeatedly purified with hydrate of 
 baryta and crystallised from alcohol, has the same composition as the purpurin 
 from madder. 
 
 Isopurpurin is of an orange-red, and presents all the properties of alizarin, 
 but it dissolves in the hydrate of soda with a more violet-red colour. It is 
 
APPENDIX. 
 
 683 
 
 readily soluble in alcohol, and moderately soluble in boiling water, from which 
 it separates on cooling. It does not melt at 360 , but it begins to sublime at 
 that temperature. In caustic alkalies it dissolves with a violet-red colour. 
 In ammonia it dissolves with a reddish-brown. The solution in alkaline car- 
 bonates is likewise red, but with a decided brown shade. It is but very 
 sparingly soluble in a saturated and boiling solution of alum. The liquid 
 takes a yellowish-red tint, but without presenting in a high degree that beau- 
 tiful red fluorescence which characterises similar solutions of purpurin. On 
 cooling, the dissolved colouring matter is almost entirely separated out again. 
 The barytic lake, of a violet red, is easily soluble in boiling water. The lime 
 lake, which is of the same colour, is very sparingly soluble. 
 
 An alcoholic solution of isopurpurin, if examined in the spectroscope, shows 
 bands of absorption in the orange and the green, and a faint one in the yellow. 
 If the liquid is too concentrated all the spectrum disappears except the red. 
 
 On mordanted cotton isopurpurin gives shades similar to those produced by 
 purpurin ; the reds and roses border upon a scarlet ; the violet is' brownish ; 
 the browns and blacks are full; and all these colours resist boiling soap-lyes. 
 
 31. Anthrapurpurin. — We have already given (p. 327) a brief notice of the 
 anthrapurpurin discovered by Mr. W. H. Perkin. We add the following par- 
 ticulars : — Crude artificial alizarin is dissolved in a dilute solution of carbonate 
 of soda, and the liquid is agitated with alumina recently precipitated. The 
 alizarin combines with the alumina to form a lake, whilst the anthrapurpurin 
 remains in solution. The precipitate is filtered off, the filtrate heated to 
 ebullition, and mixed with hydrochloric acid. The colouring matter thus 
 thrown down is filtered, washed, and dried. 
 
 The anthrapurpurin obtained by this process is still very impure, containing 
 anthraflavic acid and a substance which gives an orange colour with mordants 
 of alumina. These impurities are in great part removed by repeated boiling 
 in alcohol, in which anthrapurpurin is but slightly soluble. To obtain an 
 absolutely pure product, the best method is to digest the substance with a 
 boiling alcoholic solution of soda. The sparingly soluble soda-compound 
 formed is collected upon a filter, and repeatedly washed with a dilute alcoholic 
 solution of soda. The residue is then dissolved in water, boiled, and the 
 colouring matter is precipitated by chloride of barium. The purple compound 
 thus obtained is collected upon a filter, washed several times with hot water, 
 and finally decomposed by boiling with carbonate of soda. The purple 
 solution is filtered, and from the filtrate the anthrapurpurin is precipitated 
 with hydrochloric acid. It is collected upon a filter, well washed, dried, and 
 finally crystallised twice from glacial acetic acid, when it separates in orange 
 needles. If boiled with alum it yields no special reaction, whilst its isomer, 
 purpurin, yields a violet, fluorescent solution. From isopurpurin, with which 
 it presents certain analogies, it is distinguished by its sparing solubility in 
 alcohol, in which isopurpurin dissolves freely. 
 
 32. Aurin (Yellow Corallin, Rosolic Acid) is pronounced by Dale and 
 Schorlemmer to be a mixture of different bodies. To prepare this substance 
 in a state of purity the commercial product is dissolved in boiling alcohol, 
 and alcohol saturated with ammoniacal gas is added. A crystalline compound 
 of aurin and ammonia, almost insoluble in alcohol, separates out, whilst the 
 impurities remain in solution. The precipitate is washed in alcohol and 
 
fl» i »iM < ~ ifcftifl 
 
 684 
 
 DYEING AND CALICO PRINTING. 
 
 exposed to the air, when the ammonia evaporates and pure avtrin remains. 
 Aurin, heated to 180 C. with alcoholic ammonia, yields red corallin. 
 
 According to H. Fresenius, the rosolic acid obtained by Caro and Wanklyn, 
 on treating an acid solution of a salt of rosaniline with nitrous acid and 
 boiling the residue, is not identical with the phenol-rosolic acid. He pro- 
 poses for it the name of pseudo-corallin. 
 
 33. Derivatives of Resorcin. — If resorcin is heated to 795° C. with 
 anhydrous phthalic acid, we obtain fiuoresceine. It crystallises from alcohol 
 in small deep brown crystals. If thrown down by acids from its potassic 
 solution it takes the form of a brick-red powder. With ammonia it yields a 
 red solution, which even when very dilute displays a magnificent green 
 fluorescence. Fiuoresceine dyes wool and silk a fine yellow without mordant. 
 
 In alkaline solution it is converted by zinc powder into colourless 
 fiuoresceine, which recovers its colouration under the influence of oxidising 
 agents. If heated strongly with sulphuric acid and poured into water, it gives 
 rise to a red deposit, which dissolves in alkalies with a blue colour, and is 
 rendered blue by zinc-powder. The red liquid may be used for dyeing blue on 
 the principle of the indigo-vat, but the colour is neither beautiful nor fast. 
 Fiuoresceine is in many respects analogous with litmus. 
 
 34. Derivatives of Hydroquinon. — If hydroquinon is heated to 130 to 
 140° C. with concentrated phthalic acid two products are formed : the 
 phthalein of hydroquinon, which is colourless, and an isomer of alizarin, of 
 a red colour, to which Grimm has given the name quinizarin. 
 
 To obtain the latter body the product of the reaction of phthalic acid 
 and sulphuric acid is dissolved in alcohol, and water is added, when quini- 
 zarin is deposited in orange flocks, which when dried at ioo° to no C. 
 become red and crystalline. The ethereal and sulphuric solutions present a 
 yellowish green fluorescence, similar to that of the munjistin of Stenhouse. 
 
 Grimm suggests that munjistin and quinizarin bear the same relation to 
 each other as do purpurin and alizarin. Quinizarin melts at 192° to 193° C, 
 and sublimes in feathery crystals. Its solution in the alkalies is blue ; its 
 ammoniacal solution and that formed with alkaline carbonates is more violet. 
 It gives a blue-violet compound with magnesia, and a red-lake with alumina. 
 
 Quinizarin may be easily confounded with alizarin, and dyes mordanted 
 cotton in the same manner. 
 
 35. Derivatives of Pyrocatechin.— If pyrocatechin is heated with 
 anhydrous phthalic acid and with sulphuric acid, on adding water a greenish 
 liquid is produced, which with potash gives a blue colouration that soon 
 disappears. Baeyer thinks that this substance may be analogous tc the 
 colouring matter of logwood. 
 
 36. Gallein. — This colouring matter has been noticed on p. 508. The 
 following additional particulars may be useful. Gallein dyes tissues mor- 
 danted with alumina and oxide of iron in the same manner as the red woods, 
 but the shade is rather more blue. The colours are intermediate between those 
 of peachwood and logwood. It is extremely probable that gallein belongs to 
 the family of the tinctorial wood pigments, and that it is the first member of 
 the series which has been artificially prepared. 
 
 Gallin produces the same shades as gallein, and shows a marked analogy 
 with haematoxylin. 
 
APPENDIX. 
 
 685 
 
 37. Nitrous Derivatives of Resorcin. — By the action of nitrous acid 
 upon resorcin Weselsky has obtained colouring matters which in their 
 brilliance and beauty rival the finest of the aniline colours, and which display 
 phenomena of fluorescence in a splendour far surpassing all bodies previously 
 observed. One of these compounds is formed by passing a current of nitrous 
 acid into an ethereal solution of resorcin. It forms brown crystalline grains 
 with a green metallic lustre, sparingly soluble in water, and rather more 
 soluble in alcohol and acetic acid. Its solutions are of a deep cherry-red 
 colour. In alkaline liquids it dissolves with a rich violet-blue. If the above 
 substance is treated with concentrated nitric acid, with the aid of heat we 
 obtain nitrate of tetrazoresorcin in fine garnet-red crystalline needles of great 
 brilliance. They dissolve in water, ether, and alcohol with a pure indigo-blue 
 colour. The discovery of a cheap souice of resorcin is needed to render these 
 colours practically available. 
 
 38. Cyanin. — 1 part of cinchonine or quinoidine is mixed with 3 parts of 
 hydrates of potash or soda, and as much water as would be needed to dissolve 
 the alkali with the aid of heat, and the mixture is distilled in an iron retort. 
 Along with the watery vapours an oily liquid passes over and settles to the 
 bottom of the water. This is crude chinoline, and amounts in quantity to 
 65 per cent of the cinchonin used. After removal of the water the chinoline is 
 rectified. The portion passing over between 216 to 360 C. is suitable for the 
 preparation of cyanin. 
 
 For a purple shade of cyanin 1 part of chinoline is mixed with ii parts 
 iodide of amyl. The mixture is brought to a boil, when it gradually takes a 
 deep brown colour, and on cooling becomes a crystalline brown mass of 
 hydriodate of amyl-chinoline. The product of the reaction is boiled for ten 
 minutes with six times its weight of water, and when dissolved the liquor is 
 filtered while still boiling. 
 
 The filtrate is placed in a boiler of enamelled iron, brought gradually to a 
 boil, and mixed by degrees with an excess of ammonia. The boiling may be 
 kept up for some hours with advantage, but the evaporated liquid must be 
 replaced with a mixture of equal parts of common ammonia and distilled 
 water. After boiling the mixture is allowed to cool, when the colouring 
 matter is almost entirely precipitated, the supernatant liquor retaining scarcely 
 a trace of colour. The whole is then filtered to separate the colouring matter, 
 which dissolves in alcohol with a fine blue purple colour. 
 
 To prepare cyanin the following process may be employed. The brownish 
 black crystalline mass above mentioned is moistened with five or six times 
 its weight of boiling water, boiled for some time, and filtered. Upon the 
 filter there remains a tarry mass, which dissolves in alcohol with a bright red 
 colour, and may be employed as magenta. The filtrate is of a yellowish 
 green colour and milky appearance. It is heated to boiling and mixed with 
 a lye of caustic soda or potash containing one-fifth of its weight of the solid 
 alkaline hydrate. The lye is added by degrees to the liquid, which is kept at 
 a gentle boil until a quantity of alkali has been introduced equivalent to 
 three-quarters of the iodine contained in the iodide of amyl employed. After 
 boiling fifteen to thirty minutes, during which the liquid takes first a brick 
 colour and then a green, leaflets of a deep blue colour begin to fall, and unite 
 to a black resinous mass, which is cyanin. The colouring matter is filtered 
 and washed with water, in which it is almost insoluble. If the filtrate is 
 
686 DYEING AND CALICO PRINTING. 
 
 brought again to a boil, and if the remaining fourth part of the caustic-lye is 
 added, a black mass is thrown down, which is also cyanin, but which contains 
 all the red colouring matter. This red would have been mixed with the whole 
 of the cyanin if the total caustic-lye equivalent to the iodine of the iodide of 
 amyl had been added at once. The last black precipitate dissolves readily in 
 alcohol, forming a splendid purple-red solution. If this purple alcoholic liquid 
 is filtered, there often remains on the filter a deep coloured mass, which 
 dissolves in benzol with a fine emerald-green colour. The crude precipitate 
 of cyanin dissolves in alcohol with a splendid blue colour, and can be 
 crystallised from the solution. 
 
 According to the researches of Hofmann, Madler, and Merz, cyanin is not 
 a simple substance, but a mixture of at least two homologous bodies, the one 
 derived from chinoline, and the other from lepidine. 
 
 These two cyanins are very similar in their properties, and the colours 
 which they produce upon textile fibres may be considered identical. The 
 cyanin manufactured and sold by Mueller, of Basle, is chinolin-cyanin, whilst 
 that of Menier, of Paris, is lepidin-cyanin, containing mere traces of chinoline. 
 
 In purity and beauty the blue shades produced by cyanin, especially upon 
 silk, are unsurpassed. By artificial light they appear of a splendid violet. 
 Unfortunately the colour is exceedingly fugitive, being destroyed in a few 
 hours by exposure to the direct rays of the sun. No method of overcoming 
 this drawback has yet been discovered, and in consequence cyanin has 
 gradually disappeared from the market. 
 
 39. Dalleiochin (Quinine Green). — This colour has never become an article 
 of commerce. It is prepared as follows : — 
 
 Sulphate of quinine 10 parts. 
 
 Water 1000 ,, 
 
 Liquid chloride of lime 134 ,, 
 
 Hydrochloric acid 35 1, 
 
 These substances are allowed to react upon each other, and 125 parts o»f 
 liquid ammonia are added. A greenish resinous matter is thus precipitated 
 and is collected upon a filter. Quinine green is insoluble in water, benzol, 
 and ether, but it dissolves in alcohol, wood-spirit, and glycerin. Acetic acid 
 turns it to a blue shade : the mineral acids dissolve it with a brown colour, 
 but on neutralisation the original colour is restored. Salt of tin decolourises 
 the solutions. The alcoholic solution diluted with water dyes silk a green, 
 which retains its tone by artificial light. Wool is dyed like silk. Cotton requires 
 to be animalised with albumen. For printing, quinine green is mixed with 
 albumen and the colour fixed by steaming. The shades produced are fan- 
 inferior to thosp obtained with the aldehyd and iodine greens. 
 
 40. Aloes.— The following particulars may be superadded to the information 
 found on p. 417 : — 
 
 Pure aloetic and chrysammic acids are not commonly employed in dyeing 
 and printing, but mixtures of these acids. In preparing the colour by Sacc's 
 process, the solution of aloes in nitric acid is poured in a very slender stream 
 into cold water. Lindner heats in the water-bath 1 part of aloes with 60 
 parts of nitric acid until red vapours come off, and introduces then by degrees 
 g parts more of aloes into the solution, evaporating to dryness when the 
 reaction is over. The resulting mass, which is of a gold-yellow, is washed 
 
APPENDIX. 
 
 687 
 
 on a filter and dried. The yield is 66 per per cent of the weight of the 
 crude aloes employed. The aqueous solution is used directly for dyeing. 
 Lowe digests without heat 1 part of aloes in 8 parts of nitric acid, and after 
 having filtered the solution pours it into a large quantity of water. He also 
 prepares chrysammic acid by evaporating a solution like the above down to 
 one-half. He then adds £ part of nitric acid, and concentrates afresh till 
 crystals of oxalic acid appear, when he pours the whole into a large amount 
 of waiter. 
 
 If instead of proceeding as above the concentrated nitric solution is mixed 
 with excess of ammonia and the whole evaporated to crystallisation, chrysammid 
 is obtained in small brilliant crystals. 
 
 A cheaper preparation may be made by dissolving 132 parts of aloes in 
 100 parts of boiling water and adding 80 parts of nitric acid. There is a 
 brisk effervescence and a plentiful disengagement of gas. The acid is then 
 neutralised with about 10 parts of soda-lye, of sp. gr. 1*12. Before making 
 use of this preparation the mixture is slightly acidulated with hydrochloric 
 or tartaric acid. The action of any deoxidising agent, especially proto- 
 chloride (muriate) of tin changes red chrysammic acid and violet chrysammid 
 into blue h)'dro-chrysammid. All the shades produced upon silk, wool, or 
 cotton, ranging from red to violet or to cinnamon-brown are, in contact with 
 reducing agents, converted to grey, blue-grey, greyish blue, olive-green, or 
 moss-green. If silk and wool are plunged into a weak aqueous solution of 
 chrysammic acid, and the bath is raised to a boil, the silk takes shades varying 
 from rose to corinthe (a colour somewhat approaching that of dried currants), 
 whilst wool is dyed a chestnut-brown, varying in intensity. Cotton unmor- 
 danted is not dyed; if prepared with alumina it takes a violet. If mordanted 
 with iron it remains undyed. Linder's aloetic acid produces upon wool, un- 
 mordanted, a deep brown, which may be carried to a velvety black. Lowe's 
 imperfect chrysammic acid yields upon wool reddish-brown shades. Linder's 
 aloetate of soda (aloetic acid neutralised with soda) imparts to wool, un- 
 mordanted, a fine bluish-grey colour. 
 
 Chrysammid dyes silk and wool a grey, light or dark ; with the addition of 
 pink-salt the tone becomes greenish. 
 
 Upon silk chrysammid dyes a nut-brown ; upon wool a yellow before 
 steaming, and an olive-green after this operation. 
 
 When perchloride of tin is added we obtain a rusty yellow upon cotton, 
 and a cinnamon-brown upon silk and wool. 
 
 With alum chrysammid yields, before steaming, a rusty yellow or buff upon 
 silk and cotton, and a yellow upon wool. After steaming the cotton becomes 
 a pearl-grey, the silk a drab, and the wool a bright " wood " colour. 
 
 According to Lindner, aloetic acid (aloes purple) is useful for fixing colours 
 which in themselves are deficient in solidity. If, for instance, 10 parts of 
 orchil are mixed with £ part of aloes purple, previously dissolved in soda-lye, 
 the colour of the orchil is unaffected by air and light, without any injury to 
 its brightness. If in dyeing cotton goods with madder or fleur de garance a 
 little aloes be added to the bath, the garnet-brown shades acquire a peculiar 
 lustre. 
 
 41. Rufigallic Acid. — Gallic acid can be transformed into tannin by 
 boiling with a very small quantity of arsenic acid, which undergoes no 
 
- ^Wjtog k.hm i i»> i - it ri+fa **i ,, 
 
 688 DYEING AND CALICO PRINTING. 
 
 alteration. Both tannin and gallic acid, if heated to 70 or 8o° C. with con- 
 centrated sulphuric acid, yield by degrees a deep purple solution. This, 
 poured into excess of water, deposits a 'reddish-brown powder, which is 
 thrown upon a filter and freed from sulphuric acid by washing ; 5 parts of 
 sulphuric acid are required to 1 part of gallic acid or 1 of tannin. The pro- 
 duel, which amounts to 66 per cent of the original matter, is rufigallic acid. 
 It dissolves in sulphuric acid ; with strong alkaline lyes it takes an indigo- 
 blue, and it forms a blackish-blue potash salt. In dilute lyes it dissolves with 
 a violet colour ; but it gradually separates out from the solution. If moistened 
 with ammonia it takes a red colour. It dyes cotton goods mordanted with 
 alumina and salts of iron in the same manner as alizarin. The shades are 
 perfectly proof against soaping, but they are dull and deficient in purity. 
 
 Adulteration of Albumen. 
 Albumen is often adulterated with gum, dextrin, and starch. To detect 
 these impurities 1 oz. of the sample is dissolved in lukewarm water. After 
 some time the mass is stirred. If the liquid contain many white clots the 
 quality is inferior; that shows that a notable quantity of the albumen has been 
 coagulated by the employment of too high a temperature during evaporation. 
 The solution is mixed with acetic acid, and some alcohol is added to the 
 decanted acid liquid. If gum is present a precipitate is formed. Starch may 
 be detected by adding a solution of iodine in water, which gives a blue-black 
 colour. If the albumen contains sugar it is easily recognised by means of 
 Fehling's test. 
 
 Dyeing Aniline Blacks on Cotton Yarn. 
 This process requires great care to prevent the blacks from becoming uneven 
 and clouded. The cotton yarn, previously well boiled out, receives seven 
 turns in a bath composed of 200 grms. of sulphate of copper for every kilo, of 
 material dissolved in water slightly acidulated with hydrochloric acid. It is 
 then well wrung out. Next it receives five turns at 50° C. in a bath con- 
 taining 50 grms. hydrosulphate of soda per litre of water, and is next rinsed. 
 It then receives seven turns in a bath of 10 litres of water, 180 grms. chlorate 
 of potash, and 170 grms. of sal-ammoniac dissolved with the aid of heat, and 
 then mixed with 480 grms. chloride of aniline. It is then stretched out very 
 regularly in a hot drying-room at 24' C. for forty-eight hours. It then receives 
 four turns at 30 C. in a bath containing 1 grm. bichromate of potash per 
 litre, and is well rinsed and dried. If the blacks have a reddish tone they 
 may be passed through a bath containing 1 litre of bleaching-liquor at 6° 13. 
 to 100 litres of cold water. 
 
 Printing-ink for Use in Calico-Printing. 
 The following mixture gives fine blacks in the pigment-style : — 
 
 Venice turpentine g parts. 
 
 Soft potash soap 10 ,, 
 
 Olein 4 ,, 
 
 Lamp-black 6 ,, 
 
 Bleu de Paris . . . . 1 part. 
 
 Oxalic acid o - 5 ,, 
 
 Water 1 ,, 
 
»sss»»» 
 
 APPENDIX. 689 
 
 The turpentine is first heated along with the olein ; then the soap is placed on 
 a levigating-slab, and the mixture of turpentine and olein is gradually incor- 
 porated with it. When this is complete the lamp-black, previously ground 
 and sifted, is worked in. Lastly, the Paris blue is gradually ground in, and 
 the oxalic acid and water, which are previously mixed and slightly warmed. 
 The Paris blue and oxalic acid may be replaced with a neutral extract of 
 indigo. 
 
 New Iron Mordant. 
 Dissolve — 
 
 Chromate of potash , 200 grms. 
 
 Oxalic acid 200 „ 
 
 Green vitriol .. .. 6 kilos. 
 
 Water 6 litres. 
 
 New Aniline Red. 
 Acetate of aniline is mixed with ammoniacal oxide of copper and saturated 
 with sulphuric acid, when a fine purple-red colour is developed. After con- 
 centration the liquid, on standing, deposits crystals of sulphate of ammonia, 
 which are filtered off. The new aniline red remains then transparent. 
 
 Printing Aniline Colours on Calico. 
 A solution of gelatin is prepared, containing 50 grms. to the litre of water. 
 Solution of bichromate is then added, drop by drop, till a straw-colour is pro- 
 duced. The aniline colour is then added, and the mixture thickened with 
 dextrin or torrefied starch. After printing, the pieces are exposed for some 
 hours to light, which renders gelatin insoluble when in contact with chrome. 
 The gelatin may be replaced by a solution of casein in a small quantity of 
 ammonia. 
 
 Use of Epsom Salts in Dyeing. 
 In dyeing wool for goods which are required to be " milled " the addition of 
 Epsoms gives greater permanence to the aniline colours, especially Primula 
 and methyl violets. The addition of sulphurous acid is also advantageous. 
 
 Test for Saffranin. 
 If a few particles of the suspected colour are mixed with 2 drops of con- 
 centrated sulphuric acid in a porcelain capsule, and stirred, a splendid blue 
 colour immediately appears. The addition of 2 drops of water converts the 
 blue to an emerald-green. 
 
 Cochineal-Red on Cotton. 
 To 10 lbs. of the yarn, &c, take 10 ozs. of tannin, and dissolve it completely 
 in boiling water. Steep the goods over-night in this liquid. Prepare some 
 red liquor at 12 Baume, and put into a small tub a sufficient quantity to work 
 2 lbs. of cotton yarn. Work the yarn for ten minutes. Fill up the red liquor 
 to its original quantity, and work 2 lbs. more, and so on until the whole of the 
 cotton has been mordanted. It is then allowed to dry, with frequent turning. 
 Piece-goods are winced for an hour in red liquor of the same strength. When 
 
 2 Y 
 
6go 
 
 DYEING AND CALICO PRINTING. 
 
 dry, the goods are passed through a boiling bath containing i lb. prepared 
 chalk to every 10 lbs. of cotton, and washed twice: i to ij lb. of cochineal 
 is extracted in water, the bath is heated to 122° F. with the addition of a little 
 flavin, and the goods are worked therein, the temperature being slowly raised 
 to the boiling-point. 
 
 Method of Determining Anthracen. 
 
 Dissolve 1 grm. of the sample of commercial anthracen in question in 45 cubic 
 centimetres of glacial acetic acid, at the boiling-point, in a small flask. The 
 solution, if needful, is filtered while boiling, and a solution of 10 grms. of 
 chromic acid in 5 cubic centimetres of water and 5 cubic centimetres of 
 glacial acetic acid, the liquid being kept at a gentle boil. The addition of 
 this mixture is continued till a distinct and permanent yellowish-green colour 
 appears, or till, after prolonged boiling, a drop of the liquid placed upon a 
 clean silver coin produces a reddish spot. The whole is then diluted with 
 150 cubic centimetres of water, filtered after standing some hours, and the 
 precipitate (chinon) is washed upon the filter, first with water, then with hot 
 and very dilute potash-lye, and then again with water. It is next dried at 
 212 F., and weighed. After weighing, the chinon is removed from the filter, 
 and the latter is weighed again. Thus the nett weight of the anthrachinon 
 is obtained, to which o*oi grm. must be added, that quantity having been 
 dissolved and removed by the above-directed quantity of acetic acid and water. 
 Commercial chromic acid, it must be remembered, often contains lead. 
 
 New Class of Colouring Matters. 
 Croissant and Bretonniere have patented a process for converting certain 
 organic bodies into colouring matters. The process is applicable not merely 
 to tannin, aloes, starch, and horn, which have a certain value, but to waste 
 worthless bodies, such as moss, cellulose, sawdust, humus from decayed wood, 
 &c. The principle employed is the dehydrogenation of the bodies by the 
 action of sulphur at an elevated temperature, which the authors believe 
 replaces the hydrogen. If it is required to convert bran into colouring matter 
 it is placed in a small iron vessel, covered with a lid. Caustic soda and flower 
 of sulphur are added in certain proportions, and the whole is made up into an 
 homogeneous paste. The vessel is then placed in a furnace where it can be 
 heated to 250 to 300 C. Sulphuretted hydrogen is given off in abundance. 
 When the mixture is dry we find in the vessel, after cooling, a black, friable 
 matter, perfectly soluble in water, to which it imparts a fine sap-green. The 
 solution has a strong affinity for fibres, which it dyes without a mordant. 
 One and the same body gives various tones of colour, according to the propor- 
 tions of the mixture and the temperature applied. Certain substances— such 
 as extracts of dye-woods, aloes, &c— are converted at boiling-point, whilst 
 woody fibre, bran, &c, require a higher temperature. 
 The following examples may be useful : — 
 
 i- Aloes 3 kilos. 
 
 Soda-lye, at 40° Baume 10 litres. 
 
 Water i 
 
 Flower of sulphur 3 kilos. 
 
APPENDIX. 
 
 691 
 
 The mixture is boiled, and yields a lilac-grey. At higher temperatures a deep 
 brown is produced. 
 
 2. Humus >. 20 kilos. 
 
 Normal sulphide 40 litres. 
 
 This "normal sulphide" contains 70 litres soda-lye at 40° B., 65 litres of 
 water, and 30 kilos, of sulphur. To dye cotton, a sufficient quantity of the 
 product is dissolved in water at 60° C, and the goods are worked in this in 
 the usual manner. They are then passed through boiling bichromate of pot- 
 ash solution, which fixes the colour. 
 
 Vat-Blue Ground, with a Red, Brown, Black, and White Pattern. 
 
 The goods are bleached, freed from chlorine with " antichlor," stiffened, 
 and calendered. They are then printed with the following colours : — 
 
 For white: — 10 parts verdigris are stirred up in acetic acid, the mixture 
 diluted with water, and 4 lbs. of pipe-clay are well beaten up in this liquid. 
 As soon as the whole is thoroughly incorporated 1 lb. of powdered gum arabic 
 is added, allowed to dissolve, well stirred up, and water added sufficient to 
 bring it to the consistence required for printing: \ lb. of blue vitriol and 
 ij ozs. tartaric acid are then stirred in. 
 
 For the red : — 2 lbs. pipe-clay are beaten up in red liquor at io° Baume ; 
 I lb. of ground gum arabic is added, and the mixture is allowed to stand at a 
 gentle heat till all is dissolved ; 3 ozs. of powdered blue vitriol are then well 
 stirred in, and, lastly, a solution of 2 ozs. of verdigris in the smallest possible 
 quantity of strong acetic acid. The whole is well stirred up, and is ready 
 for use. 
 
 For a chocolate-brown: — Add to the mass, as directed for red, I lb. of iron 
 liquor at io° B. 
 
 For the black: — Dissolve \ lb. of solid logwood extract in 6 lbs. of boiling 
 water; cool, strain, and dissolve in the clear liquid \ lb. of blue vitriol ; 10 ozs. 
 of powdered gum arabic are added, and the mixture is allowed to stand, with 
 frequent stirring, till the gum is completely dissolved ; 2 ozs. of verdigris are 
 then dissolved in the smallest possible quantity of boiling acetic acid; the 
 solution is added to the mixture, and 6 ozs. of iron liquor at 12 B. are finally 
 stirred in. 
 
 These four colours are blocked in or printed with the perrotine, and the 
 pieces are hung up for four days. They are then vatted to the shade desired, 
 care being taken not to remove the resists by friction. The pieces are then 
 passed through a dung-bath at 167 F., 15 to 20 lbs. of dung being allowed to 
 each piece. Finally, the goods are dyed either with madder or artificial 
 alizarin, the latter requiring no clearing. If alizarin is preferred, ij lbs. of 
 the paste are used along with 1 litre of bran. If madder is used, 6 lbs. are 
 required along with 3 lbs. bran and i£ lbs. sumac. After dyeing, the goods 
 are passed through a boiling bran-bath, rinsed, passed through weak chloride 
 of lime, rinsed again, and dried. 
 
 Black and White on a Madder-Red Ground. 
 The pieces, duly bleached, are padded with red liquor at 12 Baume, and 
 dried at 66° F. After hanging three days they are printed with the following 
 mixtures : — 
 
: $ bmr # >w, m: ++ii ^ mm ^* m ■ 
 
 692 DYEING AND CALICO PRINTING. 
 
 Black.— 
 
 Gum tragacanth 12 ozs. 
 
 Starch 1 lb. 
 
 Glue 8 ozs. 
 
 Boil up to a paste in water, and add — 
 
 Iron liquor 3 litres. 
 
 Nitrate of iron 1 litre. 
 
 Make up the whole with water to 6 litres. 
 Discharge White. — 
 
 Gum tragacanth 12 ozs. 
 
 Starch 1 lb. 
 
 Glue 8 ozs. 
 
 Boil up to a paste, and add — 
 
 Citric acid 2 lbs. 
 
 The pieces are then aged, dunged, rinsed, and dyed up in madder, taking 
 10 lbs. madder and 2 lbs. chalk per 60 yards. After dyeing, the goods are 
 passed through a chlorine bath, taking 1 lb. chloride of lime for the abeve 
 quantity. The pieces are then rinsed, passed through muriatic sours at 
 i° Baume, and rinsed again. If, after rinsing, the goods are still acid, they 
 are passed through a chalk bath, and rinsed again. 
 
 Dark Spirit Violet on Cotton Warps. 
 
 First Method, with Logwood. —Soften ? lb. gum tragacanth in water, and 
 let it swell up to a jelly. Meantime dissolve \ lb. logwood extract in boiling 
 water. Mix both solutions, make them up to 10 litres, boil, and stir till cold. 
 Into the mixture stir \ lb. of crystallised bichloride of tin (perchloride), and 
 add finally ij ozs. bichromate of potash in powder. The mixture is ready for 
 use after being well stirred. The printed yarns are exposed to the air for a 
 day, and are then rinsed without steaming. 
 
 Second Method, with Aniline Colours. — Soften 2 lbs. casein in water at 
 167 F., adding \ lb. liquid ammonia. Dissolve 1 oz. aniline violet and i oz. 
 crude magenta in water; mix with the casein, make up to 10 litres, and add 
 4 ozs. powdered bichromate of potash. The mixture can be used immediately 
 for printing. The printed yarns are dried in the sun, and rinsed. For a darker 
 shade more bichromate is required. 
 
 Blackley Orange is the trade name of a coal-tar colour manufactured by 
 the well-known firm Levinstein and Sons, of Manchester. It is easily soluble 
 in hot water. For printing on woollens or silks a concentrated solution in 
 water is employed, without the addition of acids or mordants In dyeing it 
 is applied at a boiling-heat, with a slight addition of tartaric or acetic acid, or 
 of the chloride of zinc. Large additions of acid destroy the colour. Blackley 
 orange resists the action of the atmosphere better than most coal-tar colours, 
 and its brightness is not injured by soap-lyes, warm or cold. 
 
 Dale's Patent Process for Printing and Dyeing with Aniline Colours. 
 
 First Method, applicable to Goods which are Printed in all Mauve, or have 
 only very little Black. — The goods are bleached as if for the best madder- 
 work, and printed with the following mixture. In machine-printing particular 
 attention must be paid to have the colour-boxes quite clear, and especially free 
 
APPENDIX. 
 
 693 
 
 4 gal. 
 4 .. 
 
 from iron. The contact of iron must be avoided all through the process, or 
 
 the colour will become a drab. 
 
 Dark Shade for two Mauves, or 20 W. Mauve. — 
 
 Gum Senegal water (10 lbs. per gallon) 4 gal- 
 Water J „ 
 
 Tannic acid (pure) 20 ozs. 
 
 Light Shade for two Mauves, or 3 W. Mauve. — 
 
 Gum-water 
 
 Water • • 
 
 Tannic acid 3 ozs. 
 
 Dark Shade for three Mauves, or 24 \V. Mauve. — 
 
 Gum-water J gal. 
 
 Water 1 ,, 
 
 Tannic acid , 24 ozs. 
 
 Medium Sliade for three Mauves, or 10 W. Mauve. — 
 
 Gum-water i gal. 
 
 Water 1 „ 
 
 Tannic acid 10 ozs. 
 
 The colour for covers is 2, 2 1 , or 3 ozs. per gallon of gum-water. 
 
 Dissolve the tannin in the water, and add to the gum-water. Sighten the 
 dark shades with a little ground indigo, and the light ones with a little mauve 
 or magenta. After printing age one night, or run the goods through the 
 ageing-machine and let lie one night. Steam forty-five minutes, at 1 lb. 
 pressure to the square inch. The goods are then ready for fixing. For the 
 fixing process a wooden beck is divided into two parts: the first part is lined 
 with lead, and contains a closed leaden steam-coil to heat the fixing liquor; at 
 the end of esich division is a pair of weighted rollers, to squeeze back as much 
 as possible of the liquid : the second part of the beck contains cold water for 
 rinsing. The first part of the beck is made up as follows : — 
 
 Water 1 gal. 
 
 Tartar emetic 2 ozs. 
 
 Glue \ oz. 
 
 The beck is filled three-fourths with this liquor, and heated from 170 to 
 190° F. Lower temperatures must be carefully avoided. The pieces travel 
 through this liquid in three-quarters of a minute. The goods are well washed, 
 and are then ready for dyeing. 
 
 For dyeing twenty pieces, 9/8, '25 yards each, put sufficient water in the 
 beck, enter the pieces, raise the temperature to 120 F., add one quart of acetic 
 acid at 8° Tw., and 20 ozs. of mauve paste, previously dissolved in 1 quart 
 methylated spirit. Raise the temperature to a boil in seventy-five minutes, 
 and boil fifteen to twenty minutes. Without the final boiling the whites will 
 be soiled and the colours flat. Wash well, and dry. To clean the whites 
 pass open through chloride of lime, — 1 quart at io° Tw., mixed with 18 gals, 
 of water. Put in a beck containing 5 lbs. soap to 500 to 600 gals, water, and 
 boil for eight to ten minutes ; wash well, and finish. 
 
 For magentas the mordant and subsequent treatment are the same, and the 
 goods are dyed up as follows :— For twenty pieces, 98, 25 yards, enter the 
 
BBBBBBWHWWiWiliBli ■ ***# ! - 
 
 694 DYEING AND CALICO PRINTING. 
 
 pieces, and raise the heat to 120 F. ; add 4 lbs. of soap, dissolved in a little 
 water. Dye in the same time and at the same heat as for mauve, and \\a h 
 well. No clearing is generally required, but if the whites are not satisfaifto-y 
 they must be winced in soap, and on no account passed through bleaching- 
 liquor. A wooden dye-beck must be used. 
 
 Second Method, for Single Colour Black and Mauve, or Dark Work. 
 No. 1. Standard for Pale Shades. — 
 
 Gum Senegal water £ gal. 
 
 Water £ „ 
 
 Tannic acid 8 ozs. 
 
 Mauve to shade up to 12 ,, 
 
 No. 2. Standard Medium. — 
 
 Gum-water and water as above. 
 
 Tannic acid 16 ozs. 
 
 Mauve to shade up to 20 „ 
 
 No. 3. Standard, Dark. 
 
 Gum tragacanth water (1 lb. per gal.) i gal. 
 
 Water | „ 
 
 Tannic acid 24 ozs. 
 
 Mauve to shade up to 30 or 35 ,, 
 
 A small quantity of glycerin added to the printing colours is an improvement. 
 Print on madder-bleached cloth, without any further preparation ; age ore 
 night and steam forty-five minutes at 1 lb. pressure to the inch, run through 
 the fixing-beck, wash, and finish. Magenta by this process is not so good as 
 by the former method. 
 
 Artificial Orchil. 
 
 The following process has been patented in France (No. 97,641, Dec, 1872) 
 by Messrs. Vogt and Henninger : — Toluene, or its monochloride or mono- 
 bromide, is treated with concentrated sulphuric acid. To the acid mixture 
 are added lime and carbonate of lime, so as to separate the excess of sulphuric 
 acid as insoluble sulphate of lime. Or, in order to economise sulphuric acid, 
 the acid mixture above mentioned may be allowed to act upon common salt, 
 when hydrochloric acid is given off, and the residue contains sulphate of soda 
 and the compound disulpho- or chloro- or bromosulpho- conjugated acids of 
 toluene. A certain quantity of water is added, and the liquid containing the 
 compound acids is decanted, and neutralised with lime. The solution then 
 contains the disulphotoluate or chloro- or bromo-cresylo-sulphite of lime, 
 which are then transformed into soda-salts by adding sulphate or carbonate of 
 soda. The compound salts, when dry, are melted with double their weight of 
 soda and (or ?) potash, either under pressure or in open vessels, and furnish 
 orcin, and the salicylates and cresylates of soda and (or ?) potash. The re- 
 action is effected at the temperature of 280° or 300 C. 
 
 The melted mass is then dissolved in water, saturated with hydrochloric or 
 sulphuric acid, concentrated, and the alkaline chlorides or sulphates are 
 removed by crystallisation. The mother-liquor contains orcin, which is 
 transformed into orcein by the joint action of ammonia, lime, and atmospheric 
 oxygen. (See p. 375). 
 
APPENDIX. 
 
 695 
 
 Chemical Removal of " Burls " from Wool and Woollen Goods. 
 
 It is well known that the more powerful mineral acids, — especially the sul- 
 phuric, when diluted with water and aided hy the action of heat, attack vege- 
 table matters much more readily than wool. As early as 1853 Fenton and 
 Crom patented the application of this principle for the destruction of cotton 
 contained in the rags of mixed goods. The following year Izart and Lecoup 
 took out a French patent for the application of the same principle to the 
 destruction of the " burls," i.e., fragments of cotton, straw, thistle-seeds, and 
 other vegetable matters entangled in wool. These burls, as is well known to 
 practical men, are a source of considerable trouble. As they do not take the 
 same colours as the wool, they have either to be plucked out of the pieces by 
 hand, with the aid of peculiarly-constructed tweezers, or colour-mixtures — 
 known as " burling-inks " — are applied to the spots with a blunt quill, or — as 
 especially the case with black broadcloths, doe-skins, &c. — the entire pieces 
 have to be " burl-dyed," i.e., submitted to a cotton-dyeing process. 
 
 The procedure of Izart, as modified in accordance with the results of expe- 
 rience, consists in steeping the wool, woollen yarn, or pieces, in a bath of 
 dilute sulphuric acid at 3° to 4° Baume. It is then drained in a centrifugal 
 machine, and finally heated to ioo c C. in a drying-stove, for a suitable time. 
 The burls are thus destroyed, and the wool, being freed from all residual acid 
 by thorough washing, is submitted to the ordinary manufacturing routine. 
 
 An experimental investigation has recently been carried on by Messrs. 
 Duclaux, Lechartier, and Raulin, as to the limits of time, temperature, and 
 concentration, within which this procedure is at once safe and efficacious. It 
 has been proposed to use baths of earthy and metallic salts, zinc, tin, alum, 
 &c, prior to the acid bath, with the notion of protecting the wool against any 
 corrosion or alteration of its properties. Carefully executed experiments 
 proved — as any judicious tinctorial chemist would have anticipated — that 
 these additions had not the slightest effect in protecting the wool, and exerted, 
 further, a very detrimental action on the subsequent dyeing operations. A 
 variety of acids and acid salts, both mineral and organic, also chlorine and its 
 oxygen compounds, were tried in comparison with sulphuric acid. The last- 
 mentioned body, however, was found incontestably preferable. 
 
 Drainage in the hydro-extradtor (centrifugal machine, or " whizzer ") was 
 proved to be quite indispensable. The following table shows the limits of 
 temperature, time, and concentration of acid, within which the operation can be 
 successfully conducted. 
 
 Temperature of 
 Stove. 
 
 Acid for an Exposure of Two Hours 
 in Stove. 
 
 Ditto for Half an Hour 
 in Stove. 
 
 8o° C. 1 1 lit. to 4 4 lit. (per 100 litres water) 3 to 7 litres. 
 
 no 8 C. 1 lit. to 3 lit. „ ,, 1 J lit. to 4 J lit. 
 
 150 C. £ lit. to 1 lit. „ „ 1 Ht. to ij lit. 
 
 Below these limits the burls are not destroyed, whilst above them the wool 
 is attacked, and its affinity for mordants and colours seriously modified. After 
 the stoving, the wool is passed through a weak bath of carbonate of soda, 
 and is then thoroughly rinsed in pure water. 
 
 Corallin. 
 According to the recent investigations of Commaille, corallin is produced 
 between 115 and 150" C, but more rapidly and plentifully at the latter 
 
^, «,« »U 6M , .«, «. »» ■*■' » « **»*« ft »4j W y « M 
 
 696 
 
 DYEING AND CALICO PRINTING. 
 
 temperature, at which 100 parts of phenol yield, in six hours, 26 parts of 
 corallin. From the mother-liquor 72 per cent of the oxalic acid employed can 
 be recovered, whilst the sulphuric acid is found to have totally disappeared. 
 Commaille considers that yellow corallin is not, as commonly supposed, an 
 acid, and that red corallin is not the amid of the yellow. The proportion of 
 oxalic acid employed is far too large. Corallin does not form definite metallic 
 compounds. 
 
 Hydrometer Tables. 
 Baume's scale for liquids heavier than water is graduated from 0° to 72 . Its 
 relation to direft specific gravity is shown in the following table : — 
 
 o° 
 
 = 1 000 
 
 3 
 
 I - 020 
 
 6 
 
 1-041 
 
 9 
 
 I-063 
 
 12 
 
 1-086 
 
 15 
 
 i- 109 
 
 18 
 
 i"i34 
 
 21 
 
 1-160 
 
 24 
 
 ri88 
 
 27 
 
 1216 
 
 3o 
 
 1-246 
 
 33 
 
 1-277 
 
 36 
 
 1-310 
 
 39 • 
 
 1*345 
 
 42 
 
 1-382 
 
 45 
 
 1-421 
 
 48 
 
 1-462 
 
 5i 
 
 i'5°5 
 
 54 
 
 i-55i 
 
 57 
 
 i- 600 
 
 60 
 
 1-652 
 
 63 
 
 1-708 
 
 66 
 
 1-767 
 
 69 
 
 1-831 
 
 72 
 
 1 -900 
 
 The scale for liquids lighter than water extends from io° to 40 , the lowest 
 number representing the specific gravity of water, and the higher ones those 
 of lighter liquids. 
 
 10 
 
 i-ooo 
 
 II 
 
 o'993 
 
 12 
 
 0-986 
 
 13 
 
 0-980 
 
 14 
 
 o - 973 
 
 15 
 
 0967 
 
 16 
 
 0-960 
 
 17 
 
 "'954 
 
 18 
 
 0-948 
 
 19 
 
 0-942 
 
 20 
 
 0-936 
 
 21 
 
 0-930 
 
 22 
 
 o-g24 
 
 23 
 
 0-918 
 
 24 
 
 0-913 
 
 25 
 
 0-907 
 
 26 = 
 
 o-goi 
 
 27 
 
 0-896 
 
 28 
 
 o - 8go 
 
 29 
 
 0-885 
 
 30 
 
 o-88o 
 
 3i 
 
 0-874 
 
 32 
 
 0-869 
 
 33 
 
 0-864 
 
 34 
 
 0-859 
 
 35 
 
 0-854 
 
 36 
 
 0-849 
 
 37 
 
 0-844 
 
 38 
 
 0839 
 
 39 
 
 0-834 
 
 40 
 
 0-830 
 
 Beck's scale, for liquids heavier than water, runs from i°, which is slightly 
 above the specific gravity of water, to 70 . It is a most inconvenient scale. 
 
 1-0059 
 1-0119 
 1-0180 
 1-0241 
 
 5 = 
 
 1-0303 
 
 6 
 
 1-0366 
 
 7 
 
 1-0429 
 
 8 
 
 1-0494 
 

 9° = 
 
 i'°559 
 
 10 
 
 i - o625 
 
 ii 
 
 1 -0692 
 
 12 
 
 I- °759 
 
 13 
 
 1-0828 
 
 14 
 
 1-0897 
 
 15 
 
 1-0968 
 
 16 
 
 1-1039 
 
 17 
 
 i-iiii 
 
 18 
 
 1-1184 
 
 19 
 
 1-1258 
 
 20 
 
 i-i333 
 
 21 
 
 1-1409 
 
 22 
 
 1-1486 
 
 23 
 
 I-I 565 
 
 24 
 
 1-1644 
 
 25 
 
 1-1724 
 
 26 
 
 1 • 1 806 
 
 27 
 
 ri888 
 
 28 
 
 1-1972 
 
 29 
 
 1-2057 
 
 30 
 
 1-2143 
 
 31 
 
 1-2230 
 
 32 
 
 1-2319 
 
 33 
 
 1-2409 
 
 34 
 
 1-2500 
 
 35 
 
 1-2593 
 
 36 
 
 1-2687 
 
 37 
 
 1-2782 
 
 38 
 
 1-2879 
 
 39 
 
 1-2977 
 
 APPENDIX. 
 
 40 = 
 
 f3077 
 
 4 1 
 
 [•3178 
 
 42 
 
 [•3281 
 
 43 
 
 [•3386 
 
 44 
 
 [•3492 
 
 45 
 
 [•3600 
 
 46 ] 
 
 [•3710 
 
 47 
 
 [•3821 
 
 48 
 
 t'3934 
 
 49 3 
 
 •4050 
 
 50 3 
 
 •4167 
 
 5i 
 
 [•4286 
 
 52 
 
 ■4407 
 
 53 
 
 t"453Q 
 
 54 J 
 
 •4655 
 
 55 ^ 
 
 •4783 
 
 56 > 
 
 •4912 
 
 57 > 
 
 '5°44 
 
 58 ] 
 
 •5179 
 
 59 l 
 
 •5315 
 
 60 : 
 
 5454 
 
 61 i 
 
 •5596 
 
 62 
 
 [•5741 
 
 63 ' 
 
 •5888 
 
 64 ] 
 
 •6038 
 
 65 
 
 [•6190 
 
 66 
 
 [•6346 
 
 67 ] 
 
 •6505 
 
 68 ] 
 
 •6667 
 
 69 ] 
 
 •6832 
 
 70 ] 
 
 •7000 
 
 697 
 
 Cartier's scale, for liquids lighter than water, runs from io° = water to 44 
 Its relation to diredt specific gravity is shown in the following table : — 
 
 IO : 
 
 = i-ooo 
 
 II 
 
 0-992 
 
 12 
 
 0-985 
 
 13 
 
 0-977 
 
 14 
 
 0970 
 
 15 
 
 0963 
 
 16 
 
 0-956 
 
 17 
 
 0949 
 
 18 
 
 0-942 
 
 19 
 
 0-935 
 
 20 
 
 0-929 
 
 21 
 
 0-922 
 
 22 
 
 0-916 
 
 23 
 
 0-909 
 
 24° = 
 
 0-903 
 
 25 
 
 0897 
 
 26 
 
 0-891 
 
 27 
 
 0-885 
 
 28 
 
 0-879 
 
 29 
 
 0-872 
 
 30 
 
 0-867 
 
 3i 
 
 0-862 
 
 32 
 
 0-856 
 
 33 
 
 0-851 
 
 34 
 
 0-845 
 
 35 
 
 0-840 
 
 36 
 
 0-835 
 
 37 
 
 0-830 
 

 ■ - 
 
 DYEING AND CALICO PRINTING. 
 
 38° = 
 
 0-825 
 
 39 
 
 0819 
 
 40 
 
 0814 
 
 4i 
 
 0-809 
 
 42° = 
 
 0804 
 
 43 
 
 0799 
 
 44 
 
 0794 
 
 698 
 
 The direct scale of specific gravity assumes water to be 1, or i-ooo, all 
 heavier liquids requiring larger numbers, and all lighter ones numbers smaller 
 than unity. This scale shows at once the weight per gallon of any liquid, 
 the two first figures to the left hand representing pounds avoirdupois, and the 
 two or more following to the right being decimal fractions of a pound. Thus 
 if a sample of double muriate marks 1-450, a gallon of it weighs 144 lbs. 
 
 Twaddell's scale makes water = 0, and the strongest oil of vitriol = 170 . 
 Unlike direct specific gravity, it extends only to liquids heavier than water. 
 For greater accuracy the scale is arranged on a set of six instruments, num- 
 bered progressively upwards. Thus a No. 1 Twaddell ranges from to 32 . 
 
 The relation between Twaddell's scale and direct specific gravity is very 
 simple. To convert a degree of Twaddell into the corresponding degree of 
 direct specific gravity, multiply by 5 and add i-ooo to the product. Thus if a 
 bleaching-liquor marks 7° Tw., its specific gravity is 7 
 
 5 
 
 35 
 
 I '000 
 
 I- °35 
 A sample of single aquafortis marks 33 Tw. Its specific gravity is then — 
 
 33 
 
 165 
 
 I'OOO 
 
 1-165 
 
 If the specific gravity has been taken the degree of Twaddell may be found 
 by reversing this rule, subtracting i-ooo, and dividing the remainder by 5. 
 Thus a sample of double aquafortis marks specific gravity 1-350. Its degree 
 on Twaddell's scale will be — , 
 
 i"350 
 
 i- 000 
 
 5) 350 
 
 70° Tw. 
 In some hydrometers, graduated for direct specific gravity, the first figure 
 is omitted. On such water marks o", and the above-mentioned sample of 
 double aquafortis 350 . A peculiar hydrometer — called the ammonia-glass or 
 ammonia-meter — is used in some districts for the sale of ammonia. It ranges 
 from io G (= water) to 45 , representing the lightest liquors. It very nearly 
 agrees with Baume's light glass. Hydrometers give inaccurate results if 
 applied to — 
 
 a. Hot liquids. 
 
 b. Glutinous liquids, solutions of gum, starch, size, &c. 
 
 c. Effervescing liquids. 
 
 d. Liquids holding solid matters in suspension. 
 
-wamm 
 
 APPENDIX. 
 
 699 
 
 Hot liquids should be allowed to cool, or, if it be necessary to observe their 
 specific gravity at elevated temperatures, a comparative trial should be made 
 on the liquid while hot, and on a portion when cold, so that the indication 
 may be corrected. If it be needful to take the specific gravity of any liquid 
 coming under the heads b, c, and d, a gallon should be accurately weighed. 
 
 In chemical, dye, and print woiks, where hydrometers are placed in the 
 hands of foremen for frequtnt use, they should be regularly brought at some 
 stated time to the laboratory for verification. 
 
 Thermometer Scales. 
 
 To convert Centigrade (Celsius) into Fahrenheit. — If the temperature be 
 above the freezing-point of water (32 F. = o° C), multiply by 9, divide by 5, 
 and add 32 to the quotient. If it be below freezing-point (32° F. = o° C), 
 but above o F. (= — 18 C), multiply by 9, divide by 5, and subtract; the result 
 from 32 . If below - 18 C. (= o° F.), multiply by 9, divide by 5, and sub- 
 tract 32° from the result. 
 
 Reaumur's scale, in which the boiling-point of water is made 80°, and the 
 freezing-point, as in the Centigrade, o°, is still used in many German dye and 
 print works. 
 
 To convert Reaumur into Centigrade, whether above or below freezing-point, 
 multiply by 5 and divide by 4. 
 
 To convert Centigrade into Reaumur, multiply by 4 and divide by 5. 
 
 To convert Reaumur into Fahrenheit, or vice versa, the rules above given for 
 the conversion of Centigrade into Fahrenheit, &c, will apply, 4 being used 
 respectively as multiplier or divisor instead of 5. 
 
 Decimal or " Metric " Weights and Measures. 
 Measures of Length. 
 
 Millimetre = 0-03937 inch. 
 Centimetre = 0-393708 ,, 
 Decimetre = 3-937079 inches. 
 Metre = 39370790 inches. 
 ,, = 3-2808992 feet. 
 ,, = 1-093633 yards. 
 Decametre — 32-808992 feet. 
 Hectometre = 328-08992 ,, 
 Kilometre = 3280-8992 ,, 
 
 ,, = 1093-633 yards. 
 Myriametre = 10936-33 ,, 
 
 ,, = 6-2138 miles. 
 
 English inch = 2-539954 centimetres. 
 ,, foot = 3-0479449 decimetres. 
 ,, yard = 0-91438348 metre. 
 ,, fathom = 1-82876696 metres. 
 „ furlong = 201-16437 . ,, 
 ,, mile = 1609-3149 „ 
 
 Superficial Measures. 
 Square millimetre = B ] 5 of a square inch. 
 >) n = 0-00155 ,, ,, 
 
*4»»W»»" 
 
 .v: 
 
 700 
 
 DYEING AND CALICO PRINTING. 
 
 Square centimetre = 0*155086 ,, ,, 
 
 decimetre — 15-5086 square inches. 
 
 ,, = 0-10769 square foot, 
 
 metre or centiare = 1550-86 square inches. 
 >. 11 = 107698 ,, feet. 
 
 n 1, '— 1-196033 „ yards. 
 
 Are = 1076-98 square feet. 
 „ = 119-6033 „ yards. 
 ,, = 0-098845 rood. 
 Hedare = 11960-33 square yards. 
 
 ,, = 2-471143 acres. 
 Square inch = 645-109201 square millimetres. 
 ,, M = 6-45109 ,, centimetres. 
 
 ,, foot = 9-2905 square decimetres. 
 „ yard — 0-836097 metre. 
 Acre = 0-404671 hedare. 
 
 Measures of Capacity. 
 Cubic millimetre = 0*000061029 cubic inch. 
 ,, centimetre = 0*061029 ,, „ 
 
 ., >i (millilitre) = 15-438395 grain measures. 
 
 10 cubic centimetres = 0-61029 cubic inch. 
 
 >. 11 (centilitre) = 154-38395 grain measures. 
 
 100 cubic centimetres = 6-1029 cubic inches. 
 
 ,, ». (decilitre) = i543'8395 grain measures. 
 
 1000 cubic centimetres = 61-0295688 cubic inches. 
 
 .. ,. (litre) = 15438-395 grain measures. 
 
 i> .> 11 — 1760773 imperial pints. 
 
 n .» 11 = 0-2200967 „ gallon. 
 
 Decalitre = 610-295688 cubic inches. 
 
 ,, = 2 - 2oog668 gallons. 
 He&olitre = 3*5317 cubic feet. 
 
 „ = 22-009688 gallons. 
 
 Cubic metre, stere, or kilolitre = 1*308 cubic yards. 
 
 n .. ». = 35'3 I 7i cubic feet. 
 
 ,> 11 1, = 220*09688 gallons. 
 
 Myrialitre = 353*171 cubic feet. 
 Fluid ounce = 283*384 cubic centimetres. 
 Pint = 0*567932 litre. 
 Quart = 1*135864 litres. 
 Gallon = 4*54345797 litres. 
 Cubic inch = 16-3855 cubic centimetres. 
 ,, foot = 28-3159 ,, decimetres. 
 „ yard = 0*764520695 cubic metre. 
 
 Weights. 
 Milligramme = 0*015438395 grain. 
 Centigramme = 0*15438395 „ 
 Decigramme = 1*5438395 grains. 
 
APPENDIX. 
 
 701 
 
 Gramme = 15*438395 grains. 
 
 ,, = 0-643 pennyweight. 
 
 „ = 0-03216 oz. troy. 
 
 ,, = 0*03527 oz. avoirdupois. 
 Decagramme = i54'38395 grains. 
 
 „ = 5-64 drams avoirdupois. 
 
 Hectogramme = 3-2154 ozs. troy. 
 
 >> = 3*527 ozs. avoirdupois. 
 
 Kilogramme = 2-6803 lbs. troy. 
 
 ,, = 2-2054 lbs. avoirdupois. 
 
 Myriagramme = 26803 lbs. troy. 
 
 „ = 22-05486 lbs. avoirdupois. 
 
 Quintal metric (100 kilos.) = 220-5486 lbs. avoirdupois. 
 Tonne metric (1000 kilos.) = 2205-486 lbs. avoirdupois. 
 Ton = 1015649 kilos. 
 Hundredweight = 50-78245 kilos. 
 Quarter = 12-6956x44 kilos. 
 Pound = 453-4148 grammes. 
 Ounce = 28-3375 
 Dram = 1-77108 ,, 
 
 Pound troy = 373*096 grammes. 
 Ounce „ = 31-0913 „ 
 Pennyweight = 1-55457 ,, 
 Grain = 0*054773 ,, 
 
 Apothecaries' dram = 3-8869 grammes. 
 Scruple = 1*29546 grammes. 
 
'; $tf* .'* *k f*mi<X !iJ* Trtim*i *i> « i^#M^ hmmmki 
 
 (702) 
 
 BIBLIOGRAPHY. 
 
 Coal-Tar. 
 
 Examen des Matieres Colorantes Artificielles derivees du Goudrnn de 
 Houille, par E. Kopp, premiere partie (Extrait du Moniteur Scientifique 
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 lb., seconde partie. 
 
 International Exhibition, 1862. Reports by the Juries. Class II., Sec- 
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 Gaultikr de Claubry. Rapport sur les Etablissements de la Societe de 
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 Odobre, 1862. 
 
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 G. Lunge. Die Destination der Steinkohlentheers und die Verarbeitung 
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 Depouilly Freres. Bulletin de la Societe Industrielle de Mulhouse, 
 
 1865, pp. 217, 299. 
 W. H. Pekkin. Chemical News and Journal of Physical Science, 
 
 vol. xxii. 1870. 
 Th. Chateau. Couleurs d'Aniline, d'Acide Phenique et de Naphtaline. 
 
 Paris, 1868. 
 A. Kekul£. Chemie der Benzolderivate oder der Aromatischen Substan- 
 
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 Exposition Universelle de 1867. Rapports de Jury International, &c, 
 
 t. vii., p. 223. 
 Dr. Max Vogel. Die Entwicklung der Anilin-Industrie. Die Anilin- 
 
 farben, ihre Entstehung, Herstellung und Technische Verwendung. 
 
 Leipzig, 1866. 
 Reimann. Aniline and its Derivatives. English Edition. By William 
 
 Crookes, F.R.S., &c. London, 1868. 
 A. Jordan. Das Anilin und die Anilinfarben. Weimar, 1866. Appen- 
 
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 T. H. Oppler. Theorie und Praktische Anwendung von Anilin. Berlin, 
 
 1866. 
 Girard et De Laire. Traite des derives de la Houille, &c. Paris, 1872. 
 R. Wagner.' Handbook of Chemical Technology. English Edition. By 
 
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BIBLIOGRAPHY. 
 
 703 
 
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 Rosolic Acid, Corallin, &c. 
 
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 t. xxxii., pp. 308, 323. 
 
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 P- 450. 
 
w*!*' 
 
 704 DYEING AND CALICO PRINTING. 
 
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 1862, p. 412. 
 
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 p. 197. 
 
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 19. Kielmeyer. Moniteur Scientifique, Septembre, 1S72, p. 740. 
 
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 21. Reim ann's Farber. Zeit., i87i,pp. iS, 50 (Jaune Campo-Belio). 
 
 Phenicienne and other Phenyl Browns. 
 
 1. Roth. Bulletin de la Societe Industrielle de Mulhouse, 1864, *• xxxiv., 
 
 P- 439- 
 
 2. E. Dolfuss. Rapport sur, &c, id., t. xxxiv., p. 500. 
 
 3. Alfraise. Brevet No. 60,358, du 8 Odlobre, 1863. 
 
 4. Monnet. Bulletin de la Societe Industrielle de Mulhouse, Oclobre, 1861. 
 
 5. Dullo. Deutsche Industriezeitung, 1865, p. 193. 
 
 6. Bolley. Schweiz. Polytechn. Zeitschrift, 1869, p. 140. 
 
 Cresylol. 
 
 1. Williamson and Fairlie. Annal. der Chemie und Pharm., t. xcii., p. 319. 
 
 2. Duclos. Annal. der Chemie und Pharm., t. cix., p. 135. 
 
 3. Ad. Wurtz. Moniteur Scientifique, 1870, p. 547. 
 
 Binitrocresylol. 
 1. Martius et Griess. Zeitschrift der Deutsch. Chemisch. Gesellschaft, 
 1869, p. 206. 
 
 Trinitrocresylol. 
 1. Kellner et Beilstein. Annal. der Chemie und Pharm., t. cxxviii., 
 p. 164. 
 
 Benzol, its Homologues and Derivatives. 
 
 1. Faraday. Phil. Transactions, 1825, p. 440. Poggeiwl. Annal., t. v., 
 
 p. 306. 
 
 2. Mitsckerlicii. Poggcnd. Annal., t. xxi., p. 231. Annal. der Chemie 
 
 und Pharm., t. ix., p. 39; t. xxxi., p. 625 ; t. xxxiii. p. 224; t. xxxv., 
 
 P- 37°- 
 
 3. Hofmann. Annal. der Chemie und Pharm., t. Iv., p. 200. 
 
 4. Warren de la Rue and Muller. Journal fiir Prakt. Chem., t. xxii., 
 
 p. 300. Jahresbericht der Chemie, 1856, p. 606. 
 
 5. Freund. Annal. der Chemie und Pharm., t. cxv., p. ig. 
 
 6. Wohler. Annal. der Chemie und Pharm. t. cii., p. 125. 
 
 7. Mansfield. Chem. Soc. Journ., vol. i., 1849, pp. 244 to 268. Chem. 
 
 Coll. Reports, 1849, pp. 227 to 251. 
 
* -«'• 
 
 
 
 
 8. Church. 
 g. H. Kopp. 
 
 Annal 
 Annal 
 
 BIBLIOGRAPHY. 
 
 der Chemie und Pharm., t. civ., p. in. 
 der Chemie und Pharm., t. xcviii., p. 369. 
 
 705 
 
 Church and Perkin. Journal fur Prakt. Chimie, t. xxxvi., p. 93 ; t. lvii. 
 
 p. 177. 
 Coupier. Bulletin de la Societe Industrielle de Mulhouse, 1869, p. 259. 
 
 13 
 
 Toluol. 
 Pelletier and Welter. Annal. der Chemie und Pharm., t. xxii., p. 150 ; 
 
 t. xxviii., p. 297. 
 Cahours. Pharm. Centralblatt, 1850, p. 344. Annal. der Chemie und 
 
 Pharm., t. lxxvi., p. 286. 
 Deville. Annal. der Chemie und Pharm., t. xliv., p. 305. 
 Volkel. Annal. der Chemie und Pharm., t. lxxxvi., p. 335. 
 E. Kopp. Comptes Rendus, 1849, p. 149. Gmelin, Handb., t. vi., p. 174. 
 Mansfield. Annal. der Chemie urid Pharm., t. lxix., p. 176. 
 Cannizaro. Annal. der Chemie und Pharm., t. xc., p. 252 ; t. xcvi., p. 246. 
 Warren de la Rue and Muller. Journ. fur Prakt. Chemie, t. Ixx., p. 300. 
 C. M. Warren. Zeitschrift fur Chemie, 1S65, p. 666. Journal fur Prakt. 
 
 Chemie, t. xcvii., p. 50. 
 Fittig and Tollens. Annal. der Chemie und Pharm., t. cxxxi., p. 304. 
 Coupier. Bulletin de la Societe Industrielle de Mulhouse, 1864, p. 259. 
 Rosenstiehl. Bull, de la Societe Industrielle de Mulhouse, 1868, p. 194. 
 Berthelot. Bull, de la Societe Industrielle de Mulhouse, 1869, p. 194. 
 
 Xylol. 
 
 1. Cahours. See Toluol. 
 
 2. Volkel. See Toluol. 
 
 3. Warren de la Rue and H. Muller. Journ. fur Prakt. Chemie, t. Ixx., 
 
 p. 300. Annal. der Chemie und Pharm., t. cxx., p. 339. 
 
 4. H. Muller. Zeitschrift fur Chemie, 1864, p. 161. 
 
 5. Beilstein. Annal. der Chemie und Pharm., t. cxxxiii., p. 32. 
 
 6. Fittig. Annal. der Chemie und Pharm., t. cxxxiii., p. 47; t. cxxxvi., 
 
 P- 303- 
 
 7. Be'champ. Comptes Rendus, t. lix., p. 47. 
 
 Cumol. 
 
 1. Gerhardt and Cahours. Annal. der Chemie und Pharm., t. xxxviii., 
 
 p. 88. 
 
 2. Abel. Annal. de Chemie und Pharm., t. lxiii., p. 308. 
 
 3. Mansfield. Annal. der Chemie und Pharm., t. lxix., p. 179. 
 
 4. Mitthausen. Journ. fiir Prakt. Chemie, t. lxi., p. 79. 
 
 5. Church. Journ. fiir Prakt. Chemie, t. lxv., p. 383. 
 
 6. Warren de la Rue and Muller. See Xylen, 
 
 Nitrobenzol. 
 
 1. Mitscherlich. Annal. der Chemie und Pharm., t. xii., p. 305. 
 
 2. Mulder. Journ. fiir Prakt. Chemie, t. xix., p. 375. 
 
 2 z 
 
706 
 
 DYEING AND CALICO PRINTING. 
 
 Binitrobenzol. 
 i. Deville. Journ. fiir Prakt. Chemie, t. xxv., p. 353. 
 2. Muspratt and Hofmann. Annal. der Chemie und Pharm., t. lvii., p. ;i4. 
 
 Nitrotoluol. 
 
 1. Deville. Journ. fiir Prakt. Chemie, t. xxv., p. 353. 
 
 2. Glenard and Boudault. Journ. fur Prakt. Chemie, t. xxxiii., p. 459. 
 
 3. Jaworsky. Zeitschrift fiir Chemie, t. viii., p. 225. 
 
 4. Kekulj?. Zeitschrift fiir Chemie, t. x., p. 225. 
 
 5. F. Beii.stein and A. Kuhlberg. Zeitschrift fiir Chemie, t. xii., p. 521 
 
 Binitrotoluol. 
 
 1. H. Deville. See Nitrotoluen. 
 
 2. CAHOURS. Ccmptes Rendus, t. xxiv., p. 555. 
 
 Trinitrotoluol. 
 1. Wilbrand. Annal. der Chem. und Pharm., t. exxviii., p. 178. 
 
 Nitroxylol. 
 1. Deumelandt. Zeitschrift fiir Chem., 1866, p. 21. 
 
 Industrial Preparation of Nitrobenzol. 
 
 1. Mansfield. Le Technologiste, t. x., 1848. 
 
 2. Collas. Secret des Arts par le Dodteur Quesneville, 185 1, Nos. 5 and 6. 
 
 3. Depouilly Freres. Bulletin de la Societe Industrielle de Mulhouse, 
 
 1865, p. 217. 
 
 4. W. H. Perkin. Moniteur Scientifique, 1869, pp. 145, 209, 257. 
 
 Aniline and its Derivatives. 
 
 1. Unverdorben. Annal. der Physik, t. viii., p. 397. 
 
 2. Fritzsche. Annal. der Chem. und Pharm., t. xxxix., pp. 76, gi. 
 
 3. Runge. Annal. der Physik, t. xxvi., pp. 67, 513. 
 
 4. Zinin. Annal. der Chem. und Pharm., t. xliv., p. 283. 
 
 5. Hofmann. Annal. der Chem. und Pharm., t. xlvii., p. 37 ; t. lii., p. 56; 
 
 t. liii., pp. 1, 57; t. lxvii., pp. 61, 129, 205; t.lxx., p. 129; t. Ixxix., p. 11. 
 
 6. Muspratt and Hofmann. Annal.[der Chem. und Pharm., t. liii., p. 221; 
 
 t. liv., p. 27 ; t. lxii., p. 200. 
 
 7. Bechamp. Ann. de Chimie et de Physique, troisicme serie, t. xlii., p. 186. 
 
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 Zeitschrift fiir Chem., 1864, p. 315. 
 
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BIBLIOGRAPHY. 
 
 707 
 
 16. Berthelot. Annal.de Chim. etde Phys., troisiemeserie, t. xxxviii., p. 63 ; 
 
 t. lviii., p. 446. 
 
 17. Juncadella. Annal. der Chem. und Pharm., t. ex., p. 254. 
 
 18. Ch. Bardy. Monit. Scient., 1870, p. 553. 
 
 Toluidine and its Derivatives. 
 
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 p. 172. 
 
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 Chem., 1865, p. 513. 
 
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 p. 461. Zeitschrift fur 
 
 221. Zeitschrift fur 
 
 Pseudotoluidine. 
 
 1. Rosenstiehl. Bulletin de la Soc. Indust. de Mulhouse, 1868, p. 543. 
 
 2. W. Korner. Compt. Rendus, t. lxviii., p. 824. 
 
 Xylidine. 
 
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 2. Deumelandt. Zeitschrift fur Chem., 1866, p. 21. 
 
 3. C. A. Martius. Monatsbericht der Konigl. Akademie der Wissens- 
 
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 Industrial Preparation of Aniline. 
 
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 6. Brimmeyr. Dingl. Polytechn. Journ., t. clxxvi., p. 462; t. clxxix., p. 388. 
 
 Aniline Colours. 
 
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 2. A. W. Hofmann. See Aniline; also, Compt. Rendus, t. xlvii., p. 472. 
 
 Proceedings of the Royal Society, vol. ix., p. 294. 
 
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 p. 635, Five additions: Oft. 1, Nov. 19, Nov. 26, Dec. 17, 1859, and 
 Feb. 14, i860. 
 
 2Z2 
 
yoB 
 
 DYEINO AND CALICO PRINTING. 
 
 *9 
 
 A. W. Hofmann. Comptes Rendus, t. liv., p. 418. Journ. fur Prakt. 
 
 Chem., t. lxxxviu, p. 226. Comptes Rendus, t. lvi., p. 1033. Zeit- 
 
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 Girard and de Laire. Brevet d'Invention, Feb., 1867. 
 Girard, de Laire, and Chapotaut. Comptes Rendes, t. lxiii., p. 964 ; 
 
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 1869, p. 674. 
 Coupier. Bulletin de la Soc. Industr. de Mulhouse, 1866, p. 259. 
 Schutzenberger. Rapport sur les Procedes Coupier. Bulletin de la 
 
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 Rosenstiehl. Bulletin de la Soc. Industr. de Mulhouse, 1866, p. 264 ; 
 
 1871, p. 217, et Wagner's Jahresbericht, 1871, p. 764. 
 A. W. Hofmann. Rouge de Xylidine, Monatsbericht der Konigl. Akademie 
 
 der Wissenschaften zu Berlin, July 15, 1869. 
 Safranin. Dingler's Polyt. Journ., t. ccii., p. 307. Bulletin de la Soc. 
 
 Chim. de Paris, t., xvi., 1871, p. 383. Wagner's Jahresbericht, 1871, 
 
 p. 772. 
 A. W. Hofmann and A. Geyger. Deutsche Chem. Gesellschaft, t. v., 
 
 pp.462, 526, 1870, Nos. ro, 11. Bulletin de la Soc. Chim. de Paris, 
 
 t. xviii., 1872, p. 279. 
 
 Aniline Blue. 
 
 1. Girard and de Laire. Brevet d'Invention, July 6, i860. Additions 
 
 Jan. 2, 1861. Brevet du Jan. 2, 1861. Moniteur Scientifique, t. v£i., 
 p. 4. Traite des Derives de la Houille, pp. 585, 590. 
 
 2. Beissenhirz. Annal. der Chem. und Pharm., t. lxxxvii., p. 376. 
 
 3. Fritzche. Journ. fiir Prakt. Chem., t. xxviii., p. 202. 
 
 4. E. Kopp. Moniteur Scientifique, t.iii., p. 75. Brevet d'Invention, June 113, 
 
 1861. 
 
 5. BiSchamp. Brevet d'Invention, June 22, i860. Comptes Rendus, t. liii., 
 
 P- 538- 
 
 6. C. Calvert, C. Lowe, and S. Clift. English Patent, June 11, 186*0. 
 
 Brevet Francais, D6c. 12, i860. 
 
 7. G. Sch^ffer and Gros-Renaud. Monit. Scientifique, t. iii.,p. 293. 
 
 8. Ch. Lauth. Moniteur Scientifique, t. Hi., p. 79. 
 
 g. Persoz,de Luynes, and Salvetat. Comptes Rendus, 1861, No. 14, p. 100. 
 Repertoire de Chim. Appliq., t. iii., pp. 131, 170. 
 
 10. BficouRT. Moniteur Scientifique, t. iv., Jan. 1, 1862. 
 
 11. Monnet and Dury. Brevet d'Invention, May 30, 1852. Addition, Aug. 7, 
 
 1862. Addition, October 21, 1862. 
 
BIBLIOGRAPHY. 
 
 709 
 
 12. Nicholson. Moniteur Scientifique, t. vii., p. 5. Patent, July io, 
 
 1862. 
 
 13. Williams. Repertory of Patent Inventions, March, 1864. 
 
 14. Hofmann. Comptes Rendus, 1864, t. lix., p. 793. 
 
 15. Collin. Brevet d'Invention, May 16, 1862. 
 
 16. Girard, de Laire, and Chapotaut. Brevet d'Invention (Girard and de 
 
 Laire), March 21, 1866; Certificat d'Addition, March 16, 1867. 
 
 17. Bolley. Schweiz. Polytechn. Zeitschrift, 1863, p. 32. 
 
 18. Blumer-Zweifel. Moniteur Scientifique, 1869, p. 301. 
 
 19. E. Willm. Bulletin de la Societe Industrielle de Mulhouse, Nov., 1861. 
 
 20. J. Persoz. Brevet au nom de MM. Guinon, Marnas, et Bonnet, July, 
 
 1862. 
 
 21. Richard. Moniteur Scientifique, 1862, p. 463. 
 
 22. Bulk. Deutsche Chem. Gesellschaft, t. v., p. 417; 1872, No. 9. Bulletin 
 
 de la Soc. Chim., t. xviii., 1872, p. 277. 
 
 Girard and de Laire. 
 Girard and de Laire. 
 Girard and de Laire. 
 Girard and de Laire. 
 
 io. 
 11. 
 
 12. 
 
 13- 
 14. 
 
 15- 
 16. 
 
 17' 
 
 18. 
 19. 
 20. 
 21. 
 22. 
 
 23- 
 24. 
 
 Aniline Violet. 
 Brevet d'Invention, Jan. 2, 1861. 
 Brevet d'Invention, Feb. 21, 1867. 
 Brevet d'Invention, Feb. 25, 1867. 
 Traite des Derives de la Houille, p. 595. 
 E. C. Nicholson. English Patent, June 20, 1862. 
 Delvaux. Brevet d'Invention, March 28, 1862. Certificat d'Addition, 
 
 OcL 10, 1862. 
 Wise. Le Technologiste, Aug., 1865. 
 Poirrier and Chappat. Brevet d'Invention, June 16, i860. Certificat 
 
 d'Addition du Aug. 11, 1866. 
 Ch. Lauth. Moniteur Scientifique, 1864, p. 336. Brevet d'Invention, 
 
 December 1, 1866. 
 Wanklyn. Brevet d'Invention, Nov. 6, 1865. 
 
 Perkin. Provisional English Patent, August 27, 1856; completed 
 Feb. 2, 1858. Brevet Francais, Feb. 20, 1858. English Patent, Sept. 10, 
 1864. 
 Scheurf.r-Kestner. Bulletin dela Soc. Industr.de Mulhouse, June, i860. 
 A. Schlumberger. Bulletin de la Soc. Industr. de Mulhouse, March, 1862. 
 Tabourin and Franc. Brevet d'Invention, Aug. 6, 1858. 
 Greville Williams. English Patent, April 30, 1859. 
 Kay. English Patent, May 9, 1859. 
 D. Price. English Patent, May 25, 1859 ; Brevet Francais, Nov. 16, 
 
 1859. 
 Guigon. Brevet Francais, May 30, 1861. 
 Ch. Lauth. Le Technologiste, Nov., 1861. 
 Levinstein. Brevet d'Invention, Sept. 2, 1864. 
 Bolley. Schweiz. Polytechn. Zeitschrift, 1858. 
 Beale and Kirkham. English Patent, May 13, 1859. 
 Depouilly et Lauth. Brevet d'Invention, Jan. 19, i860. 
 R. Smith. Provisional Protection, March 15, i860. Final Specification, 
 
 Aug. 17, i86o._ 
 
•^ffitfiffim ■ huf * t *t h*pW*( 
 
 4 ^i^4^m^» » $WC£ *£ ■ 
 
 710 
 
 DYEING AND CALICO PRINTING. 
 
 25. Coblentz. Brevet d'Invention, March 23, i860. 
 
 26. J. Dale and H. Caro. English Patent, May 26, i860. 
 
 27. G. Philipps. Brevet d'Invention, Jan. 28, 1864. 
 
 28. Perkin. Annal. der Chemie und Pharm., t. cxxxi., p. 201. Patent, 
 
 1864. 
 
 29. Bulk. See Aniline Blue. 
 
 30. A. W. Hofmann. Berichte der Deutsch. Chem. Gesellschaft, fie annee^ 
 
 p. 263. Moniteur Scientifique, Mai, 1873. 
 
 Note d'un Manufacturier, 
 
 Aniline Green. 
 
 1. Usebe. Brevet d'Invention, Oct. 28, 1862. 
 
 Moniteur Scientifique, vol. vi., p. 361. 
 
 2. Lucius. Polytechn. Centralblatt, 1864, pp. 1596, 1659. 
 
 3. Lauth. Brevet d'Invention, December 28, 1865. 
 
 4. Wanklyn and Paraf. English Patent, Aug. 14, 1866. 
 
 5. Keisser. Brevet d'Invention, April 18, 1866. 
 
 6. A. W. Hofmann. Monat&bericht des Konigl. Akademie der Wissen- 
 
 schaften zu Berlin, July 15, 1869. 
 
 7. A. Poirrier, C. Bardy, and Ch. Lauth. Bulletin de la Societe Chim. de 
 
 Paris, t. xv., 1871, p. 156. Dingl. Polytechn. Journ., t. cxcviii., p. 94. 
 Wagner's Jahresbericht, 1870, p. 587. 
 
 8. Girard and de Laire. Traite des Derives de Houille, p. 608. 
 
 Aniline Brown and Yellow. 
 
 1. H. Kcechlin. Bulletin de la Soc. Industr. de Mulhouse, Aug., 1865. 
 
 2. J. Fayolle. Brevet d'Invention, Nov. 15, 1864. Moniteur Scientifique, 
 
 t. vii., p. 417.. 
 
 3. Girard and de Laire. Brevet d'Invention, March 23, 1863. . 
 
 4. Hunt. Sillim. Amer. Journal, No. 1849. 
 
 5. A. W. Hofmann. Annal. der Chem. und Pharm., t. lxxv., p. 356. 
 
 6. A. Mathiessen. Annal. der Chem. und Pharm., t. cviii., p. 212. 
 
 7. Luthringer. Brevet d'Invention, Aug. 30, 1861. 
 
 8. Mene. Comptes Rendus, t. Hi., p. 311. 
 
 9. A. Schultz. Le Technologiste, Jan., 1866. 
 
 10. H. Caro and P. Griess. Zeitschrift fur Chemie, t. x., p. 278. 
 
 11. C. A. Martin and P. Griess. Zeitschrift fur Chemie, t. ix., p. 132. 
 
 12. H. Schiff. Journ. der Chem. und Physik, 1864, p. no. Le Techno- 
 
 logiste, oa., 1863. 
 
 Aniline Black and Grey. 
 
 1. Lightfoot. Brevet d'Invention, Jan. 28, 1863, No. 57,192. English 
 
 Patent, Jan. 17, 1863. 
 
 2. Cordillot. Moniteur Scientifique, t. vi., p. 569 (1864). 
 
 3. Ch. Lauth. Bulletin de la Soc. Chim. de Paris, Dec, 1864, Fevr., 1866, 
 
 May 20, 1873. 
 
 4. C. Kcechlin. Moniteur Scientifique, t. vii., p. 772. 
 
 5. Rosenstiehl. Bulletin de la Soc. Industr. de Mulhouse, 1865, Nov. et 
 
 Dec, p. 436. 
 
BIBLIOGRAPHY. 
 
 7" 
 
 6. J. Persoz. Deutsche Industrie-Zeitung, 1868. 
 
 7. Coupier. Brevet d'Invention, Sept. 17, 1867. 
 
 8. Castelhaz. Brevet d'Invention, Oct. 19, 1865, No. 69,083. 
 
 9. C. Hartmann. Grothe's Muster-Zeitnng, No. 33. Dingler's Journal, 
 
 ccii., p. 389. Wagner's Jahresbericht, 1871, p. 761. 
 10. A. Muller. Chem. Centralblatt, 1871, p. 288. Wagner's Jahresbericht, 
 
 1871, p. 775. 
 n. Jakasson and Muller-Pack. Moniteur de la Teinture, Oct. 20, 1872. 
 
 Bulletin de la Soc. Chim. de Paris, t., xix., 1873, p. 285. 
 
 12. J. Persoz. Moniteur Scientifique, 1872, p. 396. 
 
 13. M. Vogel. Muster-'Zeitung, 1868, No. 9. Becker und Reimann, 
 
 Anilin-Farberei, Berlin, 1871, p. 26. 
 
 Naphthalan and its Derivatives. 
 
 1. E. Kopp. Examen des Matieres Colorantes Artificielles Derives du 
 
 Goudron de Houille, Seconde partie, Couleur de Naphthaline. (Extrait 
 du Moniteur Scientifiqae du Docteur Quesneville). 
 
 2. Ballo. Das Naphtalin und seine Derivate in Beziehung auf Technik 
 
 und Wissenschaft, Brunswick, 1870. 
 
 3. Th. Chateau. Couleurs d'Aniline, d'Acide Phenique, et de Naphthaline, 
 
 Paris, 1868. 
 
 4. Berthelot (Formation of Naphthaline). Will's Jahrb., 1866, p. 516, 
 
 1S67, 186S. 
 
 5. Vohl (Preparation of Naphthaline). Dingl. Journ., t., clxxxvi., p. 138. 
 
 6. Kolbe (Constitution). Annal. der Chem. und Pharm., t. lxxvi,, p. 40. 
 
 7. Erlenmeyer (Constitution). Annal. der Chem. und Pharm., t. cxxxvii., 
 
 p. 346. 
 
 8. Gr<ebe (Constitution). Annal. der Chem. und Pharm., t. cxlix., p. 25. 
 
 9. Faust and Saame (Chlorures de Naphtaline). Zeitschrift fiir Chem., 1869. 
 10. Glaser (Derives Bromes). Annal. des Chem. und Pharm., t. cxxxv.,p. 40. 
 ii. Roussin (Nitronaphtaline). Comptes Rendus, t. lii. Dingl. Journ., t. 
 
 clxi., p. 69. 
 
 12. Newton (Naphtaline Yellow). Patente, Dingl. Journ., t. clxxi., p. 72. 
 
 13. Dusart (Acide Nitroxynaphtalique). Comptes Rendus, t. lii., p. 1183, 
 
 1861. Journ. fiir Prakt. Chem., t. lxxxiv., p. 188. 
 
 14. E. Kopp (ib.). Repert. de Chim. Appliq., 1861, pp. 262, 306, 405. 
 
 15. Darmstadter and Wichelhaus (Binitronaphtaline). Berl. Bericht, 1869, 
 
 p. 274. 
 
 16. Laurent (ib.). Annal. de Chim. et de Phys., t. lix., p. 381. 
 
 17. Troost (ib.). Bullet, de la Soc. Chim. de Paris, 1861, p. 74. 
 
 18. Roussin (Naphtazarine). Comptes Rendus, t. lii., p. 1034. 
 
 19. Liebermann (ib.). Berl. Ber., 1870, p. 905. 
 
 20. Aguiar and Baeyer (ib.). Berl. Ber., 1871, pp. 251,301, 438. 
 
 21. Carev Lea (Reduction of Binitronaphtaline). Dingl. Journ., t. clxvi., 
 
 PP-3I7. 237- 
 
 22. Troost (ib.). Bulletin de la Soc. Chimique de Paris, 1861, p. 74. 
 
 23. Mi'lhauser (ib.). Annal. der Chem. und Pharm., t. cxli., p. 240. Will's 
 
 Jahrb., 1865, p. 528, 1866, p. 619. 
 
fit 
 
 DYEING AND CALICO PRINTING. 
 
 24. Zinin (Naphtylamine). Annal. der Chem. und Pharm., t. xliv., p. 283. 
 
 25. Carey Lea (ib.). Dingl. Journ., t. cxvi., p. 237 ; t. clxxiii., p. 480 ; t. cxc, 
 
 p. 428. 
 
 26. Piria (Naphtazarine). Annal. der Chem. und. Pharm., t. lxxviii., p. 62 ; 
 
 t. ci., p. 92. 
 
 27. ScHEURER-KESTNERand Richard (Violet de Naphtylamine). Dingl. Journ. r 
 
 t. clxii., pp. 295, 193. 
 
 28. Clavel (Rouge de Naphtylamine). Dingl. Journ., t. cxl., p. 428. 
 
 29. Church and Perkin (Nitrosonaphtyline). Chem.Centralblatt, 1S56, p. 604; 
 
 1863, p. 913. 
 
 30. Martius (Jaune de Martius). Dingl. Journ., t. clxxxvii., p. 165. 
 
 31. Wichelhaus and Darmstadter (ib.). Berl. Ber. 1S69, p. 113. 
 
 32. E. von Sommaruga (Indophane). Deutsche Chemische Gesellschaft, 
 
 t. iv.. p. 94, 1871. Bulletin de la Soc. Chim., 1871, t. xxv., p. 2S1. 
 Wagner's Jahresbericht, 1871, p. 750. 
 
 33. Hofmann (Rouge de Naphtaline). Berl. Ber., 1S69, pp. 374, 412. Dingl. 
 
 Journ. t. cxlii., p. 513. 
 
 34. Zinin (Naphtalidam). Journ. fur Prakt. Chem., t. xxxvii., p. 29; t. lvii., 
 
 P- x 73- 
 
 35. D'Aguiar (ib.). Berl. Ber., 1870, p. 27. 
 
 36. Gr^be (Naphtoquinones). Annal. der Chem. und Pharm., t. cli., p. 1. 
 
 Berl. Ber., 1869 p. 612. 
 
 37. Dlpouilly (Acide Cbloroxynaphtalique). Bulletin de la Soc. Chim., 
 
 1865, p. 10. 
 
 38. Merz (Acide Sulfonaphtalique). Zeitschrift fi'ir Chem., 1868, pp. 34, 393. 
 
 39. Merz and Mulhauser (Cyannaphtaline). Zeitschrift fur Chem., 1869, 
 
 pp. 70, 614. 
 
 40. Wichelhaus and Darmstadter (ib.). Berl. Ber., 1869, p. 356. 
 
 41. Grieff (Naphtol). Chem. Centralblatt, 1863, p. 125. 
 
 42. Schaffer (ib.). Berl. Ber., 1869, p. 90. Zeitschrift fur Chem., i86g, 
 
 p. 215. 
 
 43. Laurent (Acide Phtalique). Revue Scientifique, t. xiv., p. 560. 
 
 44. Vohl (ib.). Annal. des Chem. und Pharm., t. ~xliv., p. 71. 
 
 Anthracen and its Derivatives. 
 E. Kopp (Sur l'Anthraccne et ses Derives). Moniteur Scientifique, i86g, 
 
 t. xi., pp. 465, 851, 873, 1065,1138; 1870, t. xii., p. 753 ; 1871, t. xiii., 
 
 pp. 531, 691 ; 1872, t. xiv., pp. 33, 252, 319, 681 ; 1873, t. xv., p. 14. 
 G. Auerbach. Das Anthracen und seine Derivate. Berlin, 1873. 
 Dumas and Laurent (Paranaphtaline). Annal. de Cbim. et de Phys.., 
 
 troisieme serie, t. 1., p. 187. 
 Laurent (Anthracene). Annal. de Chim. et de Phys., troisieme serie, 
 
 t. lx., p. 230 ; t. lxvi., p. 148 ; t. lxxii., p. 415. 
 Fritzsche [ib.). Journ. fur Prakt. Chem., t. lxxiii., p. 282; t. cv., p. 129. 
 
 Rep. Cbim. Prat., 1862, t. iv., p. 269. Bulletin de la Soc. Chim., t. vi ., 
 
 p. 474 ; t. viii., p. 191 ; t. xii., p. 414. 
 Anderson (Anthracene and its Derivatives). Annal. der Chem. und Pharm.., 
 
 t. cxxii.. p. 294. 
 
BIBLIOGRAPHY. 
 
 7*3 
 
 7. Berthelot (Formation de l'Anthracene). Bulletin de la Soc. Chim., 
 
 t. vi., pp. 268, 272, 2S0 ; t. vii., pp. 43, 224, 274, 279, 288; t. viii., 
 pp. 195, 225, 231 ; t. ix., p. 295 ; t. x., p. 483. 
 
 8. Gr^ebe and Liebermann (Anthracene and its Derivatives). Annal. der 
 
 Chem, und Pharm., 1S70, t. vii. (Supplement), p. 257. Bed. Ber., 
 1870, pp, 634, 637. Bulletin de la Soc. Chim. t. xi., pp. 178, 271, 516. 
 
 9. Liebermann (Anthraquinone). Bed. Ber. 1871, pp. 109, 230. 
 
 10. Greiff (Preparation de l'Anthracene). Dingi. Journ., t. cxciii., p. 511 ; 
 
 t. cxciv., p. 351. 
 
 11. Gessert (ib.). Polytechn. Notizbl., 1870, p. 221. 
 
 12. Schuller (ib.). Bed. Ber., 1870, p. 548. 
 
 13. Wart ha (Anthraquinone). Bed. Ber., 1870, p. 548. 
 
 14. Bolley (Nitroanthracene). Bed. Ber., 1871, p. 671. 
 
 15. ,, (Alizarine). Schweiz, Polytechn. Zeitschrift, 1869, p. 145 ; 
 1870, pp.31, 51. 
 
 16. Perkin (Derivatives of Anthracene and Anthraflavine). Chemical News, 
 
 vol. xxi., pp. 116, 139; vol. xxii., pp. 37, 283 ; vol. xxiv., p. 226. Journal 
 of the Chemical Society (3), t. viii., p. 133 ; t. ix., p. 25. 
 
 17. Bottger and Petersen (Derives de l'Anthraquinone). Bed. Ber., 1871, 
 
 pp. 226, 301. 
 
 18. Bottger (Orange d'Anthracene). Polytechn. Notizblatt, 1870, p. 225. 
 
 19. Roscoe (Alizarin). Chemical News, 1870, vol. xxi., p. 185. 
 
 20. Dale and Schorlemmer (Alizarine). Bed. Ber., 1870^.838. 
 
 21. Schunck (Anthraflavine). Bed. Ber., 1871, p. 359. 
 
 22. Strecker (Nitroxyalizarine). Zeitschrift fur Chem., t. iv., 1S68, p. 263. 
 
 23. Limpricht (Formation de l'Anthracene). Bulletin de la Soc. Chim., 
 
 t. vi., p. 467. 
 
 24. Auerbach (Isopurpurine). Moniteur Scientifique, Aug. 1872, p. 686. 
 
 Das Anthracen und seine Derivate, Berlin, 1873, p. 122. 
 
 25. W. H. Perkin (Anthrapurpurine). Bulletin de la Soc. Chim., t. xviii., 
 
 1872, p. 527; t. xix., 1873, p. 519. Moniteur Scientifique, September, 
 
 1873, p. 788. 
 
 26. H. Grothe (Printing with Alizarine). Grothe's Muster-Zeitung, 1871, 
 
 No. 21, p. 142; No. 30, p. 242; No. 46, p. 362. 
 
 Colours Derived from Phenol. 
 
 1. Dale and Schorlemmer (Rosolic Acid). Bed. Ber., 1871, pp. 231, 968. 
 
 Bulletin de la Soc. Chim., 1871, t. xvi., p. 374. Chemical News, 
 vol. xxvii., p. 103. Bulletin de la Soc. Chim., September 20, 1873. 
 
 2. H. Fresenius (ib.) Journ. fur Prakt. Chem. t. iii., p. 477. Bulletin de 
 
 la Soc. Chim., 1871, t. xvi., p. 375. 
 
 3. Baeyer (Colours derived from Phenols). Bed. Ber., 1871, pp. 457, 555, 
 
 658. Bulletin de la Soc. Chim., t. xvi., 1871, pp. 184, 377. 
 
 4. F, Grimm (Phtaleine de l'Hydroquinone et Quinizarine). Deutsche 
 
 Chemische Gesellschaft, t. vi., p. 506, 1873. Bulletin de la Soc. Chim., 
 Odobre 5, 1873. 
 
 5. Weselsky (Nitro-Derivatives of Resorcin). Berl. Ber., 1871, p. 613. 
 
 Bulletin de la Soc. Chim., 1871, t. xvi., p. 186. 
 
^ alRyMl ^i M c^< *OM*hN 
 
 
 714 
 
 DYEING AND CALICO PRINTING. 
 
 Cyanin. 
 
 1. Runge (Leucoline). Poggend. Annal. der Phys., t. xxxi., p. 68. 
 
 2. Hofmann (ib.). Annal. der Chem. und Pbarm., t. xlviii., p. 27. 
 
 3. Gf.rhardt (Chinoline). Revue Scientifique, t. x., p. 186. 
 
 4. Greville-Williams (Chinoline Bluej. Chemical News, vol. ii., i860, 
 
 p. 219. 
 
 5. Hofmann (Cyanine). Dingl. Polytechn. Journ., 168, p. 125. Comptes 
 
 Rendus, t. lv., p. 84. 
 
 6. Schnitzer (ib.). Chem Centralb., 1861. p. 636. 
 
 7. Nadler and Merz (ib.). Journ. fur Prakt. Chem., t. c, p. 129. 
 
 8. Schonbein (ib.). Journ. fur Prakt. Chem., t. cv., pp. 385, 449. 
 
 9. Horace Kochlin (Cinchonine). Repertoire de Chim. Appliq., 1861, t. iii., 
 
 p. 381. 
 10. H. Kochlin (Dalleiochine). Bulletin de la Soc. Industrielle de Mulhouse, 
 i860, t. xxx., p. 458. 
 
 Colours Derived from Aloes. 
 
 1. Schunck (Acide Chrysamique). Annal. der Chem. und Pharm., t. xxxix., 
 
 p. 1 ; t. lxv., p. 235. 
 
 2. Mulder (ib.). Annal. des Chem. und Pharm., t. lxviii., p. 329; t. lxxii., 
 
 p. 285. 
 
 3. Laurent (ib.). Compte Rendu des Travaux de Chimie, 1850, p. 163. 
 
 4. C. Robiquet (Aloes et Derives). Annnal. des Chem. und Pharm., t. lx., 
 
 p. 295. 
 
 5. Sacc (Dyeing with Derivatives of Aloes). Dingl. Journ., t. cxxxiv., 
 
 p. 289. 
 
 6. Boutin (ib.). Le Teinturier, p. 355. 
 
 7. Lindner (ib.). Dingl. Journ., t. cxxxv., p. 312. 
 
 8. Lowe (ib.). Dingl. Journ. t. cxxxvii., p. 238. 
 
 9. Stenhouse and Muller (Chrysammic Acid). Zeitschrift fiir Chem., 
 
 1866, p. 565. 
 
 10. Finck (Acide Chrysocyamique). Zeitschrift fiir Chem., 1865, p. 519. 
 
 11. Tilden (Chrysammic Acid and Aloi'n). Chemical News, 1872, t. xxv., 
 
 pp. 229, 244. 
 
 Rufigallic Acid. 
 
 1. Lowe (Acide Rufigallique). Journ. fiir Prakt. Chem., t. cvii., p. 296. 
 
 2. Malin (ib.). Annal. der Chem. und Pharm., t. cxxxi., p. 345. 
 
 3. Jaffe (ib.), Berl. Ber., 1870, p. 694. 
 
 4. Hugo Schiff (ib. et Acide Tannique). Berl. Ber., 1871, pp. 231, 968. 
 
 Bulletin de la Sec. Chim., 1871, t. xvi., p. 198. 
 
 Murexide. 
 
 1. Prout (Purpuric Acid). Annal. of Philos., vol. xiv., p. 363. 
 
 2. Liebig and Wohler (Murexide). Annal. des Chem. und Pharm., t. xxvi., 
 
«■■ 
 
 BIBLIOGRAPHY. 
 
 715 
 
 3. Braun ^Preparation de l'Acide Urique). Dingl. Journ. t. clii., p. igi. 
 
 4. Brooman (ib. et Murexide). Dingl. Journ., t. cxliv., p. 68 ; t. cxlv., p. 137 ; 
 
 t. clvi., p. 236. 
 
 5. Schlumbebgeb and Dollfuss (Teinture avec la Murexide). Bulletin de 
 
 la Soc. Industrielle de Mulhouse, 1854, No. 120, pp. 242, 280. 
 
 6. Depouilly and Ch. Lauth {ih.). Moniteur Scientifique, 1859, p. 968. 
 
 7. E. Kopp (Murexide). Repertoire de Chim. Appliq., 1859, t. i., p. 79. 
 
 8. Clark (ib.), Dingl. Polytechn. Journ., t. cli., pp. 141, 203. 
 
 9. Th. Wuetz (Teinture). Dingl. Journ. t. cliii., p. 212. 
 
'fc^VW|fW^VSfr¥^W*. , 
 
 ^^^^^^^^^^^^^^^^^^^H 
 
(7 X 7 
 
 INDEX. 
 
 ACETATE of lime, red liquor 
 from, 289 
 Aceto-ferruginous solutions, applica- 
 tion of, 290 
 Acid, aloetic, 417 
 
 — amalic, 509 
 
 — anthrachinon bisulphuric, 224 
 
 — anthranilic, 172 
 
 — carbolic, 215 
 
 — carminic, 356 
 
 — carthamic, 142, 385 
 
 — catechutannic, 491 
 
 — chlorostannic, 530 
 
 — chloroxynaphthalic, 679 
 
 — chrysammic, 417 
 
 — chryseic, 678 
 
 — chrysinic, 426 
 
 — chrysophanic, 425 
 
 — erythric, 370 
 
 — erythrosic, 364 
 
 — from cotton, 36 
 
 — gallic, 502 
 
 — gentianic, 426 
 
 — hydrochloric, 520 
 
 — isopurpuric, 219, 674 
 
 — lizaric, 242 
 
 — morintannic, 406 
 
 — muriatic, 520 
 
 — nitric, 74, 520 
 
 — nitrococcussic, 357 
 
 — nitrocuminic, 512 
 
 — nitro-xynaphthalic of Dusart and 
 
 Gelis, 678 
 
 — normal hydrochloric, 124 
 nitric, 124 
 
 oxalic, 124 
 
 sulphuric, 122 
 
 — orsellic or orsellinic, 373 
 
 — parelline or parellic, 374 
 
 — phenic, 215 
 
 — picramic, 219 
 
 — picric, 219 
 
 — picrocyanic, 219 
 
 — pyrogallic, 503 
 
 Acid, preparation of picric, 673 
 
 Acid, purpuric, 168 
 
 — quercitannic, 396 
 
 — rosalic, 674 
 
 — rosolic, 683 
 
 — rufigallic, 687 
 
 — rutinic or rutic, 410 
 
 — stannic, 519 
 
 — sulphindigotic, 445 
 
 — sulphonaphtholic, 681 
 
 — sulphuric, 521 
 
 — tannic, 502 
 
 — tartaric, 549 
 
 — usnic, 425 
 
 — viridic, 513 
 
 — vulpic, 425 
 Acidimetry, 131 
 Ageing, 280 
 Albumen, 75 
 
 — adulteration of, 688 
 
 — blood, 639 
 
 — coagulated, 76 
 
 — egg, 80 
 
 — qualitative testing of, 78 
 
 — quantitative estimation of, 78 
 
 — substitutes, 81 
 
 — vegetable, 75 
 Albumenoid substances, 73 
 
 applying in fixing colours, 80 
 
 Alcohol, phenic, 215 
 
 — substances soluble in, 234 
 Alcohols, naphthylic, 680 
 Aldehyde, green, 205 
 Algaroth, 509 
 
 Alizarin, 143, 242, 252, 308 
 
 — artificial, 222 
 
 — green, 246, 248 • 
 
 — pure crystalline, to dye with, 
 
 247 
 
 — yellow, 246 
 Alkalies, carbonated, 125 
 
 — caustic, 129 
 
 estimation of, 128 
 
 Alkalimeter, 123 
 Alk ilimetry, 122 
 Alkanet, 384 
 
**v**«***4< 
 
 .^fc.H,..:!.,.*! »*■■.„ 'T- »** » *» *>»* 
 
 718 
 
 Alloxan, 169 
 Alloxantine, 169 
 Aloe resin, 415 
 Aloes, 415 
 
 — varieties of, 415 
 Aloetic acid, 417 
 Aloetin, 416 
 Aloin, 416 
 Alum, 275 
 
 — ammonia, 275 
 
 — neutral or cubical, 276 
 
 — potash, 275 
 Alumina, 143 
 
 — acetate of, 142, 207, 226 
 
 — fixing upon woven fabrics, 279 
 
 — hyposulphite of, as a mordant, 285 
 
 — hydrochlorate of, 276 
 
 — muriate of, 276 
 
 — nitrate of, 226, 276 
 
 — sulphate of, 276 
 Aluminate of potassa, 27 
 Amalic acid, 509 
 Ammonia, 120, 130 
 
 — carbonate of, 1*1 
 
 — haematate of, 345 
 
 — isopurpurate of, 219 
 
 — nitrate of, 121 
 Ammoniacal cochineal, 358 
 
 — salts, 120 
 Ammonium, chloride of, 121 
 
 — chlorostannite of, 526 
 Amylum, 66 
 Aniline black, with madder-red and 
 
 chrome-orange, specimen, 647 
 
 — blue, apparatus for preparation of, 
 
 198 
 
 colouring linen yarn, 61 
 
 method of manufacturing, M. 
 
 Marnas's, 196 
 
 — colours derived from, 171 
 
 detection of, 669 
 
 method of fixingupon cotton, 195 
 
 — crimson, 187 
 
 — discovery of, 171 
 
 — Hofmann's process, 173 
 
 — mordants, 185 
 
 — red, 178 
 production of, 178 
 
 — salt, solution of, 645 
 Anilines, commercial value of, 176 
 Animal fibres, 73 
 
 — origin, thickenings of, 73 
 Annatto, 426 
 
 — colouring matters of, 427 
 Anotto, 426 
 Anthokirrin, 509 
 Anthracen, 222 
 
 — colours, 222 
 
 — method of determining, 690 
 
 — orange, 681 
 
 — quantitative examination of, 695 
 
 INDEX. 
 
 Anthrapurpurin, 683 
 
 — discovery of, 327 
 Apparatus, padding, 582 
 Application colours, 635 
 Aquafortis, 521 
 
 — single, 521 
 Arabine, 70 
 Archil, see Orchil. 
 Argentine, 151 
 Argol, red, 549 
 
 — white, 549 
 Argols, 548 
 Arsenic and glycerin standard, 207 
 
 — and arsenious acid, n 
 
 — mordants, 545 
 
 — preparation of, 223 
 Artificial alizarin, printing with, 225 
 Astragalus veins, 71 
 Astringents, 490 
 
 — true, 499 
 Aurin, 6S3 
 
 Avivage, 275, 301, 352 
 Azaleine, preparation of, 179 
 Azuline, 196 
 
 "D ABLAH, 509 
 
 Babulah, 509 
 Ball soda, 114 
 Baphia nitida, 341 
 Balsamodendron, 382 
 Baraniline, 176 
 Barbatimas, 509 
 Bark, alder, 508 
 
 — barberry, 423 
 
 — butternut, 510 
 
 — mahogany tree, 512 
 
 — Panama, 652 
 
 — pomegranate root, 512 
 
 — quercitron, 394 
 
 Bahlow, Mr., bleaching under pres- 
 sure, 45 
 
 Barwood, 341 
 
 — red, 341 
 
 Baryta, sulphate of, 151 
 Bath, arsenite of soda, 157 
 
 — chalk, 325 
 Batist, Flemish, 57 
 Bauxite, 279 
 Bearberry, 509 
 Bently, David, continuous process 
 
 of bleaching, 52 
 Benzol, chloride of, 245 
 
 — discovery of, 173 
 Benzyl, chloride of, 674 
 Berberine, 423 
 Berries, Persian, 403 
 
 — privet, 512 
 Bichloride, aqueous, 530 
 Bichrome olive, 96 
 Bignonia chica, 388 
 
INDEX. 
 
 719 
 
 Bilberries, 509 
 Binitro-anthraquinon, 682 
 Bismarck, 98 
 
 — aniline, 98 
 
 — colouring linen yarn, 62 
 
 — for woollen yarn, 629 
 Bisulphate of potash, 11 r 
 Bixin, 141, 426 
 
 Black, 99, 624, 630, 635, 639, 692 
 
 — aniline, 211, 646 
 specimen, 215 
 
 — blotch, 624 
 
 — bluish application, 347 
 
 — cheap, 100 
 
 — chrome, 99 
 
 — colouring linen yarn, 62 
 
 — fast, 100 
 
 — for French merinos, 624 
 
 — for objects, 624 
 
 — for silk-striped thibets, 100 
 
 — madder and aniline, specimen, 579 
 
 — sumach, 100 
 
 — on woollen yarn, 629 
 Blacks, to test, 662 
 Bleaching, 44, 275 
 
 — continuous process of, 52 
 
 — carpet yarn, 88 
 
 — field, 312 
 
 — linen, 57 
 
 — liquor, Ramsay's, 139 
 Wilson's, 139 
 
 — powder, 139 
 
 — silk, 106 
 
 — under pressure, 45 
 
 — wool, 86 
 
 — woolle.-n yarn, 88 
 Bleu de Lyons, 196 
 
 — de Mnlhouse, 196 
 
 — de Paris, 196 
 Blue, 338, 631, 635 
 
 — aniline, 92 
 
 — chrome, 91 
 
 — colouring substances, 438 
 
 — dark, 625 
 
 indigo, 91 
 
 specimen, 164 
 
 — French, 167 
 
 — iron, 201, 463 
 
 — light, specimen, 164 
 
 — naphthoic, 679 
 
 — Nicholson's, specimen, 203 
 
 — Prussian, 91, 162 
 
 — purple, 91 
 
 — royal, 625 
 
 — Runge's, 190 
 
 — Saxony, 91 
 
 — topped logwood, go 
 
 — Turnbull's, 165 
 Blues, China, 565 
 resist for, 485, 593 
 
 — cobalt, 167 
 
 Blues, detection of, 663 
 
 — refined, 198 
 
 — soluble, 199 
 Bluish-black application, 347 
 Boiler incrustations, 14 
 Bombyx, 104 
 
 Bowking, 48 
 Branning, 309 
 Brauna-wood, 510 
 Bresiline, 335 
 
 Broadcloth, dark blue for, go 
 Bromelia ananus, 64 
 Bronzes, 566 
 
 — manganese, 638 
 Brown, 227, 626, 632, 636 
 
 — camwood, 97 
 
 — chrome, 97 
 
 — fast, 97 
 
 — light, 97 
 
 — naphtha, 208 
 
 — standard dark, specimen, 604 
 
 light, specimen, 604 
 
 Browns, aniline, 207 
 Buccinum, 171 
 
 Buff, 626 
 
 Buckwheat, colouring matter from, 412 
 
 Burls, 539 
 
 — chemical removal of from wool 
 
 and woollen goods, 694 
 
 /^ACTACE.^), 350 
 
 Caclin, 510 
 
 Cadmium, sulphide of, 154 
 
 Caesalpinia brasiliensis, 331 
 
 — crista, 331 
 
 — echinata, 331 
 
 — sappan, 332 
 
 — vesicaria, 332 
 
 Calico, Hofmann's violet on, 613 
 
 — printing aniline colours on, 689 
 Calico-printing, styles of, 563 
 
 — printing-ink for use in, 688 
 Campeachy, 342 
 Cannabis sativa, 63 
 Cane-sugar, 233 
 Caoutchouc, solution of, 639 
 Caragara, 388 
 
 Carbonaceous grey, with chrome- 
 black, chrome-green, chrome- 
 yellow, and extract of madder, 
 specimen, 643 
 
 Carbonate of ammonia, 121 
 
 — of lime, 150 
 
 — of soda, 113 
 Carbonated alkalies, 125 
 Carminaphtha, 679 
 Carminates, chemical history of, 357 
 Carmine, 359 
 
 — adulteration of, 359 
 
 — prescriptions for preparation of, 359 
 

 
 
 720 
 
 INDEX. 
 
 Carmine-lake, 360 
 
 
 Chromule, 435 
 
 Carminic acid, 356 
 
 
 Chrysammic acid, 417 
 
 Carpet yarn, bleaching, 88 
 
 
 Chrysammid, 687 
 
 Carpets, colouring linen yarn 
 
 or, on 
 
 Chrysaniline, 209 
 
 the small scale, 58 
 
 
 Chrysinic acid, 426 
 
 Carotin, 424 
 
 
 Chrysophanic acid, 425 
 
 Canot roots, yellow colouring 
 
 natter 
 
 Chrysoretin, 510 
 
 of, 424 
 
 
 Chrvsotoluidine, 183, 210 
 
 Carthamin, 385, 386 
 
 
 Cinnabar, 152 
 
 Carthamus tinctorius, 384 
 
 
 Citrates, 234 
 
 Casein, 78, 185 
 
 
 Cloth, dunging of, for garancin work, 
 
 Cashew, 490 
 
 
 299 
 
 Catechu, 490, 493 
 
 
 Coal-tar, 173 
 
 Catechuin, 492 
 
 
 Coccus, 350 
 
 Catechutannic acid, 491 
 
 
 — Cadi, 1 
 
 Caustic alkalies, 129 
 
 
 Coccedia viridis, 510 
 
 Cellulose, 17, 19 
 
 
 Cochineal, 1, 350, 6og 
 
 Cerise, 675 
 
 
 — ammoniacal, 358 
 
 Chalk, 150 
 
 
 — cultivation of, 352 
 
 — French, 151 
 
 
 — employment of in dyeing and 
 
 Charbon sulphurique, 247, 257 
 
 
 printing, 361 
 
 Chayaver, 328 
 
 
 — Honduras, 352 
 
 Chemical agents, bleaching 
 
 with 
 
 — Java, 353 
 
 other, 56 
 
 
 — oak, 353 
 
 Chemick, 49 
 
 
 — paste, 88 
 
 Chestnut, 510 
 
 
 — selection of, 361 
 
 Chica, 388 
 
 
 — shades obtainable upon wool by 
 
 Chicory, 5ro 
 
 
 means of, 363 
 
 Chinese yellow dyes, 421 
 
 
 — Vera Cruz, 352 
 
 Chlorate of potash, 113 
 
 
 Cocoa-nut tree, 510 
 
 Chloride of ammonium, 121 
 
 
 Coir, 64 
 
 — of benzol, 245 
 
 
 Cold water, substances soluble in, 233 
 
 — ferric, 536 
 
 
 Colour bath, 247 
 
 — ferrous, 536 
 
 
 — cochineal, detection of, 670 
 
 — of lime, 120, 138 
 
 
 — stone, 99 
 
 — of manganese settlers, 133 
 
 
 — wood, 380 
 
 — of sodium, 119 
 
 
 Colours, aniline, Dale's process for 
 
 — stannic, 530 
 
 
 printing and dyeing with, 692 
 
 Ohlorides, 132 
 
 
 — anthracen, 222 
 
 Chlorimetry, 132 
 
 
 — application, 635 
 
 Chlorine, 132 
 
 
 — behaviour of, on different fibres. 
 
 — in chlorine water, estimation of, 140 
 
 with reagents, 669 
 
 — introduction of, of Messrs. 
 
 3lech, 
 
 — cyanogen, 162 
 
 Steinbach, and Mantz, 3 
 
 11 
 
 — fixing of, 80, 144 
 
 — method,. Weldon's, 132 
 
 
 — from uric acid, 168 
 
 — preparing, 132 
 
 
 — garancin, 564, 579 
 
 — water, 132 
 
 
 — influence of light upon, 655 
 
 Chloring, 310 
 
 
 — madder, 564 
 
 Chlorogenin, 234 
 
 
 detection of, 671 
 
 Chlorophyl, 435 
 
 
 — naphthalin, 220 
 
 Chocolate, 626, 632, 636 
 
 
 — on woollens, 89 
 
 Chromate colours, use of, W 
 
 . Las- 
 
 — on wools and warps, 100 
 
 sainger, 154 
 
 
 — pigment, 566 
 
 — of potash, in 
 
 
 — soluble in water, 252 
 
 Chrome alum, 544 
 
 
 — spirit, 565, 635 
 
 — or canary yellow, specimen 
 
 155 
 
 — steam, 565, 598 
 
 — green, 156 
 
 
 — upon calico, red and rose-reds used 
 
 specimen, 157 
 
 
 for, 338 
 
 — orange, light and dark, specimen, 
 
 — yellow vegetable, 393 
 
 645 
 
 
 Colouring matters, 252 
 
 Chromium, metaphosphate of, 
 
 158 
 
 brown and black, 490 
 
INDEX. 
 
 721 
 
 Colouring matters, green, 428 
 
 in cotton, 37, 39 
 
 new class of, 690 
 
 of doubtful existence, 252 
 
 of organic origin, 168 
 
 of various origin, 388 
 
 valuation of quantity in mad- 
 der, 272 
 
 yellow, of Chinese origin, 421 
 
 Cook, J ames, singeing cotton fabric, 44 
 Copper, acetate of, 545 
 
 — aceto-arsenite of, 156 
 
 — ammoniuret of, 546 
 
 — arsenite of, 156 
 
 — chloride of, 547 
 
 — muriate of, 547 
 
 — nitrate of, 547 
 
 — sulphate of, 547 
 Copperas, 535 
 Corallin, 696 
 
 — orange-red, 633 
 
 — preparation of, 2x7 
 
 — yellow, 683 
 Corchorus olitorius, 63 
 Cork, 518 
 
 Cotton, 21 
 
 — acid from, 36 
 
 — bleaching raw, in small quanti ties, 52 
 
 — cochineal-red on, 6Sg 
 
 — colouring matters in, 37, 39 
 
 — fibre, 21 
 
 constituents of, 29 
 
 — steam black on, 347 
 
 — stockings, bleaching, 50 
 
 — warps, dark spirit violet on, 6g2 
 aniline blue, magenta, purple, 
 
 Saxon blue, scarlet on, 101 
 
 — wax, 30, 34 
 
 — yarn, dyeing aniline blacks on, 688 
 Cow-dung, 294 
 
 — influence of in cleansing, 296 
 Crabbing, 654 
 
 Crajura, 388 
 
 Creeper, Virginia, 513 
 
 Crimson, colouring linen yarn, 60 
 
 — with cochineal, 93 
 Crocin, 423 
 
 Crum, Walter, cotton, 28 
 Cuba wood, 365 
 Cudbear, 368 
 
 — adulteration of, 378 
 
 — manufacture of, 377 
 Curcumin, 418 
 
 — researches on, by M. F. W. Daube, 
 
 420 
 Cutch, 490 
 
 — brown (fast), colouringlinen yarn, 62 
 
 — fixing by means of bichromate 
 
 (MM. Koschlin Freres), 496 
 
 — yellow, 491 
 Cyanin, 390, 685 
 
 Cyanogen colours, 162 
 
 •pvALLEIOCHIN, 686 
 
 Dahlia, 94 
 Decomposed vat, 90 
 Delaine, preparing, 615 
 Delaines, method of printing, 613 
 Dextrine, 68 
 Discharge, 317 
 
 — style, 594 
 
 — white, 692 
 Diphenylamine, 675 
 Divi-divi, 500 
 Drab, 98 
 
 Dung, substitutes for, 297 
 
 Dung-bath, 297 
 
 Dye-beck, 299 
 
 Dye-lac, 355 
 
 Dye materials, 142 
 
 Dyewoods, preparation of extracts of, 
 
 513 
 Dyes, Chinese yellow, 421 
 
 — detection of on yarn or pieces, 662 
 Dyeing, green, 432 
 
 — operations accessory to, 651 
 
 — Turkey-red, 321 
 
 — use of Epsom Salts in, 689 
 
 "Cp AUX de Javelle, 139,314 
 
 Eaux de Labarraque, 139 
 
 Ebony green, 511 
 
 Effects, indigo, 585 
 
 Egg albumen, 80 
 
 Enlevage, 317 
 
 Epidermic products, 82 
 
 Erythric acid, 370 
 
 Erythrite synonyms, 371 
 
 Erythrine, 370 
 
 Erythrodanon, 228 
 
 Erythrose, 364 
 
 Erythrozym, 239 
 
 Extract of madder red and pink with 
 chrome orange, green, ultra- 
 marine blue, and chrome black 
 (specimen), 644 
 
 ■pECULA, 68 
 
 Feuille Morte, 380 
 Fibre, cocoa-nut, 64 
 
 — linen, 57 
 
 — vegetable, 17, 183 
 Fibres, animal, 73 
 
 — cotton, 21 
 
 — mineral, 16 
 
 — vegetable, distinguishing from each 
 
 other, 65 
 
 — woollen, 83 
 Fibrine, 78 
 
 3*- 
 
722 
 
 INDEX. 
 
 Fibroine, 105 
 Finishing, 655 
 Firing, 529 
 Flax, 27, 57 
 
 — New Zealand, or Phormium tenax, 
 
 64, 107 
 
 to distinguish from ordinary 
 
 flax or hemp, 65 
 
 — ordinary, to distinguish from New 
 
 Zealand flax, 65 
 Fleur de garance, 253, 271 
 Flowers, colouring matters of, 389, 424 
 Fustet, 411 
 Fustic, 405, 349 
 
 — carmine, 365 
 
 — colouring matters of, 405 
 
 — detection of, 672 
 
 — old, 405 
 
 — varieties of, 405 
 
 — young, 411 
 
 — Zante, 411 
 Fustin, 411 
 
 /"* ALLS, Aleppo or Turkey, 499 
 
 — chief commercial varieties, 499 
 
 — French, 499 
 
 — Istria, 499 
 
 — Morea, 499 
 
 — Piedmontese, 499 
 
 — so-called Marmorine, 499 
 
 — Smyrna, 499 
 Gallein, 568,684 
 Gambier, 490 
 Garance, 228 
 Garancage, 275, 300 
 Garanceux, 253, 261 
 Garancin, 257 
 
 — dunging of cloth for, 299 
 
 — specimen, 579 
 
 — substitute for, 262 
 
 — red mordant for, 284 
 
 — style, 308 
 Garnet, soluble, 219 
 Gelatin, solution of, 502 
 Gentianic acid, 426 
 Geranosine, 206 
 Glucose, 233 
 Glucosides, 240, 252 
 Gluten, 78 
 
 Goods, woollen, printing, 624 
 Gossypium arboreum, 21 
 Grain, Polish, 356 
 Grass, Chinese, 63 
 Green, 627, 633, 636, 638 
 
 — aniline, 96, 202 
 with picric acid, 96 
 
 — Arnaudon, 158 
 
 — Barasat, 435 
 
 — Chinese, 428 
 
 — chrome, 95 
 
 Green, colouring linen yarn, 59 
 
 — crystalline, 205 
 
 — dyes, of vegetable origin, 434 
 
 — for broadcloth, 95 
 
 — for yarn, 95 
 
 — iodine, 202 
 
 manufacture of, 202 
 
 — logwood, 95 
 
 — methylaniline, 678 
 
 — olive, 96 
 
 — padded ground, with design in 
 
 madder, red and pink, chrome- 
 orange, green and black, speci- 
 men, 645 
 
 — Paris, 678 
 
 — Plessy, 158 
 
 — quinine, 686 
 
 — Scheele's, 156 
 
 — Schweinfurt, 156 
 
 — soluble, preparation of, 204 
 
 — Wilner, an arsenical, specimen, 157 
 Greens, detection of, 666 
 
 — dipped, 594 
 
 — indigo, 594 
 Grey, 628, 633 
 
 — aniline (Castelhaz), specimen, 
 
 680 
 
 — silver, 99 
 Greys, aniline. 210 
 Guano, Peruvian, 169 
 Guignet's green and chrome-green, 
 
 chrome-black and dichromate of 
 
 lead, specimen, 641 
 Guilandina, 329 
 Gum, 69, 233 
 
 — Arabic, 70 
 
 — kino, 491 
 
 — lac, 353 
 
 — Senegal, 70, 286 
 
 — tragacanth, 71 
 
 — yellow, 673 
 
 Gums, soluble in water, belonging to 
 
 the species of Arabic gums, 69 
 Gypsum, 150 
 
 TJACHROUT, 330 
 
 Hasmatin, 345 
 
 Hematoxylin, 343 
 
 Hasmatoxylon campechianum, 342 
 
 Harmala red, 364 
 
 Heath, 511 
 
 Hellebore, 511 
 
 Hemlock, 511 
 
 Hemp, 63 
 
 — Bombay, 64 
 
 — Manilla, 64 
 
 — Ramee, 63 
 
 — Rhea, 63 
 
 Hibiscus cannabinus, 64 
 Hiccory, 511 
 
INDEX. 
 
 723 
 
 Hoang-p^-pi, 421 
 
 Hoang-tchi, 422 
 
 Hohang-teng, 421 
 
 Holly, 511 
 
 Hollyhock, 511 
 
 Homorceine, 219 
 
 11 >rse-chestnut, 511 
 
 Horse-radish, 511 
 
 Hosier)', indigo-blue on wool, go 
 
 Hydroquinon, derivatives of, 684 
 
 Hydroxide of sodium, 129 
 
 Hypernic, 60 
 
 Hypochlorite of lime, 120 
 
 — of potash, 113 
 
 — of soda, 119 
 
 Hypochlorites, estimation of, 141 
 Hyposulphite of soda, rig 
 
 T NDIAN yellow, 425 
 
 Indigo, 89 
 
 — adulteration of, 462 
 
 — blue, composition of materials 
 
 used for discharging, 475 
 part logwood, gi 
 
 — blues, 565 
 
 — bottom, mode with, 98 
 
 — Brazil, 457 
 
 — Caraccas, 456 
 
 — carmine, 463 
 
 — Carolina, 457 
 
 — detection of, 672 
 
 — green, 435 
 
 — Guatemala, 456 
 
 — impurities found in, 462 
 
 — industri ally-prepared sulphuric 
 
 acid d erivatives of, 463 
 
 — Madras, 456 
 
 — Manilla, 456 
 
 — manufacture of in Bengal, 447 
 
 — Mexican, 456 
 
 — mode without, 98 
 
 — printing with, 475 
 
 — receipts for dissolving, 463 
 
 — reduction of, 469 
 
 — refined, 466 
 
 — sulphuric derivatives of, applica- 
 
 tion of, 487 
 
 preparations of, used in dyeing 
 
 and printing, 465 
 
 — trade terms generally applied to, 457 
 
 — vats, theory of, 469 
 
 — white, 441 
 
 Indigos, Oude and Coromandel, 455 
 
 — Senegal and Mauritius, 457 
 Indigotin, 142, 438, 443 
 
 — amorphous, 439 
 
 — fixing, by reduction method, 468 
 
 — methods for quantitative estima- 
 
 tion of, 458 
 of fixing in printing, 482 
 
 Indigotin, sublimed, 439 
 
 — to bleach, 458 
 Indin, 447 
 Indirubin, 454 
 
 Insoluble colours, mechanical fixation 
 
 of, 147 
 Introduction, 1 
 Iodine, 140 
 
 — green, 202 
 
 — solution of, 523 
 Iron, acetate of, 536 
 
 — black, 538 
 
 — blue, 538 
 
 — buff, 154 
 
 specimen, 155 
 
 — common, for drabs, 539 
 
 — hyposulphite of, 292 
 
 — in water, II, 12 
 
 — liquor, 291 
 
 — muriate of, 536 
 
 — nitrate of, 61, 536 
 
 — permuriate of, 536 
 
 — persulphate of, 536 
 
 — protosulphate of, 535 
 
 — red sulphate of, 536 
 
 — - solution of protocliloride of, 536 
 
 — to fix peroxide of, 290 
 Irons, burling, 539 
 
 — saddening, 539 
 
 — to test, 540 
 Isatin, 446 
 
 Isatis indigotica, 454 
 
 — tinctoria, 452 
 Isopurpuric acid, 219, 674 
 Isopurpurin, artificial, 682 
 
 J 
 
 ASPEADA, 351 
 
 Jaune d'Or, 222 
 job dyeing, 653 
 Jute, 63 
 
 T^ERMES, animal or vegetable, 352 
 
 Khail cedra, 511 
 Kiers, bleaching, 45 
 Kino, 491 
 Krapp, 228 
 Knoppern, 499 
 Kuphaniline, 176 
 Kyanol, 17; 
 
 f AC dye, 355 
 
 colouring matter of, 355 
 
 - • lake, 355 
 
 Lactarine, 79, 185 
 
 Lake colours, preparation of, 365 
 
 — green, 366 
 Lakes, 337 
 
 — aniline, 367 
 

 i«fe•wfe«ss | ^^'^i' , * ^ttiitiMt^^tf^^^tf^p^ 1 ^ 
 
 •^^ja£#^J*o*«te *.***■# ;-!»W(i 
 
 
 724 INDEX. 
 
 Lakes, blue, 366 
 
 Lizaric acid, 242 
 
 — cochineal, 366 
 
 Logwood, 342 
 
 — yellow and orange, 367 
 
 — blue, 346 
 
 Lamium album, 511 
 
 — decoctions, 348 
 
 — purpureum, 511 
 
 — extract of, 347 
 
 Lan, 489 
 
 Lokao, 428 
 
 Lapatliin, 426 
 
 — French process for dyeing with 
 
 Lapis lazuli, 80, 158 
 
 433 
 
 Lavender, 99 
 
 - - purification of, 430 
 
 Lawsonia inermis, 511 
 
 Lutein, 393 
 
 Lazulite, white, 589 
 
 Luteolin, 407 
 
 Lead, acetate of, 541 
 
 Lye, crude soda, 116 
 
 — alkaline solutions of, 541 
 
 
 — nitrate of, 541 
 
 A/TACHINE, cylinder, 551 
 
 — subacetate of, 541 
 
 — sugar of, 541 
 
 — perrotine, 551 
 
 — sulphate of, 541 
 
 — printing, routine of, 560 
 
 Leaves and green parts of plants, 
 
 — straining (Dollfus and Mieg), 562: 
 
 colouring matters of, 435 
 
 Maclurin, 407 
 
 Leblanc's process, 117 
 
 Madder, 228. 2go 
 
 Legumine, 79 
 
 — adulteration of, 232, 273 
 
 Leguminosae, 337, 342 
 
 — application of colouring principles 
 
 Libavius, fuming spirit of, 530 
 
 contained in, 315 
 
 Libi-divi, 500 
 
 — art of dyeing with, 300 
 
 Lichens, chemical history of colouring 
 
 — commercial products or derivatives 
 
 matters of, 369 
 
 from, 252 
 
 — colouring matters derived from, 367 
 
 — composition of, 233 
 
 — discovery of colour-yielding pro- 
 
 — concentration of, 257 
 
 perties of, 367 
 
 — conspectus of colours of, 252 
 
 — yellow colouring matters of, 425 
 
 — cultivation of, 230 
 
 Light, action of as a destroyer of 
 
 — dyeing with, 299 
 
 colours, 657 
 
 — lake, 365 
 
 — experiments on action of, 659 
 
 — lakes, preparation of, 269 
 
 Lilac, 628 
 
 of deepest shade, 366 
 
 — colouring linen yarn, 61 
 
 — orange, 252 
 
 — standard, 603 
 
 — ordinary, style work, 307 
 
 Lilacs, steam, 608 
 
 — preparations for dyeing purposes, 
 
 Lime, acetate of, 227 
 
 273 
 
 — action of, for fixing purples, 320 
 
 — preparing bloom of, 254 
 
 — carbonate of, 150 
 
 — printing, 315 
 
 — chloride of, 49, 120, 138, 311 
 
 — process of purifying, 263 
 
 — hypochlorite of, 120 
 
 — reaction of colouring principles of, 
 
 — in water, 11 
 
 243 
 
 — salts, 120 
 
 — red ground, black and white on, 691 
 
 — sulphate of, 150 
 
 mordant for, 287 
 
 Linen, bleaching, 57 
 
 — rose, 248 
 
 — fibre, 57 
 
 — salmon with, 94 
 
 — yarn for carpets, colouring, 58 
 
 — Schlumberger's process for esti- 
 
 white bleaching, 58 
 
 mating utilisable tinctorial value 
 
 Linum usitatissimum, 57 
 
 of, 269 
 
 Liquor, black, 536, 649 
 
 — style, catechu mixture for, 497 
 
 — iron, 291 
 
 — styles, clearing, 313 
 
 — potassa, 314 
 
 — substitutes for, 329 
 
 — red, 288 
 
 — tinctorial matters of, 253 
 
 Liquors, red, prescriptions for, M. D. 
 
 — use and application of, 273 
 
 Kcechlin, 283 
 
 — varieties of, 236 
 
 Lithospermum arvense, 511 
 
 — Zealand, 257 
 
 Litmus, 383 
 
 Madders, testing of, 269 
 
 — chief use of, 380 
 
 Magenta, 93, 178, 184 
 
 Livi-divi, 500 
 
 — colouring linen yarn, 61 
 
 Lixiviation, Shanks's process, 115 
 
 ■ — printing, 185 
 
INDEX. 
 
 7 2 5 
 
 Magenta, specimen, 186 
 Magentas, examination of, 185 
 
 — testing, 185 
 Magnesia in water, 11 
 Mahaleb, 512 
 Malates, 234 
 
 Malvaceae, colouring matters of, 390 
 
 Manchester yellow, 222 
 
 Manganate of potash, 112 
 
 Manganese settlt-rs, chloride of, 133 
 
 Mangrove, 512 
 
 Manilla, 107 
 
 Maroon, 94, 626 
 
 Marina, 232 
 
 Matters, amylaceous, 66 
 
 Mauvaniline, 182 
 
 Mauveine, 187 
 
 Measures of capacity, 700 
 
 Meekrapp, 228 
 
 Melin, 410 
 
 Mercerising, 281 
 
 Mercury, biniodide of, 152 
 
 — sulphide of, 152 
 
 Merino shade, bleaching cotton stock- 
 ings, 51 
 
 — wool, 84 
 
 Methyl diphenylamine, 675 
 Mineral fibres, 16 
 
 — pigments, 148 
 
 — thickenings, 17 
 Mordant, black, 536 
 
 — for purples, 291 
 
 — Hellot's, 528 
 
 — new iron, 689 
 Mordants, 145, 275 
 
 — alkaline iron, 541 
 
 — alumina, 534 
 
 — aniline, 185 
 
 — antimony, 542 
 
 — arsenic, 545 
 
 — binary, 305 
 
 — bismuth, 543 
 
 — chromium, 544 
 
 — copper, 545 
 
 — fixing of, by ageing, 280 
 
 — for brown, 292 
 
 — iron, 535 
 
 — lead, 541 
 
 — manganese, 545 
 
 — methods of thickening, 286 
 
 — prescriptions of thickened, 287 
 
 — printing and fixing, 275 
 
 — tin, 519 
 
 — tungsten, 542 
 
 — zinc, 545 
 Morin, 407 
 
 Morinda citrifolia, root of, 391 
 Morindin, 391 
 Morintannic acid, 406 
 Mosaics, red for, 225 
 Mucilage, 233 
 
 Mucilage, various, 71 
 Mulberry tree, 104 
 Mummy-cloth, 21 
 Mungeet, 329 
 Murex brandaris, 171 
 Murexide, 168, 170, 219 
 
 — discovery of, 168 
 Muriate of tin, 59, 523 
 Musa textilis, 64 
 Muslins, bleaching, 50 
 Myrobalans, 500 
 
 -VTAPHTHOLS, 680 
 
 Naphtha, brown, 208 
 Naphthalin colours, 220 
 
 — yellow, detection of, 672 
 Naphthylamin violet, 221 
 Neb-neb, 509 
 
 Negra, 351 
 
 Nitrate of ammonia, 121 
 
 — of iron, 61 
 
 — of potash, in 
 
 — of tin, 60, 527 
 Nitro-benzol, 173 
 
 — detection of, 175 
 Nitro-coccussic acid, 357 
 Nitro-cuminic acid, 512 
 Nona, 329 
 
 Normal sulphuric acid, 122 
 Nucin, 512 
 Nuts, areca, 509 
 
 — Valonia, 500 
 Nut-galls, China, 500 
 Nymphaea alba, 512 
 
 CE 
 
 NOLIN, 392 
 
 Oil employed in Turkey-red dyeing, 146 
 
 — Gallipoli, 321 
 Olive, bichrome, g6 
 
 — cheap, 96 
 
 — zephyr, 97 
 
 Orange, 94, 633, 628, 636 
 
 — aniline, 209, 210 
 
 — with annatto, colouring linen yarn, 
 
 60 
 
 — anthracen, 681 
 
 — aurin, 217 
 
 — Blackley, 692 
 
 — with madder, colouring linen yarn, 
 
 60 
 Orcein, 375 
 Orchil, applications of in dyeing and 
 
 printing, 379 
 
 — artificial, 694 
 
 — colouring matters of, 374 
 
 — liquor, to prepare, 377 
 
 — new methods of preparing, 375 
 
 — paste, ordinary method of pre- 
 
 paring, 376 
 
726 
 
 IXDEX. 
 
 Orcin, preparation of, 374 
 
 — pure, 373 
 
 Organic matter in water, 13 
 Orpiment, 154 
 Ouongkondou, 330 
 Oxalate of potash, in 
 Oxide, chromic, 544 
 
 — hydrochlorate of stannic, 530 
 Oxidiser, 133 
 
 Ozone, 74, 132 
 
 P 
 
 ADDING, 581 
 
 Para-carthamin, 512 
 Parelline or pareliic acid, 374 
 Paste, cochineal, 88 
 
 — violet, test of, 191 
 Pastel, 453 
 
 Peachwood liquor, 60 
 Pe&ic acid, 40 
 Pectose, 234 
 
 Pensee brown, colouring linen yarn, 61 
 
 Peonine, 196 
 
 Perchloride, solution 0^536 
 
 Pericarpium, 64 
 
 Permanganate of potash, 112 
 
 — of soda, 119 
 Perrotine, working of, 554 
 Persian berries, 403 
 
 detection of, 672 
 
 Phalaena mori, 104 
 Phenicienne, 207, 220, 674 
 Phenol, 215 
 
 — coloured derivatives of, 215 
 Phenyl, hydrate of, 215 
 Phenylation, 194, 197 
 Phormium tenax, 64, 107 
 Phosphate of soda, 119 
 Phosphine, 209 
 Phycocyan, 512 
 Phycoerythrin, 512 
 Phycohcematin, 512 
 Phyllocymin, 435 
 Phylloxanthin, 435 
 Phytomelin, 410 
 
 Picramic acid, 219 
 
 Picric acid, aniline green with, 96 
 
 preparation of, 673 
 
 Picro-erythrine, 371 
 Pigment printing, 639 
 Pigments, blue and violet, 158 
 
 — green mineral, 156 
 
 — mineral, 148 
 
 — principal vehicles used for, 639 
 
 — red mineral, 152 
 
 — yellow mineral, 154 
 Pincoffin, 262 
 Pine-apple plant, 64 
 
 Pink, 225, 628, 633, 637, 638 
 
 — cochineal, specimen, 609 
 
 — for listings, 93 
 
 Pink saffranine, specimen, 203 
 Pinks, for blocking madder work, 637 
 
 — plate, 575 
 Pistacia lentiscus, 500 
 Pittacal, 512 
 
 Plants, indigotin-producing, 448 
 
 Plaster of Paris, 150 
 
 Polish grain, 356 
 
 Polygonum tindorium, 512, 454 
 
 Ponceau, 93, 187 
 
 — specimen, 186 
 
 — for woollen yarn, 629 
 Potash, no, 126 
 
 — aluminate of, 278, 534 
 
 — bisulphate of, 11 1 
 
 — carbonate of, 127 
 
 — caustic, 128 
 
 — chlorate cf, 113 
 
 — chromate of, in, 142 
 
 — crude, 127 
 
 — hypochlorite of, 113, 139 
 
 — manganate of, 112 
 
 — nitrate of, rn 
 
 — oxalate of, 11 1 
 
 — permanganate of, 112 
 
 — sulphindigotate, 445 
 
 — \\ ater-glass, 112 
 
 — in water, 11 
 
 — vat, go 
 
 Pourpre Francaise, 378 
 Printing, 551 
 
 — ink, use of in calico printing, 688 
 
 — pigment, 639 
 
 Processes, discharge and resist, 317 
 Produces, epidermic, 82 
 Prussian blue, colouring linen yarn, 61 
 Pseudopurpurin, 2^9,252 
 Pterocarpus santalinus, 339 
 Purple, 225, 633, 637 
 
 — aniline, 99 
 
 colouring linen yarn, 61 
 
 — Byzantiun. , 171 
 
 — heart, 512 
 
 — of the ancients, 171 
 
 — regina, 191 
 
 — Spiller's, 677 
 specimen, 677 
 
 — thickening for, 226 
 
 — Tyrian, 2, 171 
 Purples, murexide, 650 
 Purpurin, 242, 247, 252 
 
 — characters of, 249 
 
 — preparing, 248 
 
 — Dr. Schunck's researches on, 251 
 
 — to prepare a steam colour with, 309 
 Purpura, 171 
 
 Purpurates, 168 
 Purpuric acid, 168 
 Purpuroxanthin, 250, 252 
 Purrhee, 425 
 Purpura hemastoma, 171 
 
I' 
 
 INDEX. 
 
 727 
 
 Pyrocatechin, derivatives of, 684 
 .UERCETIN, 399 
 
 Q 
 
 Quercitron, 395 
 
 — colouring matters contained in, 396 
 
 — decoction of, 395 
 
 — extract, detection of, 677 
 
 — use made of, 401 
 
 R 
 
 AG dyeing, 653 
 
 Random, magenta, 103 
 
 — orange, 102 
 
 — purple, 103 
 
 — Prussian blue, 103 
 
 — Saxon blue, 102 
 
 — scarlet, 102 
 
 Randoms or clouded yarns, 102 
 Red, 225, 633, 638 
 
 — amaranth, 380 
 
 — brown, chrome, 97 
 
 — colouring linen yarn, 5g 
 matters, 350 
 
 — harmala, 364 
 
 — Hofmann's xylidin, 675 
 
 — lakes, 365 
 
 — liquor, 277, 288 
 
 — madder, 93 
 
 — naphthylamine, 206 
 
 — new aniline, 68g 
 
 — picric, 219 
 
 — and pink, madder, specimen, 576 
 
 — pink, mordants for, 275 
 
 — prussiate, 163 
 
 — Turkey, with discharges, 565 
 
 — without oil, 225 
 
 — woods, chemical history of, 333 
 Reds, aniline, 178 
 
 — Coupier's aniline, 675 
 
 — detection of, 665 
 
 — thickening for, 226 
 Redoul, 501 
 Renegrida, 351 
 Resorcin, derivatives of, 684 
 
 — nitrous derivatives of, 685 
 Reserve, 318 
 
 Reserves, 319, 580, 585 
 
 — means of obtaining, 318 
 Resin, lac, 353 
 
 Resist, 318, 571 
 
 Rhamnoxanthin, 411 
 
 Rhea tenacissima, 63 
 
 Robbia, 228 
 
 Robium, 410 
 
 Roccellinine, 374 
 
 Rocon, 426 
 
 Rod, golden, 511 
 
 Roller printing, steam black for, 347 
 
 Root, Carapa, 510 
 
 — yellow Canadian, 510 
 Rosanaphthylamine, 206 
 
 Rosaniline, acetate of, 183 
 
 — hydrochlorate of, 181 
 — ■ preparation of, 179 
 
 Rose colour, mordants for, 275 
 
 — pink, 93 
 
 mordants for, 288 
 
 Roseine, 178 
 Rosolic acid, 674, 683 
 Rothine, 220 
 Rubia, 228 
 
 — cordifolia, 229 
 
 — mungista, 329 
 
 — peregrina, 229 
 — ■ tinctorium, 228 
 Rubiaceae, products of, 328 
 Rubiacin, 251 
 
 Rubian, 238 
 
 — (Schunck), 252 
 Ruberythric acid (Rochleder), 252 
 Rutin, 410 
 
 Rutinic or rutic acid, 410 
 Rufigallic acid, 687 
 
 OAFFLOWER, 384 
 
 — estimation of goodness of, 386 
 
 — varieties of, 385 
 Saffranin, test for, 689 
 Saffranin, 207 
 Saffron, 422 
 Sal-ammoniac,i2i 
 Salmon, g4 
 
 — with madder, 94 
 Santalin, 340 
 Salt, preparing, 532 
 
 — pink, 532 
 
 Salts, ammoniacal, 120 
 Saw-wort, 513 
 Scales, thermometer, 699 
 Scarlet, 92, 635 
 
 — cochineal, 92 
 
 — for delaines, 623 
 
 — grain, 353 
 
 — lac-dye, 92 
 
 — Ulrich's, 676 
 
 — for woollen yarn, 630 
 Schunck, Dr., constituents of cotton 
 
 fibre, 29 
 Shades, covering, 581 
 
 — heavy, prepare for, 600 
 Shellac, 354 
 Shumach, 501 
 
 Silica, no 
 
 — ultramarine, 161 
 Silicate of soda, 118 
 Silk, 104 
 
 — bleaching, 106 
 
 — constitution of, 104 
 
 — black, detection of, 672 
 
 — and other fibres, means of dis- 
 
 tinguishing, 107 
 Silks, method of dyeing, 630 
 
J*»**-* m. ■. ..<* »— »* » •« f*? 
 
 728 
 
 INDEX. 
 
 Terra Japonica, 490 
 Silkworm, 104 
 Singeing, 654 
 Sizal, 107 
 Slate, 99 
 
 — colouring linen yarn, 62 
 
 — purple, 99 
 
 Slates and modes on white warps, 100 
 Soap, 312 
 
 — baths, 312 
 Soaping, 309 
 
 Soda, alummate of, 279, 534 
 
 — ash, 113, 127 
 
 — Barilla, 113 
 
 — carbonate of, 113 
 
 — carminate of, 357 
 
 — caustic, 129 
 
 — hypochlorite of, 119, 139 
 
 — hyposulphite of, 119 
 
 — permanganate of, 119 
 
 — phosphate of, 119 
 
 — plumbate of, 541 
 
 — salts, 113 
 
 — silicate of, 118 
 
 — stannate of, 532 
 
 — stannite of, 526, 681 
 
 — sulphate of, 113 
 
 — tungstate of, 119, 542 
 
 — ultramarine, 161 
 
 — valuation of, 118 
 
 — vat, 90 
 
 — waste, 115 
 
 utilisation of, 117 
 
 — in water, 11 
 
 — water-glass, 118 
 Sodium, chloride of, 119 
 
 — hydroxide of, 129 
 Solution, litmus, 122 
 Solutions, test, 122 
 Sooranjee, 391 
 
 Sorgho, colouring matters contained 
 
 in, 389 
 Souring, 48 
 Spirit, amaranth, 524 
 
 — aniline, 528 
 
 — barwood, 531 
 
 — claret, 526 
 
 — another finishing scarlet, 525 
 
 — methylated, 200 
 
 — plum. 531 
 
 — purple cotton, 532 
 
 plum, or puce, 525 
 
 for wool, 528 
 
 — scarlet finishing, 525 
 
 — another yellow, 525 
 
 — yellow and orange, 525 
 Spirits, bowl, 527 
 
 — crimson, 530 
 
 — protartar, 549 
 
 — red cotton, 530 
 
 — royal blue, 550 
 
 — of salts, 520 
 
 Spirits, scarlet, 521, 527 
 Substances, albumenoid, 73 
 
 — soluble in boiling water, 234 
 Substitutes for albumen, 81 
 Stannic oxide, 519 
 
 Starch, 66 
 Steam chest, 599 
 
 style, 598 
 
 Stick-lac, 353 
 
 — varieties of, 354 
 
 Stockings, bleaching cotton, with 
 Turkey-red tops, 52 
 
 — cotton, merino shade bleachings,5i 
 Stone, blue, 547 
 
 — colour, 99 
 steam, 611 
 
 Style, indigo, first stage, specimen, 590 
 
 second stage, specimen, 591 
 
 with other colours, specimen, 
 
 59i. 
 
 — lazulitc, 587 
 
 — madder, first stage, specimen, 577 
 after dyeing, specimen, 577 
 
 after clearing, specimen, 578 
 
 — neutral, 587 
 
 — plate, 575 
 
 — produced by Lightfoot's patent 
 
 process, specimen, 592 
 
 — reserved, 564, 580 
 
 — (sixth), China blues, 593 
 
 — (eighth), 598 
 Styles, madder, 567 
 
 — padding, 565 
 
 — pigment and other, 641 
 Sulphate of baryta, 151 
 
 — ferric, 536 
 
 — ferrous, 535 
 
 — of lime, 150 
 
 — of soda, 113 
 Sulphindigotic acid, 445 
 Sulphur, recovery of, 117 
 Sulphurique, charbon, 247 
 Suint, 85 
 
 Sumac, 501 
 
 — chief varieties of, 501 
 Sumach, 501 
 Sunflower seeds, 513 
 Superargol, 550 
 
 " Syria," 513 
 
 npABLES, hydrometer, 696 
 
 Tannin, 189, 502 
 
 — estimation of in nut-galls, 503 
 Tartar, 112, 548 
 
 — cake, 550 
 
 — emetic, solution of, 502 
 
 — essence of, 549 
 
 — liquid, preparation of, 549 
 
 — substitutes for, 549 
 Tartrates, alkaline, 234 
 Terminalia Chebula, 500 
 
INDEX. 
 
 729 
 
 Terra Japonica, 490 
 
 Thibets, silk-striped, black for, 100 
 
 Thickeners, 563 
 
 Thickenings, mineral, 17 
 
 — vegetable, 17 
 
 Thom, Mr., singeing cotton fabric, 44 
 Thuya occidentalis, colouring matter 
 
 of, 411 
 Tin, bichloride of, 530 
 
 — binoxide of, 519 
 
 — bisulphide of, 154 
 
 — crystals. 59 
 
 — double muriate of, 523 
 
 — mordants of, 519 
 
 — muriate of, 59 
 
 — nitrate of, 60, 527 
 
 — nitro-muriate of, 528 
 
 — oxalate of, 525 
 
 — oxymuriate of, 532 
 
 — perchloride of, 530 
 
 — peroxide of, 519 
 
 — per-salts of, 529 
 
 — protochloride of, 522 
 
 — proto-salts of, 522 
 
 — salt bath, 313 
 
 — sesqui-salts of, 526 
 
 — sesquioxide of, 519 
 
 — single muriate of, 524 
 
 — solution of, 523, 531 
 
 — solutions of proto-salts of, 524 
 
 — spirits, 519 
 
 — stannic, chloride of, 530 
 
 — sulpho-muriate of, 630 
 
 — tetrachloride of, 330 
 
 — pulp, blue, 166 
 
 white, 166 
 
 Toluen, 222, 675 
 Toluidine, 177 
 
 — discovery of, 177 
 
 Trimethylic rosaline, bimethyl iod- 
 
 hydrate of, 202 
 Tungstate of soda, 119 
 Turkey red, 321 
 experiments on, by Dr. Schut- 
 
 ZENBERGER, 323 
 
 tops, bleaching cotton stockings 
 
 with, 52 
 
 — reds, discharges on, 594 
 Turmeric, 418 
 Turning, 654 
 
 Tyrian purple, 2 
 
 TTLTRAMARINE, 158 
 
 — and madder extract, specimen, 643 
 
 — blue, chrome black, and dichromate 
 
 of lead, specimen, 641 
 
 — manufacture of, 159 
 
 — materials for manufacture of arti- 
 
 ficial, 160 
 
 — silica, 161 
 
 Ultramarine, soda, 161 
 — specimen of, 160 
 Urtica utilis, 63 
 Usitatissimum linum, 57 
 
 V 
 
 AT blues, detection of, 672 
 
 — decomposed, 90 
 
 — Indian or potash, 480 
 
 — soda or potash, go 
 Vats, indigo, 471 
 
 — pastel, 479 
 Variolaria dealbata, 369 
 Vegetable and animal origin, colouring 
 
 matters of, 228 
 
 — fibres, 17 
 
 distinguishing from each other, 
 
 65 
 
 — thickenings, 17, 66 
 Verdigris green, 545 
 Vermillion red, specimen, 153 
 Vesuvine, 220 
 Violaniline, 183, 209 
 Violet, amaranth, 380 
 
 — Ballo's, 679 
 
 — Dorothea, 676 
 
 — Hofmann's, 192, 613, 676 
 specimen, 194, 677 
 
 — imperial, 190 
 
 — Lauth's, 677 
 
 — methyl diphenylamine, 678 
 
 — Paris, 676 
 
 — or mauve, Perkin's, 187 
 
 — Poirrier's, 676 
 
 — Wanklyn, 676 
 Violets, detection of, 667 
 
 — naphthylen diamine, 221 
 
 — naphthylamine, 221 
 Viscosimeter, Steilmann's, 71 
 Vitriol, blue, 547 
 
 — green, 535 
 
 — Roman, 547 
 
 TX7ASHING-MACHINE, 308 
 
 Water, phenylated, 215 
 
 — test for impurities, 10 
 Water-glass, potash, 112 
 
 — soda, 118 
 
 Wau (German), 408 
 War cotton, 30, 34 
 Weld, 408 
 
 — cultivation of, 408 
 
 — dyeing with, 413 
 upon cotton, 414 
 
 — mode of extracting colouring mat- 
 
 ter from plant, 409 
 Weights, 701 
 
 — and measures, decimal or metric, 699 
 Whinberries, 509 
 
 White, 639 
 
 3 B 
 
■ > j|Wli» ■ »» * > *» «H« * » **» * 10*0 * w q^i i rt* ■ 4fjMMm* 
 
 392 
 
 Y 
 
 730 INDEX. 
 
 White colouring matters, 150 
 
 — warps, green on, 101 
 
 slates and modes on, 100 
 
 Whortleberries, 509 
 Wine, hermitage, 259 
 
 — red colouring matters o f -> r 
 Woad, 89, 453 
 
 — vat, applications of, 90 
 Wolfram, 542 
 Wongsky, 421 
 Wood, Bahamas or Jamaica, 332 
 
 — Bahia, 332 
 
 — Brazil, 331 
 
 colouring glucoside, 335 
 
 decoction or liquor of, 337 
 
 — caliatur or cariatur, 341 
 
 — Californian, 332 
 
 — cam or kambe, 342 
 
 — Cuba, 405 
 
 — Madagascar, 341 
 
 — Nicaragua, 332 
 
 — palisander, 512 
 
 — Pernambuco, 331 
 
 — santal, 340 
 sanders, or red sanders, 339 
 
 — sapon or sappan, 332 
 
 — Sierra Firma, 332 
 
 — St. Martha, 331 
 
 — yellow, 405 
 
 Brazil, 405 
 
 Woods, red, 331 
 Wool, 82, 652, 674 
 
 — bleaching, 86 
 
 — merino, 84 
 
 — reds on, 92 
 
 — sulphur from, 85 
 Woollen fibre, 83 
 
 Woollen yarn and fabrics, recipes in 
 connection with, 88 
 
 bleaching, 88 
 
 Woollens, colours on, 89 
 Working, 654 
 Wouw (Dutch), 408 
 
 VANTHEIN, 4 24 
 
 Xanthin, 424 
 Xanthopurpurin, 249, 252 
 Xanthorrhea hastilis, 218 
 
 ARN, green for, 95 
 
 — white bleaching linen, 58 
 Yellow, 94, 628, 635, 638 
 
 — Beige. 94 
 
 — campo-bello, 674 
 
 — colouring linen yarn, 59 
 
 — coralline, 217 
 
 — dark, from Persian berries, speci- 
 men, 612 
 
 — Fol's, 674 
 
 — French, 678 
 
 — Indian, 425 
 
 — naphthalin, 221 
 
 — pale, from Persian berries, speci- 
 men, 612 
 
 Yellows, aniline, 209 
 
 — detection of, 664 
 Yokin, 418 
 
 ^INALINE, 210 
 
 Zinc, anhydrous oxide of, 151 
 
 — chloride of, 523, 545 
 
 Printed at the Chemical News Ofiice, Boy Court, Ludgate Hill, London, E.C. 
 
ERRATA AND ADDENDA. 
 
 P. 93, line 3 from bottom, for " saleratus " read " bicarbonate of soda." 
 
 P. 226, line 8, for " lime " read " iron." 
 
 P. 239. The formula of alizarin is now considered to be C14H8O4. 
 
 P. 438, line 14 from bottom, wad " a perfectly definite nitrogenous principle." 
 ,, line 6 from bottom, for " chemistry " read " compounds." 
 
 P. 439, line 22 from bottom, erase " and chlorine." 
 
 P. 440, line 6 from bottom, for " sulphuric acid" read " sulphurous acid." 
 
 P. 447, line 24, for " found" read " formed." 
 
 line 10 from bottom read " in certain animal secretions, such as 
 urine, not merely pathologically, but as a result of ordinary 
 metamorphosis of tissue (see Schunck on the Occurrence of Indigo 
 Blue in Urine)." 
 
 P. 468, line 7 from bottom read " enluminage." 
 
 P. 470, line 19 from bottom read " that trials in practice on the large scale 
 differ from." 
 
 P. 472, line 15 from bottom, for "a&ive " read "process." 
 
 P. 476, note, erase " by porosity through the fibre." 
 
 P. 534, line 3, after " cotton-yarn " insert " it." 
 
 P. 539, line 17, for " nitric acid" read "nitrate of iron." 
 
 P. 553, line 10 from bottom, erase "throws." 
 
 P. 651, line 20, for " chiefly " read " sometimes." 
 „ line 26, for " woven " read " unwoven." 
 
 P. 654, line 6 from bottom :— In an improved machine there are two rollers 
 fixed over the beck. The goods run over one roller, through the liquor, and 
 on the other roller. By reversing the handle the pieces are alternately coiled 
 and uncoiled round each roller. 
 
 P. 665 (Detection of Reds) :— To distinguish saffranin from magenta boil the 
 swatch in alcohol. If it is magenta the solution will appear crimson and 
 transparent, both by reflected and by transmitted light; whilst saffranin solution 
 is rose-colour and transparent by transmitted light, but appears turbid, opaque, 
 and scarlet by refle&ed light. Warm water containing 5 per cent of soap 
 becomes coloured if a swatch dyed with magenta is steeped in it, but remains 
 colourless if the dye be saffranin. If a swatch is steeped in water acidulated 
 with hydrochloric acid, along with a piece of zinc, it will soon be decolourised 
 if the dye is magenta ; saffranin remains unchanged for some time, and then 
 turns a bright yellow. 
 
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