>-»^: THE DYER'S GUIDE. EPITOME OF COLOURS. Colours obtained by Sir Isaac Newton's method of deconqiosing the rays of light, the least refrangible being placed first, the most refrangible last. See p. 18. Red. Orange. Yellow. Green. Blue. Indigo Violet. THE DYER'S COLOURS AND THEIR CHIEF COMPOUNDS. SIMPLE COLOURS. Blue, Yellow, Red, Black*. Red includes Crimson, Scarlet, Maroon, Pink, &c. COMPOUND COLOURS. Green is made with Blue and Yellow. Orange with Red and Yellow. Purple "^ Violet Vwith Blue and Red. Lilac ) Greys with Black, Blue, and Red. TBlue, Yellow, and Black; Olives with -| or (^ Blue, Yellow and Red. * IjLAck, according to the theory of Newton, denotes the absence, and White the prcseHcc of all colours. THE DYER'S GUIDE; COMPENDIUM OF THE ART OF DYEING LINEN, COTTON, SILK, WOOL, MUSLIN, DRESSES, FURNITURE, &c. &c. WITH THE METHOD OP SCOURING WOOL, BLEACHING COTTON, &c. DIRECTIONS FOR UNGUMMING SILK, AND FOR WHITENING AND SULPHURING SILK AND WOOL. AND ALSO im* AN INTROD UCTORY EPITOME OF THE LEAVING FA CTS IN CHEMIS TR Y, AS CONNECTED WITH THE ART OF DYEING. By THOMAS PACKER, DYER AND PRACTICAL CHEMIST. Get arte est un des plus utiles et des plus merveilleux qu'on connoisse." Chaptal. There is no art which depends so much on chemistry as dyeing." Garnett. SECOND EDITION, CORRECTED AND MATERIALLY IMPROVED. LONDON: PRINTED FOR SHERWOOD, GILBERT, AND PIPER, PATERNOSTER-ROW. 1830. Digmzed by the Internet Arghive;. Km 2010 with funding from NCSU Libraries i^ http://www.archive.org/details/dyersguidebeingcOOpacl< PREFACE. To insist on the utility of the present Manual is, as- suredly, superfluous. The favourable reception of the first edition, sometime since out of print, has stimulated the author to revise the work throughout, and to render it more deserving the public approbation. The Appendix to the first edition now forms a part of the Introductory Chapter, to which it naturally belongs ; to the whole have been added such improvements as the present advanced state of knowledge, and particularly chemical knowledge, has rendered absolutely necessary ; and which the prac- tical dyer will find of considerable importance and much utility. The following letter from the late Sir Humphry Davy, the first chemist of the age, appeared in the Preface to the first edition ; it is here again reprinted as some proof of the sufficiency of that learned man's judgment, at least concerning the chemical theory of the art of dyeing. VI No. 16, Berkeley Square, SIR, June 18, 1823. I am very much obliged to you for your liberal com- munication on a subject of my Lectures : I will attend to the information you are so good as to give me in the next Edition. ,-^ I am Sir, Your obliged and obedient servant, H. DAVY. Mr. T. Packer, Stamford Street, Black-Friars Road. The author has only to add, that an Index is now ap- pended to the work, by which every article may be most readily and conveniently found. London, Nov. 1829. ERRATUM. Page 22, line 3, for proximate read ultimate. CONTENTS. CHAPTER I. INTRODUCTORY. PAGE On the different branches of dyeing — On the drugs used in dyeing — On vegetable and animal substances — On substantive and adjective colours, and mordants — And on the leading facts of chemical science as connected with the art of dyeing — On the calico printer's mordant for yellow and red, and on compound colours — On bleaching — On the theory of fast and fugitive colours — On dye-houses and water — Miscellaneous observations 1 CHAPTER II. ON DYEING COTTON. To dye cotton a Saxon or chemic blue — Sulphate of Indigo — Saxon or chernic green — To set a cold indigo vat — Another Indigo vat — To dye cotton a fast green with the cold indigo vat and weld — Another cold blue vat for linen and cotton — solution of indigo for penciling printed muslin, &c. — To dye cotton a fast buff — To dye cotton pink 47 CHAPTER III. ON DYEING SILK. jJkk^ To alum silk — The blue vat of indigo for silk — Another blue vat for silk ** — To dye silk violet, royal purple, &c. — To dye silk lilac — Another process for lilac — Another process for dyeing muslin, &c. lilac — To dye silk a violet or purple with logwood — To dye silk violet with Brazil-wood and logwood — To dye silk violet or purple with Brazil- wood and archil , €)3 CHAPTER IV. ON SCOURING AND DYEING WOOL. 3n the action of alum and tartar upon wool — A pastil or woad vat for blue — To prepare the indigo mentioned in the preceding directions — Rules to judge of the state of the vat — Indications when a vat has had too much or too Uttle lime — To work a vat which is in proper order — On the putrefaction of the woad vat — Methods of dyeing blues — To dye wool with lac-dye, scarlet, or crimson — To dye worsted yarn a crimson — A preparation of archil to finish the crimson — on dyeing wool scarlet — To dye wool maroon — To dye wool yellow — To dye Vlll CONTENTS. PAGE wool brown or of a fawn colour — To dye wool purple, S:c. — To dye wool green — A chemic vat for green woollen — A cheraic vat for blue woollen — To dye wool orange, gold colour, &c. — To dye wool black — Another process for black without a blue ground — To dye wool a grey — Mixture of black or grey with red and blue — On browns, fawns, greys, &c. — On the yellow of Quercitron bark — On a full bright yellow from the same bark — Bancroft's murio-sulphate of tin — To dye wool buff— To dye wool peach — To set an indigo vat for worsted, serge, &c. 70 CHAPTER V. ON DYEING SILK AND COTTON BLACK. To dye silk black for velvets — To dye silk black London process — On dyeing cotton black dt Rouen — To dye cotton black, London process — For dyeing black, particularly cotton velvets, at Manchester — On dyeing silk and cotton black with a blue ground — Another iron liquor — To dye cotton black by using the preceding solution — to dye cotton violet — To dye cotton red — To dye cotton an Adrianople or Turkey red — Miscellaneous observations relative to Adrianople red 105 CHAPTER VI. ON DYEING COTTON AND SILK. To dye skein cotton yellow — On dyeing and re-dyeing cotton furniture yellow — to dye cotton skein a duck's wing green and olive — Of browns, maroons, coffee colours, &c. — Observations on silk — On un- gumming and boiling silk — Whitening — Sulphuring — On aluming silk — Skein silk for yellow — Preparation of annatto for aurora or orange, raoidore, gold colour, and chamois — To dye silk aurora or orange — To dye moidore — Process for orange — To dye silk poppy or coque- licot — A cheaper poppy with annatto and Brazil wood — On dyeing silk a fine crimson — Composition for dyeing silks scarlet or crimson with cochineal — Another process for crimson — Another process for crimson by Brazil wood — Of fine violet — Observations on crimson and scarlet upon silk — On dyeing silk green — On olives — On dyeing silk grey — Nut grey — Black greys — Iron greys — On dyeing silk of a Prussian blue colour — Chromate of lead for yellow on silk or cot- ton — Conclusion 123 Index 153 THE DYER'S GUIDE. CHAPTER I. INTRODUCTORY. On the different branches of dyeing — On the drugs used in dyeing — On vegetable and animal substances — On substantive and adjective colours and mordants, and on the leading facts of chemical science, as connected with the art of dyeing — On the Calico -Printers' mor- dant for yellow and red, and on compound colours — * On bleaching — On the theory of fast and fugitive colours — On dye-houses and water — Miscellaneous observations. The trade of a Dyer is, in this country, subdivided into several distinct branches. Thus we have woollen dyers, who are occupied solely in the colours obtained from cochineal, such as scarlet, crimson, orange, buff, 8fc.; likewise pwrjo/e, ox royal purple, obtained from cochineal and indigo. They are called, also, grain dyers, from the circumstance of the colouring material, cochineal, B 2 INTRODUCTORY. being in small grains *. Yet it ought to be observed, that the term dyed in grain is applied by the public generally in a very different sense, namely, to those cloths the raw material -of which is dyed previously to being spun into thread, or at least before woven into cloth ; and hence such dyes are usually more permanent than those which are dyed after the materials are woven into cloth. This class of dyers generally dye cloth in the piece, or a number of pieces of cloth tacked together, and worked over a winch in a suitable copper. There are dyers who likewise dye worsted and woollen yarn of those grain colours, but they are generally a distinct branch. The yarn is dyed in hanks, upon sticks ; and, when in the copper, the hanks are changed end for end, so that they may be kept even; such changing being performed five or six times to each turn- ing in. ^ ^ There are also silk dyers who are grain dyers. These dye in the skein, chiefly for new goods. Some silk, and some mixed silk and worsted goods, are dyed in the piece. In dyeing cotton, the Adrianople or Turkey Red is, in many cases, a branch of itself, and comes the nearest to what may be called grain or scarlet dyeing upon cotton, because cochineal cannot be applied to cotton to any advantage; yet cotton is occasionally dyed with this material. In woollen another branch consists of the woad dyers. These often superintend the black dye on woollen cloth, • Cochineal was at first supposed to be a grain, which name it still retJuns by way of eminence among dyers. Ure. THE DIFFERENT BRANCHES OF DYEING. 3 as well as the blue from woad and indigo. There is the same distinction among worsted yarn dyers, they having likewise to do slates, greys, &c. Nearly the same may be said of the silk skein dyers. In many places, particularly in the country, browns, drabs, stone-colours, &c. constitute a branch in woollen. The same colours form also a branch in calico and muslin ; but black, in calico and muslin, is a distinct branch. The dyers (whether in London or provincial towns) who keep shops, and take in garments, furniture, &c. to be dyed, are termed by the trade Rag-dyers. There are a few dyers in the metropolis who dye black on woollen, silk, cotton, &c. for the dye-shops, many of these putting all their black out to be dyed. There are one or two dyers famous for dyeing silk stockings black; these constitute a particular branch. Dyeing bombasins black is also another branch. The following constitute also particular branches : black hats, — hats of fancy colours,— fur, — chip and straw, — feathers, — leather, Morocco and Spanish, and kid leather for shoes and gloves. Many other branches of the dye-trade might be enumerated, but more detail does not appear necessary. Concerning all these different branches, one general observation will suffice ; namely, that those who are concerned in them have, for the most part, obtained their knowledge of the art of dyeing, not from theories adapted to explain the different processes, but from practice in that branch in which they are occupied. They usually, therefore, perform those processes whith b2 4- INTRODUCTORY. they have been shewn and told, without any inquiry into the causes which produce the results. There are, it is admitted, exceptions to this, men of general informa- tion and knowledge being occasionally found in the various branches of dyeing, but they are so few, that it may be questioned, when compai'ed with the great body employed in the art, whether they amount to one in a thousand. This is not, however, to be attributed to any indifference in such persons to acquire a correct know- ledge of the art, but is chiefly owing to a deficiency of the ready means of acquiring such information ; which information it is the design of the present Treatise to sujjply; there not being, as far as the present writer knows, any such work, at a moderate price, to be ob- tained in the English language. It is true many of the Cyclopcedias furnish us with much useful information on the subject of dyeing : one of these, Jennings's Family CyclopcBdia, may be par- ticularly mentioned as containing such ; but it is scat- tered about in these dictionaries in various ways, at once troublesome and unpleasant to obtain. Dr. Bancroft's work on the philosophy of Permanent Colours, in two octavo volumes, will also supply much valuable informa- tion ; so also will the edition, some time since published, of Berthollet's Elements of the art of Dyeing, with the addition of valuable Notes by Dr. Ure. Dr. Ure's Chemical Dictionary is also very useful to the dyer, as well as many detached papers in several of our English publications. A Treatise on Printing a?id Dye- ing Silks, §c. lately pubhshed by H. M'Kernan, is also valuable, and should be consulted by the curious in this ON THE COLOURS OF DYEING, 5 art. But all these works are expensive, and such as few dyers will be disposed to obtain ; hence the necessity of the present Manual, the author of which has not servilely followed the directions or recommendations of any pre- vious writer ; but from his own practice, a practice of more than thirty years, has laid down such rules as he knows to be at once practical and efficient. At the same time he thinks it right to state, that he has not only consulted all the works mentioned above, but also Hellot, Macquer, 8fc. adopting all that appeared essen- tial in these, and giving such additions as accord with the present improved state of chemistry and dyeing ; and, as far as was possible, in the limits prescribed for this work, so that it may be within the reach of every dyer in the kingdom, as well as every journeyman and apprentice in all the various branches of this truly exten- sive and mysterious art, as carried on in London, Nor- wich, Yorkshire, Gloucestershire, and various other parts of the British dominions. The author has, in treating of the various matters to be dyed, adopted nearly the same arrangement as that which appears in the Title, taking Cotton first, in con- sequence of its having the least affinity for dyeing bodies. He has taken Silk next, which has a greater affinity for many dyes, and, when dyed, yields colours more per- manent than cotton. Wool he has not placed entirely last, although many of the colours which it receives from the dyer are com- plex. The blacJc dyehig of cotton and silk is placed after the processes of black for wool, as likewise the Turkey red, %c. these being naturally difficult to perform. b3 b INTRODUCTORY. While and b/ack have been considered colours by dyers, and with propriety, black forming a part of slate, grey, &c. White is seldom pure ; in proportion to its clearness and purity will the colours be with which it is dyed. In regard to black dye, and particularly cotton black dye, the author does not know any simple and concise theory, consistent with chemical principles. He flatters himself, however, that from his extensive experience, his observations are founded on interesting facts. Cotton, for instance, will take fast blues from the cold indigo vat ; this vat, with the combination of iron, and in a heat no greater than the hand can bear, will easily pro- duce all shades of grey, slate, &c. Many of these colours may be done by logwood instead of the blue vat, and in the same heat of the dye bath ; so cotton likewise, whether in pieces or skeins, may be dyed brown, fawn, drab, &c. in consequence of the great affi- nity which cotton has for acetate and sulphate of iron. With respect to black, it should be also observed, that few substances are known which yield by themselves a good black. The juice of the cashew nut communicates, however, a black colour, which resists not only washing, but even boiling with soap and alkaline leys. It is used for marking linen. The Toxicodendron yields a juice which produces nearly the same effect. Some other vegetables also produce black dyes, but all of them in such small quantities as not to be available for the purposes of art ; nor do they, besides, produce blacks equal to those formed in the dye-house. Blue, red, and yelloio are admitted to be three dis- DRUGS APPLICABLE TO DYEING. 7 tinct colours. In many of the browns, red and yellow are combined naturally in the drugs from which they are produced, and so they are in logwood. Blue, red, and yellow, are developed by iro?i, whether in the state of an acetate or sulphate. It may be useful, before we proceed any farther in noticing the theories of dyeing, to give a brief descrip- ^.ion of the DRUGS APPLICABLE TO DYEING. Alum, or Potash-sul/phate of alumina, is a concrete salt, composed of alumina or clay, potash, and sulphuric acid. It is found native in some places ; but the greatest part of the alum of commerce is prepared by a peculiar management of schistose pyritic clays, usually denominated alum ores. Alum is made at Civita Vec- chia, in Italy, and also at many other places on the con- tinent ; at Hurlett near Glasgow, at Whitby in York- shire, &c. Its form and appearance are both too well known to need being described. Its chemical composi- tion is as follows : sulphate of alumina, 36.70 ; sulphate of potash, 18.88; and water, 44.42— together 100. The alum called in commerce Roch alum, said to be obtained from Roccha, in Syria, is in smaller crystals than com- mon alum, and has a reddish hue, but does not appear to be essentially different from the common alum. Com- mon alum requires sixteen parts of water, at a tempera- ture of 60°. to dissolve one of it ; but there is another kind not generally made or known, containing soda instead of potash, and hence with propriety named soda- sulphate of alumina, which is soluble in less than its B 4 8 INTRODUCTORY. own weight of water, and which, on this account, may be- come valuable in some processes of dyeing. — Ure. Acetate of Alumina is prepared in large quantities for the calico printers, by decomposing alum with acetate of lead, or more economically with aqueous acetate of lime, having a specific gravity of about 1.050, a gallon of which, equivalent to nearly half a pound avoirdupoise of dry acetic acid, is employed for every 2^1bs. of alum. A sulphate of lime is formed by complex affinity which precipitates, and an acetate of alumina floats. — Ure. Archil, Archilla, Rocella, Orseille, or Litmus, is said to be a whitish lichen growing upon rocks in the Canary and Cape Verd islands, which yields a rich purple tincture, fugitive, but extremely beautiful. It is brought to this country as it is gathered ; it is prepared here for the dyer, by grinding it between stones, so as thoroughly to bruise but not to reduce it into powder ; it is moistened occasionally with a strong spirit of urine, or urine itself, mixed with quick lime ; in a few days it acquires a purplish red, and at length a blue colour ; in the first state it is called archil, in the latter lacmus or litmus. The dyers rarely employ this drug by itself, on account of its dearness and the perishableness of its beauty. Its chief use is to give a bloom to other colours, as pinks, &c. Cudbear is also manufactured in this country from archil, and is in repute for dyeing various shades, from pink and crimson to a mazarine blue ; it is said these co- lours are very permanent. Argol, or Tartar, is a crystalline substance depo- sited in wine casks during the fermentation of the wine. DRUGS APPLICABLE TO DYEING. 9 from the juice of the grape, in which it exists in consi- derable abundance. It is an impure supertartate of potash : that is, potash combined with a superabundant quantity of tartaric acid. Argol is found in commerce of two colours, white and red. Cream of tartar is the same substance freed from colouring and other extrane- ous matter. Blood. See Adrianople red. Bran acts in some peculiar way on coloming matter, but scarcely on the mordants. It seems to loosen and remove the colouring matter ; as also to alter its hue in some cases, an effect obvious in the bran pinks. — Ure. Chlorine. See Oxy muriatic acid. Cochineal is the female insectof the coccus cae^i found on the cactus coccineUifer and cactus opuntia, Prickly pear or Indian fg, natives of South America, the West Indies, and other tropical regions. The female of the insect is the true cochineal ; in her full sized, pregnant, and torpid state, she bears so small a proportion to her former or creeping state, that her antennae, legs and proboscis are scarcely discernible ; her whole appearance is that of a whitish berry, and so it was formerly regarded. This insect is found in a wild state in Mexico, Georgia, South Carolina, and some of the West India Islands, feeding on several species of the cactus ; but in some of the Spanish settlements, as well as in Mexico, the insect is domesticated, and fed on the cactus coccineUifer, which is cultivated for the purpose, on Avhich it attains a much larger size than in its wild state. Cochineal is also obtained from the East Indies; but East Indian cochineal has not yet attained the quality of that pro- B 5 10 INTRODUCTORY. (luced in the West Indies and America. Its use, as a colour for dyeing many shades of red, &c. is great and important. Copper is also used in dyeing, in the state of a sul- phate or blue copperas, a nitrate, and also as an acetate. See Verdigris. The Gall or Bile of animals consists of a sapona- ceous bitter, yellowish fluid, secreted by the liver, and found in the sac usually called the gall-bladder. It is sometimes preferred to soap for cleansing cloths by the dyer and the scourer. Galls are excrescences produced on the quercus in- fectoria, a species of oak growing throughout Asia Minor. The gall grows on the shoots of the young boughs, and is produced by an insect, the cynips quer^ cusfoUi ; this insect punctures the tender shoot with its sting and deposits its egg in the puncture ; the egg is soon hatched, and the irritation of the maggot feeding on the plant produces the wen or gall-nut. When the nuts are gathered before the worm within changes to a fly, and not yet having eaten its way out, they are of a dusky green colour, and are called in commerce blue galls, and are by far the best. Those collected after the fly has eaten its way out have a hole in each, are of a whitish yellow colour, considerably lighter than the blue- galls, and of an inferior quality : they are brought to this country chiefly from Aleppo. They are used in large quantities in the arts, principally for dyeing, and making ink. They contain a large quantity of Tannin and Gallic acid. Indigo is a well known deep blue substance, obtained DRUGS APPLICABLE TO DYEING. 11 from the Indigqfera tinctoria or Indigo bearing plant, a native of the East Indies, which is propagated by seed and will thrive in most tropical climates ; hence we have good indigo from South America, the East Indies, Carolina, &c. The chief criterion of the goodness of indigo is, if, when cut with a knife, it exhibits a reddish copper-like appearance ; where this shade is not, or only very slight, the indigo is of inferior value. It is pre- pared by macerating the leaves in water, whence is ob- tained the blue feculence or indigo. Indigo is insoluble in water, but soluble in sulphuric acid, hence a solution of it in this acid, forming a sulphate of indigo, is well known in the art of dyeing. The best indigo is that called Flora, which floats in water, all the other kinds sink in that fluid. The constituent parts of indigo are Carbon, "73.22, Ni- trogen 11.26. Oxygen 12.60, and Hydrogen, 2.92,=100. When indigo is digested in concentrated sulphuric acid, it is converted into a peculiar blue substance, com- monly called sulphate of indigo ; this colouring matter has been, however, lately named Cerulin, by Mr. W. Crum, who has made many experiments on it ; (see notes to Bertholet, vol. ii. p. 357. et seq.) he observes that cerulin dissolves more abundantly in sulphuric acid than water ; but this does not prove the formation of a com- pound entitled to be called sulphate of indigo ; that, such a solution differs in no respect from that of resins in acids or in alcohol. Another substance has been also obtained from indigo by Mr. Crum, of a purple colour, which he calls Phenicin ; it dissolves both in water and alcohol. B 6 12 INTRODUCTORY. Iron rarely in its metallic state enters into the mani- pulations of dyeing, but its sulphate, muriate acetate^ &c. as well as its oxides contribute largely to the dyer's art. Sulphate of Iron, or green coppevas, as it is com- monly called, is too well known to need description ; it is in green crystals of different sizes, and is used for various purposes in dyeing, &c. Peracetate of Iron, or Acetate of Iron, forms a reddish-brown uncrystallizable solution, much used by the calico printers, and is prepared by keeping iron turnings or pieces of old iron for six months immersed in redistilled pyrolignous acid. It may be also prepared in a more expeditious way by boiling filings of iron with the acid. Lac dye and lac lake are two articles now regularly imported from the East Indies, and employed for dyeing scarlet. They both appear to be the colouring matter of seed-lac, obtained from it in India by a process not gene- rally known. Both these articles are in lumps or cakes of a dark-reddish or blackish colour. Muriatic acid, or sinrit of salt, as it was formerly called, is obtained from common salt or muriate of soda, by distillation with sulphuric acid. When this acid is pure it is perfectly colourless, but it generally has a yellow hue arising from a little iron. It gives out, at all tem- peratures, a large quantity of a fuming suffocating gas of a peculiar smell. Its usual specific gravity is about 1.160. For the basis of this acid see Oxymuriatic acid. Nitric acid is composed of oxygen and nitrogen: it is usually obtained from nitre, (the chemical name of which DRUGS APPLICABLE TO DYEING. 13 is nitrate of potash,) by distilling three parts of it with two of sulphuric acid. When pure, nitric acid is a colourless, extremely sour, and corrosive liquor. Its specific gi'avity is 1 .42 ; it always contains more or less water, which modifies its specific gravity. It is usually coloured with nitrous acid gas. It forms a variety of compounds with numerous other bodies. Aqua fortis is this acid diluted more or less with water ; when strong it is called double, when weak single aquafortis. For Nitrogen, see forwards. NiTRo-MURiATic ACID, or AQUA REGiA, is a mixture of nitric and muriatic acids. It is usually made by dissolving sal ammoniac or common salt in nitric acid. When the former is employed the usual proportion is one of the salt to four of the acid ; but equal parts will be neces- sary to dissolve platinum. Aqua regia is the only men- struum which will dissolve gold. Orpiment, realgar, or sulphuret of arsenic has been lately applied to the purposes of dyeing a yellow colour. Sulphur may be combined with arsenic in dif- ferent proportions. Realgar is red, and occurs native in Germany and Switzerland ; it is also produced by art. Orpiment is commonly produced by art and is of a yel- lowish colour ; native orpiment is also occasionally found ; it is of a bright lemon colour. Oxymuriatic acid, or as it is now more correctly termed chlorine, from its yellowish green colour, is an elastic gaseous fluid of a pungent disagreeable smell, and highly injurious to animal life, even when largely diluted with atmospheric air. Mixed with hydrogen, and ex- posed to light, they combine and produce a sour com- 14 INTRODUCTORY. pound called muriatic acid gas; this gas is greedily absorbed by water, which takes up 480 times its bulk, and has its specific gravity increased from 1 to 1.210. Thus dissolved in water it forms the liquid muriatic acid mentioned in a preceding article. Chlorine forms combination, besides, with several other bodies ; many of its combinations are termed oxymu- riates, or more properly, chlorides : some of these are extremely useful in bleaching, dyeing, &c. The muriatic acid appears to be the only acid of any consequence into which oxygen does not enter. Oxide is the combination of oxygen with some base, without being in the state of acid ; it is most commonly applied to the combination of oxygen with metals ; most of the different rusts of metals are oxides. As oxygen combines with the metals and other bodies in different proportions, its combinations are distinguished by dif- ferent prefixes, thus : protoxide denotes an oxide con- taining the least quantity of oxygen ; deutoxide the next larger quantity ; tritoxide the next ; and peroxide the largest possible quantity of oxygen in the compound when it is not acid. For Oxygen see forwards. Pot-ashes and Pearl-.-vshes (one of the fixed alka- lies) are both impure carbonates of potash obtained from the ashes of innumerable vegetables, over which water is poured which dissolves the salts, and by evaporating the water leaving the salt, a dry powdery white mass is obtained. The chief difference between pot-ashes and pearl-ashes consists in the superior whiteness of the latter, and in the former being of a more dirty colour, and more caustic than the latter ; hence it is not so highly DRUGS APPLICABLE TO DYEING. 15 saturated with carbonic acid. For many purposes in the arts such caustic potash is to be preferred. Quercitron, or American-bark is obtained from the querctis nigra or black oak, a native of North Ame- rica. It is used for dyeing yellow, and was brought into notice by Dr. Bancroft, who obtained the exclusive privilege of using it as a dye by an Act of Parliament, passed in the 25th year of the reign of George III. Safflower, bastard-saffron or carthamus, is obtained from one or two plants, species of the carthamus genus, natives of the South of Europe and the Mediterranean coasts. This dyeing material consists of two colouring substances, a yellow and a red. The former is of little value, the latter which is soluble in alkalies forms, by precipitation with acids, a beautiful red pigment some- times used for silk dyeing, but more commonly in the preparation of rouge. Soda, called sometimes mineral alkali, is another of the fixed alkalies ; it forms the basis of common salt, that being a muriate of soda ; soda, under the name oi barilla, is used in making soaps, and also in dyeing. Sulphur, or Brimstone, is scarcely used for dyeing in its crude state, but when combined with oxygen form- ing sulphuric acid, as well as when that acid is com- bined with various bases, as iron, alumina, &c. it becomes of great importance in this art ; see Sulphuric acid. Sulphate of Iron, see Iron above. Sulphuric Acid was for many years, and still is called by the vulgar, oil of vitriol, because it was for- merly obtained from green vitriol or sulphate of iron, but the more simple and ingenious processes of modern che- 13 16 INTRODUCTORY. mistry have superseded the old methods ; sulphuric acid is now obtained by burning sulphur ^vith a certain portion of saltpetre in large leaden cisterns. The acid fumes sink into the water placed at the bottom of the cistern, the water being afterwards boiled away : the acid is afterwards purified by retorts, placed in a sand heat. The specific gravity of good sulphuric acid should be 1.85. Sumach is the production of the rhus coriaria, a shrub which grows naturally in Syria, Palestine, Spain, and Portugal. It is cultivated in the two last countries with great care. Its shoots are cut down every year quite to the root, and after being dried are reduced to powder, and thus prepared for the purposes of dyeing, &c. Su- mach bears a great resemblance, as an astringent, to galls. Sumach alone gives a brown and a fawn colour, but cot- ton stuflTs impregnated with acetate of alumina take a durable yellow from it. Tartar, see Argol. Tin, dissolved in nitric or muriatic acid, forms solutions of gi'eat importance in many processes of dyeing, par- ticularly scarlet. These solutions are called respectively nitrate and muriate of tin. Turmeric is a root obtained from a plant growing both in the East and West Indies. The root is used chiefly for dyeing yellow ; but it is a fugacious colour. Verdigris is a crude acetate of copper, obtained by exposing copper plates to the husks, &c. of grapes, which containing considerable acetic acid, the acid com- bines with the surface of the copper plates, forming a blueish green rust, which is scraped off, and forms the verdigris of commerce. A still more complete acetate of DRUGS APPLICABLE TO DYEING. J 7 copper is obtained in distilled verdigris, which is in elegant green crystals. The best verdigris is made in France ; some is now also made in this country. Weld, sometimes called improperly Woulds, dyer's- weed, or Reseda luteola, is a plant found wild, in this country, but cultivated for the purposes of the dyer ; it is much used for yellows. WoAD, or Pastel, is obtained from a plant growing in various parts of Europe and also in this country ; it is the Isatis tinctoria, and is cultivated with care for the dyeing matter which it affords, and which is obtained from the leaves of the plant, collected and prepared in a particular manner. Woad gives a full-bodied and fast blue to wool, yet not very bright, so that it is usually mixed with indigo *. Besides the preceding substances we may mention that annatto is used for dyeing several colours ; kermes, mad- der, and Brazil-wood for reds ; log-wood for purple and black ; peach-wood ^OY inaroon, See. -, fustic, dyer s-hroomy saw-wort, French-berries, &c. for yellow ; walnut-root, and the outside green shell of the nuts for browns. We may also mention prussiate of potash, acetate of lead, commonly called sugar of lead, and oxide of manganese, as occasional articles used for various purposes by the dyer. Several other substances are also used in dyeing, which we cannot enumerate ; some are mentioned in the subsequent pages. We may, however, name cam-wood, bar-wood, redsanders, and myrobolans. We ought also * For the cultivation of Woad in England, see Parish's paper in vol. xii. of the Bath Society's Report, or Tilloch's Mag. vol. xxxviii. 18 INTRODUCTORY. to observe that how desirable soever it may be to have all woods for dyeing, in powder, in order to obtain the gi*eatest quantity of colouring matter from them by de- coction or otherwise, yet, as in a powdered state they are much more likely to be adulterated than in ch'ijis, it is most advisable to purchase them in this last state ; log- wood in particular ought never to be purchased in powder. On the Component Parts of Vegetable and Animal sub- stances. In order more correctly to understand the theory and practice of dyeing, it is essential that the pupil should become acquainted with the nature of the substances upon which and with which he must necessarily operate. We shall not enter into the theories of lig/tt and of colours, as propounded by Sir Isaac Newton, as well as many illustrious chemists, who have already done so much for the art of dyeing, but shall simply refer to such writers as Ure, Bancroft, Berthollet, Brande, &c. from whom may be learnt what is of most importance to be known concerning this curious subject. We may just add, however, in regard to light, that Sir Isaac Newton proved it consists of rays differing from each other in their relative refrangibilitit s. By causing light to pass through a hole in a window-shutter into a darkened room, and receiving that light on a glass prism, the rays, in passing through the prism, not only became refracted, that is, thrown out, of the rectilinear direction, but also separated into seven distinct colours, namely, red, orange, yellow, green, blue, indigo, and ON VEGETABLE AND ANIMAL SUBSTANCES. 19 violet. The red being the least refracted and violet the most. If these prismatic, or primary colours, as they are usually called, be divided into 360 equal parts, the red rays will occupy 45 of these parts, the orange 27, the yellow 48, the green 60, the blue 60, the indigo 40, and the violet 80, and, what is very remarkable, these colours, when mixed in the proportions here set down, produce white. This may be readily proved by mixing seven powders of the colours and quantity men- tioned, or by painting a wheel with the same proportions of the different colours and making it revolve rapidly. But it should be noted, that, in either case, the white will not be so pure and delicate, as that produced by the mixture of the rays of light. Upon these phenomena is founded the Newtonian theory of colours. Thus green bodies reflect the green rays and absorb the others. All the rays are reflected by white bodies, and absorbed by those which are black. It is, notwithstanding, highly necessary that the learner should know that portion of modern chemistry which will lead him to the best secrets of his art, and hence assure him of that which was only before conjecture. And it cannot be sufficiently impressed upon him, that if our theory be not true, we work from wrong data ; we may, it is true, approach the truth ; be right in some things and wrong in others, and our uncertainty and mistakes will be accordingly; yet the most complete dyer must be he, who with extensive practice combines a knowledge of the true principles of his art, to which modern che- mistry is, doubtless, the key. It is scarcely necessary to insist further on the im- 20 INTRODUCTORY. portance of a knowledge of the constituent parts of vege- table and animal bodies, as well as those inorganic sub- stances with which chemistry has so largely to deal ; but it will be seen, in the course of our subsequent obser- vations, what difficulty there is in dyeing cotton of a red colour, similar to that produced by cochineal on wool; how, in dyeing cotton yarn an Adrianople red, the in- testinal liquor of the sheep, and the dung and the blood of the same animal are used, and have been found so important by the dyers of Asia ; hence the colour is called the Adrianople or Turkey red. It is found by experience, and particularly in hot climates, that substances containing ammonia (volatile alkali) quite developed, have the property of raising and rendering more intense the red colours. It has been found, too, that the bones of animals retain the colour of madder very strongly, when they have been given that colouring material ; and the vivacity of the colour has been attributed in such cases, it is presumed with truth, to the ammonia which the bones contain. There are, therefore, in regard to vegetables in par- ticular, some things, the nature and properties of which it is absolutely necessary that the dyer should under- stand : for want of a knowledge of one of them, it is a fact that losses are very often sustained to a serious amount. It may seem surprising, but the author has not seen in any w^riter on dyeing or chemistry, a pro- per method of working the pastil or woad vat; nor how to renew and work it down, again and again, with an assurance that it will be neither decomposed nor spoiled ; and w^hich, for want of a proper knowledge, it has often ON VEGETABLE AND ANIMAL SUBSTANCES. 21 been. We shall therefore endeavour to give some direc- tions by which those fatal and expensive disasters may be avoided. Although, at first sight, it seems easy to distinguish the three kingdoms of nature from each other, yet there is such an imperceptible transition from one to the other, that it will be difficult to give such a definition as shall embrace all the individuals of each, and, at the same time, exclude those of the other kingdoms. On examin- ation, indeed, we do find that there is in fact no natural distinction of this kind ; and that there is scarcely a func- tion common to vegetables and minerals which some of the animal tribe do not enjoy, and vice versa. Yet it must, however, be noted, that most animals have the power of voluntary loco-motion, and are thus rendered peculiarly different from all other bodies which we find upon or in the earth. The substances constituting vegetable differ from those constituting mineral bodies, in their being of a more complex kind ; and though vegetables are extremely sus- ceptible of decomposition in various ways, not one can be, by any art, synthetically produced. Yet, although what are called by chemists the proximate constituents of vegetables are numerous, such are water, starch, sugar, gum, gluten, wax, oil, camphor, resins, colouring matter, extractive matter, several acids, &c. &c. all of which are capable of being decomposed, the ultimate constituents of vegetables are very few ; the chief are carbon, hydrogen, and oxygen; some aSoxd. nitrogen ; in some are traces of sulphur, potassa, lime, soda, mag- 22 INTRODUCTORY. jiesia, silica, &c. ; in nearly all vegetables are traces of iron; in many manganese. As the proximate principles of vegetables are chiefly carbon, hydrogen, and oxygen, it will be useful to in- quire how vegetables obtain these materials. Water, which is composed of hydrogen and oxygen, is a ready source whence both its constituents may be obtained ; and it is concluded that it is decomposed in the glands of vegetables, assisted by solar light, and becomes fixed in them in the state of oil, extract, mucilage, &c. The greatest part, however, of vegetables consists o{ carbon, or, to make ourselves more intelligible, ^wre cAflrcoa/; tlie carbon, notwithstanding its solidity in the shape of charcoal, most readily combines with oxygen, and hence it forms, as carbonic acid, a small portion of atmospheric air, from which source the carbon of plants is in part at least derived. Another source from which plants derive their carbon is the earth, and decaying vegetable matters ; the dung'of animals supplies also some of the constituents of vegetables. Indeed, in the application of dung and other matters, so as to promote the healthy and vigorous growth of vegetables, does the science of agriculture chiefly consist. It appears, however, that nourishment is received principally, if not entirely, by plants in a liquid or gaseous form. It should be noticed too, that few, if any, healthy vegetables will grow any where except in light, a powerful stimulant at all times, not only to plants but to animals ; such are its effects, that many dyes in cloth are materially altered, nay, sometimes destroyed by it. ON VEGETABLE AND ANIMAL SUBSTANCES. 23 Animal substances thus diflfer from vegetables : they afford a considerable quantity of ammonia, (which is, it is now known, a compound body consisting of hydro- gen and nitrogen), and very fetid products, either by the action of fire, or by the putrid fermentation. They also putrify more readily and speedily than vegetables, and give out a very disagreeable smell. They also contain a con- siderable quantity oi nitrogen, \!iiQ^ presence of which con- stitutes the most striking peculiarity of animal compared with vegetable bodies ; but as 'some vegetables contain nitrogen, so there are certain animal principles into the composition of which nitrogen does not enter. The chief ultimate principles then of animal matter are car- bon, hydrogen, oxygen, and nitrogen; hwt phosphorus and sulphur are also often contained in it. Lime also exists in animal bones and shells in considerable quantity, usually, however, in combination with the phosphoric and the carbonic acid. The c\v\ei proximate principles of animal matter are blood, albumen, gelatine, colouring matter, milk, bile, lymph, urine, skin, muscle, horn, hair, fat, cerebral substance, shell, and botie, &c. The differences between vegetable and animal bodies appear to depend upon animal matter containing nitrogen in much greater abundance than it is found in vegetables ; and hence the decomposition of animal matter by de- structive distillation is characterized by the presence of ammonia, which is formed by the union of the hydrogen with the nitrogen ; and it is sometimes so abundantly generated as to be the leading product : thus when horns, hoofs, or bones are distilled by themselves, a quantity of solid carbonate of ammonia and of the same substance 24 INTRODUCTORY. combined with a foetid oil, and dissolved in water, are obtained. Hence the preparations called salt and spirit of hartshorn and animal oil. The principal animal fluids are blood, milk, and bile. The blood, soon after it is taken from the living animal, separates into two parts, one called the crassamentum, which is red, and the other serum, which is a fluid, and of a pale straw-colour ; the crassamentum is a more firm and consistent mass than the serum, by which it is usually, when cool, surrounded. Milk consists of serum or whey, butter, which while floating on the milk is called cream, and curd or cheese, which has the leading properties of coagulated albumen. The bile, as has been before stated, is a saponaceous fluid consisting chiefly of albumen, soda, a bitter resin, water, and some other saline matter. Fat, in the dead animal, is merely animal oil in a concrete or hai'dened state. The principal animal solids besides bone, are albumen, gelatine, andjibrin. These substances, in certain states of concretion and combination, form all the solids of animals, and are separable from each other by easy analysis. By whatever means we deprive animal substances of their nitrogen, we reduce them to a state similar to that of vegetables. The muscular fibre, or Jlesh as it is usually called, when excluded from the air, but particu- larly if in contact with water, parts with its nitrogen, and is converted into a substance resembling spermaceti, which in its analysis agrees with vegetable expressed oil. When vegetables and animals are deprived of life, their various parts, and especially their fluids, sooner or ON VEGETABLE AND ANIMAL SUBSTANCES. 25 later, spontaneously assume processes which terminate in their total decomposition. The earlier stages which lead to their decomposition are iexvaeA fermentation. Of this there are three kinds ; the first, or vinous fermentation, takes place in vegetable juices which contain a con- siderable quantity of sugar, such are the juices of the grape forming wine, of the apjjle forming cycler, &c. In this fermentation a considerable quantity of carbonic acid gas is disengaged ; this gas is very destructive to animal life, no one can live for a minute in it. If, after the vinous fermentation is completed, the liquor be ex- posed for some time to atmospheric air, another fermen- tation takes place, oxygen is absorbed, and the liquor becomes vinegar, hence called the acetous fermentation. The putrid fermentation generally takes place in animal bodies very soon after death, so that neither of the other processes, certainly not the vinous, the acetous rarely, becomes a condition of animal matter. The chief product of the vinous fermentation is an intoxicating, colourless, volatile, and highly inflammable liquor called alcohol; in common language rectified sj)irits of wine. It may be obtained by distillation from wine, cyder, perry, brandy, &c. &c. ; and from whatever liquor it be obtained, when freed from extraneous matter, it is in every case the same. Alcohol consists of hydro- gen, carbon, and oxygen. Its usual specific gravity is 825, water being 1000. After vegetables have passed through these fermenting processes, the decomposition continuing, unless checked by extraneous means, the remainder of their constituents become separated, many of them being volatilized in the 26 INTRODUCTORY. form of gas, and nothing remains but a black or brown residuum called mould, consisting of carbon, some salts, a little oil, and extractive matter. In the decomposition of animal substances, we per- ceive the union of hydrogen and nitrogen forming am- monia; the combination of carbon with oxygen produces carbonic acid ; and nitric acid arises from the union of oxygen and nitrogen. A quantity of hydrogen is also extricated in the form of gas, carrying off with it sulphur and phosphorus, which produce together the disagreeable smell arising from animal putrefaction. Nothing now remains but a portion of carbon mixed with phosphate of soda and phosphate of lime. Hence we see that, by the processes of fermentation, complex bodies are converted into more simple substances, and that nature restores, in the new combinations, the principles which she had borrowed from the atmosphere for the formation of both animals and vegetables ; and that she accomplishes a perpetual circle of ever-changing being, at once demonstrating the fecundity of her re- sources, and the grandeur and simplicity of her ope- rations. On substantive and adjective colours, and the mordants, Sfc. used in dyeing; and on the leading facts of chemical science as connected with this art. The substances commonly dyed are either animal, as wool, silk, hair, leather, and skins of all kinds ; or vegetable, as cotton, fax, hemp, ^c. Great differences exist be- tween the affinities for colouring matter possessed by ON SUBSTANTIVE AND ADJECTIVE COLOURS. 27 these substances, so that a process which perfectly suc- ceeds in dyeing wool may fail when applied to cotton. Wool has generally the strongest affinity for colour; silk and other animal substances come next ; cotton next, and hemp and flax last. Of the numerous known dyes, few can be applied to either animal or vegetable fibre without some preparation beyond that of cleansing the stuff, and immersing it in the dyeing hquor. When colours can be fixed on cloth without any previous preparation, they are called sub- stantive colours, such is indigo ; when they cannot be so fixed, but require to be saturated with some preparation, such as acetate of alumina, or a metallic oxide, &c. they are called adjective colours ; of this kind are mad- der, cochineal, &c. The substances with which cloths are impregnated, previously to being dyed, are called mordants, because they are supposed to bite or lay hold of the colour which is applied. The chief difference between vegetable and animal sub- stances is, that animal (as for instance wool) contains a small portion of carbon, and a large quantity of hydrogen and nitrogen ; while vegetables contain a very large pro- portion of carbon, less hydrogen, and, in general, no nitrogen. It is the interest of every dyer to acquire as much information as possible concerning the nature of alum, iron, carbon, nitrogen, hydrogen, the alkalies, acids, &c. in order to prevent or obviate the consequences of an incorrect application of these agents in the various de- partments of his art, and also to apply them with the greatest success. We shall, therefore, enter a little into c 2 28 INTRODUCTORY. the nature and combinations of some of these bodies, and state some of the leading facts with which the modern discoveries in chemisti-y have made us acquainted. Carbo?}, or charcoal, is considered an elementary body, because, as yet, no means have been found adequate to decompose it ; it forms the skeleton of vegetables or their woody fibre. We must now direct the attention of the reader to oxygen gas, the discovery of which was made by Dr. Priestley in the year 1 774, and by him called delphogis- ffcated air ; the most important discovery that was, per- haps, ever made in chemistry. When a metal is exposed to atmospheric air, at almost every temperature, it loses its metallic lustre, and acquires the form and appearance of an earthy substance. If this change be produced in a given quantity of air, the oxidatioti can only be carried on to a certain degree ; and on examining the air which remains, we shall find that it has lost the whole of its oxygen, and that nothing remains but nitrogen gas. What was formerly called the calcination of metals is nothing but the process of their union with oxygen, which is now therefore properly called their oxidation. If charcoal be mixed with the metallic oxide, and a suitable heat be applied to the mixture, it will unite with the oxygen and form cai'bonic acid, which will fly off in the form of gas, while the metal will assume its metallic form. From this we learn that oxygen is a part of atmospheric air, and that nitrogen constitutes another portion of the same air. Ammojiia is a combination of nitrogen and hydrogen. Combustion, or the burning of any combustible body, cannot take place, at least under CHEMICAL SCIENCE OF THIS ART. 29 ordinary circumstances, without the presence of oxygen. Nitrogen gas, (called by its discoverers azotic gas), con- stitutes about three fourths of atmospheric air ; the other fourth consists of oxygen, besides a small fraction of carbonic acid gas. Oxygen decomposes and destroys all fugitive colours. Oxygen is, besides, the basis of almost all the acids, and hence is one of the most universal agents in nature. Hydrogen, formerly called inflammable air, was dis- covered by Mr. Cavendish in 1767; it is called hydrogen, because it is one of the component parts of water ; or, more properly, it is the base of water. It is obtained in the most pure state from the decomposition of water by means of metals, thus : pass one hundred parts of water through a red hot iron tube, a gun barrel for instance, fifteen parts of hydrogen gas will be produced, v*hile the inside of the tube will be found converted into an oxide, and to have gained eighty five parts in weight. Again, when eighty five parts of oxygen gas are burned with fifteen of hydrogen gas^, both gases vanish, and one hundred parts of water are the result. Hydrogen gas, when in a pure state, is about fifteen times lighter than atmospheric air; hence its use for inflating balloons. Hydrogen, if inhaled, destroys animal life ; combined with nitrogen, it forms ammonia, or the volatile alkali, as we have before stated. We have mentioned the Jixed alkalies in a preceding section. We may add here, that by the discoveries of Sir Humphry Davy, in the year 1807, the base of caustic, or Tpuxe potash, is now known to consist of a light, white me- tallic substance, to which the name oi potassium has been c3 30 INTRODUCTORY. given; it is of the consistence of soft wax; at a freezing temperature it is hard, brittle, and solid ; when thrown upon water it instantly takes fire, hydrogen gas escapes, and an oxide qfpofassium, or caustic pot- ash, is produced. The pot-ash and pearl-ash of the shops we must not forget, are combinations of carbonic acid and pot-ash, hence they effervesce with all the acids; but caustic pot- ash, containing no carbonic acid, combines with any of the acids without effervescence. The SODA, as obtained from barilla, is a carbonate of soda ; pure soda, or caustic soda, was, till the discoveries of Sir Humphry Davy, supposed to be, as well as pot- ash, a simple substance. It is now, however, known to consist of a metallic substance of the colour of lead, but, nevertheless, lighter than water; upon which, when throvvn, it produces, like potassium, violent action, yet does not, in general, like potassium, inflame. It is called sodium; pure soda consists therefore of sodium and oxygen, hence it is an oxide of sodium. These discoveries of the composition of the fixed alkalies are of infinite im- portance in the arts. The alkalies contain some very striking properties : Their taste is acrid, burning and urinous. They generally change the blue colours of vegetable infusions green. IVJien mixed with silex or flint, by exjjosure to great heat they form glass, and they render oils miscible with water, and hence combine ivith them forming soaps. They effervesce (when combined ivith carbonic acid,) with many other acids, and form neutral salts with all the acids. The volatile alJcali or a?nmonia, on exposure to air, flies entirely away. Pot-ash, either in its caustic CHEMICAL SCIENCE OF THIS ART. 31 state, or in that of a carbonate, absorbs moisture from the air, and Hquifies. While soda, on the contrary, and many of its combinations, effloresce in the air; they, nevertheless, effervesce, and combine with the acids in a similar way to pot-ash. We have mentioned how pot-ash is obtained in a preceding section. Soda is commonly procm'ed from the ashes of marine plants ; the barilla of commerce is obtained, it is said, in Spain, chiefly from many species of the salsola, or salt-wort. Barilla is an impure sub- carbonate of soda, it is used largely in the manufacture of soap. We now proceed to notice the nature of acids. They excite aparticidar sensation on the palate, which we call sour. They change the blue colour of vegetables red. All of them, except the carbonic acid, effervesce with the volatile as well as the fixed alkalies when in the state of carbonates, as they are most commonly found in commerce. Oxygen is the principle of almost all acids; their difference depends upon the base combined with the oxygen : thus oxygen combined with carbon or pure charcoal, forms carbonic acid; with nitrogen the nitric acid; with s\x\\)h\xx \\\q sulphuric acid, ^c. Sfc. Gas is a term implying the same as air ; but as the term air, when used, is liable to be misunderstood for the air of the atmosphere, which is, as we have seen, a compound body, the term gas is more appropriately ap- plied to all elastic fluids of a specific kind. Thus we say carbonic acid gas, oxygenous gas. The difference between carbonic acid and carbonic acid gas, and oxygen and oxygenous gas, consists in the latter being com- c 4 32 INTRODUCTORY. bined with heat only, and in the state of air, while in the former they are fixed in some body, as in carbonate of pot- ash and oxide of lead, in both which cases the carbonic acid exists in a fixed state, or combined with the pot-ash, and the oxygen is in a fixed state, or com- bined with the lead. We may now treat of carbonic acid gas, which is thus produced, as well as in many other ways : when charcoal is burned in oxygen gas, exactly sufficient for its com- bustion, both the charcoal and oxygen disappear, and an elastic fluid is found in the vessel, which is equal in weight to both. This air or gas is carbonic acid gas ; it combines with lime, the alkalies, and pure or burnt magnesia ; it constitutes a considerable portion of the weight of chalk, limestone and marble, as is readily seen by comparing these bodies before and after their conversion into quicklime. It is frequently combined with hydrogen. The gas with which the streets are now- lighted is chiefly carburetted hydrogen. Carbonic acid gas has the following properties. It extinguishes flame, and, like nitrogen and hydrogen, kills animals immersed in it. It is heavier than common air, and may therefore be poured out of one vessel into another like water. Cider, wine, beer and other fer- mented liquors owe their briskness to the carbonic acid which they contain ; soda-water also owes its briskness entirely to the quantity of carbonic acid gas which it con- tains, a small quantity of heat being sufficient to give the acid the gaseous state. SuljiJiKr has been mentioned before ; it is well known to be a very combustible substance ; it is found in great quan- CHEMICAL SCIENCE OP THIS ART. 33 titles throughout nature; the sulphur of commerce comes either from Italy or Sicily; or from the isle of Anglesea, where it is obtained from the smelting of sulphuret of copper; the best, however, comes from Sicily. It is, sometimes, found pure ; but often combined with some of the metals, forming sulpJmrets. It is also frequently obtained by the decomposition of animal and vegetable substances ; it is sometimes found combined with hydro- gen (hence called sulphuretted hydrogen), in the human stomach, more frequently in the intestines. Sulphur combined with a small dose of oxygen, forms a volatile suffocating acid, called the sulphureous acid ; with a large dose it forms sulphuric acid, or oil of vitriol. For the nitric and muriatic acids, see a preceding section. We may, however, mention here, that nitric acid has the peculiar property of staining the scarf skin of the human body a dull yellow, of such permanence, that it can scarcely, by any means, be destroyed, it usually remaining till the skin wears or peels off. The principal vegetable acids are the tartaric and the acetic. The tartaric acid exists in superabundance in tartar, and particularly in cream of tartar, which is nothing more than a purified tartar. See argol in a preceding section. The acetic acid constitutes the vinegar both common and distilled ; it is found in a very concentrated state in the shops, under the name of aromatic vinegar. It is also now obtained in large quantities, and of great strength from wood by distillation, or burning, in vessels, adapted for the purpose, hence called the jiyr^^^S^^^^ ^^^^' ^"* essentially the acetic acid. This last is now used by c5 34 INTRODUCTORV. calico-printers to make acetate of iron. See a preceding section. Alumina, or earth of alumina, sometimes called argil, is soft to the touch, adheres to the tongue, and hardens in the fire, contracting its dimensions : it constitutes the greatest part of clays. With sulphuric acid and pot-ash, it forms the common alum of the shops. Alum dissolves in about sixteen times its weight of cold water. For acetate of alum see alum in a preceding section. Agriculturists and agi'icultural chemists know that alumina constitutes three eighths or more of a fruitful soil ; some vegetables, likewise, contain this earth in their composition. Iron is also a component part of many soils, particularly those in which a red colour is pre- dominant ; hence it is, probably, a component part of all di'ugs used for browns, fawns, and blacks. It will be seen what affinity cotton has for iron in the dye of huff* upon cotton ; and it seems reasonable to conclude that this metal not only produces the black, grey, and brown hues, but, with lime, forms a component part of the drugs themselves which give the brown dyes. It may be here also mentioned, that the red colour of the blood has been by many chemists supposed to arise from the iron which it contains ; Mr. Brande, however, does not, from his own experiments, conclude this to be the fact. The blood of animals is, nevertheless, occasionally used for dyeing, as will be seen under Adrianojjle red. See • What are called iron moulds in cotton, linen, &c. are, it is well known, nothing but the marks of a 6«^ colour, usually left by ink and other matters which contain iron : acids, of course, dissolve, and discharge these buff colours ; the oxalic acid does so without decomposing the cloth. CHEMICAL SCIENCE OF THIS ART. 35 KiRWAN on Manures, Sfc. and Davy's Agricultural Chemistry. From the acids or oxygen combined with alkalies, earths, or metals, almost innumerable mordants, as we have seen, are formed ; and upon the correct and proper application of these to the cloth or other matters to be dyed, depends the goodness and permanence of the co- lours. The dyer cannot, therefore, be too scrupulously attentive to this portion of his art. In dyeing the student ought also to remember, that the material to be dyed combines intimately, in numerous in- stances, with alumina or other mordants ; in the case of alumina it, in some instances, takes up from one twelfth to one fourth of its weight of alum, leaving the alum bath nearly tasteless. So also will rich extract of American bark, or even weld, when the proportion of weld is in weight more than two to one of the wool, form a triple com- pound with the cloth and alum, of permanent duration. All these preliminaries the author considers of the first importance to be understood, and he has, therefore, mentioned them again and again. For so doing he is sure that he shall be excused in the dye-house, although not perhaps by the critics, whose candour he nevertheless respectfully solicits. We now proceed to the application of mordants. In regard to muslins and calicoes, the alum is to be mixed with gum and carried to the piece, as will be described below in the Calico-Printer's mordant, and then immersed in the dye-bath : it thus receives the base or mordant. If the base be alum and the dye-bath madder, then, where the block strikes the pattern with the alumine c 6 36 INTRODUCTORY. base, the colour will come out red; the other parts will clean and bleach white. If alum and iron form the base, the colour will be purple ; if iron alone be applied, and galls, sumach, logAvood, &c. are the component parts of the dye-bath, then it will be black. The Calico-Printer s mordant or base of alum for yellow and red goods, either for printing or dyeing ; and on compound colours. Take one gallon of soft and pure water, of a heat of 150°, three pounds of common alum, one pound and a half of sugar (acetate) of lead ; mix these together, and let them stand for two or three days, so that they may incorporate, often stirring them during that interval ; then add two ounces of pearl-ash, and the same quantity of clean powdered chalk or whiting. After a time the clear liquor, now become an acetate of alum, must be drawn off. When used, it is thickened either with paste, flour, or gum arable, or Senegal ; four pounds of either of the gums to each gallon of liquor*. A block or a press similar to a copper-plate press for paper, but much larger, and having the copper plates in proportion, is employed to spread the acetate of alum from a utensil * ^'Acetate of Alumina is now most frequently made for the calico-printers by dissolving alum in a solution of crude acetate of lime, (pyrolignite) ; a gallon of the acetate, of specific gravity, 1.050 or 1.060, being used with two pounds and three-quarters of alum. A sulphate of lime is formed, which precipitates, while an acetate of alumina mixed with some alum floats above. The acetate of alumina employed as a mordant for chintz, is still commonly made by the mutual decomposition of alum and acetate of lead."— C/re's Berlhollet, vol. ii. p. 331. ON BLEACHING LINEN, COTTON, &C. 37 called a sieve, which is, however, not porous, while a boy or girl called a Teerer, works it smooth ; when smooth on the sieve, the printer applies his block, and charges it with the acetate of alum ; the block thus charged, is correctly put on the cotton cloth, which is laid upon a blanket spread upon a table ; it is then struck with a mallet once or twice, by which, or by the pressure of the rolling-press, if copper-plate, the acetate of alum is driven into the pores of the cloth. The cloth thus pre- pared, is hung up in a hot stove, and dried by a high degree of heat. The goods are now ready, if for red, for the madder ; and if for yellow, for the weld copper. Sometimes, however, lately, the colour is previously pre- pared, and applied at once in more instances than are prudent. To the above mordant, M'Kernan adds three ounces of sulphate of copper, omitting the potash ; and he adds, " When the colour is wanting on the scarlet cast, omit the sulphate of copper." Wool readily takes the alum at a boiling heat ; common alum is in many instances proper for wool ; and in others, where it might be improper, it is corrected by the use of argol or cream of tartar. Yellow and red produce orange ; red and blue, pur- ple ; but upon cotton, a scarlet, purple, or crimson can- not be produced in any way equal to those colours in wool or silk. Yellow and blue form the green. On BleacJdng Linen, Cotton, Sfc. We cannot enter with much minuteness into this part of the subject, more especially as the art of bleaching is 38 INTRODUCTORY. usually a separate one from that of dyeing. Yet as in fact the arts of dyeing and of bleaching depend in a great degree on the same principles, some notice of bleaching, in a treatise on dyeing, seems absolutely necessary. Linen, cotton, and other cloths, were for ages deprived of their colour, in other worcb, bleached, rendered white, by a tedious process. Thus, the article to be bleached being boiled in a solution of pot-ash, was washed, and then spread on the gi'ass in a field, watered occasionally, and, thus exposed to the atmosphere for two or three months, became white. This method is, however, in pai't, if not now entirely, dispensed with. M. Berthollet, an ingenious French chemist, to whose valuable work on dyeing we have before alluded, employed what was then called oxygenated muriatic acid, now chlorine, to perform in a few days what before took months to accomplish. His method was as follows. To six pints of powdered oxide of manganese he added sixteen of muriate of soda, (common salt) and twelve of concentrated sulphuric acid diluted with an equal quantity of water. These were placed in a leaden retort and distilled : the product was oxygenated muriatic acid, or chlorine, which being con- ducted to a vessel containing the material to be dyed, produced the same effects as the former tedious process, and bleached as much, in two or three days, as was before done in two or three months. This process has been since much further improved by the use of a combination of chlorine with lime, called chloride, or oxymuriate of lime. This article is at present used in almost all the bleaching grounds in the United Kingdom. It appears, therefore, that upon the use of the agent, chlorine, does the expedition ON FAST AND FUGITIVE COLOURS. 39 and whiteness of modem bleaching principally depend. Yet it ought, nevertheless, to be stated, that although, in the hands of scientific and judicious persons, chlorine is one of the most powerful agents in bleaching that ever was discovered, still, in the hands of bungling and ava- ricious persons, it may contribute greatly to the destruc- tion of the cloth ; and therefore, even now, a demand is occasionally heard for the old method of bleaching. These processes constitute the art of the bleacher ; the dyer has seldom any thing to do with them except in piece-goods or rough cambric, which he has sometimes to dye black as they come from the bleacher's in a state which they call once boucJced; and sometimes he has them just as they come from the weaver ; in which case, if for black, they need not be bleached white, but should be boiled in pot-ash, to take out the grease, &c. On the theory relative to fast and fugitive colours. Ma,ny attempts have been made by chemical philoso- phers to account for the permanence or want of perma- nence of various colours, when imparted to cloths and other bodies as a dye. Among these, Hellot, D'Apligny, and others of the old, and Berthollet, Bancroft, Henry, and others of the modern school, maybe men- tioned. The power of resisting vegetable acids, alkalies, and soap, and, above all, the action of air and light, consti- tutes the durability of a colour. But this property has a very unequal standard, according to the nature of the colour and the species of the stuff. 40 INTRODUCTORY. There is no obscurity in the action of water, alkaUes, acids, and soap : for a solution is effected by means of these agents, or a small portion of acid or alkali unites to the combination, which forms the colour. But this is not the case with the action of light and air. Till lately, however, it was not known in what this action consisted. Of the two principles which compose atmospheric air, it is only the oxygen gas which acts on the colouring particles. It combines with them, and thus impairs their colour or makes them fade. But its action is soon chiefly exerted on the hydrogen which enters into their compo- sition, and it thereby forms water. This effect may be compared to a feeble combustion. Hence the carbon, which enters into the composition of the colouring par- ticles, becomes predominant, and the colour usually passes to yellow, dun, or brown, or other appearances. Light promotes this decomposition of the colounng particles, which frequently takes place only with its con- currence, and thus it contributes to the destruction of the colour. Heat also favours the same result, but less effi- caciously so, unless it have a certain intensity. It is concluded, therefore, that colours are more or less fixed in the air, according to the greater or less ten- dency which the colouring particles have to undergo this change*. Hence the utility of mordants in rendering fugitive colours /a*^. * BerthoUet. TO PROVE THE COLOURS OF DYED STUFFS, &C. 41 To prove the colours of Dyed Stuffs, 8(c. The natural proofs of a dye's being effectual, are ex- posure to the air, to the sun, or to rain. If the colour be not changed by such exposure after twelve or fourteen days, it may be considered as fixed. These proofs are not, however, adapted to every colour : for some resist the action of air, light, and rain, yet are nevertheless in- jured by certain acids. There are also colours which do not resist the natural proofs and yet remain unchanged by acids. Colours may be arranged in this respect in three classes : the first class is tried with alum, the second with soaj), the third with tartar. For the proof with alum, half an ounce of this salt must be dissolved in a pint of water in an earthen pipkin, and into this liquor is to be put half a quarter of an ounce of the dyed thread or stufi", the whole being boiled about five minutes ; it is then to be washed clean with water. Thus are tried crimsdn, scarlet, flesh-colour, violet, ponceau, peach- blossom, different shades of blue, and other colours bor- dering on these. The next proof consists in boiling a quarter of an ounce of soap in a pint of water, with half a quarter of an ounce of the dyed stuff' or thread for five minutes. With this proof all sorts of yellow, green, madder-red, cinnamon, and similar colours are to be tried. The proof with tartar consists in boiling one ounce of that salt, previously powdered very fine, with a quarter of an ounce of dyed thread or stuff', in a pint of water for five minutes. This proof is used for all colours border- i2 INTRODUCTORY. ing upon fallow, or hair-brown. — Journal of Science, Vol. xxii. 219. But notwithstanding these general rules may be given for dye-tests, yet so many are the niceties in this art, that, after all, nothing but long practice combined with scientific knowledge, will enable the dyer to become in this respect, a complete and successful artist. On dye-houses and the water proper for dyeing. The dye-house should be as spacious as possible, ac- cording to the quantity of work intended to be done in it ; it should be also as near as possible to a clear run- ning stream. The floor should be a mixture of lime and cement, and sufficiently inclining, so that water, the old contents of the vats, &c. &c. may run off freely when thrown down. A dyer cannot be too particular in regard to the water which he uses. Some pump, well, and other spring waters, contain iron ; this is -injurious to many colours, while for black, brown, slates, and grey, it is very advan- tageous. It has been supposed that some dyers succeed in dyeing even the very same colour in a superior manner, in consequence of the peculiar purity or other properties of the water which they use. To discover whether water contains iron or not, a little tincture of galls or prussiate of potash must be dropped into it; if a purple or blue tinge be produced in the water, we may be assured that it does contain iron. For dyeing delicate colours, the water, which ought to be chosen for such purpose the purest and best, should 13 MISCELLANEOUS OBSERVATIONS. 'Iv3 be heated with bran in a bag, when much of the contents of the water inimical to dyeing will rise to the top in the form of a scum, and should be taken off just before the water boils. Instead of bran, a little alum will answer the same purpose when it is not inimical to the colour intended to be dyed. The boiling point of water is at the degree of SIS*' of Fahrenheit's thermometer ; the freezing point is at 32" of the same instrument ; blood heat is at dS^. Miscellaneous observations. The limits and price of this manual preclude the possi- bility of our giving plates to explain some of the machi- nery and utensils which are now employed in dyeing. To inform a dyer what kind of coppers, casks, and vats are necessary, would seem to be superfluous ; and the pupil may soon acquire such knowledge in the dye-house. Should a dyer find it his interest to undertake a branch of his art of which he has not any previous knowledge, he had better engage a man who understands it ; if, how- ever, he thinks himself competent to manage it, but is unacquainted with the best modern utensils appropriated to that particular branch, he had better get a dyer's labourer who has been used to it ; a man of sufficient in- telligence may be found with due encouragement to per- form this part. It may just be added, that lire's Ber- thoUet and Mr. M'Kernans work, both contain numerous explanatory plates of the utensils and machinery which are described and recommended in those works. 44 INTRODUCTORY. All solutions and decoctions of B)a:::il tvood, logwood, fustic, Sfc. should always be prepared in the same quan- tity and proportion, and one measure be invariably set apart for each. This observation is meant more parti- cularly to apply to drugs in stock, always kept in a state of preparation ready for any process or work which may occur. The drugs just named may be kept in a prepared state ; but weld boiled will not keep, nor will some others which are mentioned in the body of the work. Weld, as it will not keep, should be used thus : a cop- per in proportion to the size of the work should always l>e used ; and as weld will bear boiling and re-boiling, it can be boiled by the half bundle or more according as it may be wanted, whether you work little or much. If you are exact and near in your estimate, practice will soon render you perfect in any branch. It should be observed too, that to dye to pattern cannot be the result of a receipt, without a great latitude be left for the judg- ment. The most difficult part of dyeing is that of light drabs, stone drabs, Sfc. Nothing but practice will qualify you for this and all pattern dyeing : the way, and the only good way to ob- tain practice, is to work with all possible regularity. In the dyeing of fancy cloths in the clothing disti'icts of Yorkshire, Gloucestershire, and other fine cloth manu- factories, the mamifactiirers who dye their own cloths, as well as dyers of the greatest eminence, always num- ber, measure, weigh, and time all the component parts of their various processes of dyeing. Such in fact ought MISCELLANEOUS OBSERVATIONS. 45 to be the universal practice ; and then a person of ordi- nary abilities may soon be able to perfect his processes and obtain the best results. Hence, however, it is very necessary that the dyer should have a competent knowledge of chemistry and drugs, that he may be able to judge of the goodness of the articles which he uses, and of the numerous and ex- traordinary combinations into which they enter. To chemistry, in particular, every able and scientific dyer must be largely indebted ; for this reason it is that we have endeavoured, in this introductory chapter, to sketch some of the most important facts in this universal and interesting science. In possession of these qualifications, and working upon the above plan, the dyer can never be far from the de- sired result in all his processes. His deviations, if any, will be few, as from his knowledge, he will soon perceive the first approach of any incorrectness, and be able to adjust it generally without much inconvenience. The chemical terms now introduced into treatises on dyeing are chiefly taken fi-om the Greek language, and are used in such a manner as to convey, by their ety- mology, an idea of the nature of the substances to which they are applied. Oxygen implies the producer of acid ; hydrogen, the producer oi water; nitrogen, the producer of nitre, &c. The term gas has been explained above. Caloric is a term used by chemists for heat ; but caloric is used in a more extensive signification than the term heat, thus : although a gas might possess no sensible heat, yet being in a gaseous state, it is assumed to con- tain a certain portion of caloric which keeps it in its 46 INTRODUCTORY. gaseous state ; the same observation will apply to liquids whether aqueous, oleous, or metallic. All the measures mentioned in this work unless other- wise described^ are those usually called in this country WINE MEASURE, ond not those which have been intro- duced by a late act of parliament, called imperial MEASURES. CHAPTER II. ON DYEING COTTON. To dye cotton a Saxon or chemic blue — Stdphate of indigo — Saxon or cliemic green — To set a cold in- digo vat — Another indigo vat — To dye cotton a fast green with the cold indigo vat and weld — AnotJier cold blue vat for linen and cotton — Solution of indigo for penciling printed muslin, ^c. — To dye cotton a fast buff — To dye cotton pink. We refer the reader to the preceding chapter for many observations relative to cotton, with which, in order to understand correctly the best method of dyeing this ma- terial, it is necessary that he should become acquainted : indeed, the whole of that chapter ought to be well studied by every one desirous of becoming an expert dyer. To dye cotton of a Saxon or chemic blue. This is performed with the sulphate of indigo thus : — put into a brown stone glazed earthen pot four pounds of good sulphuric acid, add to it twelve ounces of good indigo finely powdered, stirring the mixture very quickly 48 ON DYEING COTTON. and frequently ; break the lumps, if it should get lumpy before it is thoroughly mixed, with a glass rod, or with a stick, the bark of which has been taken off: if for wool or silk, the solution will be fit for use in forty-eight hours, but if for cotton it will not be fit for use till the acid is neutralized by an al/cali. Some persons, however, use whiting, but this precipitates and wastes the indigo ; others use magnesia, but this is expensive ; some, again, use pure or caustic potash prepared thus — take Ame- rican pot or pearl-ash about seven pounds, put some of it into a brown stone glazed jar, or rather an open pan ; upon the ashes put some quick lime recently burnt, and then alternately ashes and lime, slacking the lime with water as it is put on the ashes ; let the whole stand to- gether for about two hours : provide now another brown stone earthen vessel with a hole in the bottom, of larger dimensions than the other, put into this a piece of coarse linen to prevent the lime, the impurities, or any foreign body from running through the hole, then upon the bottom put some of the previously mixed lime and ashes, well incorporated, and placed gently upon the linen so as to be sure of its keeping its place and letting the liquor pass through clear. As the mixture is put in add some water occasionally, so as to keep it just covered, and leave room at the top for the swelling of the materials, as the lime- especially will increase in bulk. Water must fill the whole, and cover the lime, &c. which will be known by the bubbles ceasing to rise. When it has stood twelve or fourteen hours, water being occasionally added as it is absorbed, some may be drawn out. To determine whether the carbonic acid has entirely ON DYEING COTTON BLUE. ,49 quitted the potash, (and for which purpose the quick-lime, having a greater affinity with the carbonic acid than potash has, is specifically applied,) take some of the fluid in a wine glass and drop a drop of sulphuric acid into it ; if the carbonic acid has entirely combined with the lime, the sulphuric acid will enter the fluid in the glass quietly, and without any other appearance than so much water ; if you still doubt add more drops of the sulphuric acid successively. If the carbonic acid has not entirely left the potash when the sulphuric acid is dropped into the liquor, an eflervescence or fermentation will be seen in it. Whenever this is the case the liquor must be returned to the mixture for a longer time, and, if necessary, more lime be added. When the liquor or ley is fit for use, all of it is to be drawn off", and more water may be added and remain on the ingredients till it is wanted. It is best to keep it close from the air, because as the air contains a certain portion of carbonic acid, the liquor would in time absorb it, and the ley, instead of containing caustic potash, would become a solution of carbonate of potash, and con- sequently not answer the end designed. To know when the alkali of the mixture is exhausted, take a piece of paper stained with the juice of the blue flowers of violets, or the blossom of the mallow, which is thus prepared — pound the blossoms in a glass mortar with a glass pestle, and squeeze the juice into a- tea-cup, then, with a small hair pencil, cover a sheet of white paper with the juice, and dry it for use. All acids will turn it red, and all alkalies will turn it green ; and, there- fore, as long as any of the alkali remains in the liquor, the D 50 ON DYEING COTTON. paper thus prepared will, when immersed in it, be stained green. The comparative strength of such solutions may also be ascertained thus : take a wine-glass full of the liquor, drop into it a few drops of sulphuric acid, stirring it with a glass rod or clean bit of tobacco-pipe, and then apply a bit of test paper ; if it appear green more acid must be added and stirred again ; apply the test paper a second time, if it be still stained green, a few drops more of the acid must be added, and thus continue till the colour of the paper is neither altered to green nor red : the liquor will then be neither acid nor alkaline, but contain a neutral salt consisting of a combination of the acid and the alkali. By adding, however, a few more drops of the .icid, this last will be found predominant, and the test paper, being immersed in the liquor, will be stained red. By treating different leys in this manner, and counting the number of drops necessary to neutralize each, the strongest ley will always be found that which requires the greatest quantity of acid for the purpose. Alkaline leys are also to be judged of by their weight compared with that of water; a wine pint of water usually weighs about sixteen ounces avoirdupoise ; all alkaline leys are heavier than water, and the heavier they are the more alkali they necessarily contain. A wine pint of some of them will weigh more than seventeen ounces. To return to the dyeing of cotton a chemic blue: (to which a knowledge of these chemical processes, as well as of other processes in our work, is essentially necessary,) take some of the blue liquid prepared M'ith indigo and sulphuric acid, as before directed, and put it into a vessel ON DYEING COTTON BLUE. 51 large enough to hold two or three times as much as is intended to be put in, in order that there may be room to stir it ; add some of the potash, or alkaline liquor, by de- grees till, after several trials, the mixture ceases to be sour ; or, if you do not like to taste it, take a small slip of cotton or mushn and dip it in, after having wetted it out in warm water. If the acid be neutralized the cotton will be sound, if not it will be tender when dried : if the acid predominates much the cotton will be as rotten as tinder ; when the cotton is perfectly strong and sound after being dried, the liquid is in a proper state to dye both cotton and muslin. The goods to be dyed must first be wetted out and wrung, then work them in the flat tub with water, with a little of this blue added, and well stirred in proportion to the shade wanted. From half a pint to a pint of the liquid blue is sufficient for two pieces of twenty-four or twenty-eight yards each, if not of a very full pattern. Blue, \^hen dyed, should be dried in a cool stove, and if book-mushns, framed ; furniture should be stiffened, glazed, or calendered. The preceding are essentially the same directions for preparing and dyeing with the chemic blue which were given in the first edition of this work, and which we see no reason to alter. As, however, for silk in particular, ano- ther method has been given in the late work of Mr. M'Kernan, we give his processes below. Sulphate of Indigo. " Take one pound of the best flora indigo in very fine powder, put this into a stone-ware or lead vessel, then D 2 52 ON DYEING COTTON. add gradually three pounds of the best sulphuric acid, specific gravity 1.800; mix well and stir often, and in twenty-four hours the indigo will be dissolved. Adding three ounces of sulphur to the acid, and heating it to 180*^ ; then, when cooled to lOO'^, pouring the acid oif the sediment, and then adding to it the indigo, is considered the best way of opening or dissolving the indigo. When the indigo and acid have been mixed twenty-four hours, add three pints of boiling water ; stir often ; when cold it will be fit for use." To yieutralhe the sulphate of hidlgo. " Take six pounds of alum and dissolve it in two gal- lons of water at 120*^, when dissolved add, by degrees, five pounds of pearl-ashes until the acid of the alum is neu- tralized and the alumine formed, then put the whole on a piece of calico that has been hooked in a square frame, or tied over a vessel ; when the liquor has run off then add one gallon of boiling water on the alumine and stir it up well. When the water has gone through the calico the alumine is fit for use. Then add a part of this alumine to some of the sulphate of indigo until the acid is neutralized." |Mk Sacco?} or chemic green. The same blue vat will do for green ; but it is best to make another by putting only eight ounces of indigo in- stead of twelve to four pounds of sulphuric acid. If the preparation has been made two or three months it is the ON DYEING COTTON GREEN. 53 better, having been often stirred before it was neutralized with the alkaU. Prepare a strong decoction * of old fustic, which should always be ready at hand as a store, keeping plenty ac- cording to the work to be done, including cotton, silk, and worsted goods. Mix some of the chemic blue with the decoction of fustic in the following manner : put into a tub six pails of soft clear water, to which add a pint of the neutralized blue, and six pails of the decoction of fustic ; stir all well to- gether. Some dyers add a little weak alum liquor till it just tastes before they put in the blue ; it should be but little, otherwise it will precipitate the fustic. This mix- ture should stand two hours to settle. The muslin or calico, say two pieces of twenty-four yards each, should, with the usual precautions, be passed through a strong decoction of old fustic or tumeric as hot as the hand will bear. They are then to be taken out and submitted to a quantity of the green mixture above described, in proportion to the fulness of the green re- quired. When finished, whether for the calenderer or glazer, they should be dried in a moderately warm stove. These two colours are very fugitive, especially upon cotton goods ; but sometimes the customer will not go to the price of the fast green or blue, hereafter to be de- scribed. The difference between decoction and infusion should be always care- fully observed : a decoction is made by boiling the ingredient or ingredients in any liquor ; an infusion is that in which the ingredients are put but not boiled. D 3 54 ON DYEING COTTON. To set a cold indigo vat for cotton, Sfc. Put three pounds of slacked lime, sifted, into six quarts or more of boiling water; stir the mixture well for some time, and after it has settled, draw off the clear liquid, to which add three pounds of sulphate of iron, stirring it well till all is dissolved ; let it settle till the next day; have ready a deal cask, because one made of oak would blacken and otherwise injure the dye, in consequence of the affinity between the tannin, &c. of the oak and the sulphuric acid. Put into the cask seventy-five gallons of water, to which add the mix- ture of lime and sulphate of iron ; take now three pounds of indigo, well ground and ready at hand, dissolved in three pints of strong solution of potash, such as was directed to be prepared for neutralizing the chemic blue. Put this solution of indigo and potash into the tub with the water, lime, &c. ; after it is well stirred, and left to settle, it produces a deal of froth^; but the liquor takes a fine green colom-, which turns to blue when exposed to the air. Soda may be used instead of potash, if treated the same way. Soda, it may be observed, forms the usual ley of the soap manufacturer ; and answers for soap much better than potash, because its combinations do not usu- ally absorb moisture from the air : potash, and several of its combinations, do so. Another indigo rat. Take five hundred quarts of water ; indigo seven or eight pounds. The boiler must be iron. INDIGO VAT. 55 Boil the indigo with sixteen pounds of a hquor made with potash and eight pounds of hme. After the lime and potash have been in contact, as in all these instances they should be, from twelve to twenty-four hours, to take away the carbonic acid from the potash, the clear liquor of this mixture is what must be used. The indigo must be previously powdered, and gi'ound extremely fine in water before it is put into the alkaline liquor. The mix- ture must now be added to the five hundred quarts of water, and the whole boiled till the indigo rises to the surface like cream, and till, in striking the bottom of the boiler with a stick, it is found to contain no solid sub- stance. While the indigo is boiling, another eight pounds of lime must be slacked in about twenty quarts of warm water ; dissolve in this lime-water sixteen pounds of sul- phate of iron. The vat being half filled with water, the solution of lime and sulphate of iron is to be put into it ; the indigo solution is now also to be added, ihe vat, being thus filled to within about three or four inch'es of the edge, must be stirred two or three times a day till it is fit for dyeing, which it will be in about forty-eight hours, and sometimes sooner, according to the temperature of the air, by which the completion of the process is more or less accelerated. When the strength of the vat is exhausted, it must be, of course, replenished. If the liquor becomes black, it wants sulphate of iron ; if yellow, lime is required. When the indigo is far spent, more must be added in the same manner as at first. In this vat, as respects the blue dye, if it be for muslin, D 4 o6 ON DYEING COTTON. calico, Sec, die form should be square, about two yards long, one yard to one and a half wide, and from seven to eight feet deep ; the pieces of cloth are to be hooked into a frame. Where much work is done, it will be necessary to have two or three such vats, in order that they may be worked in succession : by stirring them some hours previously to working, the weaker will do for the lighter shades, the stronger for the fuller colours. If the vat is in proper order, the goods always come out green, and turn blue in the air. This should be ascertained by small patterns previously to working the whole. When any goods are dyed in these vats, if not full enough at one dip, they may be left a certain time, and then be dipped again, once or more, as they appear to require it. When they are blue enough, and fully aired, they must be taken from the hooks, and well washed off in two or three fresh clean waters, or at a wash wheel in a clear running stream. When perfectly clean, they are ready for the calenderer or glazer. To dye cotton a fast green, with the cold indigo vat and iveld. After dyeing muslin blue in the blue vat, weld must l^e boiled in the same manner as for fast yellow. The quan- tity of weld to be used, must be according to the fulness of the blue ground, and of what shade the green is to be ; a proportion of alum must also be used. The goods, after being worked in the same manner by the selvage, must be washed olf, and stiffened, if for the glazer, but not if for dress, but be framed by the muslin dresser. COLD BLUE VATS — PENCIL BLUE. 37 Another cold blue vat for linen and cotton. The indigo is to be powdered, and put into warm water with sulphate of iron, in quantity twice the weight of the indigo, to which is also to be added, the same weight of fresh-burnt lime. The water should be only sufficient to mix it thick at first ; keep it stirred ; and, as it becomes dissolved and green under the surface, increase the water, often stirring and trying the mixture, by put- ting in a pattern between the stirrings, at some hours distance, between each pattern, and increasing the water : in twenty-four hours it will be fit for use. Solution of indigo for penciling printed muslin, Sfc. To twenty-five gallons of water, add sixteen pounds of indigo, and thirty pounds of carbonate of potash ; when mixed, and placed over the fire, as soon as the mixture begins to boil, add quick lime, by a little at a time, to render the alkali caustic; then twelve pounds of red orpiment, and boil till it will give a yellow colour to transparent glass. This form is from Haussman, Were the author to make this solution of indigo, he would first make the alkali caustic with lime, and then put the clear liquor to the other materials. Mr. MKernan gives another form foi* pencil blue with indigo: the principal differences between which and the above, consist in adding equal parts of brown sugar and gum Senegal to it, which, in regard to the addition of the gum, is, we presume, a great improvement. d5 S 58 ON DYEING COTTON. Dr. Ure (Notes to Berthollet, Vol. II. page 4<37.) gives a similar form from Vitalis, for topical or pencil blue ; but he adds, it was much used formerly. Another blue, of less permanence but more brilliance, is now pre- ferred ; it is made thus : — Into an earthen pot four ounces of finely ground and sifted Prussian blue are to be put. Over this must be slowly poured, stirring all the while, sufficient muriatic acid to bring it to the consistence of syrup. The mix- ture is to be stirred every hour for a day, and afterwards thickened with from four to eight pots (of two litres each ; a litre French contains about two wine pints ;) of gum- water, according to the shade wanted. To dye cotton a fast buff. Take a brown stone pan or pipkin, glazed. It must not be the common glazed wares, because these ai*e glazed with lead, and the acids will dissolve the lead ; if, therefore, such are used, the lead being dissolved, will be ihixed with the dyeing materials, and sometimes totally spoil the dye. Stone-ware, if used with care, will bear the fire : such ware is usually glazed with muriate of soda or common salt. Having a proper vessel capable of holding from two quarts to a gallon, fill it half-full of strong nitric acid, to which add, in small quantities at a time, either old horse-shoe nails from the farrier, they being the ^ purest iron, or the cuttings of tin^lafe from the tin- man's, for this is also very pure iron, although covered with tin ; but the small portion of tin in the iron is not ON DYEING COTTON BUFF. 59 inimical to the dye. Be careful not to put too much in at a time, nor to stoop near to it while the solution is going on, as the red fumes arising are very noxious ; and if the iron be added in large quantity, so much efferves- cence would be produced, that a considerable part of the liquor would be thrown over the top of the vessel. When this solution is prepared in haste the air is greatly contaminated, and therefore it is best to prepare it long before it is wanted, and slowly, by dropping hourly small quantities of the iron into the acid, and then little if any perceptible fumes will arise. Continue this process till, by stirring with a glass rod or tobacco-pipe, you find the iron dissolves more slowly : by keeping a little iron at the bottom, and occasionally adding the acid, you may always have this preparation at hand. It is to be used thus : — having a copper of hot water ready, put a part of it to some cold in a flat tub till the mixture is as hot as the hand will bear ; then, according to the paleness or fulness of your pattern, add some of the solution of iron, and mix it well by stirring : begin with about half a pint for two pieces of twenty-four yards each : it is best to add a smaller quantity than is neces- sary first, as you can make another addition as yoU' please, but, if you add the solution in excess, to diminish it is by no means so easy. Now, having ready a flat tub with water of as hot a temperature as the hand will bear, put into it a clear solution of pearl-ash, and have also ready another tub of clear cold water to wash off in ; then pass the pieces (always taking care to have them well wetted out in one of the tubs of hot water before either the solution of iron or pearl-ash is put into either D 6 60 ON DYEING COTTON. of them) through the solution of iron six or seven times, edging them over by the selvage to keep them even ; next, folding them first even upon a board, vvTing them out, wash them off and pass them through the solution of pearl-ash ; lastly, wash them off again in fresh and clean water : a permanent and bright buff will be found, and as good a colour as can be dyed upon cotton. We here see what an affinity iron and cotton have for each other when the iron is combined with an acid and the combination in a liquid state. Although the colour is not so beautiful in every instance, yet, be the acid which dissolves the iron what it may, cotton imbibes the iron from it. What is left of the solutions of iron and the pearl-ash may each be kept in a separate deal tub for use. To dye cotton pink. Take saffiower in proportion to its goodness and the quantity of work to be dyed ; put it into pure and clear water ; tread it in the water till the water becomes fully charged with a kind of extractive yellow colour. It is best to put the safflower into a strong linen bag or sack; a sack containing sixty pounds will take a man two days to wash it clean : if done in a clear running stream the yellow colour will of course run away ; if you have a small quantity in a tub it must be let out at a plug- hole, which every flat tub should have. The safflower must he worked or trod till all the yellow colour is got out of it, or the pink to be obtained from it afterwards tvill not be bright. ON DYEING COTTON PINK. 61 When the safflower is thoroughly washed, take it out of the bag and put it into a deal tub or trough, and add to it pearl-ash in the proportion of six pounds to one hundred pounds of the safflower, which should be weighed before it is wetted. Let the potash be well dissolved in water ; pour part of the clear solution off, and mix it tho- roughly with the safflower ; after having stood for some time strain the liquor through a cloth or sieve into ano- ther deal trough. The whole solution of pearl-ash should not be put in at once, but at different times. If there should be reason to believe that the safflower will yield more colouring matter by a farther addition of the solu- tion of pearl-ash, such additional solution may be made. The water for the solution and the solution to the saf- flower should both be applied cold. Carbonate or mild potash is better than the caustic. By putting the solu- tion of pearl-ash on the safflower at different times it will be readily seen when the fluid passes through the cloth or sieve free from colour. The colour is of a cherry hue, and is resinous, there- fore the water dissolves but little of it; the carbonate of potash is added to dissolve this resin. To overcome the influence of the pearl-ash, which tinges the red of a yellow colour, some cream of tartar must be finely powdered and dissolved in boiling water, and added to the liquor when it is nearly cold. In the South of France lemon juice is used. The colour, being thus raised by the cream of tartar, is now to be mixed with cold water in proportion to the fulness of the pattern desired, and the cloth must be worked six or seven times in it, as in other colours. 62 ON DYEING COTTON. What is left of the colour must be taken up with some skein cotton, and dried ; this may be added to water upon another occasion by saturating the acid with a solu- tion of pearl-ash, which will abstract the dye from the cotton. The solution of tartar will again redden the colour from the yellow of the pearl-ash ; this must be done if any remain, for it will not keep in a fluid state. We shall not here describe any other process with cotton till we have treated of wool and silk. For dyeing cotton black, and some other colours, see the chapters V. and VI. CHAPTER III. ON DYEING SILK. To alum silk — The blue vat of Indigo for silk — Another blue vat for silk — To dye silk violet, royal purple, ^c. — To dye silk lilac — Another process for lilac — Ano- ther process for dyeing 7nuslin, ^-c. lilac — To dye silk a violet or purple tvith logwood — To dye silk violet with Brazil wood and logwood — To dye silk violet or purple with Brazil wood and archil. To alum silk. Forty or fifty pounds of alum being dissolved in a cop- per of hot water, the solution is to be poured into a tub containing forty or fifty pails of cold water ; during the mixing of the solution of alum with the water it should be well stirred lest the cold water should crystalhze the alum and spot the silk ; when, however, this happens, dipping silk in warm water will dissolve the alum. The silk should be alumed cold, for, if hot, the lustre of the silk will be injured. Alum is used for certain reds and yellows but not for blue. See also chapter VI. When silk is deprived of its gum so as to acquire the greatest possible degree of whiteness, it is still necessary 1 G4 ON DYEING SILK. to have different shades of white, some yellow, some blue, and others reddish ; these are known under five de- nominations, namely, China white, India white, thread or 7nilk white, silver and a:tiire white. All these whites, although differing from each other by very slight shades, are nevertheless apparent, especially when compared with each other, which will be seen in the processes of dyeing silk. For ungumming and boiling, whitening and sulphur- ing silk, see chapter VI. We have described M'Kernan^s method of preparing and neutralizing sulphate of indigo in pages 51 and 52, to which the reader will be kind enough to refer : the following blue vat is from Macquer. The BLUE vat of indigo for silk. This should be so contrived that heat may be applied to it, which it now mostly is, by steam, as well for woollen woad vats as for indigo vats. For silk, take eight pounds of the finest indigo and six pounds of the best pearl-ash, and from three to four ounces of madder for every pound of ash, besides eight pounds of bran for the whole, washed in several waters to take the flour out. When washed, and the water squeezed out, the bran is to be put at the bottom of the vat ; the pearl-ash and the madder being mixed by bruising them roughly together, are now to be l)oiled a quarter of an hour in a copper containing two- thirds of the vat ; the fire being damped, the liquor is then suffered to rest. Two or three days previous to this the indigo is to be steeped in a bucket of warm water. ON DYEING SILK BLUE. 65 and washed well, the water being changed once or more. Some dyers begin by boiling the indigo in a ley made with one pound of pearl-ash and two buckets of water ; they afterwards pound it in a mortar quite wet, and, when it becomes like paste, fill the mortar with the liquor before boiled, and still hot, stirring it for some time. It is then suffered to stand a few moments, and then the clear is poured off into a separate boiler or into the vat. The same quantity of the mixture is then poured upon the indigo remaining in the mortar and mixed as before ; again the clear is poured off into the boiler, and the operation is repeated till the whole of the indigo is dis- solved in the liquor. The whole of the liquor in the boiler is now to be gradually poured into the vat on the bran at the bottom, adding afterwards the remainder of the composition, grounds and all. After stirring and raking for some time, the mixture is left to cool till it will bear the hand in it, when a little heat is added to keep it in this state, and so continued till it begins to turn green, which is easily known by try- ing it with a little silk. When the green begins to appear it should be stirred with the rake, then suffered to stand till the brown and coppery scum which rises upon the surface shews that the vat is come to ; or, in other words, the preparation of this part of the process is complete. But as it is necessary to be very certain of this, the scum should be well examined ; and if, when blown aside, a fresh scum is immediately formed it is as it ought to be. In this state it is to remain for three or four hours, when a new composition is thus made : — Put as much water as is requisite to fill the vat into a G6 ON DYEING SILK. copper, boiling it with two pounds of pearl-ashes and four ounces of madder as at first. This new liquor is to be poured into the vat, raked and mixed, and being left to stand for four hours it is then ready for dyeing. When a vat or vats are set for green, double the quan- tity of madder must be added. (See Chap. VI.) The size of the vat for the above quantity of indigo, should be about five feet deep, two feet or two feet and a half in diameter at the top, and one foot and a half or two feet in diameter at the bottom : the form of an inverted frustum of a cone ; or of a sugar loaf inverted, with the pointed top cut ofT. In order to produce different shades of blue, the silk intended for the darkest, should be first dipped in the fresh vat and so on to the lightest ; as the vat weakens, the silk should be kept in longer, till the vat, being ex- hausted, serves only for the lightest shades. When it begins not only to be weak but dull, it is then necessary to feed the vat with the following composition : Take of the decoction of pearl-ash with indigo one pound ; of madder, two ounces ; and a handful of washed bran ; boil them together for a quarter of an hour, either in water or a portion of the same vat if yet sufficiently full to afford it ; after this mixture is added, it should be well raked and suffered to rest two or three hours, more or less, before the dyeing is resumed. For the finest blues, however, a fresh vat is the best ; and if only pale blues are required, a vat set on purpose with less indigo will answer better than a sti-ong vat which has been weakened, because though weak it will give more vivid colours. ON DYEING SILK VIOLET AND PURPLE. 67 Another blue vat for silk. Take fifty pounds of good indigo in fine powder ; fifty pounds of fresh slacked stone lime ; one hundred pounds of sulphate of iron ; and five pounds or more of pearl- ashes. Stir often for three or four days till there is a fine copper-colour scum on the top of the liquor in the vat. The vat is of course to be set with water in the usual way. The substance of this form is from M'Kernan; we cannot, however, avoid thinking, that his directions for this vat are very vague. To dye silk a violet, royal purple, &c. Boil archil with water in a copper; the quantity of archil according to the colour required must be from two to four times the weight of the silk. When the archil has boiled about ten minutes the fire must be damped, the archil left to subside, and the clear liquor put into a vessel of a convenient size, in which the silk is to be im- mersed and worked with care. You must have a small corresponding pattern that you intend for purple, which at times you must put into the blue vat to regulate the depth of the archil ground, as the purple is a compound colour, arising from the blue of the indigo and the red of the archil. When the red of the archil is deep enough, you must wash it off and put it into the blue vat with proper precaution. The lulness of the archil ground and the depth of the blue. C8 ON DYEING SILK. must be regulated according to the patterns which are to be matched. To dye silk lilac. Lilac is and should be a bright light shade of violet or purple ; to give it the blue requires great management. The vats being generally too strong, it is best to mix a little of the new rich vat with some pearl-ash in clean cold water, and so prepare a liquor on purpose, by which the lilacs may be blued or reddened at pleasure. When this liquor is first mixed it becomes of a green colour ; the silks therefore should not be dipped till the liquor begins to lose its green colour and inclines to blue. Pearl-ash added to this liquor helps to blue the archil, because the effect of the alkali upon red is to render it violet. Another process for lilac Consists in simply using the chemical blue with archil according to the shade required. Another process for dyeing muslin, 8fC. lilac. This is accomplished by mixing the neutralized chemic blue for cotton with the pink dye of safflower, according to the shade required. To dye silk a violet or purple \oith Logwood. The silk should be alumed and washed. The loff- wood should be boiled in large quantities like fustic, as ON DYEING SILK. 69 was directed for green ; but it should not be kept longer than two or three weeks ; it is far better used cold than hot. To dye silk violet tvitJi Brazil wood and Logwood. The silk must be alumed and cooled as usual ; it is then to be alumed anjd dyed in a liquor made of Brazil wood of the common heat, then in the cold logwood liquor, and lastly, a solution of pearl-ash must be added to the liquor in which the silk is last dyed. It is after- wards to be washed and dried ; but for some shades it is best to have fresh liquor, particularly for the warm Brazil, the cold logwood, and the solution of pearl-ash : in this case the quantity of each may be much better regulated. To dye silk violet or purple ivith Brazil wood and Archil. The silk when alumed is to be dyed in the decoction of Brazil wood according to the shade required ; it is then to be washed and dyed in archil : and it is afterwards washed a second time. After this it is dipped in the blue vat, and wrung and dried with the same accuracy used in greens and blues. For dyeing silk black and some other^ colours, see Chapters V. and VI. CHAPTER IV. ON SCOURING AND DYEING WOOL. On the action of alum and tartar upon wool — A pastil or woad vat for blue — To prepare the indigo mentioned • in the preceding directions — Rules to judge of the state of the vat — Indications ivhen a vat has had too much or too little lime — To work a vat which is in proper order — On the putrefaction of the woad vat — Methods of dyeing blues — To dye wool, with lac-dye, scarlet, or crimson — To dye ivorsted yarn a ciimson — A preparation of archil to finish the crimson — On dyeing wool scarlet — To dye wool maroon — To dye wool yellow — To dye ivool brown or of a fawn colour — To dye wool purple, S^c. — To dye wool green — A chemic vat for green woollen — A chemic vat for blue ivoollen — To dye wool orange, gold colour, &)C. — To dye wool black — another process for black with- out a blue ground — To dye wool grey — Mixture of black or grey with red and blue — On browns, fawns, greys, SfC. — On the yelloiv of quercitron bark — On a full bright yellow from the same bark — Bancroft's murio-sulphate of tin — To dye wool buff- — To dye wool peach — To set an Indigo vat for worsted, sergei Wool is usually scoured for being dyed with stale urine, the staler the better ; it is used in the proportion of one ON SCOURING AND DYEING WOOL. 71 part to three parts of water, full as hot as the hands can bear when the wool is worked about in the fluid. — If the wool be in the fleece, what is called its natural yolk, and which is said to preserve the wool from the moth, is of a greasy nature, and is scoured out by the volatile alkali in the urine. If the wool be in the state of spun yarn it has gallipoli, or rape oil, in its thread, the spinner, or rather the comber, using it to render the wool more flexible, &c. It is absolutely necessary that wool, (as indeed every other material to be dyed) should be made very clean and white, if any brilliant or bright colour is to be imparted to it. For this reason it is that the wool is passed two, three^ and in some instances even four times through fresh scouring liquors ; in the last, and sometimes in that which precedes the last, soap is used in the proportion of from seven to fourteen pounds, and in some instances to twenty one pounds or more, to a pack of two hundred and forty pounds of wool, according as it is fine or coarse : for superfine colours more than common is used. Worsted requires less than coarse yarn, having less grease and dirt in it. It ought, however, to be known, that boiling vfoo\ for a long time in any alkaline liquors, or a liquor made of soap, tends greatly to the decomposition of the cloth; indeed long boiling in any strong alkaline ley converts wool into a kind of soap, and, hence, it is easy to see why such processes injure wool or cloths made with it. The preceding observations apply to the alkalies in a caustic state, or in the state of carbonate, not when they are neutralized by powerful acids: for wool, when fit to receive the dyes, and if it is designed to be dyed 72 ON DYEING WOOL. yellou', should boil two hours with one-tvvelfth or one- tenth of its weight, of sulphate of alum (common alum) observing proper precautions, and the use of a sufficient quantity of prepared weld plant boiled, &c. ; or of quer- citron bark, as will be shown in the processes of the different yellows. If it were yarn, and the threads cut in two, it would be found dyed throughout, and of a body and richness in proportion to the correct application of the various ingredients, and with due regard to time, weight, measure, &c. In the process just mentioned, w^e may observe, that the quantity of alum and of the weld plant used will be found very considerable : from one twelfth to a fourth of alum, and, according to the French method, four or five times more weld than the quantity of the wool. When a process of dyeing has been scientifically con- ducted, the wool will take so much of the alum that the bath will hardly taste of it ; and afterwards take the colour of the dye bath out of it ; so that the remaining liquor put into a glass will be nearly like water. The action of alum and tartar upon wool. From the experiments of Dr. Ure, {Notes to Ber- thollet, vol. ii. p. 323^ it appears that alum has the property of increasing the solubility of cream of tartar ; that as, in using alum and tartar, the wool is impregnated with alum and a large quantity of tai'taric acid, these two salts should never be employed together, except when the colour is susceptible of being heightened and rendered brighter by acids, as is the case with cochineal, madder, ON THE WOAD VAT FOR BLUE. 73 and kermes. On the contrary, alum should never be employed for wools intended to be dyed with woad, or Brazil-wood, the colour of which is easily destroyed or altered by acids. To conclude these preliminary observations, wool has a strong and powerful affinity for all dyeing materials ; and, therefore, the processes for dyeing wool are, in general, by no means so complicated as those for dyeing cotton, silk, 8fc. ; although some colours, even to these, are readily, and without a complication of processes, im- parted. A pastil, or woad vat for blue. Take, upon as small a scale as can conveniently be tried, a copper vessel, which will contain about twelve gallons, two thirds full of soft water, and one ounce of madder. Fix this small copper in a larger copper of water, so that the heat may be applied to keep the liquor in the smaller copper at a proper temperature ; it will be then, in fact, a water bath. Having kindled the fire in the afternoon, put in a good handful of bran and five pounds of woad ; at five o'clock in the evening let it be well stirred and covered over, the liquor being about blood- warm; let the same heat be continued as nearly as possible, at least so as not to be lower than summer heat by the thermometer, nor higher ihsM fever heat by the same instrument. The vat must again be well stirred at seven, at nine, at twelve at night, at two in the morning, and at four. E 74 ON DYEING WOOL. Hellot, describing this process, observes, that " the woad then working, some air bubbles began to rise pretty large, but few in number, and of a very faint colour; it had then two ounces of lime added, and was stirred; this was four o'clock in the morning ; at five a pattern was put in, and at six it was taken out and the vat stirred. This pattern had received some colour. At seven o'clock another pattern was put in, and at eight it was stirred again. The second pattern was tolerably bright. An ounce of prepared indigo, (see p. 75.) was then added ; at nine o'clock another pattern was put in ; at ten it was stirred again, taking the pattern out, and putting in an ounce of lime because it began to smell sweetish; at eleven another pattern ; at twelve at noon it was stirred again. This process was continued till five o'clock in the evening ; then were added three ounces of prepared indigo ; at six another pattern was tried, and at seven it was stirred again ; the last pattern came out of a very good green, and became a bright blue. One ounce of lime was added to sustain it till nine o'clock the next morning ; patterns were put in from time to time : the last was very beautiful. The vat was then filled up with water and a small quantity of bran and stirred ; after which patterns were tried every hour till five o'clock in the evening, when, being in a proper state, it was imme- diately worked. Some lime was then added to preserve it ; it was stirred and left to another opportunity to re- heat." ON THE WOAD VAT FOR BLUE. 75 To prepare the indigo mentioned in the preceding directions. Boil, in a gallon of water, for three quarters of an hour, two ounces of pot-ash, three quarters of an ounce of madder, and one ounce of bran ; then let the whole settle for half an hour. After all is settled and taken out of the boiler, and put into another copper with four ounces of indigo finely powdered, the liquor should be kept stirred, and very hot, but not be boiled. At intervals some lixivium of lime should be put into it, and that being cold will keep the liquor from boiling, and render the pot-ash more active. As soon as the indigo is dissolved and properly diluted, damp the fire and cover over the solution; after it is settled put in a pattern, which, when taken out, will turn blue on being exposed to the air ; if it does not, more clear lixivium must be added. Of this solution "of indigo such proportions are to be added to the woad vat as are directed in the preceding process. Rides to judge of the state of the woad vat. The vat is ready for working, and to dye blue, when the sediment at the bottom, on being taken out of the vat changes to a fine brown-green. When the froth which rises in great bubbles on the surface is of a fine Prussian-blue, and when the pattern which has been steeped an hour, comes out of a dark gi-ass-green, and changes in the air to a blue ; when the liquor is clear and reddish, and the drops which stick to the rake are E 2 76 ON DYEING WOOL. brown ; when the sediment changes colour on being taken out of the Hquor, and becomes brown on exposure to the open air ; when the hquor is neither harsh nor greasy to the feel, and neither smells of lime nor of ley, the vat is known to be in a proper state for working. Indications when a vat has had too much or too little lime. These extremes ought to be carefully avoided. When the lime is deficient, or a pattern comes out of a dirty grey, and the sediment does not change its colour, there is scarcely any effervescence on the vat ; the liquor smells only of lime, or of the lixivium of lime. To remedy the deficiency of lime. If the vat be not too far gone, after the addition of a little bran, madder, and some woad, then try the patterns from hour to hour ; thus you will be enabled to judge. A deficiency of lime is evident when there is no effer- vescence on the liquor; and when, by dashing about the surface of the liquor, it makes a hissing noise, and by the bursting of a number of small air bubbles, which as soon as they are formed break, and appear tarnished, and are not large, nor of a fine colour ; the liquor too has an offensive smell, like rotten eggs ; it is harsh and dry to the feel, and the sediment, as has been before observed, does not change colour when taken out of the liquor. Sometimes such a condition of the vat is absolutely irremediable ; but when not gone too far, sprinkle some ON THE WOAD VAT FOR BLUE. 77 lime into the liquor, and stir it. If you can thus remedy the defect, and bring the liquor to smell of lime, and to feel soft, cover the vat, and let it stand. If, at the expi- ration of an hour and a half, the effervescence begin, you may put in a pattern ; in an hour afterwards, it may be taken out, and regulate your process by the degree of green which the pattern has imbibed ; but, in general, when vats are thus out of order, they are not so soon re- covered. To work a vat which is in proper order. The vat being in a proper state, the cross suspended, and thirty ells of cloth ready, or scoured wool in propor- tion, designed for black, by dyeing it of a blue grey ; and having passed and repassed the cloth through the liquor for a full half-hour, it is to be wound round the winch, and throv/n off into the barrow, and aired by the listings to change the green to blue. After this, a second piece may be dyed by the same process. Having made this overture, or Jirst stirring, as it is also called, the vat must be stirred afresh, adding lime ; but not so much as to desti'oy the proper smell and feel. If the vat be in a good state, on the first day, it may be stirred three or four times ; but it must not be over- worked, particularly on the second day. Co7icerning the colours to be obtaiiiecl to the best pos- sible advantage from afresh vat on the first day, — the first is for black, the next for royal blue, and the third a brotvn green. On the second day, violet, purple, and Turkey blues in the last stirring. On the third day, if the liquor be too much diminished, it must be filled up e3 tb ON DYEING WOOL. with hot water. At the end of the week, lig/it blues may be done, and on Saturday night add rather more hrae, to preserve the vat till Monday morning. On Monday morning add more indigo, and stir the paste ; keep the vat liquor at a proper distance from the top. Cover it for two hours ; then put in a pattern, and in an hour take it out ; add lime according to the green shade of the pattern, and in an hour or two, if your vat has not suf- fered, you may begin working it afresh. To keep the cloth, &c. from the sediment, there is always let down into the vat, before the work is begun, an iron circle, with cords fastened from the circumference to the centre. On the putrefaction of the woad vat. Whatever be the cause, most certain it is, that the woad vat, even when prepared in the most careful and scientific manner, is soon disposed, if not used, to go into the putrid fermentation ; of this we may be satisfied, when it smells like rotten eggs, as stated above. The loss of a woad vat to dyers is extremely serious, both from the quantity of woad, as well as of indigo, which it contains : these articles being always expensive. The woad vat being worked by heat directly applied from an open fire, (the old method of heating it,) was much more liable to be lost than if it remained cold, or was worked contimialhj, as it usually now is in London; added to which, the more equable application of heat by steam, there is not now the danger which there was in cessation, at uncertain times, and in uncertain states of the vat, as to richness or poorness of woad or of indigo. ON THE WOAD VAT FOR BLUE. 79 But a dyer in the country, whose business is barely sufficient to keep a vat going, will find more difficulty in this respect. If, therefore, he does a small batch of work on Monday, but has not half worked down his vat, and has no prospect for two or three days of doing any more work, he may possibly try to keep it with lime for a day or two : he may do so, and in the issue, in some in- stances, too much lime is the consequence. We consider, however, that when the vat can be worked daily, and replenished as it is worked down, as is the case in Lon- don, with care and attention, there is no danger of the loss of a woad vat: in London, such an accident now seldom happens. The author is, notwithstanding, per- suaded that all the art of man cannot always keep a vat from the state of having either too much or too little lime, when heated but seldom, under a short course of work : for when a vat is in order, it is like a ripe vege- table ; you must gather it, or it passes the time of its perfection ; it may even be rotten ripe. We say, there- fore, WORK THE vat: withdraw from it, upon your cloth, its colour, which, as soon as you expose it to the atmosphere, will combine with its oxygen, — the oxygen with the carbon of the indigo and the woad. If you play with it too long, the putrid fermentation will begin, and the vat will be spoiled. The smell of rotten eggs always proclaims the approach of the mischief. No one, therefore, should attempt to have a woad vat or vats, unless he can keep them nearly always at work. When worked down in a moderate time, and replenished with lime, woad, indigo, &c., working out and replenish- ing in, there can be no danger. On the other hand, in E 4 so ON DYEING WOOL. proportion as the vat is out of condition, although par- tially recovered, it must always be with more or less loss. Methods of dyeing blues. Whether the goods be cloth, or skeins of yarn, ihey must, in all cases, be first wetted out and wrung, and then put into the vat, worked in it, taken out and aired, that they may turn from green to blue ; and, if necessary, they must be put in again. There is no difficulty in dyeing darJc blues, by repeated dippings ; but if UgJd blues be dyed in vats which are nearly exhausted, they will not be bright. Blue vats, upon a large scale, are now mostly heated by steam ; they are then, with little trouble, always in a state for working, without the necessity of re-heating. They are very convenient for light colours, even after they become very weak. In some instances, in order to dye light colours to the best advantage, it would be advisable to set a vat on purpose, which should be strong in woad and weak in indigo ; because the colour would be given more slowly, and the light colour obtained from them with much more facility. To dye wool with lac-dye, scarlet and crimson. We have mentioned lac-lake and lac-dye in page 12. Lac-lake is of very uncertain quality, having many hete- rogeneous substances mixed with it.' Lac-dye is very superior to lac-lake. Lac-dye is much used for dyeing woollen yarn scarlet -and crimson, for carpets and hearth- ON DYEING WOOL SCARLET AND CRIMSON. 81 rugs. It is used with a peculiar spirit, which may be purchased of the dry-salters. Some think that this colouring material is nearly equal to cochineal ; the au- thor has, however, never seen any thing dyed with it equal to the colour obtained from cochineal, although it affords, nevertheless, a good scarlet. Lac-dye is used by being powdered and put into a stone pan, (the quantity must be in proportion to what is likely to be used), with a portion of the above-named lac-spirit sufficient to make it about as fluid as treacle ; it must be stirred with a glass-rod or a tobacco-pipe. Some use alum and tartar as a preparation, and some not. After putting the mixture of lac -lake and spirit in the copper with a proper quantity of water, add the goods and work them at a boiling heat. For scarlet add quer- citron bark, for crimson, archil. Lac-dye may be, however, prepared for dyeing, by submitting it, in powder, in a leaden vessel, to the action of sulphuric acid, in the proportion of not more than one part to two of the dye; and after the lac-dye is dissolved, the acid may be neutralized by carbonate of soda. With suitable mordants to the cloth or yarn, the colour may be then applied. Other processes for the employment of this dye are also adopted, but we have no room to detail them. (See Ure's Notes on Berthollet.) To dye worsted yarn a crimson. Proportion of wool, one pound ; of alum, two ounces and a half; of white tartar in powder, one ounce and a half. Having the water properly cleared by bran, let the E 5 82 ON DYEING WOOL. alum and tartar be boiled in it ; when it begins to boil, stir the mixture well, and put in the worsted, which boil in the liquor for two hours ; then prepare a fresh liquor for the cochineal, one ounce of which, in powder, is to be used for every pound of wool ; when it begins to boil, stir it well, put in the worsted, and boil it till the liquor in the vessel is free from colour, it having parted with the colouring matter of the cochineal, which should now all be upon the worsted. If a series of shades be re- quired, less quantities of cochineal, alum, and tartar, must be used ; the lightest shade is dyed first. The preparation of archil to finish the crimson. Put as much archil as the goods may require, and ac- cording to the deepness or lightness of the shades of the crimson required, into a copper of water of a suitable size, and boil it, (the best canary archil will bear boiling) ; damp the fire, let the archil settle, and then have a fresh liquor for the goods to be put in, to receive a proportion of archil according to the pattern desired to be matched. Begin with the lightest and end with the deepest, reserv- ing the remains of the archil liquor, if it be not all spent, for common compound colours of such shades as it will be advantageous to use it in. (See the next article.) On dyeing wool scarlet. Scarlet owes its beauty to a solution of tin in muriatic acid. For this purpose some use muriate of ammonia, commonly called sal-ammoniac, others use common salt. ON DYEING WOOL SCARLET. 83 It is of little consequence whether common salt or sal- ammoniac be used : different preparations are employed by different persons. The author has found the follow- ing to answer every expectation. Melt an ounce of grain tin in an iron ladle, till an oxide is formed on the surface ; then pour it from a height or distance into cold water. Pour the water from it, and it is fit for use, being then Cd^e& feathered tin. Put this tin into a glass vessel or stone jar, and add to it eight ounces of nitric acid, eight ounces of water, half an ounce of sal-ammoniac, and two drachms of nitrate of potash. This preparation is better if made some time before it is used ; it is a compound of nitrate and muriate of tin. Should any one prefer a pure muriate of tin, the me- thod of making it will be found in the last chapter, in ob- servations on crimson and scarlet upon silk. Into a copper of cleared boiling water, the heat being reduced, and having the worsted wetted out ready ; for every pound of which (dry) put two ounces of cream of tartar or ivJiite tartar in powder, and one drachm and a }\a[{ oi cochineal in powder. When the liquor is ready to boil, add two ounces and a half of the first-mentioned solution of tin, which immediately changes the colour ; stir it well : as"soon as the liquor boils put in the worsted, and boil it till the colour of the cochineal is taken up by it. The worsted must now be taken out, when it will be of a flesh-colour, the water in the copper having lost its colouring matter. To finish the worsted, another quantity of clean water is made warm, into which six drachms and a half of cochineal are to be put ; just before it boils, two ounces of the same solution of tin are to be E 6 84 ON DYEING WOOL. poured in, the liquor undergoing a similar change as before. The worsted is again put in, and boiled till it has imbibed the colour ; it is then taken out, \n'ung, and rinsed in clean water, when the scarlet is in perfection. One ounce of cochineal to a pound of wool, will im- part a colour sufficiently deep, if managed according to the method above described, no colour being left in the remaining liquor. For many shades of scarlet it will be, however, neces- sary, and, in a fresh liqucr, to add either a certain portion of turmeric or young fustic, to give the scarlet that fiery red which some scarlets have. If not in an entire fresh liquor, a part of the old liquor must be taken out before the yellow is added. When it is wished to dye a regular series of scarlet shades in worsted, half the quantity or less, for some of the lightest, will be sufficient of the solution of tin, the tartar, the cochineal, &c. The worsted should be sepa- rated into divisions corresponding with the shades re- quired ; the lightest is of course to be done first : if any deficiency be in the shade, it may have another chp. This deficiency is easily perceived, and a very little practice will enable the operator to assort them perfectly. It should he noted, that the vessel most proper to dye scarlet in ought to be made of block tin ; such as are used by the scarlet dyers for the East India Company. When woollen cloth is to be dyed scai'let, to every hundred pounds of cloth put six pounds of tartar and eighteen pounds of the solution of tin at first ; the same quantity in the completion ; and in each operation, six pounds and a quarter of cochineal. ON DYEING WOOL MAROON. 85 For the accommodation of those who would make small experiments, one ounce of cream of tartar, six ounces of solution of tin, and one ounce of cochineal, may be used for every pound of worsted or cloth, putting two-thirds of the solution of tin and the tartar, and a quarter of the cochineal, into the preparation, and the remainder to the completion. Observe, that although we have given processes for dyeing woollen cloth crimson as well as scarlet, yet crim- son may be obtained in another way : for alum, the salts in general with an earthy base, and the fixed and volatile alkalies, possess the property of changing the colour of scarlet into crimson, the natural colour of the cochineal. The cloth which is dyed scarlet has only to be boiled, therefore, for about an hour, in a solution, more or less charged with alum, according as a deeper or lighter crim- son is wanted. When a piece of scarlet has any defects, it is set apart for crimson. Soap and potash will also produce crimson from scarlet, but not of so bright a colour as from alum. Hence also we learn the necessity, in, at any time, working scarlet cloth, to avoid boiling it with soap or pot-ash, &c. if we desire the scarlet to remain. To dye wool maroon. The worsted or yarn must be boiled for an hour or two in one twelfth its weight of alum and the same quan- tity of white argol. It is best, when there is a large quan- tity of yarn, to do this on the preceding day : if your copper hold a pack of two hundred and forty pounds, it 86 ON DYEING WOOL. will be cold enough to handle after remaining with the fire out during the night. When the skeins, &c. are taken out and arranged upon poles or sticks, have a fresh water ready in the copper, into which put about thirty pounds of chipped peach- wood, and when it has boiled half an hour, pour in some water to cool it down, and add fifteen pounds of crop madder ; work the yarn in this liquor rather under a boiling heat. When it is full enough, for some shades you must add archil. As the whole pack is dyed at four or five turnings in, some of the pai'cels may be varied in the hues instead of confining them all to one shade. The various turnings will take the greater part of the day to perform. When you choose to have as many shades as there are turnings in, you divide the drugs into different portions for different periods of the time, to be used ac- cording to the patterns required. The most economical method of using the drugs being to follow the patterns one after the other : practice will teach the operator to do this most advantageously. More madder than peach-wood gives a lively red; more peach-wood than madder gives a bright maroon red, bordering on crimson, but more so without any madder ; with the addition of archil it gives a crimson, but by no means to be compared with the crimson of cochineal. Urine with the archil renders a less quantity of archil necessary. ON DYEING WOOL YELLOW. 87 To dye wool yellow. The proportion of alum used by dyers in these pro- cesses varies from one-fourth down to one-twelfth, of tartar one-sixteenth is used, for every pound of cloth. Equal parts of alum and tartar are used for worsted and yarn, each of which (alum and tartar) is only from one- twelfth to one-tenth of the weight of the material to be dyed. The shades of yellow are straw yellow, pale yellow, lemon yellow, a.nd J'ull yellow. In order that the cloth should be properly impregnated with the mordants of alum and tartar, according to what is allotted to the shade, whether light or full, it should be boiled in the preparation at least one hour ; two hours for a full yellow ; then a fresh liquor is to be made to receive the weld, which must be previously boiled : for a full yellow four or five pounds of weld will be required to one pound of cloth or worsted ; for the lighter shades less of course: but a sufficient quantity only of weld should be used, and this should be boiled and re-boiled, as it will keep but a very little time after boiling. If you have a gradation of shades you will save drugs and expense by dyeing the fiillest shades first, and the lightest last ; but by this method the lightest will not be so bright as if they were done first, and the liquor renewed with fresh boiled weld, and so on to the fullest shade. At last you must have for the goods a preparation weak or strong according to the light or full colour of which they are to be. The last dyeing, whether of cloth or yarn, will as- 88 ON DYEING WOOL. suredly take all the colour out of the liquor of any con- sequence. While expense is not an object, it is best, not only for yellows, but for all other colours, to have the preparation and the dye proportioned to the shade, the colour done at once, and the remaining liquor thrown away ; but as the price usually paid for dyeing will not enable the dyer so to do, he commonly dyes his shades in succession, as above, and with the utmost economy. To dye wool brown, or of a fawn colour. These shades are extremely various, and are dyed without any preparation with alder-bark, red sanders, sumach, galls, madder, &c. and under a boiling heat, al- though it is occasionally necessary to boil some of the in- gi'edients together previous to the dyeing : for instance, red sanders will give its colour out best when boiled with galls, alder-bark, sumach, &c. Cam-wood, bar-wood, walnut rinds, roots, &c. are used in some of these shades, the varieties of which are almost infinite. Practice is required in this branch of dyeing equal to or beyond any other. To dye wool purple, 8fC. Pass the goods through archil, next through the blue vat, with the usual precautions, then through hot water. For some shades they should be alumed, and then dyed with cochineal for the crimson part of the purple. Bltie and crimso7i make purple, violet, &c. according to the patterns required. ON DYEING WOOL GREEN. 89 To dye wool green. The shades of this colour are very numerous, as yellow green, ^mle green, bright green, grass green, laurel green, olive green, sea green, parrot green, cabbage green, ducJiS-wing green, &c. The goods must first have a blue ground from the woad vat, light or full according to the pattern, they are after- wards to be prepared with alum and tartar, weak or strong according to the lightness or fulness of the pat- tern, and are afterwards dyed in weld liquor. Many of the shades of green are more readily done by dyeing the wool first yellow with old fustic, with a preparation of alum and tartar, and using the chemic blue vat made with sulphuric acid and indigo. See page 47. A chemic vat for green woollen. Prepare in the manner described for cotton, (page 52.) eight ounces of indigo and four pounds of sulphuric acid. This preparation need not, however, be neutralized for wool as described for cotton. In some instances the preparation is to be for the yellow of fustic one-twelfth of alum, the same quantity of tartar, and in some cases one-twelfth of alum only. A chemic vat for blue woollen. This is to be made the same as for green ; it need not be neutralized as for cotton. For blue, however, twelve ounces of indigo are necessary to four pounds of sul- 90 ON DYEING WOOL. phuric acid. In dyeing the heat must be much under boiling, or the using of a high heat would give the blue a green tinge. This blue colour is very bright, yet not fast, but no preparation is of any advantage to either its fastness or brightness. Some put alum and tartar, and some use one, and some the other, to prevent a green cast : if, however, the wool be fine, white, and worked much helow the boiling point of heat, it will not turn green although neither be used. To dye wool orange, gold colour, S^c. The processes of crimson, scarlet, and of yellow united produce the various shades of these colours, having archil out. See huff, peach, Sj-c. o?i wool. To dye wool black. Black includes a prodigious number of shades, begin- ning from the lightest grey or pearl colour to the most intense shade of black. On account of these shades it is classed by dyers among their chief or primitive colours * ; for the greater number of browns, of whatsoever shade they be, are finished in the same dye as would dye white wool a grey more or less dark. This operation is called browning. The best superfine black should have a full ground of mazarine blue previously to being finished black. * It is necessary that the student should not confound the terms ;3rj;n»7ij;e colours liere with the prismatic or primary colours, for the discovery of which we are indebted to Sir Isaac Newton. See the Introductory Chapter, ON DYEING WOOL BLACK. 91 A great quantity of cloth and other articles have, how- ever, no indigo ground, but a ground of logwood, or of logwood and alder-bark, or of logwood and old fustic, or of logwood, alder-bark, and old fustic, all boiled to- gether, and sometimes they are boiled in a decoction of oak saw-dust. Indigo for the ground is the richest drug, in carbon, that is or can be used ; logwood is next to it : too much logwood, however, whether indigo be used with it or not, gives the black a foxy hue ; alder-bark and old fustic modify this effect, and are used in small quantities for this purpose, because the dye from these, as well as that from oak saw-dust, will produce a soot or dead black. A jet black is required full and rich, therefore old fustic and oak saw-dust are only used to modify the rich- ness of the ground as it regards the blue, whether of in- digo or of logwood; for logwood especially, without these, if overcome with sumach and sulphate of iron only, would be foxy, purplish, or have a reddish cast. So many different grounds being used for blacks, and every dyer thinking his own the best, is the occasion o^ such a great variety of hues, even of black, being found in the market. It is, therefore, thought unnecessary to describe the various methods of dyeing black which are pursued by different dyers, and which would be, in fact, impossible. But the author has done what is of much greater importance to the student, who, after a little prac- tice, let him have a pattern of black to dye, will know how to do it, let who may have dyed it. Even a blue-ground is, according to some, dyed after- 13 92 ON DYEING WOOL. wards in a decoction of logwood and galls, or logwood and sumach, and two pounds of verdigris for a hundred pounds of cloth. Thus, ten pounds of logwood and ten of galls, are to form the decoction, and are boiled pre- viously for tw^elve hours. One third of it with the verdi- gris is used first, and then the cloth, after boiling in it for two hours, is aired ; it is then passed through one third more of the decoction of logwood and galls, having previously had eight pounds of sulphate of iron dissolved in it, and the scum arising from the solution taken off. The goods are to be worked in this one hour at a boiling heat, then aired again by turning them about on a stone floor. The remainder of the dedoction of logwood and galls is then added, with fifteen or twenty pounds of sumach ; boil it some time, and then add five pounds of sulphate of iron ; scum it, and let the liquor cool down, then put the goods in, and work them at a boiling heat an hour or two, taking them out once or twice, at least, in the time, to air and cool ; they are then to be well washed, and passed through a decoction of weld liquor, to soften the black, which will be very fine. This pro- cess is chiefly from HcUot ; but the quantity of sulphate of iron is more by three pounds than he directs. When the cloth is blue, it is usually boiled two hours in a decoction of galls, then washed and aired, when sul- phate of iron and logwood are added to the liquor, and the goods worked in it for two hours, and then washed. The above have been the processes in practice for a century past in France, where the galls were not so dear as they now are in England : sumach is here, therefore, now most commonly used as a substitute for galls. ON DYEING WOOL BLACK. 93 Another process for black without a blue ground. To dye one hundred weight of cloth, take thirty pounds of chipped logwood, half a bushel of alder-bark, and six pounds of sumach, and boil them together in a proper quantity of water for half an hour ; then cool the decoc- tion down with cold water, enter the cloth, turning it on the winch ; bring it to a boil, having the sumach in a bag ; boil and keep the cloth turning for one hour and a half: this is the ground. Have now ready fourteen pounds of sulphate of iron dissolved in water, which is to be laded into the copper by one man, while another turns the cloth for an hour at a boiling heat; it is then to be taken out, cooled, and aired, returned to the copper, and boiled gently for two hours, and then cooled again, "While the cloth is cooling, six pounds of logwood, ten pounds of alder-bark, two pounds of argol, ten of soda, or common pot-ashes, and three pounds of sulphate of iron, are to be added to the liquor in the copper, and boiled one hour, when the goods must be turned and worked one hour ; and, lastly, taken out and aired. This black is said to be of the hue of a raven's feather. This process is from Heigh. The argol is professed to be put in to counteract the sulphuric acid of the sulphate of iron ; the alkali is said to cause the logwood to retain its natural violet colour : and if too great a quantity of logwood be not used, the result would be as above stated. But the author pre- sumes that such a black would not be at this time much esteemed. We object to the intrdduction of so much, 94 ON DYEING WOOL. indeed of any alkali or argol, as the time employed in performing the process is wasted. Alkali is good, how- ever, where a chemic green is to be dyed black. Wool will take up whatever the copper contains neces- sary to dye black ; but, for the beauty of the colour and the durability of the cloth, it is best to let it have most of its ground of vegetable colour before it has the sulphate of iron, which blackens that ground, with sumach instead of galls ; and even in some instances, dyeing some goods without the sumach. Were the author, however, to direct the dyeing of black cloth, such as should be of the best kind, he would have an indigo ground with logwood and alder-bark, without old fustic or oak saw-dust; and to finish the cloth he would use sumach, sulphate of iron, and a small quan- tity of verdigris. He ivould give it the blue ground first; then the logwood, alder-bark, a?id verdigris ; and then finish it with sumach and sulphate of iron. If the blue ground were omitted, he should dye the cloth twice, giving it more of logwood and alder-bark, but verdigris the same ; and finish it with sumach and sulphate of iron. Nevertheless, when we dye to a pat- tern, the pattern must be our guide. Different goods will require different quantities of drugs. Logwood should be about one-fourth of the weight of the goods ; the sulphate of iron about one- fifth of the logwood ; alder-bark, when used, about the same quantity as sulphate of iron ; but for some yarns this bark is not used, nor is it necessary ; and where fustic or oak saw-dust is used, there is the less necessity for using alder-bark. The sumach must be about the ON DYEING WOOL BLACK. 95, same quantity as sulphate of iron. Remember that carbon is generally considered as that which makes the richness of a dye. That it is the iron in the sulj^hate of iron, combined with the tannin and gallic acid which are as- sumed to be in the sumach and logwood, that produces the blackness of the dye ; but this theory is questionable. See beloiv. The way to ascertain when the quantities of drugs are most appropriate for producing the desired effect is as follows : — First, ground with different quantities of drugs, from three to five or seven patterns, and use from one third to one fifth of sulphate of iron and sumach to the ground- ing ; afterwards finish with the remainder of the sulphate of iron and sumach : the fuller the ground the richer will be the black, if the logwood be not in excess, and the quantities be used as thus stated. We ought also to state here (from Berthollet, Vol. ii. p. 4.) that commonly more simple processes than any of those above described are employed for black. Thus the blue cloth is simply turned through a bath of gall- nuts, when it is boiled for two hours. It is next passed through a bath of logwood and sulphate of iron for two hours without boiling, after which it is washed and fulled. A black may also be dyed without a blue ground w'ith walnut rinds or the roots of the walnut tree ; in this case the cloth receives a dun ground from the walnut husks or roots, and is afterwards made black in the manner above described, with logwood and sulphate of iron. 96 ON DYEING WOOL. The blacks, however, withoid the blue ground are only given in general to inferior cloths. The colouring princijjle of logwood is called hematin; it is crystalline, of a rosy-white, and, viewed through a lens, very brilliant ; its taste is slightly astringent, bitter and acrid; exposed to the action of fire in a retort it affords all the products of animal substances, and also a small quantity of ammonia, which proves that it contains nitrogen. It dissolves easily in boiling water ; on adding some acid very gradually, it changes to yellow and then red. Potash and ammonia give the solution of hematin a purple red ; if a great excess of these alkalies be added, the colour becomes violet-blue, then brown-red, and finally yellow-brown. In this state it is decomposed and cannot be recovered by any acids. Protoxide of lead, protoxide of tin, hydrate of tritoxide of iron, hydrate of copper, oxide of zinc and its hydrate, flowers of antimony and oxide of bismuth combine with hematin and give it a blue colour, with the loss of the violet shade. See notes to Ures Berthollet, Vol. ii. p. 420. See the ex- planation oi protoxide, &c. under oxide in Chapter I. The above facts concerning logwood may, by the in- genious dyer, be applied on many occasions with great success. To dye wool grey. All greys, from the darkest to the lightest, are com- posed of black in varying proportions. They are of gi-eat use in dyeing, not only for their own colours, but ON DYEING WOOL BROWN. 97 also when applied to other colours, which operation is called saddejiing or darkening. Some greys have a woad ground of blue, then of log- wood, sumach or sulphate of iron, of which decoctions of the three last, for expedition, should be in readiness when wanted. When a succession of light shades, in particular, is required, in some instances the chemic blue is used : when we treat of the mixture of black, or rather grey with red and blue, the utility of grey will be seen. Mixture of black or grey with red and blue. These produce an mfinite number of all shades of grey as sage grey, slate and lead colour, and others still darker. On BROWNS, FAWNS, OLIVES, ^C. Browns and Faivns owe, in all probability, their colour to the iron which their dyes contain. Iron is so uni- versally diffused throughout nature, that it, very likely, enters into the composition of many other colours ; it exists in blood, in water, and in innumerable vegetable and animal substances, as well as in earths and many minerals. Hence we ought not to be surprised that blue, red, a.nd fawn produce olives from the darkest to the lightest ; as well as slate and lavender when the shade is very light. Fawn and yellow produce the feuille-morte or dead- leaf. Fawn and red produce cinnamon, tobacco, chest- nut, 8fc. F yS ON DYEING WOOL. Fawn and black produce coffee, maroon, ^c. Blue, yelloiv, and black produce all the dark greens, even to black. Blue, fawn, and black produce dark olives and greenish grei/s. Bed, yellow, axidifawn produce orange, gold colour, withered-leaf, carnation, burnt cinnamon and tobacco colours of all kinds. Yellows, fawn, and black produce hair colour, nut" brown, ^^c. This enumeration is meant only to give a general idea of the ingredients proper for the production of shades composed of several colours. Where red forms a component part of the colour wanted, the goods must have a preparation of alum and argol, strong or weak, according to the fulness or weak- ness of the red which forms a part of the compound dye, such as the half or quarter of the quantity which is re- quired for a full colour of red ; the same as to yellow, and, in proportion, when red and yellow are joined. On the YELLOW of the Quercitron or American bark. The querciti'on bark is said to yield from eight to ten times more colour than weld, and about four times more than old fustic ; this was, however, Dr. Bancroft's ac- count, who had a strong interest in this dyeing drug, as stated in the first chapter. He also asserts, that one pound of bark with muriate of tin, will dye forty pounds of woollen a bright golden yellow, which afterwards be- comes a beautiful and durable scarlet, with a fourth part less cochineal than is usually employed on other occa- sions for such a colour. But Bancroft did not succeed in ON DYEING WOOL YELLOW. 99 doing away the old method of saving tartar and cochi- neal. His fullest yellow upon cloth, the author has, however, often tried and found it rich and golden ; the process is as follows : Cloth one hundred pounds ; bark in powder, and in a bag, ten pounds ; muriate of tin, or rimrio- 13 Chloride of lime 38 Cochineal 9 Colours, on fast and fugitive... 39 for dyeing 6 Sir I. Newton's primary 18 to prove 41 Composition for dyeing silk scarlet 141 Combustion 28 Copper 10 154 INDEX. PAGE Copper, acetate of 10 sulphate of ib. Coquelicot, to dye silk 138 Cotton, on dyeing 47, 104, 123 to dye chemic or Saxon blue 47 black 108,110,114 ■ green.. 52 — ^— a fast green ... 56 buff 58 green with in- digo and weld 56 pink 60 violet 115 duck's - wing green or olive 128 brown, maroon, &e. ib. red 116, 117 yellow by chro- mate of lead 151 , skein, to dye, yellow. . 124 furniture, to dye, yellow ib. — the same to re-dye 127 Cream of Tartar 9 Crimson, to dye, by archil on wool 80 ■ lac dye on wool ib. •^-^^———— worsted yarn 81 onsUk 140 Cudbear 8 Decoction, what 53 Distilled verdigris 17 Drugs used in dyeing ^ Dye-houses 42 Dyer, the trade of a 1 Dyers of Adrianople red. .... , 2 black 3 grain 1 silk, skein 3 rag ib. woad 2 woollen 1 worsted yam 3 weed , 17 Fawn, to dye wool 88 Feathered tin 83 Fermentation, the \-inous .... 25 —————— ^ acetous .... ib. PAGE Fermentation, the putrid .... 25 Fibrin 24 Gall of animals 10 Galls ib. Gallic acid ib. Gas, what 31 Gelatine 24 Gold colour, to dye wool 90 Green, to dye the chemic, on cotton 52 cotton a fast ... 56 ■ ' ■ wool 89 woollen ib. cotton duck's- wing 128 silk 145 vitriol, or copperas. ... 12 Grey, to dye wool 96 on silk 1 47 Hematin 96 Hydrogen 29 carburetted ....... 32 sulphuretted 33 Indigo •••!> 10 prepared 75 sulphate of 11, 51 neutraUzation of 52 Indigo, solution of, for penciling muslin 57 vats 54. 102 Inflammable air 29 Iron 12 acetate ib. liquor 112 muriate 12 • oxide ib. sulphate ib. Iron-moulds 34 Jennings's Cyclopaedia ....... 4 Lac dye 12 Lake ib. bow used for scarlet. . 80 Light, decomposition of 18 Lime 23 Linen, to dye, scarlet 122 blue 57 INDEX. 155 PAGE Litmus, or lacmus 8 Lilac, to dye silk 68 -^ muslin • • . • ib. Logwood < 96 M'Kernan on dyeing silk...,. 4 Maroon, to dye wool 85 cotton 128 Moidore, to dye silk 137 Mordant, what 27 the calico printers', for yellow and red 36 Muriate of soda 12 tin 144 Murio- sulphate of tin 101 Muriatic acid 12 gas 14 Muslin, to dye, lilac 68 Nitre 12 Nitric acid ib. Nitro-muriatic acid 13 Nitrogen , 23 gas 29 Oil of vitriol 15 Orange, to dye wool 90 silk 137 Orpiment 13 Oxides, what 14 Oxidation . 28 Oxygen ib. Oxymuriatic acid 13 Oxymuriate of lime . 38 Pastel 17 vat 73 Peach, to dye wool. 101 Pearl-ash 14 Phcenicin 11 Pink, to dye cotton 60 Poppy, to dye silk 138 Potash 14 Potassium 29 Prickly pear 9 Proximate constituents of ani- mals 23 ' vege- tables 21 Purple, to dye silk 67 wool 88 Pyrolignous acid 33 Quercitron bark 15 Realgar 13 Red, to dye cotton 116 PAGE Red, to dye cotton, Adrianople or Turkey ••• 117 Safflower 15 Salt, common 12 Saddening, what Ill Scarlet, to dye, with lac dye. .. 80 silk 141 ————— wool ........ 82 ^— on linen 122 Silk, on dyeing 62, 105, 123 un-gumming and boil- ing 129 -^— — whitening 132 I aluming 63, 134 — — to dye blue. 64, 67 • violet, royal pur- ple, &c 67 lilac 68 another process for the same ib. violet and purple, ib. another process for the same 69 another process for the same ib. ■ purple ib. aurora, orange, and moidore gold colour and cha- mois .« 136 black 105, 106, 107, 112 orange or aurora. . 137 moidore ib. orange 138 poppy o'' coquelicot ib. a cheap poppy. . . 139 a fine crimson or scarlet 140 ' another process for the same 142 a fine violet • • • • 143 green - 145 olive 146 grey 147 with Prussian blue 149 yellow, by chro- mate of lead 151 Silk skein, to dye, yellow • • • • 135 Soap • •• • • 31 Soda ••• 15 Sodium 30 Spirit of salts 12 wine 25 156 INDEX. PAGE Spirit of hartshorn 24 Substantive colours 27 Sulphate of alum and potash- • 7 copper 10 indigo 51 ' to neutralize 52 iron 12 ...15. 32 13 .... 15 PAGE Sulphur Sulphuret of arsenic • • Sulphuric acid Sumach 16 Tannin 10 Tar-iron liquor 114 Tartar 8 Tin 16 muriate of 1 44 niurio-sulphate of 101 — nitro-muriate of 83 Turkey red- Turmeric- . • Ultimate constituents of animals vegetables Ure's Berthollet Chemical Dictionary - • • . Utensils, on the, used in dye- ing •-• Vat, the blue indigo, for silk . • another for the same • • • • ^-^ cold indigo, for cotton • . blue, for Unen and 117 16 23 21 4 4 43 64 67 64 57 cotton ....- indigo, for worsted and serge 102 Vegetable substances, analysis of 18 Verdigris, common 16 distilled ib. Violet, to dye cotton 115 a fine, on silk . . 143 Water proper for dyeing 42 Weld 17-41 —— to dye cotton green with, and indigo 56 wool green with, and woad • 89 White, the numerous shades of, in silk" . . • Whitening silk, process for- - • • Woad , vat, rules to judge of- - how to work « « • • errors in, how to on the putrefaction of the •--. Wool, on scouring and dyeing the action of tartar and alum on to dye, orange, gold co- lour, &c. ....•• black 90. 93 blue, by the woad vat tbods blue, several me- 80. scarlet and crim- son 80, 81, maroon yellow 87. brown and fawn 132 ib. 17 75 77 76 78 70 72 90 ,94 73 89 82 85 99 colour — purple green black - another process - - greys brown, fawn, and many other colours - Wool, to dye, buff — — - peach Woollen, a chemic vat for green blue Worsted yarn, to dye, a crimson and serge, indigo vat for Yellow from Quercitron bark . • chromate of lead. • weld 87, , on, wool cotton 124, silk 135, ib. 89 90 93 96 97 101 ib. 89 ib. 81 102 98 151 125 87 151 151 THR END. Printed by R. Gilbert, St. John's-Square, London.