FRANKLIN INSTITUTE LIBRARY 
 
 PHILADELPHIA 
 
 Class, HZ . Book. Acccssion..iS?..0..<i^../..... 
 
 FcLz 
 
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THE 
 
 MGATIVE Am PRINT; 
 
 OB, 
 
 The Photographer's Guide, 
 
 c 
 
 IN THE 
 
 G- A. L IL. K R Y A.]NrD IN THE miKLD, 
 
 BEING A 
 
 TEXT-BOOK FOR THE OPERATOR AND AMATEUR, 
 
 Containing Brief and Concise Instructions for the Preparation of tlie Differ- 
 ent Kinds of Photographs now in Vogue. 
 
 6UCH AS THE 
 
 Ordinary Negative for Contact Printing, the Solar Negative 
 and the Negative for the Copying Camera; Printing on ' 
 Albumen Paper; Vignette Printing; Printing Posi- 
 tives on Opal or Plain Glass ; the Ambrotype, Fer- 
 rotype, Melainotype, etc. ; Stereographic Print- 
 ing ; the Dry Process ; the Construction of 
 the Glass-House ; the Camera and the 
 Lens ; and the Treatment of the 
 Gold and Silver Residues. 
 
 BT 
 
 JOHIV TOWLER,, M.n., 
 
 Professor of Chemistry, Natural Philosophy, and Mathematics in Hobart 
 College; Author of "The Silver Sunbeam," "The 
 Porcelain Picture," Etc. 
 
 Second Edition. 
 
 NEW-YORK : 
 Joseph H. Ladd, Publisher. No. 36 Cedar Stbbkt 
 1870. 
 
 London: TRt}BNiiE & Co. 
 
Entered, according to Act of Congress, in the year 1866, by 
 
 JOSEPH H. LADD, 
 
 In the Clerk's OfiSce or the District Court of the United States for the 
 Southern District of New- York. 
 
OOETETsTTS. 
 
 CHAPTER I. 
 
 Preparation of the Glass Plate for the Reception of the Col- 
 lodion Film — Solutions for Cleaning Glass Plates — Chro- 
 mic Acid Bath — Albumen in Stock Solution, and Diluted 
 for the Substratum — To Albumenize the cleaned Plates, 18 
 
 CHAPTER II. 
 Preparation of the Collodion, and the Mode of Coating Albu- 
 menized Plates with Collodion — To Prepare Pyroxyline 
 by the two Methods — Preparation of Plain Collodion — 
 Preparation of Bromo-Iodized Collodion — Preparation of 
 Iodized Collodion — Vials for Collodion — Pneumatic 
 Holders, . . .1(1 
 
 CHAPTER III. 
 The Nitrate of Silver Bath, its Preparation, Troubles, and 
 Renovation — Neutralizing the Bath with Carbonate of 
 Soda ; with Oxide of Silver — Boiling the Bath — Distilling 
 oft the Ether and Alcohol — Decomposition of the Nitrate 
 of Silver in an Old Bath, 29 
 
 CHAPTER IV. 
 The Sky-Light, Side-Light, Screens, and Accessories for Po- 
 sing the Model — Theoretic Views about Lighting — Practi- 
 cal Construction of a Photographic Glass-House, . . 38 
 
 CHAPTER V. 
 
 Lenses and Cameras — The Use of Stops or Diaphragms — 
 Spherical Aberration ; Chromatic Aberration — their Cor- 
 rections — Foreign Lenses — American Lenses — To Make 
 the Actinic Focus and the Luminous Focus Coincident — 
 To Focus, 47 
 
 3C G I 
 
X 
 
 CONTENTS^ 
 
 CHAPTER VI. 
 The Dark-Room — Development— Non-Actinic Room — 
 Transparent Dish for Holding the Plate during De- 
 velopment, 68 
 
 CHAPTER VII. 
 Developers— Intensifiers— Theoretic Views of the Develop- 
 ment — Developer — Art of Development — Benefit of the 
 Albumen Substratum— Fixing Solution — Intensification 
 and Toning of the Negative, 62 
 
 CHAPTER VIII. 
 To Varnish Negatives— To Prepare Negatives for the Solar 
 Camera and for Copying with a Camera— Collodion for 
 the Solar Camera Negative— Method for Collecting the 
 Silver from the Wash Water, etc.— Fixing Solution— Py- 
 rogallic Acid Developer— Collo-Protosulphate of Iron 
 Developer, 
 
 CHAPTER IX. 
 The Print, how to Make It— Preparation of the Paper— Sen- 
 sitizing of Albumen Paper— Fuming of Sensitized Paper 
 —The Printing Operation— To Prepare Terchloride of 
 Gold— Preparation of the Toning Bath— Fixing Solution 
 for Prints— Construction of the Washing-Tank— The 
 Drying-Frame— Mounting of Prints, . . . .82 
 
 CHAPTER X. 
 The Negative by the Dry Process— The Dry Tannin Process 
 —Acid Development— Alkaline Development— Tannin 
 Preservative— Time of Exposure, 100 
 
 CHAPTER XI. 
 To Prepare Transparent Positives— Positive Printing on 
 Glass by Means of the Camera— To Prepare Transparent 
 Positives by Contact Printing— Varnish for Transparent 
 Positives— To Prepare Dry Phites by Gordon's Process- 
 To Prepare Transparent Stereographs, . . . .107 
 
CONTENTS. 
 
 xi 
 
 CHAPTER XII. 
 To Prepare Opal or Porcelain Pictures by the Wet Process — 
 By the Collodio-Chloride Process — To Print Opal Pic- 
 tures by Development, 118 
 
 CHAPTER XIII. 
 To Prepare Ferrotypes or Melainotypes and Ambrotypes — 
 Development of an Ambrotype — Developers for the Me- 
 lainotype or Ferrotype— Black Varnish for Ambrotypes, 125 
 
 CHAPTER XIV. 
 The Solar Camera and Solar Enlargements — Direct Solar 
 Printing — Printing by Continuation or Development — 
 Formulas for Printing by Development, . . . 129 
 
 CHAPTER XV. 
 Vignette Printing — Various Modes of Vignette Printing, . 137 
 
 CHAPTER XVI. 
 The Magic Print, . . . . . . . 142 
 
 CHAPTER XVII. 
 "What to do with the Silver and Gold Residues— To Reduce 
 Chloride of Silver by the Wet or Galvanic Process to Pure 
 Silver — To Reduce the Chloride or Oxide of Silver by 
 Fire — To Reduce the Gold Residues, . . . .144 
 
 CHAPTER XVin. 
 Landscape Photography— Tents for Landscape Photograyhy, 148 
 
THE 
 
 PHOTOGRAPHER'S GUIDE. 
 
 CHAPTEE I. 
 
 PREPABATION OF THE GLASS PLATES FOR THE RECEPTION OF 
 THE COLLODION FILM. 
 
 It is almost unnecessary to assert, that the finest 
 and clearest plate glass is the best adapted for photo- 
 graphic purposes, the only objection is the expense. 
 K the practical photographer lays in a stock of glass 
 in large plates, it becomes necessary to construct a 
 table for the special purpose of cutting up the large 
 plates of glass into the sizes required. Any ordinary 
 table about four feet long and three feet wide will be 
 suitable for this purpose. Let the upper surface be 
 planed perfectly level and smooth, and afterwards 
 covered with green baize. Along two sides and one 
 end a slip of hard wood is fixed upon the baize ; this 
 slip is one inch wide and about one-sixteenth of an 
 inch in thickness ; that is, shghtly thinner than any 
 glass plate that may be required to be cut. These 
 slips are graduated into inches and fractional parts of 
 an inch along the two sides, beginning at the angle in 
 each case and proceeding to the left. A flat rule is 
 next required, about three feet and a half in length, 
 
 two inches wide, and half an inch thick ; it must be of 
 1 
 
14 
 
 THE PHOTOGRAPHERS GUIDE. 
 
 hard wood, and perfectly straiglit along the edges. 
 Finally, a glazier's diamond is the next requisite. The 
 operator must go to a glazier, if he does not know how 
 to use the diamond. He will learn more in five min- 
 utes in this respect than we could impart to him by a 
 lengthy description. The cut of a diamond on glass, 
 when correctly made, is Hke the cut of a sharp knife 
 when the edge of the blade is drawn along the surface 
 of a piece of wood; it is a wedge-like incision totally 
 distinct from a scratch. "When the cut is made, the 
 next thing is to separate the two parts ; this is effected 
 by partly bending and partly pulling the two pieces 
 assunder, beginning at one side and proceeding gradu- 
 ally, though quickly onwards, to the other side. Nat- 
 urally the incision made by the diamond must be 
 complete to the edge, otherwise the fracture will not 
 easily commence; and if the incision does not reach 
 the opposite side, the fracture may deviate from a 
 straight line at the part where the diamond cut is 
 defective. 
 
 The operator has to find out in what position his 
 diamond makes a cut, and not a scratch, and then he 
 can ever afterwards fix it in this position. 
 
 The glass cutting operation is performed on and 
 near the right end of the table; in consequence of 
 this, the left end is comparatively free and may be set 
 aside to receive the vice, etc., for poUshing the plates 
 with buckskin; whilst the drawer on the side will be 
 a suitable receptacle for the diamond, files, buffers, 
 buckskin, silk and linen cloths, and whatever else may 
 be needed in this department. A certain portion of 
 the drawer may be divided off into compartments for 
 
THE PHOTOGEAJPHEr's GUIDE. 
 
 15 
 
 the reception of the different sized plates used, as, for 
 instance, for card-pictures, cabinet-pictures, etc. 
 
 The plates being now in readiness for the next step, 
 the sharp edges are all abraded by means of a file kept 
 for this purpose. Whilst performing this work, the 
 back of the operator is turned towards the table, in 
 order that the fine particles of abraded glass may fall 
 upon the floor and not upon the green baize on the 
 table. 
 
 The next operation is to ascertain by actual trial 
 that each abraded plate will fit in the shield of the 
 plateholder ; for it is a very vexatious trouble to find, 
 after the plate has been covered, with collodion and. 
 sensitized, that it is too large for the holder. After 
 each trial, and when found correct in size, the plate is 
 put away in its special receptacle until required. 
 
 "Whether the plates have been used befoi-e, or not, we 
 recommend that they be placed in a bath of nitric acid 
 and water of the following strength : 
 
 Nitric acid ----- 2 ounces. 
 Water - - - - - 2 pints. 
 
 They may remain in this bath for six or eight hours; 
 by this steeping the old films of varnish and collodion 
 are easily separated, whilst with fresh plates the sur- 
 faces become thoroughly cleaned from adhering and 
 extraneous substances. Instead of the preceding bath 
 the following is also highly to be recommended: 
 
 CAREY lea's bath. 
 
 Water - 
 
 Sulphuric acid 
 Bichromate of potash - 
 
 - 2 ounces. 
 
 - 2 " 
 
 - 2 pints. 
 
16 
 
 THE PHOTOGRAPHEe's GUIDE. 
 
 The result is about the same whichever bath is 
 used. 
 
 The adhering films of varnish, collodion, and albu- 
 men are likewise easily removed by immersing the 
 plates in cold water and raising the latter to the boil- 
 ing temperature. This is the least expensive method 
 but not always the most convenient. 
 
 After the plates have thus received their first clean- 
 ing, or the first preparation preparatory to washing, 
 each one is taken and placed beneath the tap and sub- 
 mitted to a thorough washing with a clean sponge or 
 the fingers; the stream of water is finally allowed to 
 play upon either side in succession, and then the plate 
 is ready to receive a coating of albumen upon one side. 
 
 The best and easiest mode of preparing the albumen 
 solution in stock is probably the one lately published by 
 Mr. Ackland in his modified Fothergill process. The 
 author says it may be preserved in good condition for 
 years if kept closely corked, 
 
 " Separate the yolks from the whites of any number 
 of eggs, and to every eight ounces of albumen thus 
 obtained add twenty drops of glacial acetic acid pre- 
 viously diluted with one ounce of water; stir these to- 
 gether with a glass rod until intimately mixed, which 
 occupies about one minute; then, after resting one 
 hour, strain through coarse muslin, and to the strained 
 liquid add half a drachm of the strongest liquor am- 
 monise; then preserve in carefully corked bottles." 
 
 An ounce of this solution diluted with five ounces 
 of water forms a liquid which is suitable for the sub- 
 stratum on glass surfaces. Pour a sufficient quantity 
 of this solution upon the bottom of a clean flat porce- 
 
THE PHOTOGEAPHEk's GUIDE. 
 
 17 
 
 lain dish so as just to cover two slips of glass placed 
 along each end of the dish when lying flat, and remove 
 all bubbles with a small piece of paper. 
 
 Now take the plate of glass, which has just been 
 thoroughly washed, and resting one end upon the shp 
 of glass at the bottom of the dish, let the plate gradu- 
 ally fall upon the surface of the albumen until the 
 other end rests upon the second slip of glass. A silver 
 hook will be found very convenient for lowering and 
 raising the plate. Now raise the end, hft the plate up 
 and examine its surface. The difficulty in this opera- 
 tion consists in getting a clean surface free from aU 
 sort of particles. It frequently happens that such 
 particles are met with on the first film or two. In this 
 case, take the plate to the tap and wash off the albu- 
 men thoroughly and begin the operation over again. 
 As soon as the film is quite uniform and without flaw, 
 the plate is allowed to drain for a moment and then 
 put away on the rack to dry in a warm place where 
 there is no current of air to produce dust. 
 
 The drying racks referred to are made of strips of 
 corrugated iron; they are indispensable in the labora- 
 tory, and can be had of any of our photographic deal- 
 ers. Several of them will be needed where work is 
 done systematically and with care. 
 
 The application of this substratum of albumen saves 
 an immense quantity of labor in cleaning" and pohsh- 
 ing the glass surfaces by the old method with rotten 
 stone and dilute alcohol; but this saving of labor is 
 but a small part of the advantage gained. With the 
 albumenous substratum, specks, stains, silver reductions 
 on and under the collodion film will seldom or ever 
 
18 
 
 THE PHOTOGKAPHEr's GUIDE. 
 
 occvir; and we are not cognizant of a single instance 
 where the collodion film glided off the plate when the 
 albumen was beneath. 
 
 The film soon dries and is then indistinguishable 
 from the glass surface as far as appearance goes; but 
 the surface covered with this film can easily be distin- 
 guished in case the plates have been misplaced. Glass 
 itself is hygroscopic and retains the breath for some 
 time, whilst, on the contrary, the breath is scarcely 
 retained a moment on the side covered with the 
 albumen. 
 
 In large galleries this operation fills up idle time ; 
 and in this way a large stock of prepared plates is al- 
 ways on hand and ready at a moment's notice for the 
 next operation. But this brings us to the second 
 chapter. 
 
CHAPTER II. 
 
 PEEPARATION OF THE COLLODION ; AND THE MODE OP COATINd 
 THE ALBUMENIZED PLATES WITH COLLODION. 
 
 Collodion, for photograpliic purposes, consists of a 
 solution of pyroxyline, or gun-cotton in a mixture of 
 ether and alcohol, to which are added a certain quan- 
 tity of soluble iodides and bromides, or of either alone 
 according to the purposes for which it is intended. It 
 is not advisable that the operator should manufacture 
 his own gun-cotton ; for he can get it better and 
 cheaper from the dealers, and especially from the 
 chemists who devote their whole and sole attention to 
 its preparation. Nevertheless, we will give our read- 
 ers the formulas for the preparation of pyroxyline. 
 
 There are two distinct methods of making gun- 
 cotton ; the former is by means of a mixture of sul- 
 phuric acid and nitrate of potash ; and the latter of a 
 mixture of sulphuric and of nitric acid. Cotton is im- 
 mersed in either of these solutions and after remain- 
 ing a short time it is taken out, washed, and dried. 
 Apparently it has undergone no change ; but by 
 weighing the quantity of cotton before and after the 
 operation we shall find that, after this treatment, the 
 weight has been increased. Furthermore, common 
 cotton is insoluble in ether and alcohol; whilst gun- 
 cotton or pyroxyline is quite soluble in this mixture. 
 Before treatment, too, with the mixed acids cotton 
 will burn, it is true, but it is not an explosive ingre- 
 
20 
 
 THE PHOTOGEAPHEr's GUIDE. 
 
 dient, as it becomes after impregnation with one of 
 the compounds, oxygen and nitrogen arising from the 
 decomposition of nitric acid. 
 
 FIRST METHOD OF PREPARING PYROXYLINS. 
 
 Weigh out, in the first place, twelve ounces of pure 
 nitrate of potash, pulverize it and dry it thoroughly 
 before the fire; weigh also twenty-four ounces of sul- 
 phuric acid such as is found in commerce; further- 
 more, weigh out six drachms of clean and well-carded 
 cotton. If the specific gravity of the sulpuric acid is 
 1.84, one ounce of water is required; if it is as low as 
 1.836, no water is required; and if it is higher than 
 1.84, two ounces of water may be measured out and 
 kept in readiness. Separate the cotton into small 
 tufts, and place them also in readiness. 
 
 Having next provided a large porcelain evaporating 
 dish, fill it with hot water and let it remain until the 
 vessel is quite warm on the outside. Pour the water 
 out and wipe the dish. Now put in the nitrate of 
 potash, then the water and stir the mixture about for 
 a few seconds. The sulphuric acid is next added and 
 intimately mixed. Finally, the cotton is immersed 
 with rapidity, one tuft at a time, and pushed quite be- 
 neath the surface of the mixture and so that every part 
 may come in contact with the acid and salt. Work 
 the cotton about, by means of two glass rods, for 
 about four or five minutes, after the last tuft has 
 been immersed; at the expiration of this time the cot- 
 ton is taken out and thrown into a large pail of water, 
 where it is well stirred about by means of the glass 
 rods in order to get rid of the major part of the acid. 
 
THE PHOTOGBAPHEe's GUIDE. 21 
 
 It is now immersed in a stream of running water, dis- 
 integrated with the fingers, and washed for some time 
 until all acidity has been removed. If a stream of 
 water is not at hand, the washing operation is per- 
 formed in several changes of fresh water; and finally, 
 the pyroxyline, after a thorough wringing, is placed in 
 a vessel of water, made alkaline with a few drops of 
 ammonia. Separate the pyroxyline into small tufts in 
 order that every part may come in contact with the 
 alkali. After remaining in this water for several hours, 
 test the liquid with blue litmus paper; if the latter is 
 not changed in an hour's time, it may be concluded 
 that the acid has been entirely removed. 
 
 But now the pyroxyline has to be again washed in 
 several changes of water in order to remove every 
 trace of the alkali. This is a tedious operation, and 
 can easily be dispensed with where there is a regular 
 jet of water in the first instance to remove the 
 acidity. 
 
 Wring the pyroxyHne, and then separate the matted 
 tufts into thin layers, which may be dried in the sun 
 or on a water bath maintained at a moderate tem- 
 perature. 
 
 The weight of the pyroxyline will now be about 
 eight drachms. 
 
 SECOND METHOD OF PKEPABING PYROXYLINE, BY A MIXTUEE OP 
 NITEIC AND OF SULPHUEIC ACID. 
 
 Make use, as before, of the large, glazed earthen- 
 ware evaporating dish, which is first made warm by 
 floating it on hot water; then pour into it the follow- 
 ing acids: 
 
 1* 
 
22 THE photogkapher's guide. 
 
 Nitric acid, sp. gr. 1.37 - 6 fluid ounces. 
 
 Sulphuric acid, sp. gr. 1.84 - 12 
 Stir the mixture and ascertain the temperature by 
 means of a thermometer. When the thermometer has 
 sunk as low as 150° Fahr., immerse six drachms of 
 well-carded cotton, previously separated into small 
 tufts as before. See that every tuft is thoroughly 
 under the surface; now cover up the dish for ten 
 minutes. At the expiration of this time the cotton is 
 removed by means of the two glass rods; the excess of 
 acid is weU pressed out, and then the pyroxyhne is 
 plunged into a large bucket of water, and treated in 
 the same way as before described in regard to pyroxy- 
 line when prepared with nitrate of potassa, etc. 
 
 Ordinary nitric acid has the specific gravity 1.37, 
 but it is well always to test the strength before com- 
 mencing, because if it be stronger, the relative pro- 
 portion of the two acids will be different. 
 Take the following as examples: 
 No. 1. 
 
 Nitric acid, sp. gr. 1.42 - 9 fluid ounces. 
 
 Sulphuric acid, sp. gr. 1.84 - 9 
 
 Cotton - - - - 6 drachms. 
 
 No. 2. 
 
 Nitric acid, sp. gr. 1.40 - 8 fluid ounces. 
 Sulphuric acid, sp. gr. 1.84 - 16 
 
 Water 1 
 
 Cotton - - - - 6 drachms. 
 
 PREPARATION OF PLAIN COLLODION. 
 
 The pyroxyhne when thoroughly washed and dried 
 
THE PHOTOGBAPHEe's GUIDE, 
 
 23 
 
 may be preserved in pasteboard boxes for an indefi- 
 nite time. In order to make collodion of it, it lias to 
 be dissolved. It is well to keep a quantity of the dis- 
 solved pyroxyline in stock, always ready for mixture 
 with the sensitizing solution. This stock solution is 
 prepared as follows: 
 
 Sulphuric ether - - - 2 quarts. 
 
 Alcohol 1 quart. 
 
 Pyroxyline - - - - 12 drachms. 
 
 The pyroxyline soon dissolves in the above mixture, 
 which is well shaken and then put aside in the cellar 
 to settle and ripen. If the pyroxyline is pure and in 
 good condition, there will not be much sediment. 
 Whenever required for use, the proper quantity is 
 decanted from the upper and clear portion at the top 
 by means of a syphon or otherwise. This plain collo- 
 dion has considerable consistence and may be diluted 
 with alcohol contained in the iodizing solution. 
 
 PEEPAEATION OF BKOMO-IODIZED COLLODION. 
 
 It is better to keep in stock a sufficient quantity of 
 iodizing solution, by means of which a few ounces of 
 bromo-iodized collodion may be readily prepared. 
 Below will be found three different formulas for these 
 stock solutions : 
 
 Formula No. 1. 
 Landscape Photography. 
 
 Iodide of ammonium - - 144 grains. 
 Bromide of cadmium - - 120 " 
 Alcohol - - - - 12 ounces. 
 
24 
 
 THE PHOTOGEAPHEb's GUIDE. 
 
 Formula No. 2. 
 
 Portrait Photography. 
 
 Iodide of cadmium - - - 182 grains. 
 Bromide of ammonium - - 96 " 
 Alcohol - - - - 12 " 
 
 Formula No. 3. 
 
 Landscapes and Portraits. 
 
 Iodide of cadmium - - - 108 grains. 
 
 Iodide of ammonium - - 108 " 
 
 Bromide of ammonium - - 48 " 
 
 Alcohol - - - - 12 ounces. 
 
 Formula No. 4. 
 
 This formula contains no bromide. 
 
 Iodide of ammonium - - 144 grains. 
 Iodide of cadmium - - - 96 " 
 Chloride of magnesium - - 96 " 
 
 Alcohol 12 ounces. 
 
 These stock solutions have to be kept in a cool dark 
 place, together with the plain collodion; the cellar is a 
 very suitable place. They remain in their present 
 condition unchanged for an indefinite time. 
 
 PREPARATION OF IODIZED COLLODION. 
 
 Plain collodion - - - - 3 ounces. 
 Iodizing solution - - - - l ounce. 
 
 The first and second formulas contain five grains and 
 a half of the mixed bromo-iodides in each ounce of 
 solution; whilst the latter contains six grains to each 
 ounce. The proportions of the salts in the two first 
 
THE PHOTOGRAPHEk's GUIDE. 
 
 25 
 
 solutions are nearly those of their chemical equiva- 
 lents. 
 
 The quantity of pyroxyHne to each ounce of collo- 
 dion, diluted as indicated by the alcohol in the bromo- 
 iodizing solution, is six grains to the ounce. More or 
 less can be added as circumstances require. A more 
 consistent collodion may be used for very small plates; 
 whilst a thinner collodion may be found necessary for 
 large plates; that is, for all sizes above the four-fourth. 
 
 If the collodion is not quite clear and free from smaU 
 floating particles, it will be found necessary to filter 
 the solution before it can be used for coating the al- 
 bumenized plates. Glass filters are manufactured for 
 this special purpose, which allow the filtration to pro- 
 ceed without exposing the collodion to the atmosphere. 
 The glass tube with a small aperture at the closed end 
 is intended to furnish a passage for air from the re- 
 ceiver for a corresponding quantity of collodion that 
 has filtered through the cotton, that surrounds it at the 
 bottom, and that drops into the receiver. We prefer 
 drawing the end of the glass tube into a capiUary ter- 
 mination of half or three-quarters of an inch long; 
 this mode of construction succeeds in preventing the 
 rising of the collodion up the tube instead of passing 
 into the receiver, and of thus obstructing the filtration. 
 These glass filters are very reliable and almost indis- 
 pensable, if you aim at perfect productions. 
 
 In addition to the glass filters, collodion vials are 
 kept for sale. They are constructed in such a manner 
 as to prevent bubbles whilst the collodion is being 
 poured out upon the plate. They are arranged, too, so 
 as to allow aU particles and specks of dry collodion to 
 
26 
 
 THE photographer's GUIDE. 
 
 accumulate around the neck and not to fall upon the 
 collodion film. These cometless vials, as they are some- 
 times called, are also very useful and reHable in the 
 photographic laboratory. 
 
 Before the albumenized plate is coated with collo- 
 dion, ascertain in the first place which side is covered 
 with albumen, as previously indicated. Secondly, dust 
 off all particles from this surface by means of a broad 
 camel's hair pencil, which must stand in a convenient 
 position for this purpose, reared upon its handle. If 
 the weather is damp, too, you had better move the 
 plate a moment or two over a spirit lamp in order to 
 drive off all moisture ; the latter may be seen as it 
 volatilizes. Then let the plate cool. Hold the plate 
 by the left front corner between the thumb and first 
 finger of the left hand, whilst, if the plate be heavy, 
 the second finger lends assistance in bearing the 
 weight. The coUodion vial is then taken in the right 
 hand; now pour the coUodion upon the plate at the 
 right hand distant comer, and incline the plate gradu- 
 ally whilst you are pouring, so that the coUodion may 
 flow to the other distant and left hand comer and then 
 forwards toward the front. As soon as the plate is a 
 little more than one-half covered, you stop pouring out 
 any more coUodion, and aUow that, which has been 
 already poured upon the plate, to proceed to the front, 
 by inclining the plate, and so to accumulate near the 
 right hand anterior corner, where the excess is aUowed 
 to flow back again into the vial. WhUst this excess is 
 thus dropping off from the corner, osciUate the plate in 
 the direction of the edge, as if it were poised on this 
 corner; by doing so ridges on the coUodion film in the 
 
THE PHOTOGKAPHEr's GUIDE. 
 
 27 
 
 direction of the inclination, if the plate were quiescent, 
 may be avoided. As soon as the collodion ceases to 
 drop, or nearly ceases, raise the plate into the horizon- 
 tal position, and oscillate it now in the direction of the 
 flat surfaces; that is up and down gently; this motion 
 removes all reticulated ridges that might have been 
 formed by the preceding oscillatory motion; and the 
 collodion surface becomes quite smooth. 
 
 As soon as the film is no longer soft, when touched 
 with the finger, but yet not perfectly dry, the plate is 
 immersed in the silver bath. 
 
 There is a considerable knack in coating a plate suc- 
 cessfully with collodion, and this knack, like every me- 
 chanical operation of this nature can scarcely be ob- 
 tained otherwise than by practice. AH that we can do 
 is to point out the simplest and clearest method by 
 which the art can be obtained. 
 
 To coat very large plates with collodion requires the 
 aid of a pneumatic-holder, which contains at least two 
 suction discs; one of three would still be more expedi- 
 ent. This form of holder has just been patented; it is 
 an excellent aid in such and similar operations, and 
 can be attached in an instant to a plate by simply slap- 
 ping the discs with a smart quick blow upon the oppo- 
 site side of the plate to that which it is intended to 
 coat with collodion. A holder with a single disc is 
 sufficiently strong to hold any plate up to the four- 
 fourth size. Another arrangement is found to be very 
 efficacious in coating very large and heavy plates; plates 
 that are much too heavy and too large to be supported 
 by one hand. It is this: a strong walking cane, or, 
 still better, the handle of a broom is fixed perpendicu- 
 
28 
 
 THE PHOTOGEAPHEk's GUIDE. 
 
 larly in an aperture in the floor; the upper part is 
 rounded off into a semi-spheroidal shape, and a piece of 
 woolen cloth is tied over it. When about to coat the 
 plate, the following is the proceeding: with both hands 
 carry the plate and place it horizontally over the upper 
 end of the broom-stick, so that the center of the plate 
 rests on the woolen cloth; in such a position the plate 
 is easily supported, and, being balanced, it can be os- 
 cillated by means of the left hand in any direction 
 whatever. The woolen cloth protects the surface fi'om 
 being scratched, and, at the same time, prevents the 
 plate from shding off its support. The collodion is 
 poured upon the surface as before directed, and, as 
 soon as the surface is completely covered, the collodion 
 vial is laid aside, and the subsequent manipulations are 
 performed with the two hands acting in combination. 
 
 If the coUodion film is introduced iato the silver 
 bath before it has had time to congeal; that is, has be- 
 come dry and compact in structure so as not to be dis- 
 integrated by an impression from the finger, the film is 
 liable to spht up and break off in patches, or wholly, in 
 the subsequent operations of developing, fixing, etc. 
 On the other hand, if the film be too dry, it resists the 
 permeation of the silver solution and does not become, 
 in consequence, so easily and completely sensitized. 
 
CHAPTER ni. 
 
 THE NITEATE OF SILVER BATH, ITS PREPARATION, TROUBLES, 
 AND RENOVATION. 
 
 Nitrate of silver is a salt wMcli is sometimes adul- 
 terated; it is an advantage, therefore, to know how to 
 detect this adulteration before the bath is prepared. 
 Buy always the salt in the form of large flat crystalline 
 tables ; if the crystals have more the appearance of 
 common salt, it is a pretty certain indication that the 
 salt is not pure. 
 
 To make the indication certain, dissolve five grains 
 of the crystals in a drachm of water, and drop into the 
 solution hydrochloric acid as long as a white curdy 
 precipitate is produced; separate the chloride of silver, 
 thus formed, by filtration through paper prepared for 
 the purpose. Into the clear Hquid filtrate add another 
 drop of hydrochloric acid; if no curdiness is produced, 
 it is a sign that all the silver has been removed from 
 the solution, which, if the original salt was adulterated, 
 will contain the salt or salts used in the adulteration, 
 together with traces of hydrochloric acid. 
 
 Evaporate the filtrate to dryness; if nothing remains 
 on the evaporating dish, it is an evidence that the 
 silver salt was pure, unless nitrate of lead had been 
 used in the adulteration; in this case the lead salt will 
 be found on the filter. But if there is a whitish residue 
 on the evaporating dish, this may be weighed and put 
 down as so much impurity. 
 
30 
 
 THE photographer's GUIDE. 
 
 Mix a few particles of pulverized lime and some of 
 the wliite residue together, and moisten the mixture 
 with a drop of water. If nitrate of ammonia be pre- 
 sent in this residue, it wiU be decomposed by the hme, 
 and the fumes of ammonia will be set at liberty. The 
 absence of all smell of ammonia shows distinctly the 
 absence of an ammoniacal salt. In this case nitrate of 
 soda may be suspected. This salt burns hke salt- 
 petre when thrown upon a piece of burning charcoal; 
 and blotting paper impregnated with this salt in solu- 
 tion and dried forms touch-paper, which, when kindled, 
 bm^ns with a deflagrating noise, but without flame, un- 
 til it is totally consumed. 
 
 Supposing the impurity is nitrate of lead, it wiL. be 
 found now as chloride of lead mixed with chloride of 
 silver on the filter. Filter through the mixed chlorides 
 dilute nitric acid for some time. The chloride of lead 
 wiU be dissolved, and pass through the filter, leaving 
 the chloride of silver on the filter. Evaporate the so- 
 lution to dryness; if there be no residue, there is no 
 lead salt mixed with the silver salt. 
 
 Having in this way satisfied yourseK of the purity of 
 the nitrate of silver piu'chased, proceed further as 
 f oUows : 
 
 Take- 
 Rain water - - 2 quarts or 64 ounces. 
 Crystallized nitrate of silver - 6 " 
 
 Stir the salt in the water until it is dissolved. This 
 solution will contain a httle less than forty grains of 
 nitrate of silver to the ounce of water. Divide the so- 
 lution into two halves. 
 
THE PHOTO GEAPHEe's GUIDE. 
 
 31 
 
 IODIDE OF SILVER. 
 
 Take a drachm of tliis solution and add to it drop by- 
 drop a solution of iodide of potassium, as long as a yel- 
 low precipitate is formed; let the precipitate settle; 
 then decant the fluid portion and wash the precipitate 
 with a couple of drachms of water; let the precipitate 
 again settle, and finally pour away the supernatant 
 water. This yellow substance is iodide of silver. 
 
 Mix the iodide of silver with the one-half of the ni- 
 trate of silver solution and stir the mixture with a glass 
 rod. After standing for an hour, filter this solution 
 and then add it to the other half. 
 
 Now, throw a small piece of blue litmus paper into 
 the solution and let it remain a quarter of an hour. If 
 the color does not at aU change to red in this time, or 
 but exceedingly slightly, the bath will be in a proper 
 condition to receive the coUodionized plate. On the 
 contrary, if the blue color almost immediately becomes 
 red, this is a sign that the bath is much too acid; and 
 you have now to neutralize it with carbonate of soda, 
 or oxide of silver. Such an occurrence, however, will 
 seldom be met with, for pure nitrate of silver is a neu- 
 tral salt, that is neither acid nor alkaline; and an im- 
 pure salt you wiU reject at the very outset. Still we 
 wiU indicate the means of correcting this acid condition 
 where it does exist. 
 
 CARBONATE OF SODA. 
 
 The easiest method of neutrahzing a bath is that 
 with carbonate of soda; because oxide of silver is but 
 very feebly soluble in the cold solution. Dissolve a 
 drachm of carbonate of soda in a small quantity of 
 
THE PHOTOGBAPHEE's GUIDE, 
 
 water, and add of this solution drop by drop a suffi- 
 cient quantity untU the acidity is completely neutra- 
 lized. The bath must be weU stirred after the addition 
 of a few drops of the alkaline solution, and then tested. 
 
 OXIDE OF SILVER. 
 
 Take a drachm of the nitrate of silver solution and 
 add to it drop by drop a solution of caustic potassa as 
 long as a brown precipitate is formed; finally, allow 
 the precipitate to settle, and pour away the Hquid on 
 the top. Mix with the precipitate a couple of drachms 
 of water, stir the mixture well, and again allow the re- 
 sidue to subside. Decant again. Repeat this opera- 
 tion of washing two or three times; and at the end 
 separate the brown powder from the supernatant 
 liquid — this is oxide of silver. 
 
 Mix the still moist oxide of silver with the acid bath, 
 and stir it up well; boil the mixture, and then set it 
 aside for a number of hours. The free acid combines 
 vnth the oxide and forms with it a silver salt, which 
 probably is nitrate of silver; and the bath thus is ren- 
 dered neutral. The bath solution is again filtered. 
 
 It is quite an advantage to set a funnel aside always 
 for this special purpose of filtration; in this case it is a 
 very easy operation to filter the bath every evening, or 
 every week, according to the work done or the liabiHty 
 of the bath to receive dust and other impurities. The 
 filtering paper may be used over and over again re- 
 peatedly untn it finally gives way by some mechanical 
 rupture. Never be afraid of injuring the silver solu- 
 tion by filtration, as some have insinuated; the view 
 is erroneous; on the contrary, you avoid numerous 
 
THE PHOTOGBAPHEr's GUIDE. 
 
 33 
 
 troubles by always preserving the bath free from all 
 mechanical impurities. 
 
 The bath, which may be either of glass, photogra- 
 phic ware, or porcelain, is placed in an inchned po- 
 sition in the dark, or non-actinic room; in this room 
 the albumenized plates are coated with collodion, and 
 then directly immersed by means of a porcelain or glass 
 dipper in the silver solution. 
 
 Each bath ought to be furnished with a cover or Hd 
 to keep out both dust and Hght both during the opera- 
 tion of sensitizing and at every other time. In imme- 
 diate proximity with the bath it is advisable to fix a 
 glass funnel dipping into a receiver beneath. This 
 funnel must be a permanent fixture, and is intended to 
 receive the sensitized plate the moment it is taken out of 
 the bath. The plate rests in the funnel quite easily with- 
 out any danger of the collodion film being injured by 
 coming in contact with the sides of the conical shaped 
 funnel, a thing that is impossible. In this position the 
 excess of nitrate of silver di^ams from the plate and is 
 collected in the bottle beneath, from which, from time to 
 time, it can be returned to the bath. 
 
 As soon as the plate ceases to drop any more of the 
 silver solution, it is immediately transferred to the 
 plateholder for the subsequent operation of being ex- 
 posed. 
 
 But we have not yet finished with our discussion of 
 the bath solution. It is Hable to get out of order; and 
 it is necessary to know how to remove the troubles 
 that may occaisonaUy supervene. 
 
 The bath is most sensitive when it is in a neutral 
 condition, but in this condition the collodion film is 
 
34 
 
 THE PHOTOGEAPHEr's GUIDE. 
 
 apt to be fogged all over tlie surface in the subsequent 
 operation of development v^^ith. the ordinary iron devel- 
 oper; vv^itb the coUo-ferric developer this trouble of 
 fogging is not likely to occur. Whenever the film be- 
 comes fogged a drop or two of nitric acid have to be 
 added to the bath solution, and so long but cautiously 
 added until the evil is removed. We mean by fogging 
 that the film becomes covered with a veil or cloud, as 
 it were, which renders it all over sHghtly opaque, even 
 after the fixing of the image, or the removal of all sol- 
 uble iodides. But the most frequent cause of this fog- 
 ging is not to be attributed so much to the bath as to 
 the careless manner of exposing the plate during the 
 time that it is being sensitized, or after removing it 
 from the bath to the plateholder, to diflpQsed actinic 
 hght. Such a plate is exceedingly sensitive; and a 
 very small amount of common light will suffice to pro- 
 duce a great deal of damage in a very httle time. 
 Therefore, before any attempt is made to doctor the 
 bath with acid, see first that your light is in a proper 
 condition of non-actinism. Of this we shall speak in a 
 special chapter. 
 
 By repeated and long use the bath solution becomes 
 impoverished and deteriorated by impregnation with 
 foreign substances — substances introduced vsdth each 
 plate and produced by chemical decomposition or 
 otherwise. Thus let us examine what the collodion 
 film contains on its introduction into the solution. In 
 the first place, there is the collodion itself containing 
 pyroxyline, alcohol, and ether, and in addition, some- 
 times, the results of the partial decomposition of both 
 ether and alcohol, as well as impurities in the soluble 
 
THE PHOTOGKAPHEB's GUIDE. 
 
 35 
 
 cotton itself, as, for instance, free sulphuric acid or an 
 alkali. To these may be added the bromo-iodized 
 salts used in the photographic collodion. Thus, 
 then, the bath will gradually be rendered impure by 
 dilution with alcohol, and ether certainly, and with 
 other substances, such as sulphuric acid and an alkali, 
 probably. But by the chemical decomposition which 
 takes place immediately, when the collodionized plate 
 is immersed in the solution, we have, in addition to 
 the above nitrate of ammonia, nitrate of the oxide of 
 cadmium and other soluble nitrates, produced according 
 to what salts may be found in the bromo-iodizing 
 solution. 
 
 Now each collodionized plate introduces a little of 
 each and nearly of all of the ingredients enumerated, 
 on all occasions, certainly, a little alcohol, ether, and 
 of the soluble nitrates. These, by their gradual accu- 
 mulation, must have a tendency to put the bath out of 
 order and render it less efficacious than at the begin- 
 ning, when newly prepared. But by the mutual action 
 of nitrate of silver on each of these, or on each other, 
 other compounds are produced. The photographer, 
 therefore, will no longer be sm^prised that the silver 
 bath does get out of order ; in fact it would be sur- 
 prising if it did not. 
 
 But now the question arises : How can these troubles 
 be removed? or, if incapable of being removed en- 
 tirely, how can they be diminished ? 
 
 Mechanical impurities, such as dust and collodion, 
 and insoluble chemical precipitates or crystals, such as 
 the iodide of silver, bromide of silver and sulphate of 
 
36 
 
 THE photographer's GUIDE. 
 
 silver, can be easily removed by careful and frequent 
 filtration. 
 
 Volatile liquids, sucli as ether and alcobol, are di- 
 minislied to a minimum quantity by boiling or distil- 
 lation; by the latter method they may be collected in 
 a receiver and appHed afterward to some useful pur- 
 pose. 
 
 If iodide and bromide of ammonium were alone used 
 in the bromo-iodizing solution, the salt arising from 
 double decomposition in the silver bath would be 
 nitrate of ammonia; this salt might be removed en- 
 tirely by fusion and decomposition by heat, after the 
 bath had been evaporated to dryness, and nitrate of 
 silver would remain. But collodion seldom, if ever, 
 contains these two salts alone, and consequently all 
 other resulting nitrates would remain in fusion along 
 with nitrate of silver. 
 
 It is hence apparent, that an old bath cannot be 
 freed of its salts except by the decomposition of the 
 silver salt itself, and furthermore, that filtration and 
 distillation are the only means within our power of 
 making an approximation to the purification of the 
 silver bath. 
 
 Cyanide of potassium has been recommended as a 
 sure means of restoring a disordered bath; it is quite 
 certain that by dropping into the bath a drachm or so 
 of the solution, then by placing the bath in the sun for 
 several hours, and afterward by filtration, the silver 
 bath becomes momentarily wonderfully improved, but 
 it soon loses this quality and becomes finally worse 
 than it was before this treatment. 
 
THE PHOTOGEAPHEe's GUIDE. 
 
 37 
 
 Upon the whole, it is advisable, after an old bath, has 
 been used for a long time, and has been several times 
 boiled and subjected to distillation, to precipitate the 
 silver by means of a solution of common salt, to wash 
 and dry the residue, and finally reduce the resulting 
 chloride of silver to the metallic state by fusion. But 
 the operator will find no advantage in doing the work 
 himself; there are sUver and gold refiners who buy up 
 all such residues of silver and of gold, and make a 
 business of reducing them. Nevertheless, we shall de- 
 vote a special chapter to this department of a photo- 
 grapher's business, to which the reader is referred. 
 
 3 
 
CHAPTER IV. 
 
 THE SKY-LIGHT, SIDE-LIGHT, SCKEEKS, AND ACGESSOEIES FOR 
 POSIKG THE MODEL. 
 
 The department, upon whicli we now enter, is a sub- 
 ject of the most vital importance, and at the same time 
 the least understood, and consequently the least under 
 control. It has baffled the attempts of many an author 
 to describe, because it is a department of art as well 
 as of science. A combination of art and science can 
 alone solve the difficulties. 
 
 The first aim of the artist in painting is to obtain a 
 natural roundness and an agreeable contrast of light 
 and shade in his portrait; these properties not only 
 confer vitality to the inert pictm-e, but at the same 
 time this vitahty is sparkling, as it were, and pleasant 
 to behold. 
 
 This ought also to be the first aim of the photographer. 
 
 In order to attain to this desideratum the artist ma- 
 nipulates with his lights so long, not by guess, but in 
 accordance with the science of optics and of taste, 
 until his model is so placed as to present in person the 
 artistic model he wishes to copy. 
 
 The photographer must do exactly the same. 
 
 Let us here then present before our readers some 
 general principles. Place a globe on a pedestal and 
 let it represent the sitter's head. Let us suppose we 
 wish to make a picture of this globe so that it shall ap- 
 pear perfectly flat like a round table — how must the 
 
THE PHOTOGRAPHEe's GUIDE. 
 
 39 
 
 globe be illumined so as to give the appearance re- 
 quired ? 
 
 Shut out all the Hght except the one immediately in 
 front of it; or let the sun shine directly upon the sur- 
 face to be copied. 
 
 The globe itself will appear flat — and so will the pic- 
 ture, because the illumination is apparently equal all 
 over the surface. 
 
 By what means are solid objects depicted on a flat 
 surface so as to appear soHd ? 
 
 Firstly, by the conveyance of the lines of contour of 
 the given object to a given point or to given points; 
 and 
 
 Secondly, by shading the object more and more ac- 
 cording as the part becomes more and more distant. 
 
 Hence, if there is no difference m the illumination of 
 a given object, there wiU be no contrast of light and 
 shade, and consequently the picture wiU be in like 
 manner devoid of light and shade, and consequently 
 flat. 
 
 Can the globe be placed in such a position as to 
 be illumined most in front and then that the Ught gra- 
 dually becomes less intense to the edge of the illumin- 
 ated hemisphere ? 
 
 Kemove the globe back from the window ; and sup- 
 pose the window to be a small opening at the end of a 
 long corridor, which, when this opening is closed up, 
 would be quite dark; and let the ceihng, the side walls, 
 end, and floor be covered with black woolen cloth. 
 Then it wiU be evident by experiment, that, as the 
 globe is made to recede, its surface gradually will as- 
 sume more and more apparent roundness to the eye of 
 
40 THE photographee's guide. 
 
 the beholder; and this apparent roundness will be im- 
 proved until finally there is a balance between the 
 light and shade. If the globe be carried further back, 
 the balance wiU be destroyed by a preponderance of 
 darkness or shade. Thus, too much Hght, or too little 
 light, is equally opposed to the production of apparent 
 solidity in an object. 
 
 Instead of having an opening in the corridor at the 
 end, let this be closed up, and another be opened right 
 above the globe in the ceiling; and let the eye of the 
 spectator be placed on a level with 'the center of the 
 globe. What wiU be the phenomenon in this case ? 
 
 One-quarter of the globe alone wiH be visible, and 
 the most illuminated portion is that part which in re- 
 ahty is the most distant, and the nearest part; that is, 
 the part nearest the eye, receives the least amount of 
 hght; and thus, what one part gains in luminosity, it 
 loses in distance, and vice versa; so that here also the 
 idea or appearance of sohdity is destroyed. With such 
 a Hght we should have the same result, however dis- 
 tant the Hght might be removed from the globe, as long 
 as the eye preserves its position on a horizontal level 
 with the center of the globe. 
 
 We hence deduce, in general terms, that a vertical 
 Hght is altogether inferior to a horizontal Hght for the 
 iUumination of an object, that is intended to be so 
 shaded as to appear sohd when photographed, the eye 
 or the lens being supposed to be in the horizon of the 
 center of said object. 
 
 We deduce, furthermore, that a horizontal Hght, 
 when the Hght and the eye are in the same plane, will, 
 under all ordinary circumstances, produce a flat pic- 
 
THE PHOTO GEAPHEe's GUIDE. 
 
 41 
 
 ture, because it suffuses the object with an equal 
 quantity of light all over its surface. 
 
 But, if neither a single vertical, nor a single horizon- 
 tal light, unaided, will produce the proper illumination 
 of an object so as to exhibit the right contrast of light 
 and shade, that shall cause apparent sohdity, what 
 is to be done ? 
 
 "We must avail ourselves of every aid that presents 
 itself; and such aid may be derived from a combination 
 of Hghts, direct or by reflection; thus, in the case of 
 the vertical hght above mentioned, the eye in its pre- 
 scribed position could distinguish only one-fourth of 
 the sphere illuminated ; now let us arrange a large 
 white screen near the globe at an angle of forty-five 
 degrees with the floor, its central part being as high as 
 the center of the globe, we shaU perceive a much larger 
 part of the globe illuminated than before ; and yet the 
 light has not been changed either in its original direc- 
 tion, in quality or in quantity; but we have manipu- 
 lated with our hght, and made it subservient to our 
 wishes. 
 
 But we might have accompHshed the same object by 
 admitting a small quantity of Hght from an aperture, 
 and allowing it to arrive at the globe in the same di- 
 rection as that which was reflected. 
 
 What we here present are general principles; and 
 from these general principles it is required to elaborate 
 a system of hghts and reflectors (screens), by means 
 of which the sitter may be artistically suffused with an 
 agreeable contrast of light and shade. 
 
 As soon as the operator has once found out a posi- 
 tion for the model, and an arrangement of curtains and 
 
42 
 
 THE PHOTO&EAPHEE S GUIDE. 
 
 screens in a given room, wliicli will produce tlie best 
 effect of light and shade, he can ever afterward fix his 
 model and reproduce his arrangements. All this is 
 very easy; but in case a group has to be photographed, 
 he will frequently be greatly perplexed unless he makes 
 himself quite famihar with the general principles which 
 we have endeavored to inculcate. 
 
 With these few hints we will now proceed to the 
 sky-light, etc., which form an essential part of a pho- 
 tographic estabhshment. 
 
 As a general rule the photographer's glass-room is 
 found in the upper story of a building, and in such a 
 position that the adjoining buildings are not higher, 
 and where there are no trees, steeples, or chimnies to 
 cast shadows upon the roof. 
 
 The best position of a house for this purpose is when 
 the roof runs directly East and West; still it is possible 
 to get along with any direction, and to fix or construct 
 the hghts accordingly. 
 
 Taking then the normal condition, in which the roof 
 runs East and West, the floor of the garret is removed, 
 in order to allow the sky-light to be as far remote as 
 possible from the sitter. Upon the side of the roof 
 which inclines to the North the sky-light is to be con- 
 structed, and continued, after it arrives at the eaves, 
 until within a couple of feet of the floor. The distance 
 from the East and West walls must be from twenty to 
 thirty feet at least. In this case half the width of the 
 roof either on the East or West side can be devoted to 
 the sky-Hght and side-light, both, of course, looking 
 North. Curtains are arranged in parts with puUeys 
 and cords, so as to cover both of these windows en- 
 
THE PnOTOGRAPHEU's GUIDE. 
 
 43 
 
 tirely or partly according to circumstances. It is well 
 to liave two sorts of curtains, one set opaque so as to 
 shut out the light altogether, and the other set of blue 
 or white semi-transparent material intended simply to 
 modify the light. 
 
 In an ordinary sized building, three-fourths of the 
 whole flight is devoted to the glass-room, the remain- 
 ing portion being set apart for other purposes, such as 
 dark-room, printing, or store-room, etc. 
 
 If the roof of the building runs North and South, 
 and said building is isolated from other edifices, a sky- 
 light is constructed on either side of the roof, and the 
 Northern end, at least, a portion of it, is devoted to 
 the side-Hght. These three windows are all furnished 
 with movable opaque curtains or screens designed for 
 excluding the direct light from the sun when in the 
 East or in the West, or portions of light in certain 
 directions. 
 
 The plans which we have described are such as may 
 be followed, when the building is already constructed; 
 but little alteration is needed in the general form of 
 the original construction, and consequently the ex- 
 pense will not be very great; but if we had to construct 
 a model glass-house, our plan would be different from 
 the preceding. The Southern half of the upper part 
 of the house we would devote to the posing-room 
 proper, the background being placed near the South 
 wall, whilst the sitter looks toward the North. Along 
 the middle of the other half an alley is constructed for 
 the camera, A general idea of the outer form of our 
 model glass-house may be given by imagining two 
 boxes placed endwise in contact, but one of them being 
 
44 
 
 THE PHOTOGEAPHEe's GUIDE. 
 
 twice as liigli as tlie other. The tall one represents the 
 posing-room, the low one the gallery for the cameras, 
 in connection with each other. On the roof where the 
 two parts join the sky-Hght is constructed, having an 
 inclination of forty-five degrees; and on either side 
 there is a side-light to within a couple of feet to the 
 ground. All these hghts are furnished with curtains 
 and opaque shutters. Only one side-hght is used at a 
 time in portraiture. On either side of the avenue de- 
 voted for the camera, are side-rooms for various pur- 
 poses, such as toilet-rooms, stock-rooms, dark-rooms, 
 etc. The intention of this arrangement is to keep the 
 camera in as dark a place as possible, in order that the 
 space between the camera and sitter may reflect but 
 little light into the lens ; for it is impossible to obtain 
 a bright picture on the ground glass when the space 
 referred to is full of hght; there is no contrast; in fact 
 in such a case, where your room is full of light, you 
 would be taking a picture of the atmosphere rather 
 than of your sitter; and your work would always be 
 unsatisfactory. 
 
 Illumine your sitter but not your room ! 
 
 The glass employed for such lights is, when all 
 things are considered, the ordinary strong and color- 
 less crown glass. With a convenient and proper ar- 
 rangement of curtains and bhnds, there is no particu- 
 lar advantage, if any at all, in having the windows 
 glazed with blue stained glass, ground glass, or glass 
 painted either of a dead blue or white. These all more 
 or less obstruct actinic light, and there are times when 
 all the light, that can possibly be obtained, is required. 
 Still we must guard the reader against supposing that 
 
THE PHOTOGRAPHEb's GUIDE. 
 
 45 
 
 negatives are good according to the quantity of light 
 that has access intathe gallery; the truth is frequently 
 just the contrary; that is, a very small amount of Hght 
 frequently will produce a better picture than an un- 
 limited quantity. 
 
 The walls and ceiling of the glass-room must be 
 painted of a dead bluish-gray color, or a gray-drab; 
 and the floor must be covered with a carpet of similar 
 colors. The backgrounds are made of woolen cloth, or 
 some material in imitation of woolen cloth. One side 
 may be gray, and the other white ; or separate back- 
 grounds may be used each of a different shade. Pic- 
 torial backgrounds in monochrome are sometimes very 
 appropriate ; but the operator must always bear in 
 mind that in portraiture the background is a second- 
 ary matter, and must not be made the most prominent 
 part of the picture. By placing the background more 
 remote from the sitter, it will be more out of focus and 
 less distinct in the picture; with this knowledge the 
 artist can arrange the background so as to produce the 
 effect required. 
 
 In addition to the backgrounds, a number of swing 
 screens covered with white cotton cloth are required 
 to be used as reflectors. For, supposing the model is 
 placed with his back nearly South-West, and his face 
 looking North-East, it is evident that a portion of the 
 right side of his head and face will be too much in the 
 shade. To obviate this defect a screen is placed at 
 some distance South of the sitter and facing the North, 
 and at such an angle as to reflect a sufficient quantity 
 of light to relieve the deep shadows on the side of the 
 face in question. 
 3* 
 
46 THE photographer's guide. 
 
 The sitter must be placed back toward the South 
 side, and far enough to escape the vertical rays from 
 the sky-light, otherwise the upper part of the head 
 will be illumined disproportionately with the rest of 
 the body; and large shadows wiU be produced beneath 
 all the prominent parts of the head and face, as the 
 nose, eyebrows, cheekbones, etc. The tendency of 
 such a hght will be also to flatten the head in the pic- 
 ture, as we have already mentioned in reference to the 
 illumination of a globe. 
 
 In fine, place the sitter so that there are no deep 
 shadows on the eyes, beneath the nose, or on the neck; 
 let there be only one reflected star on each eye; this 
 can be effected by means of the curtains; let one side 
 of the face be slightly more luminous than the other, 
 the brightest parts being those which are most an- 
 terior; let the eye of the beholder, or the lens of the 
 camera be a trifling distance above the elevation of the 
 eye of the model; if it were otherwise, the opening of 
 the nostrils would be quite visible and unpleasantly 
 depicted in the picture. Place the sitter in a comfort- 
 able, easy, and natural posture; and when accessories 
 are to embellish the picture, such as a piano, table, etc., 
 let them be appropriate to the sex, profession, or con- 
 dition. It is absurd to attempt to make a fitness of 
 things where it was never intended; it is a constraint 
 that makes a picture ludicrous. 
 
CHAPTER V. 
 
 LENSES AND CAMERAS. 
 
 The lenses used in portraiture, are all, or nearly all 
 of them, constructed after the same formulas. In a 
 work hke this, which is designed for the practical oper- 
 ator, it would entirely be out of place to discuss these 
 formulas, which are intelligible only to the physico- 
 mathematican. Such lenses are caUed portrait or 
 compound lenses to distinguish them from lenses of 
 apparently a much more simple construction which are 
 used in landscape photography. 
 
 The anterior part of the portrait combination con- 
 sists of two lenses cemented together with Canada bal- 
 sam, which makes them appear Hke one lens. The 
 first or outer lens is constructed of crown glass, and is 
 double convex; the inner lens is double concave, and 
 of flint glass. It is easy to distinguish these two sorts 
 of glass: flint is colorless, or if slightly tinged it is 
 with that of a very faint yellow; but crown glass a 
 faint greenish hue. Remember, the convex part faces 
 the sitter. 
 
 In the middle of the tube and between the two len- 
 ticular combinations is found what is called the dia- 
 phragm or stop, being a piece of blackened brass with 
 a central aperture. In some portrait combinations 
 the stops are movable and are furnished with apertures 
 of dilferent diameters. The intention of these stops is 
 this : the central and the peripheral part of a lens pro- 
 
48 
 
 THE PEOTOGEAPHEb's GUIDE. 
 
 duce pictures, it is true, independently of eacli other, 
 but not at the same distance from the lens. This pro- 
 perty can easily be verified by sticking a round disc of 
 leather upon the central part of a lens and then focus- 
 sing some object on the ground glass. The picture in 
 this case is formed by the glass ring external to the 
 leather disc. Now remove the disc of leather, and 
 place upon the lens in its stead a piece of leather as 
 large as the lens, but of which the central portion was 
 the disc previously. In this case the light passes only 
 through this central part. Focus again the same ob- 
 ject upon the ground glass. You will find you have to 
 increase the distance between the lens and the ground 
 glass, or that the focus for the outside or central por- 
 tion of a lens is longer than that of the external or 
 peripheral part of a lens. Hence, it is impossible, 
 under ordinary circumstances, to obtain a sharp pic- 
 ture of an object with the full opening of a lens; for 
 points and hues that are out of focus become converted 
 into surfaces; and we see that if we focus with the 
 central part of the lens, the rays that come to a focus 
 from the outside part will form their sharp picture in 
 front of the ground glass. In consequence of this, 
 stops are used for excluding aU the peripheral rays; 
 and the smaller the aperture in the diaphragms the 
 sharper the picture. But there is a limit to this ad- 
 vantage; the aperture may be so smaU as to allow but 
 little light to pass through it, and, although the pic- 
 ture that is thus formed is very neatly defined, it is 
 but very faintly luminous ; but luminosity produces 
 photographic or chemical action on the prepared plate ; 
 and this action varies in magnitude with the quantity 
 
THE PHOTOGRAPHEB's GUIDE. 
 
 49 
 
 of liglit; so tliat when the luminous picture on the 
 ground glass is faint, it will fail partially or totally to 
 produce any impression on the chemically prepared 
 surfaces. In landscape photography, when the con- 
 densation of light is very great, the smallest aperture 
 may be used; whereas, in the glass-room, there is but 
 a small surface, comparatively speaking, that trans- 
 mits its hght through the lens, we are obliged to use 
 the largest stop. 
 
 The posterior lens is also a combination of two 
 single lenses, but these are not cemented together. 
 The inner one, that is, the one next after the dia- 
 phragm consists of flint glass; it is concavo-convex in 
 form, the convex side looking toward the center of 
 the tube. Between this and the last lens there is a 
 small brass ring which keeps the two lenses apart. 
 The last lens is a double convex lens, but the inner 
 surface is more convex than the outer one. The rea- 
 son of this variety of lenses, so as to produce a work- 
 ing combination, is not intelligible to any one who has 
 not made the subject of optics an earnest study. You 
 have seen that the peripheral parts of a lens act differ- 
 ently from the central parts in converging rays to a 
 focus; and that diaphragms are apphed to remedy the 
 evil; now you must proceed a step further and learn 
 that, when light passes through a lens, whether con- 
 vex or concave, it undergoes a change in passing 
 through; before it entered, it was colorless; now when 
 it makes its exit, it is colored. Another step teaches 
 us, that lenses made of one sort of glass have the pro- 
 perty of correcting the color produced by a lens of 
 another sort of glass. Thus the light that passes 
 
50 
 
 THE PHOTOGBAPHEr's GUIDE. 
 
 througli the front double convex lens of crown glass 
 becomes colored by this passage ; but the double con- 
 cave lens of fiint glass, being placed immediately be- 
 hind it, receives the colored rays and restores them 
 partially to their original colorless condition. Other 
 combinations succeed in order, whose function it is to 
 complete the restoration, and still aUow a residual 
 quantity of convexity of sm-face to remain in order to 
 converge the rays as they finally pass out; for without 
 convergence there can be no picture. 
 
 For landscape photography the same sort of lens 
 can be used as for portraiture; but one of less costly 
 construction wiU answer the purpose equally well ; it 
 is also much lighter in weight, and hence more port- 
 able. Many of our portrait combinations are so ar- 
 ranged that the front lens can be used singly for land- 
 scapes, whilst the two are required for portraits. In 
 such combinations, the back lens is not so much re- 
 garded as a corrector of the front lens, but as an addi- 
 tional lens which shortens the focal length of the com- 
 bination, and hence produces a greater condensation 
 of Hght which is capable of making the photographic 
 or actinic impression on the prepared chemicals, and 
 which a single lens would be incapable of effecting. 
 
 The view lenses proper are found in the market 
 under various forms; those of Jamin consist of a single 
 combination of two simple lenses cemented together 
 with Canada balsam. Several others are of the same 
 construction. The stop or diaphragm is placed in 
 front of the combination, and the latter is generally 
 turned right round, so that the lens which is posterior, 
 when it is used in portraiture, becomes placed in front 
 
THE PHOTOGBAPHEr's GUIDE. 
 
 51 
 
 for landscapes. But, as before remarked, a combina- 
 tion of two lenses can never be made to correct the 
 whole amount of decomposition of Hght; hence, such 
 view lenses, although in many instances exceedingly- 
 excellent, have not the same reputation as combina- 
 tions of three simple lenses so as to form triplets, 
 which, when the formulas are properly calculated, and 
 the curves carefully ground in accordance, can correct 
 the decomposition more effectually than a doublet, in 
 the ratio of two to one. The simple lenses of such a 
 triplet may be either cemented together as one lens, 
 or combined according to some optical principle at 
 given distances apart. The view lenses of Dallmeyer 
 and Koss, made in this form, are equal in every re- 
 spect to the very best in any country, and by many 
 photographers they are regarded superior to aU others. 
 
 The Globe lens is a very happy combination of two 
 pairs of compound meniscuses, which, when mounted, 
 are in the form of a globe. The stop is in the middle 
 between the two compound meniscuses. The correc- 
 tions for both the spherical and chromatic aberrations 
 are nearly perfect; and the angle of view is very large; 
 it is a very favorite lens among our American photo- 
 graphers. Dallmeyer's wide-angle lens wiU perform 
 all that the Globe lens can do, and has the advantage 
 of using more hght. 
 
 The SteinheU periscopic lens is in fact a Globe lens, 
 consisting, however, of two simple meniscuses of the 
 same sort of glass; it is mounted hke a Globe, with a 
 central stop. The chromatic correction is effected in a 
 very curious way, which has hitherto not been recog- 
 nized by opticians as possible. The angle of view in 
 
52 
 
 THE PHOTOGEAPHEb's GUIDE. 
 
 this combination is also very large; but its action is 
 said to be very slow; and on that account it will 
 scarcely ever compete with the Globe and the Wide- 
 Angle lens. 
 
 The Orthoscopic combination is another form of lens 
 which may be used for taking views. It consists of two 
 combinations of two lenses each. The angle of view of 
 this form of lens is much more contracted than that of 
 the Globe or the Wide-Angle lenses of Boss and Dall- 
 meyer ; it derives its name from the fact, that straight 
 Hues in a chart or map are exhibited straight or ortho- 
 scopic in the copy. But the Globe or the Wide-Angle 
 lens will also do this orthoscopic work more quickly 
 and to a greater extent. The optical construction be- 
 tween the Globe and the Orthoscopic lens is quite dif- 
 ferent; so much so that the former may be said to be 
 corrected with positive or convex lenses for both spher- 
 ical and chromatic aberration; whilst the latter is cor- 
 rected with negative or concave lenses. 
 
 The lenses from abroad which have gained the high- 
 est reputation here are those of Voigtlander, Boss, 
 Dallmeyer, and Jamin; but we do not need any longer 
 to avail ourselves of foreign aid in this respect; the 
 portrait combinations of two or three of our native op- 
 ticians in this country, for instance those of Willard & 
 Co., Am. Optical Co., Chapman & Wilcox, and Eoettger 
 cannot be surpassed for accuracy of workmanship; and 
 the Globe lens for copying and landscape operations 
 stands pre-eminent. 
 
 CAMERAS. 
 
 There are various forms of cameras according to the 
 purposes for which they are intended. The requisites 
 
THE PHOTOGEAPHEe's GUIDE. 
 
 53 
 
 in a camera are that it shall be rigid and yet ligtt ; 
 the ground glass must be perpendicular to the opti- 
 cal axis of the lens, and its motion must be even 
 and always remain perpendicular to the axis. In 
 large cameras the ground glass has two motions, a 
 quick and a slow motion, by which the focussing can 
 be easily effected without touching the lens itself. This 
 is convenient. For taking card-pictures the camera is 
 generally constructed so as to allow the plateholder to 
 shde into different positions by means of which several 
 pictures of the same sitter can be taken on the same 
 plate. If, moreover, there are two or four lenses on 
 the same camera, and the plateholder also sHdes, a still 
 larger number of pictures can thus be taken at the 
 same sitting. 
 
 Stereoscopic cameras are always constructed for the 
 reception of two lenses of equal power; but with a 
 shding plateholder stereoscopic negatives can be taken 
 with a single lens. In this case, however, the camera 
 must also be made to slide into a position two inches 
 and a half either to the right or the left of its first po- 
 sition after the first exposure, according to whether 
 the right side picture was taken first, or the left side 
 picture. 
 
 Cameras are now manufactured with such a degTee of 
 perfection, that it is needless to enumerate the troubles 
 that photographers had to expect in former times. 
 
 Above aU things, however, ascertain at the outset 
 whether the ground glass and the negative glass are 
 exactly at the same distance from the lens. To do 
 this, put a plate of flat glass into the holder and draw 
 the shde. Lay a straight and flat ruler over the edges 
 
•54 
 
 THE PHOTOGKAPHEB's GUIDE. 
 
 of tlie frame and measure the height of the upper side 
 of the ruler from the surface of the glass below; move 
 the ruler about over different parts of the surface and 
 measure the height. If this height remains the same all 
 over the surface of the glass plate, it is an evidence that 
 the glass corners have been accurately set. Now lay 
 the ruler over the fi-ame of the ground glass, in differ- 
 ent parts, and measure the corresponding height; if 
 these are all the same, and also correspond exactly with 
 that of the negative glass, the construction of these 
 two parts is correct and accurate. 
 
 TO MAKE THE ACTINIC FOCUS AND LUMINOUS FOCUS 
 COINCIDENT. 
 
 It may happen that, however accurately the ground 
 glass and the sensitized plate may coincide in distance 
 from the lens, and however correctly you may have 
 focussed, yet the picture on the negative is not as sharp 
 as the picture on the ground glass. This is caused by 
 the non-coincidence of the actinic focus and the lumin- 
 ous focus; that is, the compound lens has been either 
 over-corrected or under-corrected. If a lens has been 
 perfectly corrected, aU the rays of the spectrum come 
 to a focus at one and the same point ; in an un- 
 corrected and under-corrected lens, the blue, that is, 
 the actinic rays come first to a focus; whereas in an 
 over-corrected lens the luminous rays are brought first 
 to focus. 
 
 The actinic focus is- the focus of the picture on 
 chemically prepared paper. 
 
 The luminous focus is the focus of the picture on 
 the ground glass. Hence, if the lens has not been 
 sufficiently corrected, the luminous picture on the 
 
THE PHOTOGKAPHEr's GUIDE. 
 
 55 
 
 ground glass 'will be more distant than the actinic pic- 
 ture on the sensitized plate; and it remains for you to 
 find out by actual experiment how much the difference 
 of distance is. Put in a piece of cardboard between 
 the edges of the ground glass and the flange upon 
 which it rests, and try if this improves the picture on 
 the sensitized plate ; if this has improved the result 
 but not completely cured the defect, add another thick- 
 ness of cardboard until you have overcome the diffi- 
 culty. 
 
 But if the lens has been over-corrected, the ground 
 glass must be gradually sunk deeper in its frame until 
 the desired correction has been attained. 
 
 Secondly, see that there are no pinholes or screw- 
 holes by which Hght can find access into the interior 
 of the camera, excepting through the lens. 
 
 See, too, that the spring valve of the plateholder 
 opens and closes accurately when the slide is put in or 
 taken out. 
 
 Whenever accessories have to be taken together with 
 the portrait in the picture the camera must be hori- 
 zontal ; for if it be tilted, perpendicular objects are 
 tilted also, and will be represented as such in the pic- 
 ture. But when the portrait alone is taken, it is cus- 
 tomary to raise the back of the camera, so that the 
 lens is inclined downward in order to look down upon 
 the sitter. In this way a position can be found where 
 every part of the model will be nearly aU in focus. 
 
 To focus with ease and accuracy it is better to have 
 a large opaque cloth tacked to the front frame of the 
 camera all round the top and the two sides, and suffi- 
 
56 
 
 THE photographer's GUIDE, 
 
 ciently long as to cover tlie head and shoulders of the 
 operator whilst he is examining the picture on the 
 ground glass. A pair of good spectacles wiU also be 
 found exceedingly useful in making the focus quite 
 sharp. It is customary to bring the eye of the sitter 
 into accurate focus. This can easily be done, for 
 the inner corner of the eyehds is a very visible 
 object. 
 
 See that the head rest is nowhere visible, nor any- 
 thing else that ought not to be seen. Place the sitter 
 so that almost every part of his body is nearly at the 
 same distance from the lens. To do this the model 
 must sit sidewise, turning his head to the front. Let 
 the position be graceful, easy and natural. If any 
 part, such as the hand, or knee, etc., be too much out 
 of focus, let the position be changed until the picture 
 is satisfactory. Adjust the robes, ribbons, ringlets, 
 etc., of your sitter, which do not flow or sit in artistic 
 forms, and direct your model to regard some small 
 and easily seen object, by which the eyes are in no way 
 constrained nor the face forced into a stare. When aU 
 is thus adjusted, put the cap on the lens, remove the 
 ground glass and substitute the plateholder contain- 
 ing the sensitized plate. Draw out the slide and wait 
 a moment to allow the camera to be quite at rest. 
 Your model must now regard the prescribed object; 
 take off the cap from the lens and count the 
 seconds. 
 
 It is always an advantage to have a clock furnished 
 with a seconds' hand, in sight from your present 
 position, so that you have no trouble with your watch; 
 
THE photographer's GUIDE. 
 
 57 
 
 and the spectacles that you use to focus with, had al- 
 ways better be left in a given place in or near the 
 camera, for it is too much trouble to put them in your 
 pocket and then have to take them out again when 
 wanted. 
 
 Close the cap and the sUde. Carry the plateholder 
 into the dark room. 
 
CHAPTEK VI. 
 
 THE DARK-ROOM — DEVELOPMENT. 
 
 In former times tlie room in which the pictures 
 were developed, the plates sensitized, etc, was prop- 
 erly called a dark-room — it was dark, gloomy and dis- 
 agreeable. It is no longer so now. From discoveries 
 that have been made, this developing room may be the 
 lightest room in the establishment, as long as the light 
 is of the proper color. Let the window of the room 
 be glazed with orang-red colored glass, and in ad- 
 dition fix up a curtain of thin red woolen cloth or 
 flannel. The light that passes through this window 
 exercises no action upon the sensitized plate; you may 
 develop the plate in front of this window without any 
 danger of fogging the impression. But be sure to 
 shut up every avenue to white hght; the smallest beam 
 of this light is detrimental to your success; the Hght 
 that comes through the keyhole is injurious. 
 
 This room ought to be called the non-actinic room, 
 because the light with which it is suffused is non- 
 actinic, which means, that it has no action on pre- 
 pared chemicals. 
 
 It is well to try the efficacy of your non-actinic 
 room by experiment. Sensitize, therefore, a coUodion- 
 ized plate, and then expose it to the light which en- 
 ters through the orange-red window for two or three 
 minutes. Pour on the developer in the usual way. If 
 the plate does not change color in the least, it is an 
 
THE PHOTOGEAPHER's GUIDE. 
 
 59 
 
 evidence that actinic light, at least, has not made any 
 impression upon it, and you may then, with full con- 
 fidence, afterward perform all your developing opera- 
 tions with ease and certainty. 
 
 To facihtate the operation still further, we always 
 prefer developing by the aid of a light which comes 
 from below, and thus shows the progress of develop- 
 ment by transmitted Hght. For this purpose let the 
 developing corner or table be a projection beyond the 
 wall of the building, and let a large square of non- 
 actinic glass be glazed in an aperture on the top of 
 this table; this pane can admit Hght only from below 
 upward. 
 
 During development the plate, whether large or 
 small, may be held, it is true, between the thumb and 
 finger, but it is much easier to hold it supported on a 
 pneumatic plateholder. In this position you can cover 
 the plate with the developing solution with the utmost 
 facility. It requires some experience before you can 
 flow the developer evenly without any stoppage or in- 
 terruption; the operation must be quick, and yet it 
 must not be violent, otherwise much of the developer 
 wiU rush off at the opposite side, and carry with it 
 much of the free nitrate of silver which was still on 
 the plate, and which is so very beneficial in producing 
 intensity. If the ^developer proceed slowly over the 
 exposed film, the development wiU be uneven, one 
 part being already out before the other has com- 
 menced. If the developer stop and refuse to proceed 
 in a given direction, there will assuredly be found in 
 the finished negative a dark Hne or curve at that 
 place, which will be very offensive in the print. 
 
60 
 
 THE PHOTOGEAPHEr's GUIDE. 
 
 Furthermore, if the developer be poured from a 
 great height (and we regard two or three inches high 
 in this experiment), its momentum the moment it 
 comes in contact with the collodion is sufficient to 
 wash off the impressed silver from this part, and to 
 produce, in consequence, a very weak patch at this 
 spot. To avoid aU these troubles, and especially with 
 a large plate, we prefer laying it at the bottom of a 
 dish of gutta-percha at one end. In this case, the dish 
 being sHghtly tilted, the developer can be poured into 
 the opposite end in sufficient quantity to cover the 
 plate the moment it is again raised to a horizontal po- 
 sition or tilted in the opposite direction. This is a very 
 effectual plan of development, and, especially so, if the 
 dish has a transparent bottom, for then you can watch 
 the development by transmitted Hght. 
 
 A transparent developing dish is constructed in the 
 following manner : Take a thin piece of hard and well 
 dried wood, four or five feet in length, one inch wide, 
 and half an inch thick, and plane a groove along the 
 middle about three-sixteenths of an inch deep, suffi- 
 ciently large to allow the edge of an ordinary pane of 
 glass to sHde along it. Four lengths are then cut out 
 so as to make a rectangular frame, the ends being cut 
 in a miter-box at an angle of forty-five degrees. A pane 
 of glass is then tightly framed in the groove; and the 
 frame is firmly nailed together. After this is done, a 
 cement consisting of five parts of resin, one part of 
 beeswax, and one of red ocher are melted together, 
 and when fluid a sufficient quantity is poured along 
 each seam or groove all round on either side, and 
 along all the corners. After the cement has set, the 
 
THE photographer's GUIDE. 
 
 61 
 
 excess is pared off and polished down smootli with a 
 red hot pointed piece of metal. The frame is finally 
 covered with a coat of varnish, made by dissolving 
 sealing wax in alcohol, in a teacup, over the stove. 
 Coach or any other varnish will answer the purpose. We 
 have a set of such frames, of different sizes, for the dif- 
 ferent sized plates in use. Each transparent plate is at 
 least two inches longer than the plate to be developed; 
 the excess of length is the part which is to receive the 
 force of the developing fluid as it falls out of the vial 
 which contains it. If the jplates to be developed are 
 very large, the dish that is to hold them may be con- 
 structed so as to have two projecting handles, either 
 screwed on to the ends of two parallel sides, or formed 
 out of these two sides themselves, which are left pro- 
 jecting some four or five inches beyond the ends. The 
 dish and plate are then easily supported by the two 
 hands, whilst an assistant pours on the developer. 
 
 3 
 
CHAPTEK Vn. 
 
 DEVELOPEKS INTENSIFIEES. 
 
 The image on, or in the collodion film, after ex- 
 posure, is a latent or invisible picture of the object upon 
 which you focussed; by the application of certain 
 chemical solutions to the collodion film, the image, be- 
 fore latent, gradually emerges from its prison-hold 
 into being. Such chemical solutions are called devel- 
 opers; these act like aU other chemical substances 
 that produce reductions or decompositions. Thus, if 
 we add a solution of iodide of potassium to another of 
 bichloride of mercury, a color, a beautiful scarlet color, 
 starts out from the previously transparent and colorless 
 fluids; we have no power, no knowledge whatever, that 
 will enable us to tell a priori, the result of the admixture 
 of two unknown solutions simply fi-om their appearances, 
 but if we know the solutions we do know with accu- 
 racy the result of such an admixture, because this re- 
 sult is simply that derived from previous experimenta- 
 tion. But, notwithstanding a very extensive accumu- 
 lation of facts, we are still in utter ignorance, and 
 probably shall for ever remain so, as to the true 
 cause of chemical action; why, for instance, the salts of 
 the protoxide of iron are green, whilst those of the 
 peroxide are red; why hydrosulphuric acid produces, 
 yellow precipitates with a salt of cadmium or of 
 arsenic, an orange-red precipitates with antimony, and 
 a black one with so many of the salts of other metals. 
 
THE PHOTOGEAPHEr's GUIDE. 
 
 63 
 
 "We do not know what the precise action is; be it 
 tlie result of electricity, of light, of heat, of gravity, 
 which institutes some physical change in the ultimate 
 atoms or molecules that constitute the new compound. 
 And just as ignorant are we, for the experiments are 
 very similar, of the rationale of the development of 
 the latent photographic image. "We know simply that 
 a protosalt of iron, as well as other chemical substan- 
 ces, has the property of reducing the salts of silver 
 and of gold to the metallic state, and that, if the pro- 
 tosalt contain at the same time some organic material 
 in admixture, the reduction will be complex, partly 
 reguline and partly a compound; and we know fur- 
 thermore, or suppose, at least, that light institutes 
 some pecuHar physical changes in the silver solutions, 
 whereby they become predisposed to undergo this re- 
 duction on the application of the reducing agent. 
 This is the extent of our theoretic knowledge at 
 present. Here we stop on this subject, and proceed 
 at once to the mode of developing a negative. 
 Prepare in the first place the following solution : 
 
 DEVELOPER. 
 
 Protosulphate of iron - - - 1 ounce. 
 
 Eain water 16 ounces. 
 
 Acetic acid - - - - - 3 " 
 
 Alcohol - - - - - H " 
 Pulverize the salt, mix it intimately with the liquids 
 until dissolved, then filter and preserve in a stoppered 
 bottle for use. 
 
 We give the above formula in preference to any of 
 the more modern formulas which contain more or less 
 
64 
 
 THE PHOTOGEAPHEB's GUIDE. 
 
 of gelatine, which is twofold in its action: it modifies 
 the color of the developed image and acts at the same 
 time like an acid in restraining the development. 
 
 The developer being poured upon the plate carefully 
 and quickly so as to cover the whole of its surface al- 
 most instantaneously, and stiU retaining whatever 
 silver solution may have remained on its surface, you 
 keep the plate in motion so as to mix up the developer 
 thoroughly and to cover every part of the collodion 
 film. If the picture starts out almost at once, the plate 
 has been exposed too long; on the contrary, if a min- 
 ute or haK a minute expires before any change is pro- 
 duced on the film, the exposure has been too short. If 
 the change, of which we speak, begins the moment the 
 developer comes in contact vrith the collodion, and 
 continues slowly but distinctly, the exposure has been 
 about right. 
 
 The great art of development is twofold : it consists 
 in knowing when to stop, and to stop in aU cases be- 
 fore or as soon as fogging commences. Fogging is the 
 reduction of the silver solution into the reguline con- 
 dition even where light has not acted, thus producing 
 a veil on the parts that ought to be transparent. It 
 will frequently take place when all the solutions are 
 freshly prepared. Any saccharine or gelatinous sub- 
 stance mixed with these solutions, that is, with either 
 the silver bath or the developer, has a tendency to pre- 
 vent the silver from being reduced in those parts upon 
 which Hght has not acted. Acids have also the same 
 effect ; it is on this account that acetic acid is found in 
 the developer, and nitric acid in the silver solution. 
 Much of the troublesome effects of fogging, too, may 
 
THE PHOTOGEAPHEB's GUIDE. 
 
 65 
 
 be avoided by understanding the extent to which the 
 plate may be sensitized, and also by covering the plate 
 with a substratum of albumen as recommended in a 
 previous chapter. 
 
 For instance, as an experiment, drop a little of the 
 bath solution upon a plain glass surface, and add to it 
 a little of the developer, the experiment being per- 
 formed in the dark room ; reguline sUver soon begins 
 to make its appearance on the surface of the glass, and 
 thus to destroy its transparency. This is an example 
 of pure fogging. But if the glass has been previously 
 albumenized, the same amount of foggiag will not take 
 place, the albumen prevents the silver reduction, or at 
 least restrains it. You see then one of the benefits of 
 coating the plates with albumen previously to coatiag 
 them with coUodion. 
 
 It would appear from this circumstance that the 
 naked glass surface has a tendency to institute the 
 silver reduction, the moment the developer comes in 
 contact with it ; and hence it may be inferred, that if 
 we can prevent the solutions from coming in contact 
 with the glass surface, we shall at the same time 
 restrain reduction and consequently fogging. This 
 analysis of the subject teaches us how long to sensitize 
 the plate. As soon as the collodionized plate is im- 
 mersed in the bath the nitrate of silver solution begins 
 to permeate the collodion film, and at the same time 
 to produce by double decomposition the iodide and 
 bromide of silver on the surface and in the substance 
 of the collodion. This decomposition is made mani- 
 fest to the eye by gradual whitening of the film. Nat- 
 urally the front surface of the collodion film becomes 
 
66 
 
 THE PHOTOGBAPHER's GUIDE. 
 
 first wliite, then the middle, and finally the whole film 
 to the glass is of a cream-white. But by a careful ob- 
 servation you may hit upon the exact time when the 
 outer or front surface of the collodion film is cream- 
 like in color, whilst the back surface, or the surface 
 which is next the glass is of a slight bluish tinge. This 
 indicates that the silver solution has just permeated 
 the film as far as the glass. Now is the time to take 
 the plate out of the bath and to expose it ; that is, to 
 expose it before all the soluble iodides and bromides 
 are decomposed. These lie between the free nitrate of 
 silver and the surface of glass, and thus prevent or re- 
 strain the reduction of the sUver salt into pure silver; 
 they prevent fogging. But should fogging take place 
 before the picture is thoroughly developed, or, at 
 least, before the shadows are sufficiently opaque, your 
 best plan will be to wash the plate immediately and 
 then to fix the image and deepen the intensity after- 
 ward by what is called redevelopment or intensification. 
 
 Another method of proceeding in such a case con- 
 sists in washing the plate thoroughly, then in pouring 
 over it a dilute solution of either bromide or iodide of 
 potassium, and allowing it to remain on the surface a 
 short time. Naturally such a solution decomposes aU 
 free nitrate of silver in the collodion film., and free ni- 
 trate of silver is the main condition of fogging. Now 
 this being removed, wash the plate again, and pour the 
 developer again upon the plate and watch proceedings. 
 Gradually all the detail of the picture is brought out, 
 and the picture apparently is complete, regarded simply 
 as a picture, but the hghts, shades, and middle tones 
 are all there in regular gradation; but as a photogra- 
 
THE PHOTOGBAPHEr's GUIDE. 
 
 67 
 
 pliic negative it is yet incomplete; the opaque or dark 
 parts are not yet sufficiently dense. Hold up the ne- 
 gative and place your fingers between the negative and 
 the light ; if they are distinctly visible through the 
 shadows of the negative, the latter are not yet dense 
 enough. You must proceed with the development. 
 Previously pour off the old developer, wash the film 
 and then flow it quickly with the following solution : 
 Nitrate of silver - - - - 36 grains. 
 Bain water _ - - - 3 ounces. 
 Pour away all excess of the silver solution from one 
 corner, and then cover the film with fresh developer. 
 This proceeding will seldom fail to make the shadows 
 sufficiently opaque for the printing operation. Take 
 the plate out to the light, hold it up to a tree, and see 
 if the leaves are visible through the dense shades; if 
 not, the development has proceeded far enough. The 
 plate may now be thoroughly washed and immersed in 
 the fixing bath. 
 
 But should it happen that the development cannot 
 be carried on to its completion without fogging being 
 the result, wash the film and fix the image, which is 
 supposed in other respects to be perfect, and is only 
 lacking in intensity. 
 
 FIXIKG SOLUTION. 
 
 Cyanide of potassium - - 4 drachms. 
 
 "Water ----- 10 ounces. 
 Pour the solution over the plate and keep it in motion; 
 the yellow and cream-like parts will soon become trans- 
 parent, and the picture will now appear much more 
 beautiful than before. As soon as all the unaltered 
 
G8 
 
 THE PHOTOGEAPHEb's GUIDE. 
 
 iodides and bromides have been dissolved by the fixing 
 sokition, wash the plate on both sides and until every 
 trace of the cyanide has been removed. 
 
 This washing, like all the preceding operations of 
 the same natme, may be performed at a jet of water 
 issuing from a tap at the end of a water-pipe inserted 
 in a barrel, or being the termination of the ingress of 
 water from the public water works. There is no danger 
 of the collodion film being torn off the plate by means 
 of the current of water if the sm-face of the plate has 
 been previously albumenized ; but the fihn may easily 
 sHde off, if there has been no substratum, by the ma- 
 nipulations of a novice, but not so in the hands of an 
 experienced operator. Of course your aim will be to 
 learn by experience and finally to become perfect in 
 this beautiful art. 
 
 INTENSIFICATION AND TONING OF THE IMAGE. 
 
 Supposing that the picture possesses all the detail 
 and gradations required, but that the shades are not 
 sufficiently dense, you may flow the plate whilst the 
 film is stiU moist with the following solution : 
 Terchloride of gold - - - 2 grains. 
 
 Water 4. ounces. 
 
 Whilst the negative is stiU moist pour a sufficient 
 quantity of the above solution over the film as to cover 
 it quickly ; the tone will change very rapidly becoming 
 more of a blue-black ; if kept on, however, too long a 
 retrograde action sets in, and the tone gradually be- 
 comes fainter. Watch the opportunity when the whole 
 picture has assumed its first bright blue-black tone; 
 then pour the excess of gold solution back again into 
 
THE photographer's GUIDE. 
 
 69 
 
 the stock bottle. This solution soon becomes ex- 
 hausted, which is easily known by the disappearance 
 of the yellow color of the terchloride, and must then 
 be replenished with some fresh salt. The double salt 
 of gold and sodium, or gold and potassium is weU 
 adapted, but not that of gold and hme. 
 
 Wash the negative and place it upon a leveling- 
 stand with water on its surface. 
 
 The following stock solution is next required : 
 Fill a four ounce vial with rain water and throw into 
 it an ounce or more of bichloride of mercury, shake 
 the mixture well and set it aside to dissolve ; take care 
 to keep at the bottom of the bottle some of the un- 
 dissolved salt, by which you recognize that the solution 
 is concentrated. Label the bottle : Concentrated Stock 
 Solution of Bichloride of Mercury. Place side by side 
 with this a bottle of acetic acid. These two stock so- 
 lutions are required to make the following mixture for 
 present use : 
 
 Concentrated solution of bichlo- 
 ride of mercury - - - 1 drachm. 
 Acetic acid - - - - 1 " 
 Water - - - - - 6 drachms. 
 
 This mixture is now poured upon the moist plate; 
 hold the latter in such a position as to let the Hght 
 pass through it from beneath; you can then easily ob- 
 serve the gradual darkening of the film, and stop the 
 action when the intensity is satisfactory. By this 
 means you can get any amount of opacity in the 
 shades, and the tone of the negative is very pleasing 
 to behold. 
 
 3* 
 
70 
 
 THE PHOTOGBAPHEe's GUIDE. 
 
 Tlie only disadvantage it possesses, is the expense of 
 tlie gold solution; after all, this is a subordinate con- 
 sideration, as long as the work is good. Should the 
 expense be an objection to the above intensifying pro- 
 cess, we give the following which we formerly prac- 
 ticed and have found quite reliable. Make the follow- 
 ing stock solution: 
 
 TINCTURE OF IODINE. 
 
 Stock Solution. 
 
 Iodine 40 grains. 
 
 Alcohol 1 ounce. 
 
 SOLUTION OF IODINE FOR PRESENT USE. 
 
 Of the stock solution - - 10 minims. 
 
 Water 1 ounce. 
 
 "Where it is convenient, take the moist negative and, 
 holding it where the sim can shine upon it, pour a 
 sufficient quantity of the Present use solution all over 
 the film, and oscillate the plate so as to keep the solu- 
 tion in motion. The tone of the negative will soon as- 
 sume a faint rose color, whilst the solution itself has 
 gradually lost all its color, the iodine having been 
 taken up by the silver in the shades of the picture. It 
 is better to have the Present use solution quite dilute 
 in order that the deposit may be free from granulation. 
 Wash the plate and place it on the levehng-stand. 
 Prepare the two following stock solutions : 
 
 STOCK SOLUTION OF PYROGALLIC ACID. 
 
 PyrogalHc acid - - - - 24 grains. 
 Acetic acid - - - _ 2 ounces. 
 
THE PHOTOGEAPHEr's GUIDE. 
 
 71 
 
 STOCK SOLUTION OF NITRATE OE SILVER. 
 
 Nitrate of silver - - - 60 grains. 
 
 Rain water - - - - 2 ounces. 
 Now take of the first solution haK a draclim, water four 
 drachms, and mix with this solution two or three di'ops 
 of the solution of nitrate of silver. Add as little silver 
 as possible, as long as the solution graduaUy increases 
 the opacity of the shades, when poured upon the ne- 
 gative ; for a rapid action can easily be instituted, 
 but the deposit wiU be pulverulent and gritty. The 
 slower the action, the more uniform and smooth 
 the film becomes. As soon as the proper amount of 
 intensity has thus been obtained, the negative is very 
 thoroughly washed and then placed on the leveling- 
 stand for the subsequent operations. 
 
CHAPTEE Vm. 
 
 TO VARNISH NEGATIVES, AND TO PBEPAKE NEGATIVES FOR THE 
 SOLAR CAMERA, AND FOR COPYING WITH THE CAMERA. 
 
 We have now described the method by which a good 
 negative can be prepared for the ordinary printing 
 operations upon paper. The only thing that now re- 
 mains to be done with this negative, is to coat it with 
 some varnish or other preservative material, by which 
 the film is protected from injury in the subsequent 
 manipulations. Most of the varnishes in the market 
 become tacky when exposed to the direct rays of the 
 sun during the hot days of Summer; the paper then 
 adheres to the collodion film in patches, and tears them 
 off when it is removed from the plate. But a fihn of 
 albumen is free from this trouble, and we recommend 
 it as a very practical and rehable mode of coating 
 negatives. A single coating in general is sufficient; 
 but two coatings are better. 
 
 Separate the whites from a number of eggs, and 
 beat them up well. Then make the foUowing mix- 
 ture : 
 
 The white of egg, weU beaten - 10 ounces. 
 Distilled, or pm^e rain water - 5 " 
 Ammonia 1 drachm. 
 
 Pour a sufficient quantity of this solution upon the moist 
 film of the negative, so as to cover it completely; remove 
 any particle of dust or other concrete substance by means 
 
THE PHOTOGRAPHEe's GUIDE. 
 
 73 
 
 of a corner of a piece of paper, and then allow tlie excess 
 of albumen to drain off. The plate is now put away 
 on the drying-rack to dry. When dry the film may be 
 coated a second time, if this operation be deemed ne- 
 cessary, taking care to pour the albumen upon the end 
 of the plate opposite to that on which it was poured 
 the first time, and to place the plate on the drying-rack, 
 also, in an inverted position. 
 
 The albumen solution, above prescribed, will keep 
 for an indefinite time. 
 
 VAENISH FOR NEGATr^ES. 
 
 Some may object to this mode of protecting the col- 
 lodion film, and prefer keeping to the old system of 
 coating the film with varnish; we, therefore, give a 
 single formula for preparing a suitable varnish for the 
 purpose. 
 
 VARNISH TO BE USED ON THE COLD DRY PLATE. 
 
 G-um sandarac - - - - 2 ounces. 
 
 Oil of lavender - - - - 1 " 
 
 Alcohol 14 " 
 
 Chloroform _ _ - - 3 drachms. 
 
 Allow the materials to digest in a warm place; when 
 the gum is dissolved, the clear portion may be decanted 
 oflf for use when required. 
 
 This varnish is poured upon the negative in the same 
 manner as collodion, the excess being allowed to drain 
 back into the stock bottle ; remove all particles of dust, 
 and then rear the negative away on the drying-rack to 
 dry. 
 
74 
 
 THE PHOTOGRAPHEE's GUIDE. 
 
 The negative is now complete and ready to be hand- 
 ed over to the printer; but before we proceed to give 
 instructions about printing, it is our duty to describe 
 how to prepare negatives suitable for camera printing 
 or printing with the solar camera; this sort of print- 
 ing is quite distinct from what is denominated contact 
 printing, and requires a negative considerably differ- 
 ent from that which we have just described. 
 
 SOLAR CAMERA NEGATFV^E. 
 
 Take the thinnest plate glass compatible with the 
 manipulations which it has to undergo ; coat it as usual 
 with a very thin film of albumen, taking, for in- 
 stance, one ounce of the stock albumen solution 
 as given in this chapter, and diluting it with eight 
 ounces of water. Filter the solution. Be exceedingly 
 careful to get an even film, perfectly free from the 
 slightest particle of dust or insoluble material. Put 
 the plate away to dry in a clean place where there is 
 no dust stirring. 
 
 COLLODION EOR A SOLAR CAMERA NEGATIVE. 
 
 Take the coUodion as prepared by one of the 
 preceding formulas according as it is for in door 
 or out door work, and dilute it in the following man- 
 ner: 
 
 Bromo-iodized collodion - - 1 ounce. 
 Alcohol - - - - - 4 drachms. 
 Ether - - - - - 4 drachms. 
 
 This collodion, of course, will be very thin and can 
 be flowed over the plate without producing the slight- 
 est reticulation. 
 
THE PHOTOGRAPHEb's GUIDE. 
 
 75 
 
 The film is sensitized in the usual way and in the 
 ordinary silver bath in every day use. Expose the 
 plate somewhat longer than you would for a negative 
 for contact printing; that is, the exposure must be com- 
 plete; for an under-exposed plate is not to be thought 
 of in solar camera operations. 
 
 How are you to know when a plate is under-exposed 
 or over-exposed ? 
 
 Take, for instance, a picture of the trunk of a tree, 
 its branches and leaves. If the plate be under-exposed, 
 you will get no detail, none of those beautiful indenta- 
 tions, rough prominences and peculiar markings on the 
 bark, which are as characteristic of the tree as the dif- 
 ferent forms of wool and hair are to the animal; you 
 will obtain, also, none of the nerves and fibers that 
 distinguish the leaves. Your negative will present, de- 
 velop as long as you like, nothing but outlines of the 
 trunk, branches and leaves of the tree in the midst of 
 thick darkness — your negative is totally devoid of de- 
 tail. 
 
 An over-exposed plate, on the contrary, goes too 
 much in the opposite direction, and the development 
 is so rapid that the detail of the indentations, promin- 
 ences, markings, etc., becomes soon annihilated by 
 being clogged up with too much deposit, and all the 
 diversity of light and shade is finally indistinguishable; 
 the picture is one mass of fogginess, like a meadow 
 covered with mud after a freshet — it is all mud. 
 
 The middle way between these two extremes is the 
 one we take or strive to get into when we expose pro- 
 perly; but for our present purpose, it is better to 
 slightly over-expose than under-expose, because our 
 
76 
 
 THE PHOTOGEAPHEr's GUIDE. 
 
 object is to get all the detail rapidly, so as to preserve 
 the negative quite thin in the shades. 
 
 The same developer may be used as before recom- 
 mended, adding a drop of nitric acid to each ounce of 
 the developer. As soon as the picture is thoroughly 
 out in detail everywhere, wash the negative immediate- 
 ly, for a step further is always an injury to the work- 
 ing quahties of the plate; avoid making the shades 
 opaque. 
 
 Your negative, if right, will be a sort of phantom 
 negative, constructed upon gossamer, very thin, finely 
 delineated, and very beautiful. Wash it well, and put 
 it away on the drying-rack to dry. Negatives for the 
 solar camera must not be varnished; in fact, there is 
 no need of any varnish, for the film is not subjected to 
 any hard usage; but it must be kept thoroughly out of 
 the dust. 
 
 "Whilst developing and washing a negative it is ad- 
 visable to receive all the wash water in an appropriate 
 vessel beneath; from time to time a handful of salt is 
 thrown into the fluid at the bottom which converts the 
 soluble nitrate of silver of the washings into an insol- 
 uble powder, which will gradually accumulate at the 
 bottom. There wiU be in addition a quantity of pure 
 silver mixed with it, produced by the action of the 
 protosulphate of iron on the free nitrate of silver on 
 each plate. At a distance of five or six inches from the 
 bottom of the vessel there is an outlet pipe into the 
 sink which carries away all excess of fluid. This pipe 
 can be opened and closed at will by means of a stop- 
 cock. It is well to keep it closed during the operation 
 of development; that is, in the daytime in order to al- 
 
THE PHOTOGEAPHEe's GUIDE, 
 
 77 
 
 low the requisite decompositions to be effected by tlie 
 salt solution, as also during the night in order that the 
 insoluble chloride of silver and the reduced silver may- 
 settle to the bottom. Early in the morning and before 
 operations commence the stop-cock is then opened and 
 the surplus water is allowed to flow away. The pipe 
 is again closed, and a Uttle more fresh salt is thrown 
 into the vessel. If you are doing an extensive busi- 
 ness you will be surprised how much silver you have 
 thus saved by the end of the year. 
 
 Negatives for making transparent positives, such as 
 glass stereographs, which are so universally and deser- 
 vedly admired, and negatives for making opal or por- 
 celain pictures by means of the copying camera, are all 
 prepared in the same way as those for the solar cam- 
 era. You may, it is true, obtain positives from your 
 ordinary negatives, but they will be far from satisfac- 
 tory; they will in general be mere black and white 
 daubs; there will be no, or seldom any, detail. 
 
 We apply this mode of preparing negatives for copy- 
 ing purposes to the preparation of transparent posi- 
 tives for producing enlarged negatives. Thus, for in- 
 stance, a properly prepared quarter-sized negative of 
 some choice landscape, taken on the spot with the di- 
 lute collodion, is placed in the copying camera, and a 
 plate coated with dilute collodion is placed at the op- 
 posite end of this camera to receive the impression, 
 which, of course, will be a transpare:nt positive. Fol- 
 low the rules above given and give rather more than 
 the full exposure and stop the development the mo- 
 ment all detail is visible. "Wash and fix with cyanide 
 of potassium in the usual way. Finally, wash thor- 
 
78 
 
 THE PHOTOGEAPHEr's GUIDE. 
 
 OTighly and dry the positive. This positive, if carefully 
 prepared, will be sharp, semi-transparent, bright look- 
 ing, and full of all the minute delineations of the orig- 
 inal from which the negative was taten, and, if also 
 carefully preserved, will be the nucleus or model from 
 which any amount of negatives may subsequently be 
 taken, of the same size or of any given size required. 
 There is no branch of photography that tests the skill 
 of the operator, and the perfection of the lens more 
 than this sort of reduplication; but, at the same time, 
 there is none which is more interesting and remuner- 
 ative. 
 
 Suppose now we wish a negative of the landscape 
 above mentioned and of which we took a quarter-sized 
 negative for copying purposes; aU we have to do is 
 place the small transparent positive in the copying 
 camera and to arrange the conjugate foci by means of 
 the two sliding bellows so that the picture on the 
 ground glass is of the size required. A globe lens, or 
 one of Dallmeyer's lenses, is the most appropriate for 
 the purpose. If you wish a negative for ordinary 
 printing operations, you must use the undiluted collo- 
 dion and pursue the common routine of development. 
 You can, we maintain, in this way get an enlarged ne- 
 gative as good as if you were to take an original ne- 
 gative of this size on the spot; in fact, it is possible, 
 you may get a superior negative, because of the troubles 
 always arising out of the transportation of a tent, etc., 
 for work of this size. 
 
 Before we leave this subject of the wet negative and 
 its development, we may put in a few remarks about 
 the fixing solutions. In many large establishments 
 
THE photographer's GUIDE. 
 
 79 
 
 the negative is fixed in a solution of hyposulphite of 
 soda, and a large bath, holding two or three gallons of 
 the fluid, is always kept in readiness. 
 
 FIXING SOLUTION WITH HYPOSULPHITE OF SODA. 
 
 Hyposulphite of soda - - - 2 lb. 
 Rain water - _ _ - 2 gallons. 
 
 Fresh hyposulphite can be added to the bath every two 
 or three days; and it will be well to filter the solution 
 at least once a week, and at the same time to collect 
 the deposit, which is a sulphide of silver, as a separate 
 silver residue for reduction. This bath is very con- 
 venient in a gallery, for the negative can be left in it 
 for a long time without being materially injured; but 
 from our experience both in opal printing by the wet 
 process, as well as in the fixing of dry plates, we are 
 convinced that an old and much used fixing solution is 
 frequently the cause of much fogging and stains on the 
 plate, and we therefore prefer a fresh solution for each 
 plate ; and we furthermore prefer fixing with cyanide 
 of potassium, to fixing with hyposulphite of soda, al- 
 though the former is a very poisonous material and 
 acts with so much energy as to obliterate the picture 
 itself, unless great care be employed in its use. The 
 poisonous effects can be entirely avoided by using the 
 pneumatic holder for developing and fixing, etc., the 
 plate; and a quick eye can designate the exact moment 
 when to stop the fixing; the operation is quick and 
 effectual. 
 
 Pyrogallic acid is also used sometimes for develop- 
 ing the image; it is an excellent developer and pro- 
 duces a very beautiful picture, but its action is not so 
 
80 
 
 THE PHOTOGEAPHEk's GUIDE. 
 
 rapid as the iron developer. The deposit on the plate 
 is of a different nature from that produced by the iron 
 salt, being a compound silver salt containing organic 
 matter, whilst that from the iron solution is mostly re- 
 duced silver. The exposure must be longer with py- 
 rogaUic acid than with the iron salt. 
 
 PYEOGALLIC ACID DEVELOPEB. 
 
 PyrogaUic acid - - - 12 to 18 grains. 
 
 Acetic acid - - _ _ i ounce. 
 
 Water 7 ounces. 
 
 In Winter as much as eighteen grains may be used 
 to the ounce of acetic acid, whilst in Summer twelve 
 grains will be found quite sufficient. 
 
 We cannot leave this subject without adverting to 
 the excellent developer with gelatine and protosulphate 
 of iron, the discovery of M. Carey Lea, Esq., to whom 
 we are indebted for so much that is valuable in photo- 
 graphy. His formula is as follows : 
 
 COLLO-PBOTOSULPHATE OF lEON DEVELOPEB. 
 
 " Add an ounce of sulphuric acid to three ounces of 
 water, and set aside to cool. Then add to this Hquid 
 an ounce of good gelatine; let it swell and dissolve, 
 placing it for that purpose in a shghtly warm place, 
 not exceeding blood heat, for twenty-four hours. Then 
 add iron filings in excess, avoiding all application of 
 heat; let it stand for several days. Finally, add half a 
 drachm of acetate of soda and filter. Dilute the solu- 
 tion to fifteen ounces." 
 
 Many modifications have been made of this formula 
 but with very sHght emendations, if any. With a 
 proper length of exposure the picture can be developed 
 
THE photographer's GUIDE. 
 
 81 
 
 to the requisite intensity without any other aid. If 
 photographers were patient chemical manipulators 
 they would always use this developer or some modifi- 
 cation of it; we ourselves never think of using any 
 other, and yet we have not recommended it as the de- 
 veloper proper for the operator, because — because he 
 would blunder somewhere in its preparation, fail to get 
 good results, and condemn both us and the ferro-gela- 
 tine developer to the abode of Hades, Uterally, the 
 Kingdom of Darkness. 
 
CHAPTER IX. 
 
 THE PEINT HOW TO MAKE IT. 
 
 The operator might as well pick rags, tear them into 
 jGibers, make them into pulp and finally convert them 
 into paper, as to put himself to the trouble of prepar- 
 ing his own albumen paper. This is now a business of 
 itself, and it is fortunate that it is so; for it is quite a 
 bore and an expense to prepare any chemical or me- 
 chanical article in small quantities for home consump- 
 tion. 
 
 Nevertheless, we will tell our readers how the paper 
 may be prepared. The paper suitable for photogra- 
 phic purposes must be quite uniform in texture, 
 smooth on the surface, perfectly white, free from all 
 metallic salts, and as far as possible impermeable to 
 fluids. It is to be hoped our paper manufacturers will 
 experiment to a greater extent than they have done, 
 so as to attain to this impermeability without at the 
 same time impairing the flexibility of the paper. The 
 requisite paper being on hand, the next thing is to 
 sensitize it for photographic purposes. The ordinary 
 process consists in mixing the chemical ingredients 
 with a solution of albumen, and then to let the sheets 
 of paper float on this solution for about three minutes, 
 after which they are taken out and hung up to dry. 
 
 If we had to prepare photographic paper, we would 
 do it in the following manner : 
 
 The paper should first be floated on a solution of 
 
THE PHOTOGEAPHEe's GUIDE. 
 
 83 
 
 gelatine of the proper consistence, hung up and dried. 
 
 Secondly, each sheet should be passed between a 
 pair of rollers, on a highly polished plate of steel, in 
 order to fill up the pores of the paper with the gelatine. 
 
 Thirdly, let each sheet float about three minutes on 
 a solution of alum which converts the gelatine into a 
 sort of leather, rendering it insoluble, and, to a much 
 greater extent than before, impermeable to fluids. 
 
 These three operations are quite preparatory to the 
 really photographic part of the business. The sheets 
 when dry are now ready to be floated on the prepared 
 albumen. 
 
 Take the whites of any number of fresh eggs and 
 beat them up for a long time, that is for an hour or 
 two so as to disintegrate the substance, and break up 
 its adhesion. Allow the albumen to settle. Then pre- 
 pare a mixture according to the following formula : 
 
 Clear albumen - - - 20 ounces. 
 
 Distilled water - - _ 6 " 
 
 Ammonia - - _ _ 2 drachms. 
 
 Chloride of ammonium - - 6 " 
 
 Instead of the chloride of ammonium, the same 
 amount of chloride of sodium, or of the chloride of 
 barium may be used. Beat the solution again well to- 
 gether, or shake it well up in a bottle ; after subsidence 
 the clear portion is poured into a large flat bath. The 
 paper, prepared as above directed, are floated on the 
 gelatine side next to the albumen; each is left for three 
 minutes on this solution, taking care previously to 
 break up all bubbles with a glass rod. The sheets are 
 then taken out and hung up to dry in a room quite 
 
84 
 
 THE PHOTOGBAPHEr's GUIDE. 
 
 free from dust. "When dry, two sheets placed back to 
 back are put between two highly polished plates of 
 steel and passed between rollers, and then packed away 
 for sale or use. 
 
 The film of albumen contains a soluble chloride, 
 which, when it comes in contact with nitrate of silver, 
 is converted into chloride of silver, a salt which is very 
 sensitive to Hght. 
 
 Albumen paper must be kept in a dry place, other- 
 wise it is liable to change. The different tones in 
 samples of albumen paper manufactured by different 
 houses, arises in a great measure from the chloride 
 which is used; thus, chloride of ammonium communi- 
 cates to the print, when it leaves the printing-frame a 
 reddish tone, whilst the salt of sodium or of barium 
 inclines more to the black. This difference of color, 
 however, in the original print, is not of material con- 
 sequence, since, by toning afterward in the gold solu- 
 tion, the final hue is the same or nearly the same, 
 whatever chloride w^as used in the preparation of the 
 paper. 
 
 SENSITIZING OF ALBUMEN PAPER. 
 
 The soluble chloride in the albumen paper must fii'st 
 be changed into the insoluble chloride of silver, before 
 the paper is ready for receiving any impression from 
 Light. For this purpose we agaia require, as in the 
 preparation of the negative, a silver bath. The vessel 
 which contains the silver solution is a flat dish of pho- 
 tographic ware, porcelain, glass, or varnished wood. 
 Large porcelain dishes are made on purpose to receive 
 the silver solution; but owing to the expense some 
 
THE PHOTOGEAPHEK's GUIDE. 
 
 85 
 
 photograpliers construct wooden dishes of thin dry 
 wood, which answer the purpose quite well. Along 
 the edges they pour a melted solution of wax and resin, 
 or a solution of seahng wax or lac in alcohol. The 
 latter solution is the better of the two and is easily 
 made. A proper quantity of seahng wax is broken up 
 into pieces, and put into a teacup containing alcohol; 
 the cup is then placed on the stove and stirred about 
 untH the solution is made. A proper quantity of this 
 solution is poured along the edges and seams, and is 
 rubbed quickly in by means of a brush. This cement 
 soon dries. The solution may afterward be consider- 
 ably diluted and used as a final varnish to the inside 
 and outside. The inside wiU require two or three 
 coats of varnish in order to render the wood water- 
 tight. 
 
 SENSITIZING SOLUTION. 
 
 Nitrate of silver - - - - 2 ounces. 
 
 Water 14 " 
 
 Alcohol 1 " 
 
 This bath contains about sixty grains of nitrate of 
 silver to the ounce of the solution. The intention of 
 the alcohol is to prevent blistering in the albumen 
 film, and consequently where there is no such tendency 
 the alcohol may be omitted. A small quantity (about 
 a drachm) can be added to the bath every time you 
 are about to sensitize a fresh quantity of paper; at the 
 same time you may also add a drachm or two of crys- 
 tals of nitrate of silver. This bath is placed in the 
 non-actinic room in a convenient position near a 
 wooden partition; near the bath and along the parti- 
 tion an inclined gutter is constructed of well varnished 
 4 
 
86 
 
 THE PHOTOGRAPHEK's GUIDE. 
 
 tin plate, and so placed as to allow any fluid that drops 
 into it to drain into the silver bath. 
 
 The sheets of albumen paper are sensitized in the 
 following manner : The four corners of each sheet are, 
 bent from the albumen side back to the extent of half 
 an inch, thus forming four vertical projections, by 
 which the sheet can be seized by two opposite corners 
 diagonally. When so held, and the hands are brought 
 shghtly nearer together than the width between the 
 two corners, it is evident the middle parts of the sheet 
 will hang down. The albumen surface is below and is 
 convex. In this position the sheet is lowered upon 
 the silver solution, which has just previously been fil- 
 tered, the middle part thus coming into contact with 
 the fluid first, the two sides are gradually let down, 
 until the whole sheet lies flat upon the solution. By 
 this means you avoid the production of bubbles. Still 
 it is always better to be quite certain as to this head; 
 raise each corner, therefore, separately by one of the 
 four ears, and examine the parts for bubbles; if there 
 are any they must be broken up by means of a glass 
 rod kept close by for the purpose. If the paper is apt 
 to cockle or refuse to he down upon the solution, 
 breathe upon the back part, it wiU immediately yield 
 to the impression of the moist breath and fall down. 
 As soon as the sheet is all right and every where in 
 contact with the nitrate of silver, you may allow it to 
 remain for one minute; after which you raise one of 
 the corners by means of a piece of strong silver wire, 
 and then lift the sheet gradually up from the fluid, and 
 you then pin it or otherwise attach it by clamps to the 
 wooden partition behind, and just so high as to allow 
 
THE PHOTOGEAPHEr's GUIDE. 
 
 87 
 
 the lowest diagonal corner to drain into the bath 
 which lies close to the partition. When the sheet is 
 large or of the full size, it is well to pin the two upper 
 cprners and one of the lower corners to the partition, 
 but still so that the sheet hangs as it would do, if sup- 
 ported only by one corner. The lowest corner is not 
 pinned, but dips over the side of the bath. 
 
 Another sheet is now placed upon the sensitizing so- 
 lution in the same way; and the excess of silver solu- 
 tion from the first sheet having drained off by this 
 time, this sheet is now transferred to another position 
 on the partition, where the lowest corner can just hang 
 over the gutter at its farthest extremity. Here it is 
 left to dry completely. The second sheet takes its 
 place after draining, as before, next in order to the 
 first; and so you proceed to the last sheet. If a drop 
 of silver solution stiU adheres to the lowest corner of 
 each sheet, remove it with a bit of blotting paper. 
 
 Old filtering paper, through which solutions of silver 
 have passed, pieces of blotting paper used for this pur- 
 pose above mentioned, spoiled sheets of sensitized 
 paper, clippings of prints, in fine, any paper whatever 
 which contains stains of silver, have to be jDreserved in 
 a large chest or barrel kept for the purpose; in a 
 short time we will tell you what to do with them. 
 
 As soon as you have done sensitizing the paper for 
 the day, empty the silver solution into the stock bottle. 
 At the bottom of this bottle we always keep a layer of 
 chloride of silver, and the stock bottle itself retains its 
 position in the dark-room. The chloride of silver is 
 obtained from an old silver bath by throwing into it a 
 solution of common salt, as long as any white precipi- 
 
88 
 
 THE PHOTOGEAPHEe's GUIDE. 
 
 tate is produced. Tlie vessel is then set aside for an 
 hour or so in the dark-room, after which the super- 
 natant solution is easily separated by decantation from 
 the residue beneath. After which the chloride is 
 washed with pure water by shaking and again allowed 
 to subside; the operation of decantation and washing 
 is performed twice; all the water is finally poured off 
 and the sensitizing solution may then be poured upon 
 it and kept there until again required for use. 
 
 The object in view by keeping the silver solution in 
 contact with chloride of silver is to keep the sensitizing 
 fluid always colorless, a method which has answered 
 our purpose exceedingly well. When the chloride it- 
 seK becomes colored, dry it and preserve it for reduc- 
 tion with other silver residues at the proper time. 
 
 When the sensitized sheets are perfectly dry, they 
 may b« submitted or not submitted to the fumes of 
 ammonia, just as you feel inclined about the matter. 
 The advantage of fuming is, after aU, not very great; 
 and the finished print is equally good whether the sen- 
 sitized paper was fumed or not. Paper that has been 
 fumed is probably more sensitive, and thus requires 
 less exposure. The simply sensitized paper, when dry, 
 may be preserved for some time without changing 
 color, or deteriorating; but if it has been once fumed 
 it soon becomes yellow ; the fuming, therefore, must 
 take place only a short time before the paper is re- 
 quired for printing. 
 
 rUMTNG OF SENSITIZED PAPEE. 
 
 This is a very simple operation. A large cupboard 
 may be made out of a drygood's box by placing it on 
 
THE PHOTOGEAPHEk's GUIDE. 
 
 89 
 
 one end and fixing it on a frame as high as the knees, 
 or about two feet high. The Hd is fixed on hinges so 
 as to open sidewise. The sheets of sensitized paper 
 are then fastened with a pin at each corner around the 
 three sides and on the door or Hd, as also on the up- 
 per end, taking care in every case that the albumen 
 film looks outward. At the bottom of the box a saucer 
 is placed; into this saucer, after it has been made 
 warm over the stove or a spirit lamp, a few drachms of 
 ammonia are poured; and the door is then closed. 
 The ammonia soon evaporates and comes intimately in 
 contact with the albumenized surface. In ten minutes 
 or a quarter of an hour, the door is opened and the 
 sheets are taken out and hung up to air in the dark 
 room, of course. They are then ready for use. 
 
 The printing operation. 
 
 There is a great variety of printing-frames in the 
 market ; and it is a difficult task to say which is the 
 best for general purposes. Some of them have special 
 advantages for vignetting which the others do not pos- 
 sess; and in this case there can be no difficulty in 
 making the appropriate selection. Since you will re- 
 quire a number of printing-frames, especially for card- 
 pictures, you will do weU to get one of each different 
 make and then select that which suits you best, before 
 you purchase a complete outfit. 
 
 The negative is placed in the printing-frame, collo- 
 dion side uppermost; the sensitive paper of the proper 
 size is then placed upon the negative, so that the col- 
 lodion film of the negative and the albumen film of the 
 paper lie in contact; over the paper comes a piece of 
 
90 
 
 THE PHOTOGRAPHEk's GUIDE. 
 
 soft cloth, either loose or attached to the spring back 
 which is pressed down tightly so as to keep the paper 
 in close apposition with the negative, and fixed there. 
 The printing-frame is then turned up and placed so 
 that the direct rays of the sun or diffused hght can 
 pass through the negative to the paper. 
 
 By means of the folding door at the back of the 
 frame you can, from time to time, examine the progress 
 of the actinic impression; this examination must take 
 place, however, in very subdued light, otherwise the 
 purity of the whites would be injured. Very soon the 
 picture will appear quite perfect as a picture, but it is 
 not yet perfect for the purposes intended; you must 
 over-print, print until the shades begin to be bronzed 
 by the action of the light, and the whites are no longer 
 quite white. The prints are then taken out and stored 
 away in a drawer or between the leaves of a book until 
 you have finished printing for the day or for the oc- 
 casion. 
 
 The next operation is performed in a very weak light 
 or in the non-actinic room. It consists in cutting the 
 prints to the proper size for mounting. For card-pic- 
 tures there are punches and machines that do the 
 work very effectually and quickly. The one made by 
 Wm. B. Holmes, Broadway, is excellent. If you have 
 neither a punch nor a machine, the next best is to cut 
 out a piece of glass of the required shape and size, and 
 then to grind the edges perfectly smooth and even. 
 You may then place this piece of glass on the print, 
 and holding them firmly together in the left hand, you 
 may easily clip the edges off with a pair of long scissors 
 
THE photographer's GUIDE. 
 
 91 
 
 iall round the glass; this is the easiest process next to 
 that with the machine. 
 
 Another method is to lay the print on a sheet of 
 plate glass, and to place the glass form over it ; you 
 may then proceed round the edges of the glass with a 
 sharp-pointed penknife and cut of the edges of the 
 paper as you proceed. For such work as this it is 
 well to have a table so constructed that the top can re- 
 volve on a pivot like a potter's table. So provided you 
 can easily keep your fingers firmly fixed on the glass 
 form and, at the same time, revolve the table so as to 
 bring each side of the glass into an easy position so as 
 to make the next incision in succession. 
 
 Similar glass forms are used for stereoscopic and 
 other prints of a small size ; but larger prints may be 
 cut out with a square to the size desired. 
 
 All the chppings are preserved in the chest or barrel 
 above mentioned. 
 
 We prefer cutting the prints out at this early stage, 
 because we save a large amount of gold in the toning 
 operation, by simply toning no more than is needed. 
 This is quite an important precaution, whose value you 
 wiU soon learn to recognize. 
 
 Let us now proceed to the next operation in succes- 
 sion. The cut prints are all thrown into a vessel of 
 pure rain, or well water, in which they are kept in 
 motion in order to facilitate the separation of aU the 
 free nitrate of silver; the sole object of the washing is 
 to do this. "Where the convenience exists, a stream of 
 running water is allowed to flow over them; but where 
 it does not exist, the prints are transferred to another 
 vessel of pure water, whilst the water in the first vessel 
 
92 
 
 THE photographer's GTHDE. 
 
 is allowed to enter by means of a pipe and tap into 
 another containing a solution of salt. The nitrate of 
 silver is thus converted into the insoluble chloride 
 where it is afterward collected either by filtration or 
 subsidence. The water from the second vessel, con- 
 taining the prints, also enters the one which contains 
 the solution of salt, in order to collect what little ni- 
 trate of silver may still have remained in the prints 
 after the first washing. After the prints have thus 
 been thoroughly washed, of course in the dark-room, 
 they are transferred to the toning bath, which is a 
 large flat dish sufficiently capacious to hold the ordin- 
 ary quantity printed in your establishment. 
 
 The toning solution consists essentially of the ter- 
 chloride of gold; all other substances are secondary in 
 importance; and the terchloride of gold is an article 
 which you can seldom obtain in a pure form, or in an 
 invariable form. It is sold in general as a double salt, 
 either the double chloride of gold and sodium, of gold 
 and potassium, or of gold and calcium. If you deal 
 with only one photographic establishment, you may, 
 probably, always obtain the same sort of gold salt, and 
 thus produce in general the same uniform results every 
 time you have to tone. This is the only salt which it 
 is well for the photographer to prepare himself ; for 
 then he knows its composition. 
 
 TO PREPARE TEECBXORIDE OF GOLD. 
 
 Pure gold can be obtained from the mint ; and fre- 
 quently a sufficient quantity of pure scraps of gold can 
 be met with at the dentist's; in case of need the gold 
 coins of the country may be used ; they contain, how- 
 
THE photographer's GUIDE. 
 
 93 
 
 ever, an alloy which wiU detract in a trifling degree 
 from the purity of the salt thus obtained and from its 
 effects in toning. 
 
 Make a mixture of two ounces of hydrochloric acid 
 and one of nitric acid; this forms what is called aqua 
 regia, or royal water, from the fact that it is capable of 
 dissolving the noble metals gold and platinum, which 
 are insoluble in either acid alone. The truth is that 
 these metals are dissolved easily enough in chlorine, 
 and it is probably the chlorine, which is produced by the 
 mixture of the two acids, that performs the operation. 
 Place the mixed acids in an evaporating dish on a water 
 bath, and throw a quantity of pure gold leaf and scraps 
 into the mixture, and keep adding as long as they are 
 dissolved; finally, with some gold stiU remaining undis- 
 solved at the bottom of the vessel, evaporate the liquid 
 to dryness, or allow it to evaporate spontaneously to dry- 
 ness in a large wash-basin exposed to the sun's rays. 
 The solution must not be evaporated to dryness at a 
 temperature greater than that of boihng water, other- 
 wise the salt will be decomposed. As soon as the salt 
 has thus been made dry by either artificial or spon- 
 taneous evaporation, it is still an acid salt; that is, it 
 contains still a small quantity of free acid, which you 
 must decompose. Dissolve, therefore, the resulting 
 reddish colored salt in an ounce of water and add to 
 it powdered chalk as long as an effervescence is pro- 
 duced. As soon as this ceases, pour off the Liquid por- 
 tion from any undissolved carbonate of lime (chalk), 
 and evaporate it to dryness again on a water bath. 
 You have now got the double chloride of gold and 
 calcium ; and if you always prepare it by the way pre- 
 4* • ' ' 
 
94 
 
 THE PHOTOGRAPHEe's GUIDE. 
 
 scribed, it will always have the same uniform compo- 
 sition, from which you may reasonably expect to get 
 uniform results when toning. 
 
 PBEPARATION OF THE TONING BATH. 
 
 The double chloride of gold and 
 
 calcium ----- 4 grains. 
 
 Acetate of soda - - - - 80 " 
 
 "Water (one quart) - - - 32 ounces. 
 
 Alcohol _ - - - _ 1 ounce. 
 
 The bath is best when prepared the day before it is 
 required; but it may be used the moment it is made. 
 More gold may be added if needed, which you will 
 have to determine from the slowness of the action. 
 Warmth materially hastens the toning operation. 
 Eapid toning, however, is not to be recommended. 
 Keep the prints in motion, and turn them round from 
 time to time ; if they are allowed to rest in one place, 
 irregular patches of toning are apt to be formed, which 
 cannot be removed or equalized afterward. You will 
 gradually see the change in tone as it proceeds. As 
 soon as the color is a brilhant purple, and before the 
 slate blue sets in, remove each print into a vessel of 
 pure water, until the toning operation is complete. 
 You will naturally understand that the prints have to 
 be washed, toned, and fixed in the non-actinic room, 
 because, until they have been fixed, they are still sen- 
 sitive to the action of the light and thus liable to 
 change. 
 
 If you aim to get bright, brilliant, and uniformly well- 
 toned prints every time, it is advisable to prepare a 
 fresh toning |3ath for each operation of toning. You 
 
THE PHOTOGEAPHER's GUIDE. 
 
 95 
 
 will have, therefore, to learn by experience the quantity 
 of gold required for a given number of prints, and thus 
 to proportion the bath to the quantity of prints on hand. 
 After toning, the residual gold solution is poured into 
 a vessel for the purpose, containing a solution of the 
 protosulphate of iron, which reduces the gold out of 
 the solution in a pure metallic form; but the solution 
 contains in addition, nitrate of silver, so that the pre- 
 cipitate produced by the protosulphate of iron is a 
 mixture of gold and silver. When the precipitate has 
 settled, the hquid is allowed to filter off, and the vessel 
 is then again ready to receive the next supply. 
 
 After a time the sediment is taken out, thoroughly 
 washed in several waters, and then treated as follows : 
 Pour upon the sediment a sufficient quantity of dilute 
 nitric acid (half nitric acid and half water) so as to 
 cover it well; then heat the mixture to a boiHng tem- 
 perature and allow it to cool gradually. By this means 
 the silver is dissolved, but the gold remains unchanged. 
 Separate the fluid portion from the gold residue by 
 filtration, and wash the residue to remove every trace 
 of the nitrate of silver. Finally, evaporate the liquid 
 portion to the crystallizing point and set it aside to 
 crystallize, or evaporate it to dryness. The resulting 
 substance is either crystallized nitrate of silver, or the 
 silver salt in the amorphous condition, either of which 
 may be used for the preparation of the sepsitizing so- 
 lution for papa-r. The gold may. be dissoived again in 
 nitro-hydrochloric acid according to the method pre- 
 scribed, and is then ready- for. the preparation of the 
 toning solution. 
 
 The prints ar^ now stirred about in the water, and, 
 
96 
 
 THE photographer's GUIDE. 
 
 then transferred singly to the fixing bath which is 
 made as follows : 
 
 FIXING SOLUTION FOR PRINTS. 
 
 Hyposulphite of soda - - - 6 ounces. 
 Water (one quart) - - - 32 " 
 Alcohol . - . - _ 1 ounce. 
 
 This bath may be used over and over again ; but in 
 this case more salt must be added every time the bath 
 has to be used, and a Httle alcohol is also added. 
 Alcohol prevents the albumen from bhstering. It is 
 advisable, too, to filter the bath after every operation 
 of fixing ; the residue that remains on the filter is 
 chiefly the sulphide of silver, which must be preserved 
 separately from other silver residues, because it may be 
 reduced separately. 
 
 The prints are kept moving in the fixing solution for 
 about a quarter of an hour; the tone of the prints 
 generally change to a reddish hue when they are 
 placed in this bath, but it is again restored by the 
 time the fixing is complete; the white portions of the 
 paper, after the tone has been restored, will be quite 
 pure, not spotted or speckled, when viewed by trans- 
 mitted Hght. At this stage the prints are removed 
 from the fixing solutipp and placed in the washing- 
 tank. 
 
 CONSTRUCTJQN PI' THE WASHING-TANK. 
 
 It is supposed the operaitpr is furnished with water 
 from the water-works, or froiq a running stream. The 
 tank is cubical in shape like a large drygood's box ; 
 the water enters at the bottom. Along the edges at 
 the bottom there is a strip of wood fixed, two inches 
 
THE PHOTOGEAPHEb's GUIDE. 
 
 97 
 
 high and one inch thich; this forms a projecting ledge 
 all around; on this ledge a frame of wood, on which is 
 stretched an open sieve of hair or wire, rests. A num- 
 ber of prints are placed in a single layer on this sieve; 
 a second frame rests upon the first; and the sieve of 
 the second frame is also covered with prints; and thus 
 any number of frames are piled one over the other un- 
 til all the prints are placed in layers ready for wash- 
 ing. The uppermost frame is then firmly wedged in 
 its place to prevent the others from rising out of their 
 position. In addition there is a leaden tube bent into 
 the form of a syphon, one end dips into the tank and 
 reaches to within haK an inch of the bottom, the bend 
 passes through a hole in the side of the tank, which 
 is two inches from the top, and made watertight by 
 stuffing and cement. The other leg of the syphon is 
 conducted into the channel that carries away all the 
 refuse water of the establishment. The diameter 
 of this pipe is larger than that through which the 
 water enters, so that when the water reaches above the 
 lead of the syphon, the latter begins to work and the 
 water flows out of the tank faster than it enters; in a 
 short time the tank becomes quite empty, when the 
 syphon ceases to act until the tank is again filled. This 
 mode of washing pi*ints is very effectual, and after they 
 have remained half a day or over night subjected to 
 this operation, all the hyposulphite has been thor- 
 oughly removed from the prints, and then permanency 
 is thus assured. Prints that have been thus treated 
 manifest no change, no decay in the space of three 
 years, and we doubt not, they are, in the common ac- 
 ceptation of the term, quite permanent. 
 
98 
 
 THE PHOTOaRAPHEE's GUIDE. 
 
 THE DRYING-FRAME. 
 
 Construct a large rectangiilar frame, like that for a 
 swing looking-glass, and cover it with a sheet of shirt- 
 ing or calico. Support it also like a swing looking- 
 glass in a movable stand. This stand can be carried 
 to any open window or door, or even into the open air 
 when occasion requires. The swing-frame is then in- 
 cHned to receive the rays of the sun, and at the same 
 time the prints, which are placed side by side on the 
 cloth stretched across. An extra covering of net work 
 may be stretched over the prints to prevent them from 
 being carried away by the wind. By this contrivance 
 the prints soon dry and are kept clean. They are now 
 ready to be mounted. 
 
 MOUNTING OF PRINTS. 
 
 Make a paste of starch, in sufficient quantity for the 
 number of prints to be mounted, in the following man- 
 ner : Beat ordinary starch into powder and then into a 
 thin paste with a little cold water; finally, pour this 
 thin paste into boiling water, stirring the mixture well 
 all the while and adding to it until the composi- 
 tion is somewhat thick. Now remove the vessel from 
 the fire or lamp and set it aside to cool. When cool 
 it is ready for use. Place the print on its face and 
 brush over the back a sufficient quantity of paste un- 
 til the paper lies flat and is completely covered. The 
 print is now transferred to the mount and pressed 
 carefully and smoothly down in its right position. 
 The mounts, with the prints on, are put aside to dry. 
 
THE PHOTOGBAPHEr's GUIDE. 
 
 99 
 
 As soon as the prints are dry, the mounts are passed 
 once or twice between the rollers, which removes all 
 asperities, and gives them a complete finish as far as 
 photographic manipulation is concerned. 
 
CHAPTEK X. 
 
 THE NEGATIVE BY THE DRY PROCESS. 
 
 The aim of the photographer has long been directed 
 to discover some quick and reliable process by which 
 plates can be prepared in quantity beforehand, and 
 then can be carried out upon the field, exposed where 
 the landscape is attractive, again repacked and devel- 
 oped at home. Many processes have thus been dis- 
 covered which are, all of them, rehable in a certain 
 sense, but few of them are at the same time quick. 
 The latter consideration is, however, of little import- 
 ance, as long as the plate can be depended upon to 
 produce a picture under the circumstances prescribed. 
 The process, which seems to have given more satisfac- 
 tion than the rest, is that discovered by Major Kussell, 
 denominated the Tannin Process. With the alkaline 
 development, too, it is almost as rapid as the wet pro- 
 cess, but with this mode of development the process is 
 not quite as rehable as with the acid development. 
 Without any further prehminary we will describe the 
 process as we practice it ourselves. 
 
 the dry tannin process. 
 
 The plates are cleaned in the the usual way, and if 
 they are to be put away in a changing box, it will be 
 necessary to round off the corners, otherwise they 
 might be obstructed in their passage in and out of the 
 changing box and plateholder ; they are coated, too, 
 
THE PHOTOGBAPHEb's GUIDE. 
 
 101 
 
 •with a thin film of albumen in the nsual way. The 
 collodion, containing more bromide than iodide, is ap- 
 propriate for this sort of work; and the bath may be 
 fifty or sixty grains strong; still there is no absolute 
 necessity to change the bath; the one that you use for 
 the wet process will be suitable enough. Sensitize 
 the plate in the usual way; and, when the proper 
 cream-like color has been attained, take the plate out, 
 drain it and place it in a wash-basin of pure rain 
 water, collodion fihn downward, until another plate is 
 coated and put in the silver bath. As soon as this 
 second plate is in the silver solution, go back to the 
 first plate, wash the back of the plate, move the plate 
 backward and forward with an oscillatory motion, so 
 as to get rid of as much of the free nitrate of silver as 
 possible by this first washing. The plate is now trans- 
 ferred to a second wash-basin of pure rain water, 
 where it is again oscillated about and washed; it is 
 now taken out and allowed to drain for a moment and 
 then a dilute solution of bromide of potassium is 
 poured over it once or twice, the excess being returned 
 to the stock solution. 
 
 SOLUTION OF BROMIDE OF POTASSIUM. 
 
 Bromide of potassium - - 36 grains. 
 Water _ _ _ - - 3 ounces. 
 
 The object gained by flowing the plate with this so- 
 lution is to convert whatever free nitrate of silver may 
 still remain on the collodion film into bromide of silver; 
 any nitrate of silver, that might be left in the film, 
 would be detrimental to the good working afterward. 
 The plate is now washed again at the tap, or in 
 
102 
 
 THE PHOTOaEAPHER's GUIDE. 
 
 another wash-basin of rain water in order to remove 
 the bromide of potassium, and finally covered with 
 sufficient tannin solution to flow backward and forward 
 all over the collodion film. 
 
 TANNIN SOLUTION. 
 
 Tannin 150 grains. 
 
 Loaf sugar, or honey - - 150 " 
 Water - - - - - 10 ounces. 
 Alcohol, sufficient to dissolve the tannin. 
 
 Measure out the tannin, and add alcohol until it is 
 completely dissolved. Then mix this solution with 
 the sugar and water and filter through a moist filter. 
 The tannin solution is quickly prepared by the me- 
 thod here prescribed; it must be kept in a well-stop- 
 pered bottle. 
 
 We always use a fresh solution for each plate, and 
 pour the residue or excess into a vessel to receive it; 
 but the plate may first be coated with the tannin so- 
 lution which has already been once used, and then, after 
 draining, with a small quantity of the fresh solution. 
 After draining, the plate is reared on one corner on a 
 piece of blotting paper folded into several folds, and 
 left to dry in a dark cupboard or secluded shelf free 
 from dust. 
 
 All these different operations of washing and coating 
 the plate will not require more than two or three min- 
 utes ; and by the end of this time th e second plate will 
 be sufficiently sensitized in the silver bath to be removed 
 into the first wash-basin. These wash-basins are very 
 convenient for the washing purposes, because the plate 
 can rest on the four corners on the concave surface of 
 
THE PHOTOGRAPHEE's GUIDE. 
 
 103 
 
 the basin without any liability of the film being injured 
 by friction. This method, too, of preparing the tannin 
 plate entails no change or further outlay than that re- 
 quired in the wet process, as far as regards collodion 
 and silver bath. The process is easy and rehable. 
 
 EXPOSUEE or THE TANNIN PLATE. 
 
 Tannin plates, when dry, are put into the changing 
 box; there are two or three forms of changing boxes 
 in the market, but the one constructed by the Am. 
 Optical Co. in New York is, in our opinion, the best 
 and most commodious. With a httle ingenuity any 
 photographer may construct one for himself both 
 simple and effective and at a small cost. The inten- 
 tion of the changing box is to contain the plates so that 
 Hght cannot reach them, and, at the same time, to fur- 
 nish an easy method of transferring them to the plate- 
 holder and back again without allowing them for a 
 moment to be injured by any access of light. 
 
 All that the photographer requires on a photographic 
 tour, becomes reduced down to the three articles: 
 camera, tripod and changing box, all of which may 
 easily be carried in the hands, supposing that stereo- 
 scopic pictures have to be taken. Whenever, a charm- 
 ing landscape presents itself, the camera is mounted 
 upon the tripod, and the picture is focussed. A plate 
 is next transferred to the plateholder and exposed. 
 
 One pair of lenses which we use, requires an exposure 
 of three seconds in a good light to produce a very satis- 
 factory picture; with these lenses we expose a dry plate 
 under the same conditions of light for full one minute ; 
 that is, if we develop the plate with the acid devel- 
 
104 
 
 THE PHOTOGRAPHEE's GUIDE. 
 
 oper. The exposure, therefore, for a dry plate is about 
 twenty times as long as for a wet plate. Another pair 
 of lenses, the globe lenses, produce a good picture by 
 the wet process in five seconds; and by the dry pro- 
 cess we expose about a minute and a half. The ratio 
 in this case is nearly the same as in the preceding ex- 
 ample. With the alkaline developer much shorter ex- 
 posures would be amply sufficient; thus half the time 
 in either case would be quite sufficient. In some in- 
 stances you wiU find it necessary to make a short ex- 
 posure, in which case you make a note of the fact in 
 your note book and develop accordingly with the alka- 
 Hne developer. Most of our friends, who are success- 
 ful workers with the tannin process, decidedly prefer 
 the acid developer ; we prefer it ourselves. 
 
 ACID DEVELOPER FOE THE TANNIN PLATE. 
 
 Prepare the following stock solutions : 
 No. 1. — Acid, Pyrogallic. 
 
 PyrogaUic acid - - - 18 grains. 
 Acetic acid - - _ _ i ounce. 
 
 No. 2. — Nitrate of Silver Solution. 
 Nitrate of silver - - - 30 grains. 
 Kain water - - _ _ l ounce. 
 When required for use, make the following mixture : 
 For present use. 
 Of No. 1 - - - - 12 minims. 
 Rain water - - - _ 3 drachms. 
 Of No. 2 - - - - - 3 minims. 
 The collodion film is first made wet with clean water, 
 and the mixture is the then poured upon it so as to 
 
THE PHOTOGBAPHEr's GUIDE. 
 
 105 
 
 cover it. If the exposure has been right, the picture 
 ■will gradually begin to increase in intensity. Do not 
 hurry the development; let it proceed slowly. Should 
 the picture flash out very rapidly, add more acetic acid 
 to the developer, or prepare a new developer with only 
 one drop of silver, and ten or twelve drops of acetic 
 acid to twelve minims of No. 1, and three drachms of 
 water. When the action is slow, add more of the silver 
 solution. With patience you get all the intensity de- 
 sired. When the picture is thoroughly developed, it 
 has a rich, reddish tone-, and is quite intense in the 
 shades. Wash it well at the tap, and fix the picture in 
 a fresh solution of hyposulphite of soda containing a 
 Uttle alcohol, which will prevent the film from bHster- 
 iug; be careful to fix the picture thoroughly; then wash 
 with a bountiful supply of water, and examine it now 
 in strong daylight. If you do not Hke the red tone in 
 the negative, it is easily changed to a splendid purple- 
 black, by treating the film with the gold solution and 
 afterward with the acid bichloride of mercury, as re- 
 commended in a previous chapter, under the head 
 " Intensification." But you will find it more advan- 
 tageous to leave the negative red, because this color is, 
 comparatively speaking, non-actinic. 
 
 If the pyrogaUic were acidified with citric acid, that 
 is, if citric acid were substituted for acetic acid in all 
 the preceding manipulation of development, the finished 
 negative would have a bluish-black tone instead of the 
 reddish tone; and if nitric acid and gelatine were sub- 
 stituted, the tone would be of a grayish-black. It is 
 thus evident, that the acid used as restrainer, modifies 
 the tone of the picture. 
 
106 
 
 THE PHOTOGEAPHEb's GUIDE. 
 
 ALKALINE DEVELOPER. 
 
 Flow over the exposed plate dilute alcohol, contain- 
 ing equal portions of alcohol and water, and then pour 
 back the excess, and wash off the apparent greasiness 
 produced by the alcohol. Next pour over the plate the 
 following solution: 
 
 Carbonate of ammonia - - 1 grain. 
 Water - - - - - 4 drachms. 
 
 Pour the solution back again into the vial, and add to 
 it four minims of the following solution: 
 
 PyrogaUic acid - - - 30 grains. 
 
 Alcohol 4 drachms. 
 
 Water ----- 4 drachms. 
 
 Shake the mixture well up, and pour it again upon the 
 plate. The picture will now soon begin to appear, and 
 will proceed until all the detail is well out; but develop 
 as long as you like, the picture remains quite faint of 
 a reddish hue — it is a phantom picture. More of the 
 pyrogallic acid will hasten the development if the pic- 
 ture is quite slow in making its appearance. 
 
 The plate is now gently washed and flowed with 
 dilute acetic acid to remove the alkali; and all the in- 
 tensity you desire may be communicated to it by now 
 treating the film with the acid developer before given, 
 adding more of the silver solution to get great opacity. 
 When the acid developer becomes red or turbid, it is 
 better to prepare a fresh solution, otherwise you might 
 produce stains or asperities, which can not be removed 
 afterward. 
 
CHAPTEE XI. 
 
 TO PREPARE TRANSPARENT POSITIVES. 
 
 Transparent positives are prepared -upon glass, and 
 are positive pictures seen by transmitted light; they 
 are consequently quite distinct from ambrotypes, which 
 are also positives on glsss, but these, to be seen by re- 
 flected light, are, like daguerreotypes, inverted later- 
 aUy. 
 
 A transparent positive may be made either in the 
 camera or by contact printing. We have, consequently, 
 two cases: 
 
 POSITIVE printing ON GLASS BY MEANS OF THE CAMERA. 
 
 For this sort of printing, a copying camera is an 
 absolute necessity, a sine qua non, as the Professor of 
 Latin is always drumming into the ears of his lay 
 brethren. 
 
 Now, a copying is compound in form, but yet a very 
 simple apparatus. It consists, essentially, of two cam- 
 eras, one finished with a lens, and the other not; these 
 two cameras are screwed tightly together, endwise, so 
 that the bellows parts open in opposite directions; one 
 of these is intended to receive the negative, and the 
 other the sensitized glass, which is to receive the 
 actinic impression or the transparent positive. The 
 tablets which hold both the positive and the negative, 
 are furnished with spring clamps, either in the cor- 
 
108 
 
 THE PHOTOGEAPHEE's GUIDE. 
 
 ners or on the sides whicli are designated to hold the 
 respective glasses in their places. 
 
 As we have already remarked in a preceding chapter, 
 the negatives, which are in the best condition for such 
 like work as here comprehended, are very thin, trans- 
 parent and fuU of detail; we have described how such 
 negatives have to be prepared. Place such a negative 
 wrong side up in the shield, the collodion film looking 
 toward the lens; from such an arrangement it is e^d- 
 dent the copy in the conjugate focus of the camera wiU 
 be in its true and natural position; that is not inverted. 
 The sensitized is introduced, when ready, into the 
 opposite bellows, with the collodion film facing the 
 lens. 
 
 The focussing requires more than ordinary care; in 
 fact, you must be furnished with a magnifying lens, 
 which has already been adjusted in focus to the ground 
 glass surface, when it fits in contact with the back of 
 the ground glass plate. The camera may be placed in 
 such a direction as to receive the full hght of the sun 
 upon the negative, both during focussing and printing. 
 
 With a copying camera it is easy to find the equiva- 
 lent focus of your compound lens. We mean by this 
 equivalent value, the focal length of a double convex 
 lens that wiU produce a picture of an object of ex- 
 actly the same size as that produced by the combina- 
 tion, when the distance from the object to the lens is 
 in either case the same. When two such dissimilar 
 lenses thus produce the same result as to magnitude, 
 we say they are endowed with equivalent foci; but the 
 optical center of a double convex lens is its geometrical 
 center, and consequently is very easily found, the mo- 
 
THE PHOTOGEAPHEr's GUIDE. 
 
 109 
 
 ment we know the thiclmess; and the distance of this 
 center from the true burning point is denominated the 
 focal distance, this being the focal distance of parallel 
 rays, and is likewise easily measured by a practical ex- 
 periment. Furthermore, the distance between the ob- 
 ject (that is, the negative) and the ground glass, when 
 the pictures on the negative and the ground glass are 
 just of the same size, is four times the length of the 
 focal distance ; hence, if we focus the negative so that 
 the picture on the ground glass is accurately of the 
 same, and then measure the distance between the two 
 interior surfaces of the negative and of the ground glass, 
 and divide this distance afterward by four, we obtain 
 the equivalent focus of one compound lens. 
 
 Again, if the negative be brought nearer to the lens 
 than twice the focal length of the lens, the ground 
 glass will have to retire from the lens on the opposite 
 side, but not in the same ratio, but with an increasing 
 velocity; and the picture produced by such an arrange- 
 ment will gradually and quickly increase in size. But 
 if you once know the focal power of the lens and, at 
 the same time, you measure the distance from the nega- 
 tive to the center of the combination, which is an ap- 
 proximation to the optical center, you can, by calcula- 
 tion, tell the distance at which the ground glass has to 
 be placed in order to produce a sharp picture; that is, 
 a picture in focus. 
 
 The formula by which the calculation is to be made 
 is as follows: 
 
 v=f(n+l) 
 n 
 
 5 
 
110 
 
 THE PHOTOGBAPHEr's GUIDE. 
 
 in whicli v represents the required distance of the 
 ground glass, / represents the equivalent focus, n the 
 number of times the picture on the ground glass is to 
 be greater or less than the object or picture on the 
 negative. In plain arithmetic add one to the number 
 of times the picture on the ground glass is to be greater 
 or less than that on the negative; multiply this sum by 
 the equivalent focal length, and finally divide the pro- 
 duct by the number of times the picture on the ground 
 glass is greater or less than that on the negative. 
 
 The time of exposure in the copying camera will 
 vary with the power of the lens and the magnitude of 
 the picture. A picture of the same size as the original 
 negative, with a one-fourth compound lens, stopped 
 down to a circle of half an inch in diameter, in the di- 
 rect light of the sun, will require about ten or fifteen 
 seconds' exposure. 
 
 The collodion, the silver bath, and all other materials 
 used in developing and fixing are the same in this pro- 
 cess as in the ordinary negative process. The mode 
 of development is shghtly modified; either the devel- 
 opment must not be carried on as far as for a negative, 
 or the developer must be rendered more acid; the ob- 
 ject of either of these provisoes is to preserve the pic- 
 ture quite clear in the hghts. Carey Lea's ferro-gela- 
 tine developer is excellent for this purpose. 
 
 Use fresh fixing solution for each plate, and wash 
 very thoroughly. Transparent positives require ton- 
 ing; this is easily effected with the solution of terchlo- 
 ride of gold, and that of acid bichloride of mercury, as 
 previously recommended in the intensifying process as 
 
THE PHOTOGEAPHEb's GUIDE. 
 
 Ill 
 
 applied to negatives. After which the plate is again 
 carefully washed and varnished with a colorless and 
 transparent varnish prepared as follows : 
 
 VAKNISH FOE TEANSPAEENT POSITIVES. 
 
 Copal (tender) - - - _ i ounce. 
 
 Mastic (in tears) - - - 80 grains. 
 
 Venice turpentine - - - 50 minims. 
 
 Alcohol (95 per cent.) 10 drachms, (fluid 
 measure.) 
 
 Apply the varnish to the cold, but dry plate, and al- 
 low it to dry spontaneously. 
 
 TO PEEPAEE TEANSPAEENT POSITIVES BY CONTACT PEINTING. 
 
 This process requires the use of dry plates, and is 
 certainly one of the most interesting of processes in 
 photography. The tannin plate will suit our purpose 
 very well, but a plate prepared according to one of the 
 modified Fothergill processes will produce a positive 
 better than can be obtained by the tannin process; the 
 most beautiful transparent positive is prepared by 
 what is denominated the albumen process, which is 
 more difficult of manipulation than the preceding. If 
 the dry tannin plate be used, it will be necessary both 
 in the development and in the intensifying operation 
 to acidify the pyrogaUic acid with either citric or nitric 
 acid instead of acetic acid, which latter communicates 
 to the picture a reddish tone. The picture may be 
 toned afterward with terchloride of gold and the acid 
 bichloride of mercury in the usual way. 
 
 The negative is placed first in the ordinary printing- 
 frame, the film being upward; upon this is laid the 
 prepared dry plate, the collodion film being down- 
 ward; that is the two films are in contact. The frame 
 
112 
 
 THE PHOTOGBAPHEk's GUIDE. 
 
 is now closed, laid upon a small, flat board, to keep out 
 the light, and is then carried out of the dark-room, 
 where it is turned up and exposed for one or two 
 seconds to the diffused hght of day; or it may be ex- 
 posed for ten or more seconds to the light issuing from 
 a gas jet or from a piece of burning phosphorus or 
 magnesium. The plateholder is then turned over 
 again flat upon the small piece of board and carried 
 back into the dark-room, where it is developed hke 
 any other tannin plate. 
 
 TO PREPABE DRY PLATES BY GORDOn's PROCESS. 
 
 Any good bromo-iodized collodion is suitable in this 
 process; and the plate requires no previous substratum 
 of albumen or other material. Besides this, the plate 
 may be sensitized in the ordinary bath of nitrate of 
 silver, made shghtly acid with nitric acid. All these 
 are advantages in favor of this process. 
 
 After the plate has been properly excited or sensi- 
 tized in the silver solution, it is placed in a dish or 
 basin of distilled water, where it remains until a second 
 plate is so prepared as to take its place, when it is 
 transferred to a second basin of distiUed water. After 
 this it is washed gently at the tap and coated with the 
 preservative solution. 
 
 Have prepared the following stock solutions : 
 No. 1. — Albumen Stock Solution. 
 "White of egg (well beaten) - 1 ounce. 
 DistiUed water - - - 4 drachms. 
 Liq. ammonise _ _ - 5 minims. 
 
 No. 2. — Stock Solution of Nitrate of Silver. 
 Nitrate of silver - - - 30 grains. 
 Distilled water _ _ _ 1 ounce. 
 
THE PHOTOGEAPHEr's GUIDE. 
 
 113 
 
 From these solutions you prepare another every time a 
 plate is ready as follows: 
 
 Preservative Solution for Present Use. 
 Of the prepared albumen- - 4 drachms. 
 Ammonia _ _ - _ 5 minims. 
 Nitrate of silver solution - - 15 " 
 
 This solution is prepared as follows : Measure out in a 
 separate vessel the five minims of ammonia, then add 
 the nitrate of silver solution; this mixture is finally 
 added to the half ounce of albumen, and, after the 
 mixture has been well shaken, the mucilaginous-like 
 material is poured upon the plate so as to cover it, 
 moved backward and forward upon the plate, and then 
 the excess is poured back into the vial. A suffi- 
 cient quantity will be left with which to coat a second 
 plate; or, instead of this, half the quantity may be 
 prepared at a time for each stereoscopic plate. After 
 the plate has been thus treated, it is carefully and 
 evenly washed with one pint of water made to flow 
 from the narrow orifice of a long spout like that on an 
 oil can; it is finally swilled with distilled water and 
 placed away in a perfect hght tight box to dry spon- 
 taneously. 
 
 Exposure. 
 
 The plate is exposed about the same length of time 
 as that required for a tannin plate with the alkaline 
 developer, or about four or five times as long as is re- 
 quired for the wet process. 
 
 Development. 
 
 Flush the plate with distilled water and afterward 
 with a solution of plain pyrogaUic acid. Dissolve, for 
 
114 
 
 THE photographer's GUIDE. 
 
 instance, ninety-six grains of pyrogallic acid in an 
 ounce of alcohol, and afterward measure out five min- 
 ims (not drops) of the solution and mix it with four 
 drachms of water. 
 
 Let the solution flow backward and forward over 
 the plate for four or five minutes ; at the expira- 
 tion of this time, or perhaps even before, the image 
 will be complete in all its detail, although it will be 
 nothing more than a phantom image. In order to in- 
 tensify this phantom image, you now pour out again 
 five minims of the pyrogallic acid solution to half an 
 ounce of water, to which are added a couple of drops 
 of the following silver solution : 
 
 Acid Nitrate of Silver. 
 
 Nitrate of silver - - - - 30 grains. 
 Citric acid - - - - _ 40 " 
 Distilled water - - - - 1 ounce. 
 
 The image now soon begins to show more vigor, and 
 gradually becomes more intense. Proceed slowly and 
 patiently untH the picture is complete. If there are 
 any signs of under-exposure, use the smallest quantity 
 of silver; whereas, when the plate has been over-ex- 
 posed, a larger quantity of silver becomes quite neces- 
 sary. With plates prepared by Grordon's method, the 
 final tone of the negative depends, as is the case in the 
 tannin process, on the acid allied with the pyrogallic 
 acid, thus in the present instance, when citro-nitrate 
 of silver is used, the color of the negative has an olive 
 tinge, whilst with aceto-nitrate of silver it has a choco- 
 late reddish hue. It is not necessary to push the in- 
 tensity to the extent required in a wet plate, because 
 
THE PHOTOGRAPHEK's GUIDE. 
 
 115 
 
 of the non-actinic color of the negative produced by 
 either the tannin or this modified Fothergill process. 
 
 If the operator be desirous of getting a vigorous 
 final tone of a purple black color, he can do it by the 
 application of the toning and intensifying process with 
 terchloride of gold and acid bichloride of mercury. 
 
 There is no danger of the film sUpping off the plate 
 by this process; and if there is any tendency to blis- 
 ters, these can be obviated by adding to the fixing so- 
 lution a small quantity of alcohol. It is preferable to 
 use only a fresh solution of hyposulphite of soda in 
 fixing the dry plate negative. 
 
 TO PREPABE TRANSPARENT STEREOGRAPHS. 
 
 The chemical parts of this operation are in no way 
 changed from those just given for making any other 
 transparent positive; but, inasmuch as a stereoscopic 
 negative produces prints which are laterally inverted, 
 the right picture being on the left side of the paper, 
 whilst the left picture is on the right side, it becomes 
 necessary to cut the stereoscopic negative in two and 
 mutually to transpose the two halves and to mount 
 them on a separate glass. The proper plan is to cut 
 the two glass pictures down to the required size which 
 the paper prints are to have, and then to mount them 
 with a little transparent cement along the edges to the 
 glass support beneath. 
 
 As soon as the stereoscopic negative has thus been 
 transformed, we may place it in the printing-frame 
 and obtain from it by contact printing a copy in which 
 there will be no lateral inversion of the individual 
 prints, and in which the right picture is on the right 
 side and the left picture on the left side. 
 
116 
 
 THE PHOTOGEAPHEe's GUIDE. 
 
 There is anotlier method of preparing a stereoscopic 
 negative for contact printing; it is a very interesting 
 method, and consists in first obtaining a transparent 
 positive from the negative by means of two stereo- 
 scopic lenses placed side by side, and then from this 
 positive to obtain a negative by means of a single or- 
 thoscopic lens. 
 
 To effect the right conditions, the original negative 
 is placed wrong side up, and with the film facing the 
 lenses, in the copying camera; an impression is then 
 taken on a sensitized plate in the other bellows part of 
 the camera. The copy is a transparent positive, which, 
 when finished, is placed in front of the lenses, the film 
 looking toward the lenses ; these lenses are now taken 
 out, and a single orthoscopic or globe lens is substituted 
 in their place. A sensitized plate being placed on the 
 opposite side, a copy is taken which will be a negative 
 endowed with the requisite transformation for contact 
 printing. 
 
 But by camera printing a transparent stereoscopic 
 positive is obtained without the trouble of two opera- 
 tions. All that is required is to copy the original ne- 
 gative by means of two lenses as just described, the 
 resulting copy is a transparent stereoscopic positive 
 devoid of lateral inversion of every kind. 
 
 By any one of the three methods above described, 
 the picture is on the front of the glass, and on this ac- 
 count it requires two extra glasses when mounted, a 
 thin ground glass behind, and a similarly thin trans- 
 parent glass in front. By such a method there is, 
 therefore, a loss of material, and our aim naturally is 
 to obtain a picture free from all inversion when seen 
 on the back of the glass and not in front. 
 
THE photographer's GUIDE. 
 
 117 
 
 To effect this, that is, to prepare a transparent posi- 
 tive on the back of the glass there are several methods, 
 which the iagenious operator can easily find out him- 
 self ; we will describe only two. Take the original 
 negative, turn it wrong side up, and place it in the 
 shield of the copying camera, the film being outward; 
 copy this negative by means of two lenses, the result- 
 ing copy will be a transparent positive on the back 
 of the glass free from transposition, obtained by di- 
 rect camera printing. A second method consists in 
 first getting a negative so transposed as to allow the 
 requisite prints to be made correctly by contact print- 
 ing. This negative is obtained as follows: 
 
 Let the film of the original negative look outward 
 and take a copy as before by means of two lenses; 
 afterward copy the positive by means of a single lens, 
 the film looking inward toward the lens. 
 
 More extensive information on this subject may be 
 obtained by consulting the author's treatise denomin- 
 ated "Dry Plate Photography." 
 
CHAPTEE XII. 
 
 TO PREPARE OPAL OR PORCELAIN PICTURES, 
 
 This is an interesting branch of photograpliy, be- 
 cause the resulting pictures are exceedingly beautiful. 
 Opal or porcelain plates are translucent and of a milky 
 color; they may be obtained from the photographic 
 dealers of any size required. Those which are not 
 perfectly flat, are used for camera printing ; whilst 
 those which are quite flat originally, or ground flat, 
 are used chiefly for contact printing. Hence, there are 
 two methods by which opal pictures may be prepared : 
 by the wet, and by the dry process. 
 
 BY THE WET PROCESS. 
 
 Clean the plates Hke any other or the ordinary glass 
 plates, and then coat them with a dilute solution of al- 
 bumen, and put them away to dry. 
 
 The negative, which is suitable for such Hke opera- 
 tions, must be taken specially for the purpose with the 
 dilute collodion and by the method already described 
 in reference to copying and solar enlargements. Place 
 the negative inverted in the copying camera, the film 
 facing the lens. A sensitized opal plate is then placed 
 in the opposite bellows of the camera. It is custom- 
 ary to print opal pictures of the vignette shape ; this is 
 effected by a vertical frame parallel with the negative 
 and capable of sHding between the lens and the nega- 
 tive. This parallel frame is covered with an opaque 
 plate of thin metal or block cardboard, in the middle 
 
THE PHOTOGBAPHEr's GUIDE. 
 
 119 
 
 of which there is an elliptical opening designed to pro- 
 duce the vignette. Around the edge of the elliptical 
 opening a piece of tissue is gummed, and a smaller el- 
 liptical opening is cut through this tissue paper, con- 
 centric with the larger. The edge of this tissue paper 
 is then cut with a very sharp knife or a pair of scissors 
 into fine arrow hke projections all around. Any vari- 
 ety, shape and size of vignette can thus be prepared 
 and attached to the moving vertical sHde; and by mov- 
 ing the slide nearer to the negative or further from it, 
 a given vignette can be diminished or increased in size 
 ad libitum within certain Hmits. 
 
 The copying camera is placed so as to receive the 
 direct rays of the sun, or the bright, white Hght from a 
 cloud in the opposite part of the heavens to the sun; 
 in this position the sensitized plate is exposed for fif- 
 teen seconds or more according to the intensity of the 
 light and other circumstances connected with the 
 lenses and negative. The opal plate is then taken into 
 the dark-room where the picture is developed. 
 
 The ordinary iron developer is used for this purpose, 
 taking care, however, to make it slightly more acid 
 than for ordinary operations; thus, take half an ounce 
 of the developer, which will be sufficient for a common 
 card-picture, and add to it one drop of nitric acid. 
 Shake the developer and pour it uniformly and quickly 
 over the plate so as to cover it without any line of 
 stoppage. Develop until all detail is out, and then 
 stop immediately. Wash the plate carefully and fix 
 with a fresh solution of either cyanide of potassium, or 
 hyposulphite of soda. Finally, wash again very care- 
 fully and thoroughly. 
 
120 THE photographer's guide. 
 
 Tlie next part of the operation consists in cleaning 
 off the corners of the plate and removing all stains. 
 This is a delicate manipulation. Prepare tincture of 
 iodine by dissolving a drachm of iodine in one ounce 
 of alcohol. Place before you a wash-basin full of water, 
 and in a convenient place a beaker glass containing so- 
 lution of cyanide of potassium. Now pour a drop of 
 the tincture of iodine on one of the corners which is 
 stained; it will spread very rapidly and, at the same 
 time, convert the silver stain into soluble iodide of 
 silver; the moment there is any danger of the iodine 
 reaching any part of the picture itself, dip the plate 
 immediately into the water beneath and wash off all 
 the remaining tincture of iodine. Now pour some of 
 the solution of cyanide of potassium upon the same 
 corner where the stain originally existed; the part will 
 become thoroughly bleached; if not, repeat the opera- 
 tion with the tincture and cyanide until the stain is 
 removed. Every other stain is treated in the same 
 manner. If the picture itseK is stained, there is no al- 
 ternative but to make a new picture, because you can- 
 not remove such a stain without, at the same time, 
 bleaching some of the fine markings of the picture 
 itself. 
 
 We will suppose the plate has, however, been com- 
 pletely cleaned by the process prescribed; we now pro- 
 ceed a step further and tone our picture. Flow over' 
 the plate a dilute solution of terchloride of gold until, 
 the tone is uniformly changed all over the plate; then, 
 wash the plate. If it is intended to color the picture 
 by stippHng or otherwise, it will not be necessary to' 
 proceed any further; but where it is intended not to' 
 
THE PHOTOGEAPHER's GUIDE. 
 
 121 
 
 apply any color whatever, the tone of tlie picture may 
 be considerably improved by flowing over the plate the 
 dilute solution of bichloride of mercury, consisting of 
 fifteen minims of a saturated solution of bichloride of 
 mercury, fifteen minims of acetic acid and four drachms 
 of water. The intensity of the picture will increase very 
 rapidly to a certain extent, and then it retrogrades; you 
 must be careful, therefore, to stop its action in time; in 
 fact the picture seldom requires more than just to be 
 covered vnth the solution and then carefully washed. 
 After this operation the plate is thoroughly washed 
 and afterward dried. If the plate is to be mounted in 
 a case with a glass in front of it, it will not be neces- 
 sary to apply any varnish; but if a varnish is to be 
 used, it must be of a very fine nature and nearly 
 colorless. 
 
 An opal picture admits of being stippled so as to 
 imitate a perfect miniature gem of art, unsurpassed by 
 any other production of the same nature. 
 
 Owing to the innumerable stains which almost in- 
 variably are seen in stern contrast with the white por- 
 celain, operators in general prefer preparing these opal 
 pictures by some of the dry processes; and of these 
 dry processes the collodio-chloride process of Dr. G. 
 Wharton Simpson is by far the most expeditious. 
 
 COLLODIO-CHLORIDE PROCESS. 
 
 In this process the coUodion itself is made sensitive, 
 and consequently requires to be kept in a dark cup- 
 board. ■ It is better, also, to surround the bottle, in 
 which it is contained, with some non-actinic material 
 such as a metaUic case or with several folds of yellow 
 paper or cloth. 
 
122 
 
 THE PHOTOGEAPHEb's aUIDE. 
 
 Prepare the following stock solutions : 
 No. 1. 
 
 Nitrate of silver . - - 2 drachms. 
 Distilled water - - - 2 
 
 No. 2. 
 
 Chloride of calcium - - 64 grains. 
 Alcohol ----- 2 ounces. 
 
 No. 3. 
 
 Citric acid - - - - 64 grains. 
 Alcohol ----- 2 ounces. 
 
 When about to use this process, prepare the follow- 
 ing solution for present use: 
 
 Collodio-Chloride. 
 
 Plain collodion - - - - 2 ounces. 
 Nitrate of silver solution, No. 1, 30 min- 
 ims; Alcohol, 1 drachm, previously mixed. 
 Chloride of calcium solution, No. 2, 1 drachm. 
 Citric acid solution, No. 3. - 1 drachm. 
 
 Shake this mixture well up and then set it aside to 
 settle; in a quarter of an hour it will be ready for use. 
 By this arrangement small quantities of the coUodio- 
 chloride can be prepared quite easily; it is, therefore, 
 much better to prepare only just sufficient for the oc- 
 casion. 
 
 The albumenized plates are coated with this emul- 
 sive collodion as with any other collodion, and then 
 reared up to dry. When they are quite dry, they may 
 be albumenized in the usual way for about five min- 
 utes; this part of the operation is, however, not abso- 
 lutely necessary; it is optional. 
 
THE photographer's GUIDE. 
 
 123 
 
 Afte^ this operation tlie dry collodio-plate is ready 
 for exposure. Of course the reader must understand 
 that for this process we make use only of fiat plates, 
 either ground or unground, because in the printing 
 operation they have to lie in close apposition with the 
 negative, which must, also, haye been taken on flat 
 plate glass. 
 
 There are several printing-frames made specially for 
 this sort of printing; for an ordinary printing-frame 
 will not permit you to examine the printing as it ad- 
 vances. Shive was the first to get up an opal printing- 
 frame, which, with aU the accessories that have since 
 been added, is the most complete. Chapman's opal 
 printing-frame, as also Anthony's pneumatic porcelain 
 printing-frame, is exceedingly ingenious and appropri- 
 ate for the purpose in view. 
 
 The negative is placed in the printing-frame first, 
 and upon this comes the sensitised opal plate, the two 
 films, of course, being in contact; by the peculiarity of 
 construction of such printing-frames, the opal plate can 
 be raised from the negative, when occasion requires to 
 examine the progress of printing, and can again be re- 
 placed without disturbing the relative position of the 
 negative and the opal plate. The print is precisely 
 like an albumen print; it is produced directly by the 
 light of the sun, and consequently requires no develop- 
 ment after it leaves the frame. A slight over-exposure 
 is necessary. When the image is thoroughly brought 
 out and bronzing is just commencing, the opal plate is 
 taken fi'om the frame and washed by immersing it in 
 rain water and by oscillating it so as to remove any 
 free nitrate of silver. It is then transferred to a weak 
 
124 
 
 THE PHOTOGKAPHEr's GUIDE. 
 
 toning bath, where it remains until it is satisfactory. 
 From this bath it is removed to a vessel of clean water 
 where it is again washed, and afterward transferred to 
 the fixing solution of fresh hyposulphite containing a 
 Httle alcohol, which renders the film more porous and 
 less hable to blister. Finally, wash the plate and dry 
 it. It is now ready for the artist to be stippled or col- 
 ored as fancy, fashion or taste may suggest. 
 
 TO PRINT OPAL PICTURES BY DEVELOPMENT. 
 
 The plate is exposed either in the camera or in the 
 printing-frame as usual, but for a very short time, after 
 which the picture is brought out by development. The 
 developer used is that of gaUic acid and acetate of 
 lead, as recommended by M. Carey Lea, Esq. 
 
 Galhc acid ----- 6 grains. 
 Acetate of lead - - - - 3 " 
 Eaia water ----- 40 ounces. 
 
 The precipitate of gaUate of lead is dissolved by ad- 
 ding a few drops of glacial acetic acid. The opal plate 
 is immersed in this bath until the proper intensity is 
 acquired. It is then washed, toned and fixed as before. 
 
CHAPTER Xm. 
 
 TO PBEPAEE FEKROTYPES OR MELAINOTYPES AND AMBR0TYPE3. 
 
 These prints are positives to be seen by reflected 
 ligbt, and are in reality a sort of incipient negatives; 
 negatives not yet arrived at maturity. In these prints 
 the silver deposit, by reason of its whiteness projected 
 on a black background forms tbe lights, whilst the 
 shades are produced by the background seen through 
 the film, and, in the case of ambrotypes, through the 
 glass medium on which the picture is made. Fresh 
 and uncontaminated silver solutions and developers 
 are required in the production of pure and rich posi- 
 tives of this nature. 
 
 Japanned plates or paper may be had already pre- 
 pared at the photographic establishments for the pre- 
 paration of melainotypes, ferrotypes, etc. ; whilst for 
 ambrotypes thin, white or transparent plate glass is 
 used. 
 
 FERROTYPE OR MELAINOTYPE. 
 
 If the plate has not been used before, brush off the 
 dust with a camel's hair pencil, or polish it with a piece 
 of fine buckskin if necessary, then coat it with rather 
 a thin cadmium collodion and sensitize the plate in the 
 usual manner. 
 
 The plate, after draining, is then placed in the print- 
 ing-frame and a piece of glass plate is placed on the 
 back of it in order that the pressure of the lid or door 
 
126 THE PHOTOaEAPHEE's GUIDE. 
 
 of the printing-frame may be equal all over. Tlie ex- 
 posure may be a trifling less tban for a negative. 
 
 DEVELOPMENT OF A MELAINOTYPE. 
 
 None of the organico-iron developers are so well 
 adapted for the production of a rich melainotype, as 
 the ordinary and unsophisticated protosulphate of iron 
 developer. 
 
 Developer for Melainotypes. 
 
 Protosulphate of iron - - 2 drachms. 
 
 Acetic acid - - - _ 2 " 
 
 Alcohol 1 " 
 
 Eain water - - - - 8 ounces. 
 
 To produce a more metallic and silvery appearance, 
 the following formula has been much recommended: 
 
 Protosulphate of iron - - 2 drachms. 
 
 Acetic acid - - - - 2 " 
 Alcohol ----- 1 drachm. 
 
 Nitrate of potassa - - - 30 grains. 
 Nitrate of silver solution (30 grs. 
 
 to the ounce) - - - 30 minims. 
 
 Nitric acid - - - . Q " 
 
 Pour the developer quickly over the plate, holding 
 the edge of the vial close to the plate, in order that 
 the momentum produced by the fall of the fluid may 
 not produce a white speck on the plate beneath. As 
 soon as the image appears in full detail and before the 
 intensifying process sets in, the plate must be washed. 
 The knack is to find out exactly the right time when 
 to stop the development. It is as we have described 
 it, the moment between the two operations : that of 
 
THE PHOTOGEAPHEe's GUIDE. 
 
 127 
 
 developing the picture, and tliat of intensifying tlie 
 picture. The eye soon becomes inured to the change 
 of phenomena. It may happen that the detail does 
 not all appear before the transition from one subdi- 
 vision to the other takes place; in this case the expo- 
 sure has been too short; on the other hand, the devel- 
 opment is so rapid as not to permit one to catch the 
 exact moment when to stop, and the plate becomes 
 universally veiled by the silver reduction on the hghts 
 themselves; in this case the exposure was altogether 
 too long. You have, naturally, to study the capacity 
 of the lens with a given light, and its general working 
 powers ; you can then easily appromixate to the right 
 time of exposure on a given day. The requisites of a 
 good melainotype are perfect transparency of the glass 
 in the deepest shades, complete detail in every part 
 and a general brightness in the picture. If there is 
 any veil or fogging on the transparent parts, that is, 
 those parts which are to form the deep shadows, the 
 picture is a failure, and you will have to take it over 
 again. 
 
 Supposing you have hit upon the right exposure, 
 and have developed just far enough, wash the print 
 and then fix it with the ordinary solution of cyanide of 
 potassium, and finally wash and dry the plate. 
 
 All that now remains is to color it according to taste 
 and then varnish; or, which is still better, to varnish 
 it first and color it afterward with very fine colors in 
 powder. 
 
 It is customary to mount the melainotype in a case, 
 placing a mat first over the print and then a piece of 
 polished plate glass ; these are bound close together 
 
128 
 
 THE PHOTOGRAPHEe's GUIDE. 
 
 with the appropriate preserver, and finally fixed or in- 
 serted in the case. 
 
 AMBROTYPES. 
 
 An ambrotype is a positive on glass. The thinnest 
 white, that is, colorless plate glass, as far as is com- 
 patible with strength, is the best for this purpose. The 
 operations in every respect are the same in preparing 
 an ambrotype as those performed in the preparation 
 of a melainotype. When the print or picture is com- 
 plete, and has been caryfuUy washed, it is dried. It 
 is now ready for mounting. 
 
 It was customary, at an early date, to coat the back 
 of the plate with a thick black Japan, or varnish com- 
 posed as follows : 
 
 BLACK VARNISH. 
 
 Asphaltum - _ _ . 2 ounces. 
 Canada balsam - - - - 4 " 
 Oil of turpentine - - - 50 " 
 
 This varnish was laid on so as to form a uniform 
 coating and then dried. It is much easier, however, 
 to cut out a piece of black velvet of the size of the 
 plate and place it behind the picture. A mat is placed 
 over the picture, and a plate of glass is placed over the 
 mat; whilst another plate lies behind the velvet to 
 keep it uniformly in apposition with the back of the 
 plate. All these appendages are bound firmly to- 
 gether with the preserver, and then inserted in the ap- 
 propriate case. 
 
CHAPTER XIV. 
 
 THE SOLAB CAMERA AND SOLAR ENLARGEMENTS. 
 
 The . solar camera is in reality a copying camera, 
 with the simple addition of a lens or other attachment, 
 by means of which the sun light can be condensed 
 upon the negative, and thus made more powerful. 
 There are two distinct kinds of solar cameras; one is 
 fixed in its place, and the sun, by means of a reflector, 
 is made to shine along the axis in whatever part of 
 the heavens this orb may happen to be. The other is 
 suspended on two axes, a vertical and a horizontal, and 
 is thus capable of moving in any direction whatever, 
 and consequently of following the sun's motion, both 
 in altitude and azimuth. AU solar cameras of the 
 first class, are exact imitations of the weU-knovm solar 
 microscope. Woodward's solar camera was the first 
 in date, and, wonderful enough, it is protected with a 
 patent ! although the special function of the solar 
 microscope, previous to this patent grant, was to pro- 
 duce a picture, on a screen behind the lens, of another 
 picture or object placed in the conjugate focus in front. 
 Some improvements, in the way of directing the re- 
 flector horizontally and vertically, have since been 
 made in this camera, for instance, in Gale's improved 
 camera; and some have attached to them an arrange- 
 ment of clockwork, called a HeHostat, which regulates 
 the motion of the reflector according to the motion of 
 the sun, and thus keeps the sun's rays always parallel 
 
130 
 
 THE PHOTOGEAPHEK's GUIDE. 
 
 with the axis of the instrument. This attachment 
 makes this sort of solar camera, in one sense of the 
 word, perfect. Such a camera is fixed in a window 
 facing the South. This window is boarded up, so that 
 no hght can enter the room, excepting through the 
 lens. This room becomes, therefore, the dark chamber, 
 the camera obscura. The screen which receives the 
 image is movable upon the floor behind, so that it can 
 be brought nearer to the lens or well drawn from it, 
 according to the size of the picture required. This is 
 a convenient property of this sort of camera, an ad- 
 vantage which cameras of the second class do not 
 possess to the same extent. The general construction 
 of "Woodward's solar camera and of all its congeners, 
 is as follows : First comes a rectangular reflector, placed 
 outside the window, and capable of moving vertically 
 and horizontally, and of thus reflecting the sun's rays 
 perpendicularly upon a condensing lens, which is gen- 
 erally a plano-convex lens, the convex surface receiving 
 the rays. The negative comes next in order; it is in- 
 verted, and the film looks toward the portrait lens, and 
 is capable of motion to and from this lens by means of 
 a horizontal slide. The portrait lens or distributing 
 lens, comes next; it is fixed upon a frame which sHdes 
 horizontally. The axis of this instrument is a line 
 which passes through the center of the condensing 
 lens, of the picture and of the portrait lens, which 
 latter is placed at such a distance from the condensing 
 lens as to allow the cone of condensed light to come 
 to a focus in the optical center of the combination, or 
 at least in such a position that the conjugate cone of 
 light, and that of the picture itself, shall occupy as 
 
THE PHOTOGEAPHEe's GUIDE. 
 
 131 
 
 nearly as possible the same position, and be of the 
 same size on the screen. To produce this result satis- 
 factorily, requires a certain ratio to exist between the 
 power of the condensing lens and that of the dis- 
 tributing lens. This subject has not met with the study 
 which it deserves; and to the want of accurate know- 
 ledge, in this respect, may be attributed the general 
 failure of ordinary operators. If the cone of the con- 
 densed light, and if the cone of the picture do not 
 coincide, it is impossible to obtain a picture totally 
 free from what is denominated the ghost, which is a 
 circle of greater actinic force in the center than on the 
 periphery of the illuminated disc, unless the former 
 cone be thrown entirely out of the axis. Another 
 cause that tends to produce this ghost, is to be traced 
 to the spherical and chromatic aberration of the con- 
 densing lens. In some instruments this condenser is 
 partially corrected by the interposition of a concave, 
 or a concavo-convex lens, just before the hght reaches 
 the negative. This second, or correcting lens, converts 
 the converging rays of light into a parallel beam of 
 light, which simply illuminates the negative with a 
 highly condensed and nearly uniform light; and then, 
 of course, the two cases, of which we have just above 
 spoken, must of necessity coincide. By such an ar- 
 rangement, the best work may ba expected. Dr. Van 
 Monckhoven's instruments are arranged somewhat in 
 this manner; and the results are well known, and are 
 recommendations of the cameras. The screen, which 
 corresponds to the ground glass in the ordinary camera, 
 is placed vertically behind the distributing lens, and so 
 accurately that its center coincides with the axis of the 
 
132 
 
 THE PHOTOGBAPHEB's GUIDE. 
 
 instrument, and also that tlie distances of either edge, 
 laterally or vertically to the center of the lens, are in 
 pair respectively the same. 
 
 In the portable camera, of which Shive's, Roettger's 
 and Liebert's cameras are examples, there is no re- 
 flector. The instrument itself is tilted by the mechan- 
 ism peculiar to each instrument, so as to receive the 
 direct rays of the sun. This is an advantage over the 
 preceding instrument; because there is always a con- 
 siderable loss of light after reflection. Another dis- 
 advantage of the Woodward, etc, camera, arises espe- 
 cially in Winter, when the sun's altitude is small, and 
 the angle of incidence and of reflection is very large; 
 the light is thus made very weak by such reflection. 
 In the portable solar camera the screen, which is in- 
 tended to hold the sensitized sheet, has, but compara- 
 tively speaking, a short space to move in; and, conse- 
 quently, with this instrument it is very difficult to 
 obtain life-size figures, because an instrument that 
 would do such work, must, of necessity, be very un- 
 wieldy from its size. 
 
 To work with the solar camera, we proceed as fol- 
 lows: 
 
 Place the negative in its holder, wrong side up, and 
 a large sheet of white paper on the focussing screen. 
 Turn the reflector or the camera, so as to get the illu- 
 minated circle of Hght on the white paper; move the 
 negative imtn the picture on the paper is sharp all 
 over; by moving the negative nearer to the lens, after 
 it has once been focussed, the screen will have to be 
 shoved further off from the lens on the opposite side, 
 and the picture becomes thereby enlarged; whereas, if 
 
THE photographer's GUIDE. 133 
 
 the negative be moved back from the lens, the screen 
 will have to be brought nearer, which will make the 
 picture smaller. 
 
 As soon as the picture has been accurately focus- 
 sed, the light is shut off, and the sensitized sheet 
 is fastened to the screen by tacks or otherwise on the 
 place just occupied by the white focussing paper. All 
 being now ready, the hght is again turned on; and the 
 operator must see that the sun's rays are continually 
 kept so as to illuminate the same disc to the end of 
 the operation. By means of an aperture or door at 
 the end of the portable camera, and an obturator which 
 subdues the cone of light, you can from time to time 
 observe the progress of the printing. 
 
 There are two modes of solar printing, the one direct 
 and the other by continuation or development. The 
 former is the ordinary process of printing with albu- 
 men paper, which is sensitized in -the usual manner in 
 a large dish of nitrate of silver. Glass, photographic 
 ware or porcelain dishes for this purpose are the best; 
 but dishes made of thin wood, well dried and varnished 
 with two or three coats of varnish, will answer the pur- 
 pose quite as well and are far from being as expensive as 
 the former. Similar dishes, too, may be used for ton- 
 ing, fixing and washing the prints afterward. 
 
 The time of exposure, naturally, will be quite vari- 
 able, depending, as it does, on so many fortuitous cir- 
 cumstances; but, on an average, a good jDrint may be 
 obtained in about an hour's exposure to bright sun- 
 light. Print until the shades begin to be slightly 
 bronzed. 
 
 Tone and fix as usual. 
 6 
 
134 
 
 THE PHOTOGEAPHEk's GUIDE. 
 
 PKINTING BY DEVELOPMENT. 
 
 There are several methods of printing by develop- 
 ment; the following is the one pubhshed by Libois in 
 the Bulletin Beige : 
 
 Take thin Saxony paper and float it for a minute on 
 the following salting solution: 
 
 Chloride of ammonium - - 4 drachms. 
 Citric acid _ _ _ - 4 " 
 Rain water - - - - 25 ounces. 
 
 The citric acid is first dissolved in two and a half 
 ounces of water, and completely neutralized by bicai- 
 bonate of soda, five drachms of which are required to 
 neutralize three drachms of the acid. The solution of 
 citrate of soda, thus formed, is added to the solution 
 of the chloride of ammonium. The solution must have 
 a slightly acid reaction, which is attained by the addi- 
 tion of a few drops of citric acid ia solution. A small 
 quantity of boiled arrowroot is also mixed with this 
 bath, which is said to improve the final tones. 
 
 The paper is then hung up to dry, after which it is 
 sensitized by floating it on the following bath for half 
 a minute: 
 
 Nitrate of silver - - - - 1 ounce. 
 Water - - - - - 18 ounces. 
 
 This bath is acidified with a few drops of a solution 
 of citric acid. The first few drops produce a shght 
 precipitate of citrate of silver, which is immediately 
 dissolved by the succeeding drops. "When this is ef- 
 fected, the bath is sufficiently acid. 
 
 This paper, when dry, is ready to be tacked to the 
 
THE PHOTOGEAPHEb's GUIDE. 135 
 
 focussing-screen. You expose until the print assumes 
 a lilac hue, which will be a few minutes at most. The 
 image in this time will be just visible. The paper is 
 now taken out, and immersed in the following develop- 
 ing bath by Carey Lea : 
 
 Gallic acid- - - _ _ 6 grains. 
 Acetate of lead - - - - 8 " 
 Eain water - - - ■ _ 40 ounces. 
 To be prepared as follows : 
 
 Dissolve a drachm of gallic acid in four drachms of 
 alcohol, and a drachm of acetate of lead in twelve 
 ounces and a half of water. Take a drachm of the al- 
 cohol solution and twelve drachms and a half of the 
 solution of acetate; add these to one hundred ounces 
 of water, and then drop in just enough glacial acetic 
 acid to redissolve the slight precipitate of acetate of 
 lead that falls. 
 
 A number of prints may be immersed at the same 
 time in this bath. The development requires five or 
 six minutes in the dark-room, and is stopped the mo- 
 ment the prints appear perfect; over-printing is not 
 needed; for the fixing solution seems rather to im- 
 prove the detail than to destroy it. 
 
 Wash the prints and then immerse them in the fol- 
 lowing fixing solution : 
 
 •"^ater *----_ 20 ounces. 
 Hyposulphite of soda - _ g " 
 
 In this bath the prints remam about four minutes, 
 they are then washed thoroughly in a running stream 
 of water. The color of the prints, when they leave the 
 
136 
 
 THE PHOTOGEAPHEE's GUIDE, 
 
 water, is reddisli, but it assumes a beautiful deep 
 brown on drying. 
 
 Naturally the print may be toned like any other 
 silver print. In this case the print after development 
 is first carefully washed and then immersed in the or- 
 dinary gold toning solution, and afterward treated in 
 other respects like any other silver print. 
 
CHAPTER XV. 
 
 ViaNETTE PBINTINa. 
 
 PicTUEES formerly were sometimes surrounded with 
 a border or a garland of twisted vines, whence was de- 
 rived the name vignette or little vine. At present are 
 comprehended under this appellation all pictures of an 
 oval or circular form, situated in the center of the 
 mount, and shading gradually off by a stellar-Hke gra- 
 dation into blank space. Card-pictures are most gener- 
 ally so printed; in some instances the pictures are 
 printed as usual in the oval form, but the space which 
 surrounds them is shaded. It is our intention in this 
 chapter to describe this mode of printing. 
 
 In the first place the negative itself may be formed 
 into an appropriate condition for printing vignette 
 fashion; but in this case you have to be very careful in 
 focussing to place the sitter always and accurately in the 
 oval of the ground glass which he is to occupy in the 
 print; then, after exposure, the plateh older is taken into 
 the dark-room, and an oval piece of thick leather, with 
 bevelled edges, is placed on the back of the negative 
 in a position to correspond with the given oval of the 
 ground glass. India-rubber ovals might be made on 
 purpose, the under side being formed slightly hollow; 
 these, when pressed down into contact with the glass 
 beneath, will remain, by reason that then- elasticity 
 forms a vacuum beneath, firmly adherent to the glass. 
 A piece of tissue paper, somewhat larger than the 
 
138 
 
 THE photographer's GUIDE. 
 
 India-rubber oval, and cut with star-like indentations 
 on tbe edge all around, may be gummed upon the back 
 of the India-rubber oval. The plateholder is now taken 
 again into the light, the door or flap is opened, and the 
 plate is exposed for a few seconds to the direct action 
 of the hght. It is evident that the part beneath the 
 India-rubber or leather will be protected from the ac- 
 tion of light; the tissue paper, projecting beyond the 
 edges, with its stellar projections, softens the abrupt- 
 ness of separation between the picture and the sur- 
 rounding space. Naturally, the part protected from 
 the light can be made to assume any shape whatever 
 according to the contoxu: of the India-rubber discs. 
 The plateholder is now carried back to the dark-room 
 and the picture is developed. AH the parts external 
 to the oval obturator become quite opaque by the de- 
 velopment, more opaque than any other part because 
 of the direct exposure to the diffused light; and, conse- 
 quently, in the print the paper wiU be preserved quite 
 white, as it ought to be. "With a Httle practice this 
 mode of vignetting is very satisfactory; and the nega- 
 tives being complete in themselves, you have no further 
 trouble afterward in the printing operation. 
 
 Why is it not more generally practiced ? 
 
 Because, previous to the publication of this treatise, 
 it was not known generally, if at all. 
 
 The method in common practice is as follows : 
 
 A piece of tin plate, furnished with a rectangular 
 opening in the center larger than the oval vignette, is 
 placed first in the plateholder, then the negative and 
 after that the sensitized paper. Over the rectangular 
 opening there is another tin frame with an oval open- 
 
THE photographer's GUIDE. 
 
 139 
 
 ing which slides, or is so adjustable so as to bring this 
 oval opening right over the portrait. A rim of tin is 
 soldered all around the oval opening about half an 
 inch or more high, tapering off and forming the frus- 
 tum of an oval cone as it were. The inside is Hned 
 with black paper, and the aperture is covered over 
 with tissue paper. Along the edge all around there is 
 a concentric stellated ring of thicker paper, the star- 
 like projections of which point to the center of the 
 oval; another and similar ring, narrower than the 
 former, is glued upon this upon the outer edge; and 
 again a third still more narrower than the second. In 
 this way the light will be impeded into its transition 
 through the three layers of paper gradually more and 
 more to the edge of the walls of the frustum ; and the 
 conical shape of this attachment furthermore assists in 
 softening the gradation of shade into Hght. The gen- 
 eral principle being once known, the operator, if he is 
 worthy of his profession, can easUy modify the differ- 
 ent forms of vignetting to his taste and fancy. 
 
 Wooden vignettes are easily cut out of a piece of 
 soft wood, half an inch or more thick, taking care al- 
 ways to bevel the edge gradually toward the negative, 
 thus making the opening nearest the negative larger 
 than that on which the tissue paper is glued or 
 gummed. 
 
 When printing with a vignette of this construction 
 it is necessary to print vnth diffused Hght, if the plate- 
 holder is to remain quiescent when once laid down; 
 but if the light is direct solar hght, or a very bright re- 
 flected light from an illuminated cloud or surface, the 
 plateholder must be gradually turned around in order 
 
140 THE photogkapher's guide. 
 
 to equallize tlie iUumination and tlms soften the 
 shadows. 
 
 Another mode of vignetting consists in placing, first 
 in the plateholder, a so-called glass vignette. This 
 glass vignette is of the same size as the plate you are 
 using; that is, you may procure a quarter-plate vign- 
 ette, a half-plate, or a whole, etc., plate vignette. These 
 plates are made of glass stained of an orange-red or 
 yeUow color, and are non-actinic; but the central part 
 of the stain, which is superficial, is ground off on either 
 side of the plate of an oval shape, and the plain glass 
 beneath is then poHshed. These vignette glasses are 
 very convenient and highly satisfactory if the color 
 happens to be of the right nature. Two or three of 
 these glasses with various sized openings may be placed 
 one over the other, the smallest opening being outer- 
 most or most remote from the negative. 
 
 TO PRINT A DARK BORDER. 
 
 In order to print a dark border around a light oval 
 vignette, you take the print out from the printing- 
 frame when the picture is sufficiently advanced to 
 be called finished, and place an oval obturator of the 
 proper size over the portrait and a portion of the 
 white surrounding paper. The paper is then exposed 
 to diffused light until the tone is suitable. It is well 
 to turn the platform which holds the paper gradually 
 around during this exposure, otherwise the shade will 
 not be uniform. 
 
 Landscapes may be printed of the desired shape by 
 placing the ]Droper shaped mat in front of the negative. 
 
 When printing 'either with the copying camera, or 
 
THE PHOTOGRAPHEB's GUIDE. 
 
 141 
 
 the solar camera, it is immaterial in principle whetlier 
 the vignette is placed between the negative and the 
 lens, or between the print and the lens; it is sometimes 
 more mechanically advantageous the one way than it 
 is the other. 
 
 The toning, fixing and washing of a vignetted print 
 require no instruction; they naturally are the same 
 with this as any other print. 
 
CHAPTER XVI. 
 
 THE MAGIC PEINT. 
 
 The magic print is one that is developed by tlie 
 superimposition of a piece of moist paper upon a piece 
 of albumen paper which apparently contains no picture. 
 The operation loots like a feat of the enchanter. 
 
 The magic papers, the invisible prints, are prepared 
 as follows: 
 
 Print on albumen paper from the negative in the 
 usual way, but take the prints out whilst they are still 
 somewhat weak, but still complete in detail; that is, 
 you must not over print for this purpose. 
 
 The prints are then taken out, washed and fixed in 
 hyposulphite of soda, again thoroughly washed, and 
 then submitted to a bleaching process. 
 
 The bleaching, properly whitening solution, consists 
 of bichloride, of mercury: 
 
 Bichloride of mercury - - 1 drachm. 
 Water 4 ounces. 
 
 Immerse the moist prints in this solution and keep 
 them there until the pictures disappear. They are 
 now again thoroughly washed, dried and packed away 
 between folds of clean paper. 
 
 These magic papers are developed in the following 
 manner: 
 
 Dip pieces of blotting paper in a solution of hypo- 
 sulphite of soda, and whilst still moist place one over 
 
THE PHOTOGBAPHEb's GUIDE. 
 
 143 
 
 each albumen magic paper and put a weight over it to 
 keep it in close apposition. The print will gradually 
 reappear. When completely redeveloped the print is 
 thoroughly washed and dried. It wiU now keep for an 
 indefinite time. 
 
 The solution of bichloride of mercury does not de- 
 stroy the image, but simply combines with its silver 
 and forms a double salt which is white. This experi- 
 ment is quite analogous to that when oxahc acid in so- 
 lution is placed upon writing with common iron ink; 
 the vsrriting disappears, but it still remains in the paper, 
 it has simply become white writing, instead of black. 
 
 We have in the preceding chapters recommended 
 the use of bichloride of mercury as an intensifier, but 
 the reader must be careful not to carry the intensifica- 
 tion so far as ' finally to whiten the print. At the be- 
 ginning of the redevelopment the image grows more 
 and more black, then it gradually from this point be- 
 comes more and more white (not transparent). The 
 operator can easily see when to stop. 
 
CHAPTEE XVn. 
 
 WHAT TO DO WITH THE SILVEB AND GOLD KESIDUES. 
 
 The nitrate of silver in all the old residues of the 
 sensitizing baths both for paper and for plates, is re- 
 duced to the state of chloride of silver by the addition 
 of a solution. 
 
 The chloride is a white powder and soon settles to 
 the bottom of the vessel; the supernatant liquid is then 
 poured into another vessel, and again solution of salt 
 is added to it; if no further precipitate of chloride 
 of silver is produced, this hquid is thrown away. On 
 the contrary, if any chloride is stiU produced, add so- 
 lution of salt until the reduction is complete; decant 
 as before, and add the residue to the other. "Wash the 
 white precipitate in several changes of water, allowing 
 the silver salt to settle each time and then decanting 
 the clear portions. 
 
 This white chloride of silver may easily be reduced 
 to pure silver without the aid of fire. Keep the salt 
 under water in the dark-room until you have enough 
 to operate upon, and time to devote to the operation. 
 The following is the mode of reduction: 
 
 Take a bar of clean zinc as heavy as the quantity of 
 chloride to be reduced, and solder to one end of it a 
 silver wire; then cover the zinc completely with fine 
 gauze or mushn and dip it in clean water. Now im- 
 merse the zinc, so covered, in the moist chloride of 
 silver, and bend over the other end of the silver wire 
 
THE PHOTOGEAPHEr's GUIDE. 
 
 145 
 
 so as to come in contact with the chloride of silver at 
 a short distance from the remote end of the zinc. The 
 operation is best conducted in the dark-room. The 
 moment the connection is made with the silver wire 
 and the chloride, an electric current sets in and decom- 
 poses the chloride of silver into pure silver, which 
 manifests itself first at the loose end of the silver wire. 
 The chlorine which is set free hastens through the 
 musHn and combines with the zinc, forming chloride 
 of zinc, a very soluble salt which remains in solution. 
 The operation may continue until all the white chloride 
 has changed color and become silver gray. The bar 
 of zinc is now taken out and washed to remove any ad- 
 hering silver; it is much lighter than it was before the 
 operation. Dilute sulphuric acid is added to the silver 
 powder in order to dissolve any particles of zinc ; after 
 setthng a number of hou^s the supernatant liquid is 
 poured away, and the residue is well washed in several 
 changes of water. This residue is pure silver contain- 
 ing stiU, probably, some undecomposed chloride of 
 silver, which is no injury to it. The residue is finally 
 mixed with nitric acid containing an equal volume of 
 water; it is soon dissolved. If any chloride was in the 
 silver powder, it will be found now at the bottom of 
 the vessel undissolved, and can easily be separated by 
 decantation. This solution is then evaporated to dry- 
 ness on a water bath, and the residue is again dis- 
 solved in a small quantity of hot water and put aside 
 to crystallize. The mother liquor, or that part which 
 cannot be made to crystaUize, may be used for the sen- 
 sitizing bath for paper, after it has once more evapor- 
 ated to dryness. 
 
146 
 
 THE PHOTOGEAPHEe's GUIDE, 
 
 The undissolved portion of chloride of silver, if any 
 there w^ere, may be added to the next batch and treated 
 with it as before directed. 
 
 TO EEDUCE THE CHLOEIDE AND OXIDE OF SILVEE BY EIEE. 
 
 The method we have just described is a very reliable 
 one; but stUl, if you have the convenience, you may 
 reduce the residues to pure silver by fire; and the ad- 
 vantage here is that different residues, as for instance, 
 the chloride and the oxide, etc., may be mixed to- 
 gether and reduced at the same time. The paper 
 scraps, as we have already told you, are burnt in a 
 clean stove ; by this act the silver compound is reduced 
 to a mixture of silver and oxide of silver which will 
 form the ashes. These ashes and the chloride obtained 
 from the old baths, and the powder from the develop- 
 ing solutions, are all first thoroughly dried and then 
 intimately mixed with twice their weight of carbonate 
 of soda and chalk. The mixture is put into a crucible 
 which is heated afterward in a furnace to a very high 
 temperature, at which it is maintained until the silver 
 salts are thoroughly reduced. The mass is kept well 
 stirred up with an iron rod from time to time, and at 
 the end the temperature is raised to a white heat and 
 then the crucible is allowed to cool gTadually. The 
 silver will be found at the bottom of the vessel; or, 
 whilst the crucible is still at its highest temperature, it 
 is taken out of the fire, and its contents are emptied 
 upon a plate or dish of iron. The silver may be sep- 
 arated from the slag afterward by means of a hammer 
 and a pair of pincers. You will most likely find, also, 
 a number of silver pellets in the mass, which you can 
 
THE PHOTOGEAPHEe's GUIDE. 147 
 
 pick out witll a pair of pliers. The silver is next care- 
 fully washed in hot water, and finally dissolved in 
 nitric acid as before in order to make nitrate of silver. 
 
 TO EEDUCE THE GOLD EESIDUES. 
 
 Gold is obtained from old toning baths. The 
 method has already been described of precipitating 
 the gold by means of the protosulphate of iron, and 
 its separation from the silver by means of nitric acid. 
 The gold powder thus obtained may be melted in a 
 clean crucible into a lump of gold at a high temper- 
 ature. But this would be altogether a loss of labor 
 unless you want to get the value of the gold. As long 
 as you wish ■ merely to convert the gold powder into 
 chloride, the powder is just as good, even better, than 
 gold in the lump, because it is more easily dissolved in 
 the mixed acids in this form. 
 
CHAPTER XVIII. 
 
 LANDSCAPE PHOTOGEAPHY. 
 
 Negatives of landscapes are best taken in the Spring 
 or FaU of the year; in the Summer season, during the 
 extreme heat, the atmosphere is filled with vapor, 
 which obscures the view with haze; whilst in "Winter 
 nature has thrown off her robes of beauty and exhibits 
 herself in a state of dormancy. Still photographs can 
 be taken both in Summer and Winter; and Winter 
 scenery of icebergs and waterfalls is sometimes very- 
 grand. 
 
 There are two processes for the field, the Wet and 
 the Dry Process. Practical operators will at all times 
 prefer the process with which they are daily famiHar; 
 and we would advise them by aU means to keep to this 
 process; they wiU only lose their time and their pati- 
 ence if they meddle with dry plates, however much we 
 may personally approve of them ourselves. We have 
 seen already sufficient of the practice of dry plate pho- 
 tography in the hands of ordinary operators, to sym- 
 pathize with their failures and to condemn the prac- 
 tice. But whilst we thus warn practical photographers 
 against dabbhng in tannin, coUodio-albumen and coUo- 
 dio-bromide, we recommend these forbidden practices 
 to the amateur, who can bestow all his energies upon 
 them and is not fettered with the fixed habits of room- 
 work and the wet process. 
 
THE PHOTOGRAPHERS GUIDE. 
 
 149 
 
 The great trouble in landscape photography is the 
 weight of materials to be carried into the field, and the 
 construction of a portable dart tent. All the para- 
 phernalia reqmred in the field for the wet process may 
 now, however, be packed into a small compass and are 
 easily transported on a pair of Hght wheels. We have 
 tried aU sorts of tents, and possess four or five kinds. 
 Our tent for stereoscopic purposes is only two feet 
 long, one foot wide and one foot high ; and we can 
 operate in it as easily and reliably as in our large lab- 
 oratory, performing all the operations on the plate un- 
 til it is ready for varnishing. 
 
 Our tent for taking views, ten by twelve inches in 
 size, is at the same time . a camera. It folds together 
 into a small compass, and can be mounted in five min- 
 utes when once on the ground. 
 
 We have also a Carbutt box and tent for field-pho- 
 tography, which we should Hke exceedingly, if we were 
 not wedded to our own constructions which, to us, ap- 
 pear to work vnth more satisfaction. 
 
 With tents like these it becomes a real pleasure to 
 work in glens, among mountains and waterfalls; and 
 we believe that most of the photographic gems that we 
 receive from Europe, and those of Carbutt, Watkins 
 and others, the HeUographic pioneers of our own 
 country, have been produced by the wet process; and 
 it is well known that very few pictures, taken by the 
 dry process, were to be seen among the artistic pho- 
 tographic productions at the great exhibitions in 
 Europe. 
 
 All these facts seem to prove that practical photogra- 
 phers are one-sided in their views, and thus give pre- 
 
150 
 
 THE PHOTOGEAPHEE's GUIDE. 
 
 ference to the wet process; this will no doubt remain 
 so, until — until dry plates are not only as reliable as 
 wet plates, but as easily prepared by the ordinary 
 operator, and with the same collodion and silver 
 bath. 
 
"p7