Chapter III: The Inking-Up (1)

THE PRODUCTION OF THE DIFFERENTIAL SWELLING.—In the chapter on the bleaching we fully explained the processes which take place in the gelatine film under the action of the bleaching solution, and that the most important result of the bleaching process, aside from the disappearance of the silver image, is the formation of different degrees of swelling corresponding to the primary image, which in their totality form the tanned image produced in place of the photochemical image by the bleaching.

_For the success of the bromoil print, it is now of the utmost importance that the different capabilities of swelling, now latent in the gelatine film_, should be satisfactorily utilized. It is obviously possible to produce this swelling in very different degrees. The colder the water used for the swelling, the smaller the difference between the lights and shadows, while the warmer the water the more this difference is accentuated. If, for example, a print prepared for the bromoil process is placed in _cold water_ and allowed to swell for some minutes, the existing capacity for swelling will only be excited to a slight degree. The high lights of the invisible image only take up a little water, and when dry are differentiated from the shadows under oblique visual examination by a very delicate gloss or not at all. If this picture is now worked-up with greasy ink, a print is obtained with _a short scale of gradation, and its tone values are usually less satisfactory than those of the original bromide print_. If, on the other hand, the print is placed in _very warm water_, the swelling of the gelatine reaches a maximum. The high lights are very much swollen, even the half-tones are somewhat raised, and the shadows, which do not absorb water, appear sunken. The result of the swelling in such warm water in this case is the formation of a very pronounced relief, that is not only visible, but is almost perceptible to the touch. If such a picture is inked up, a bromoil print is obtained, _the contrasts of which are much stronger than those of the original bromide print_. Between these two extremes there is obviously a whole series of intermediate stages, the suitable employment of which permits of the most varied gradations.

As already mentioned, the capacity for swelling of the different makes of bromide papers is not the same in baths of the same temperature. This fact, however, argues neither for nor against the usefulness of the various bromide papers. It makes necessary, to be sure, a certain care in the use of a paper, the qualities of which are unknown. If one has to deal with such a paper, the prepared print should first be soaked in quite cold water; it should then be removed from the water, placed on a support, dried in the manner to be later described, and examined by oblique illumination as to whether the high lights show by a slight gloss that they have absorbed water. This will be the case if the image shows well swollen high lights; if they are not present, it will hardly be possible to find distinctly glossy places. In any case one may begin with the inking-up, prepared, as will be explained later, to increase the swelling if necessary during the inking-up by immersion in warm water. If on the other hand, the print, when taken from the cold water, distinctly shows places where differences of swelling are shown by a gloss or even a delicate relief in the film, the work may be proceeded with, without further trouble.

Under any circumstance one should be careful at first in the production of the differential swelling. _There should rather be no relief than too pronounced a one_; for differences of swelling that are too small can be easily and satisfactorily increased during the work; on the other hand it is scarcely possible again to reduce too strong a relief. While learning, or when using an unfamiliar brand of paper, it is therefore advisable to allow the sheet to swell first in cold water and to carefully begin the inking-up. Only if this is not satisfactory, should a warmer bath be used and the inking again tried. This method is, however, dealt with more fully in the section of Chapter III, entitled “Different Methods of Working” (page 85).

THE PROPERTIES OF THE RELIEF AND ITS INFLUENCE ON THE CHARACTER OF THE PICTURE.—In order that the following explanations may be understood, an important property of the prepared and dried gelatine film must be mentioned.

The film of the prepared print, in which the differences of swelling necessary for the formation of the bromoil print are latent, develops variations of relief when it is placed in water. Then the untanned high lights absorb water, as already described, while the hardened shadows do not absorb it. The result of this process is the formation of those swellings, which, when they have attained a certain degree, are characterized by the formation of a relief.

A definite degree of swelling corresponds to a definite temperature of water. This swelling disappears again if the film is dried. _The gelatine has, however, acquired the property of again attaining the same degree of swelling when immersed in water at any time after drying, even if the temperature of this water be a good deal lower._ A print, for example, on which a certain relief has been produced in water at 35° C. (95° F.) and which has given up this water again because of drying, again attains the same relief if immersed in ordinary tap water at 10° C. (50° F.). If, however, this print after drying is immersed in water at 40° C. (104° F.), that is in hotter water than that first used, a still higher relief is obtained, and again in a similar manner, after drying, it will attain this higher relief when immersed in water at any lower temperature.

_The degree of swelling that is once attained can, therefore, so far as the resistance of the gelatine film will permit, be increased, but it cannot be reduced_, if the print as a whole is not subjected to a tanning, as with formaldehyde, a process that is not easily controllable. This peculiarity of gelatine makes it necessary to go to work carefully in the formation of the relief, so as not to carry the latter too far. If the work is begun on a too low relief this can be easily increased to the necessary height, as will be shown later, absolutely without any regard to any inking up that may have been done. _On the other hand, if the formation of the relief has once been carried too far, as a rule the print can not be used_, although reduction of the excessive swelling by a tanning agent may be attempted.

The property of the gelatine film, just described, offers a further convenience for the bromoil worker; for he can bring the bleached and dried print to the necessary degree of relief in water of suitable temperature, and, if he does not wish to work it up at once, it can be dried and laid aside until needed. In working-up such prints he is then, as a rule, relieved of the necessity of obtaining warm water.

_The question how far the swelling of the film has to go or in other words what kind of a relief should exist, if any_, in order to obtain a harmoniously graduated bromoil print, is extremely difficult to answer. A few practical trials quickly give the ability to judge this correctly. If a well-modulated negative is used, one in which the differences of gradation between the high lights and the shadows are not too great, the swollen gelatine film after drying should show a very delicate but still noticeable relief; yet the high lights of the print should scarcely be raised above the shadows, and should not show too marked a gloss.

The visibility of the relief is essentially determined by the character of the print. The more contrasty the bromide print was, the more easily are the different degrees of swelling made apparent by the formation of a visible relief. A picture with sharp outlines and great contrasts, such as an architectural study, easily gives a distinct relief visible in all its details. Pictures with softer gradation, as, for instance, delicate portraits, behave differently. One can not expect a striking relief in such prints. If this should be forced by warming the water, the bromoil print may easily attain an undesirable harshness. With portraits, one should therefore be satisfied when the outline of the profile against the background, the contours of the eyes and the mouth, are raised to a barely visible extent from the gelatine base. At the same time very dense parts, like a white collar, a lady’s light dress, lace, etc., may show a very distinct relief, even when the sharper lines of the face scarcely stand out in relief. Yet even in such cases the features can be recognized by the different gloss of the high lights and shadows under oblique observation. Naturally some attention must be paid here to the particular views of the operator. If strong contrasts are desired, greater differences of swelling must be used; if, on the other hand, softly modulated effects are sought, distinct relief must be avoided. In any case it is advisable not to attain this at once, but to get it as needed during the working-up by the use of water gradually increasing in temperature.

_It must be laid down as an axiom that the efficiency of a relief should never be judged by the eye alone, but should always be carefully tested out by inking-up with the brush._ The degree of swelling is correctly estimated at the first attempt when, in inking-up, the picture appears quite clearly after a little hopping, and this may happen if the character of the image is right, even though no relief could be seen.

_The stronger the relief formed by warming the water, the more contrasty the bromoil print will be._ Nevertheless there is a certain limit which should not be overstepped. If the print is warmed in the water bath so much that an excessive relief, which can almost be felt with the finger, is formed, in which deeply cut lines alternate with highly glazed places in relief, then the high lights are so saturated with water that under no circumstances will they take ink; even the softest inks will not adhere to them. Thus we obtain harsh highlights without details, while the deeply sunken shadows literally fill up with ink and become sooty. If the formation of the relief has been driven so far, it is not advisable to treat the print with ink.

The forcing of the relief to the extreme possible limit is only justified when working with a flat negative, in order to obtain as rich a gradation as possible from a flat print. Also, this should not be done all at once before the commencement of the inking-up, but effected gradually during the work. Working in this way, extraordinarily successful results can be obtained and the contrast of the bromoil print can be made far more rich than that of the original bromide print. The limit lies only in the resisting power of the gelatine film and the flatter the bromide print was the sooner this is reached.

The upper limit of temperature permissible for the water can hardly be defined; it depends entirely on the hardness of the gelatine film. It may happen that it is necessary gradually to go almost to the boiling point. Films that are hardened right through will withstand even boiling water without forming a relief.

If, in warming the print, the melting point of the gelatine is approached, those parts which are but slightly tanned, such as the high lights, and especially any unexposed edges, begin to show a granular structure, and finally, when the heating is carried further, to melt.

_In the development of the relief great care should be taken that no part of the print remains dry_, and, if the film is placed face down, air bubbles should be avoided. If the print is placed face up in the dish, no part of it should project above the water, as it will then not absorb enough water; if the swelling has already taken place and a part of the film projects above the water (and this frequently happens, as the print, which at first lies on the bottom of the dish, after some time rises to the surface), the relief of the exposed parts goes down after some time, since the water evaporates from them into the air. Such insufficiently swollen parts, or those which have dried out, behave exactly as though they had been tanned more than the other parts of the surface. They have been able to absorb little or no water, or have lost the absorbed water by evaporation. They therefore take the ink, like the tanned shadows, far more readily than they would if they had retained the right amount of water, and far more ink adheres to them than should be the case and than adheres to the correctly swollen parts of the film. Thus patches of different form and size are formed at these places by the stronger adherence of the ink. Yet by renewed soaking of the print in the water these neglected places may be easily brought anew to the correct degree of swelling, and as far as concerns small spots caused by air bells, can be easily corrected. If larger patches of the film are insufficiently swollen, after the application of the ink they are usually much darker than the rest of the surface, and in such cases it is not always easy to obtain again the necessary evenness of the ink; it is then often necessary to ink up the whole print much more strongly than was originally planned, or to remove the whole film of ink.

Besides the warm water bath there is also another means at our command to produce the differences of swelling. This is the use of _ammonia_. A. & L. Lumière and Seyewetz, in a treatise published in 1913, on the resistance of gelatine to alkalis, found that cold solutions of ammonia did not attack gelatine but caused it to swell more.

If a bleached print is immersed in an aqueous one per cent solution of ammonia, the film attains in a very short time _the highest degree of swelling of which it is capable_, without the gelatine in the high lights being softened or damaged. The estimation of the height of the relief, which is so important for the successful carrying out of the inking, is scarcely possible with the ammonia bath, as it is extremely difficult to gauge its action. Therefore, it should only be used in those cases in which the highest swelling is absolutely necessary, as for instance, when using papers which have been strongly hardened in the manufacture, or with prints with very poor contrasts. A further application is with the transfer process, in which on the one hand it permits of the use of very soft inks and on the other hand enables one to keep the gelatine very resistant. Full details on the transfer of bromoil prints will be found in a later chapter. In very extreme cases, one may try to combine the action of the warm water and the ammonia bath, and use a warm ammonia bath. The ½ to 3 per cent solution of sodium carbonate recommended by E. Guttmann acts even more energetically than the ammonia solution.

As is obvious from the foregoing remarks, it will be as well to work usually with water baths and leave the ammonia bath for a last resource, the more so as in the swelling of prints in this bath certain troublesome phenomena may appear, which do not occur when using the water baths. Sometimes the bleached image reappears in the ammonia bath in a brown color; sometimes small white spots appear on the prints which will not take the ink and which, as can be determined by examining them by transmitted light, also exist in the substance of the paper; finally the gelatine film sometimes swells all over, so that the ink is not taken up anywhere. Prints which are failures in consequence of the use of the ammonia bath, should be dried and can be again treated in a warm water bath.

THE UTENSILS.—For the application of the ink the following are required:

_Brushes._—A best quality oil-printing brush with very elastic hairs cut on the slant, the so-called stag’s-foot brush, should be used. To apply the ink, a brush should be used with a working surface of from 1½ to 2½ cm (⅝ to 1¼ in.) diameter; by diameter is meant the length of the longer axis of the elliptical surface produced by the slanting cut of the brush. For working-up very small surfaces or for placing accents of color, a brush of about ½ cm (³⁄₁₆ in.) measurement should be used. In certain cases still smaller brushes may be useful. Such brushes are only used for working up details; they are only aids for special work. For the application of the ink generally, only the larger brushes should be used. It is far more difficult to apply the ink evenly with small brushes than with the larger ones, so that their use may cause needless discouragement.

The application of the ink is effected by placing the whole working surface of the brush charged with ink on the print, and then slowly lifting it up; this results in a deposition of ink corresponding to the working surface of the brush used. The smaller the brush the more often it must be applied, and therefore, the greater the probability of irregular inking, especially in those parts where the brush marks overlap. Also small brushes are handled less conveniently than larger ones and smear easily. The first thing to do in inking a bromoil is to obtain a good, even, thin film over the whole surface, to get a general impression of the whole effect. Only then is one in a position to judge how the tone values should be varied. The use of too small a brush unduly protracts this first operation and makes it difficult.

The brushes should be elastic but not too soft. Too soft brushes smear, that is to say, they deposit the ink in a thicker layer at their edges than in the middle and produce elliptical rings of ink, which must always be evened out by hopping.

In determining the size of the brush, the size of the bromoil print must be taken into account. Generally it is easier to work with brushes of from 1½ to 2½ cm (⅝ to 1¼ in.) in diameter. For large sizes up to 30 × 40 cm (12 × 16 in.) brushes of even 4 or 5 cm (1½ or 2 in.) may be used. Such brushes are not cheap, but are practically indestructible, if they are properly cleaned every time after use. The brushes are sold in tubular paper cases; these latter should be preserved and the brushes, after cleaning, put back into them, so that they are covered and the hairs do not get ruffled.

In order to preserve the brushes and keep them in good working order, they must be cleaned as soon as the work is finished, otherwise the ink left in them sets and makes the hairs brittle.

Brushes of long swine bristles with cut ends may also be used; with these especially, clean prints are quickly attained. They are superior to hair brushes of poor grade.

_The cleaning of the brushes_ is best effected as follows: Pour into a deep dish a _readily volatile_ fat solvent, such as benzol, trichlorethylene, carbon tetrachloride (carbona), etc.; but not turpentine, for if this be used the brushes cannot be used sometimes for days. Dip the brush into the liquid and press out the solvent on the edges of the dish, and stroke the brush vigorously on a piece of lintless linen, which should be used for this purpose only. The solvent can be used, ignoring the opacity which it soon assumes, as long as it will dissolve the ink. Only the hairs of the brush should be dipped in the solvent, but not the binding, as in some cases the cement with which they are fastened may be attacked.

_The Inks._—Theoretically, any ink prepared with a fatty medium is suitable for bromoil printing. In order to give satisfactory results, the inks must satisfy two conditions: they must have the correct consistency and their medium must be soluble in benzol. As regards the consistency of the ink it should be noted that the prepared film in its swollen condition, that is when the lights are saturated with water, absolutely repels greasy inks only when this swelling attains the highest possible degree; a case which one seldom needs and which will usually have to be avoided. If this swelling is not carried to the limit, the high lights, in spite of the water they hold, will take up the greasy ink, yet usually only when the ink is very soft. _The swollen high lights thus repel ink of thicker consistency, while they take the softer inks more easily in proportion as they become thinner._ That the tanned shadows also take hard ink is natural, for they do not contain, or contain only to a very small extent, the water which repels the ink. From these considerations it follows that in many cases satisfactory results cannot be obtained by using ink of only one consistency.

_The hard or heavy ink_ should have about the consistency of table butter, and it should be possible to spread it into an even smooth film on a glass plate with light pressure. _The soft or light ink_ should have about the thickness of honey and should spread under the knife without noticeable pressure.

_Collotype or copper-plate printing inks_ of various makes are frequently usable. As a rule, however, they must be tested as to their usefulness for our process; their consistency is frequently too hard, and sometimes they are not taken up by the film or cannot be distributed well, even when they are considerable diluted with linseed oil varnish, in spite of an apparently correct consistency.

The nature of the ink is not only influenced by the greasy substance used as a medium, but also by the material of the coloring matter itself. This is why many inks, in spite of their apparent softness, work tenaciously or “short,” while sometimes inks of hard consistency smear.

If occasionally the dilution of an ink of too hard consistency appears necessary, this is best effected with linseed oil varnish, which, however, should not contain any driers. If the work has been begun with a stiff ink of a certain shade and it is desired to retain this tone to the end, it is advisable not to use a thin ink for dilution, but to thin down the stiff ink with varnish.

_Inks of too hard nature_ are not practicable. Such were necessary in the oil-printing process. In the bromoil process, which is much less sensitive to the consistency of the ink, their use merely means a needless loss of time. An ink of correct consistency is easily taken up and produces quick drawing without smearing, while too hard inks are difficult to apply and soon refuse to take if they are not diluted.

It is extremely simple and advantageous to prepare the inks oneself, as outlined by E. Guttmann in Chapter VIII, p. 177. The process recommended by him is to place the powdered colors on a matt glass plate and rub up with varnish by means of a muller or pestle. This procedure is considerably facilitated, if, according to my suggestion, a few drops of a readily volatile oil-solvent be added. The ink is thus immediately liquefied and can be quickly and perfectly rubbed up. The solvent evaporates during the grinding, which is much easier than in the old way, and the ink again acquires the desired character without suffering in any way.

_As a palette for the ink_ the best thing is a piece of waxed or parchment paper, fastened on a white support, such as a card. Such a palette has the advantage that after use it can be discarded without cleaning. Moreover the color value of the ink can be fairly easily determined on it. If necessary old negatives, or other glass, may be used as a palette, and their use also makes cleaning unnecessary, which is an unpleasant and messy job.

A small quantity of ink should be taken and distributed as thinly and evenly as possible on the palette. A thick layer is not convenient, as then the brush takes up too much ink and too much is deposited at a time on the bromoil print. The film of ink should show as smooth and uniform a surface as possible; thicker ridges should be avoided, because the brush is thus more strongly inked in spots and therefore transfers the ink unevenly to the print. The distributed ink should be perfectly homogeneous and flexible. A thin layer of ink sets to a skin on its surface after a short time and then cannot be used.

This setting also takes place in the body of the ink and becomes evident by the formation of a delicate skin or hard crumbly particles on the surface of the ink. These must always be removed; such hardened inks can only with difficulty be distributed on the palette. Finally it should be mentioned that hard inks may be slightly softened by warming.

THE SUPPORT.—A stout glass plate or drawing board should be used as a support, and inclined at an angle of about 30 degrees by propping up at the top; _a damp and elastic pad_ must be placed on the glass or board. _This pad is not for the purpose of keeping the print damp during the working-up, as is usually stated_; on the one hand this is superfluous in view of the possibility of repeated soaking, which is to be described later, and on the other hand it would not produce the desired result. It is erroneous to suppose that the water which passes from the damp support to the paper side can equalize the loss of water which the film suffers by evaporation from its surface. The pad should, therefore, only be so damp that the bromoil print adheres firmly to it, when under the brush. The pad should absorb and hold moisture; but this should not be imparted to the brush when it touches the pad in working-up the edges, otherwise water will be carried on to the print and cause spots. _For this reason damp blotting paper or filter papers should be absolutely rejected for the pad._ If such papers are used for the damp pad, the brush, which in working the edges must inevitably touch them, will not only take up water but also the paper fibers and, transferring them to the print, cause trouble. Moreover, sheets of paper in a damp state are difficult to lay smooth and are scarcely usable.

The best material for the pad is the _copying sheets_ used for copying books, which consist of two layers of linen with an intermediate film of rubber. Such sheets have the advantage that when damp they always remain flat and smooth. A damp piece of linen, doubled and smoothed out, is also simple and certain. The pad must lie absolutely flat, because any ridges become most unpleasantly visible in inking-up, particularly with thin papers, as the brush always slips from the highest parts of the ridges and causes inequalities in the print.

REMOVAL OF THE WATER FROM THE SURFACE OF THE PRINT.—After the prepared print is removed from the water and laid on the pad, the water adherent to its surface must be removed. This is best effected in the following way: Take a large, absorbent, lintless cloth, spread it smoothly over the print, and press it gently with the flat of the hand. By repeating this, the water is easily removed without endangering the film; whether the drying is complete can be judged by _examining it obliquely. The freedom of the cloth, used for drying the print, from fluff and lint is of great importance._ If the cloth gives up fibers to the surface of the print, these cannot be seen at first. In inking-up, innumerable minute dark spots and lines appear on the film, as the deposited fibers take the ink very strongly and thus suddenly become visible. It is frequently erroneously assumed that such troublesome defects come from the brush. This is seldom the case; on close examination these fibers will be seen to be particles of the textile material. When possible, linen that has been frequently washed should be used for the drying.

When the water is to be removed from a print that has already been inked and again soaked, care should be taken that the cloth is freed from any folds by damping and subsequent drying, for such folds can, when pressed on the print, damage the film of ink. Although this is not of material importance, as such faults can be easily evened out by hopping, yet these small precautions avoid unnecessary trouble. Sidewise or wiping movements of the cloth should be carefully avoided, especially if the print has already been inked, because the ink is unnecessarily smeared by the wiping. After removal of the cloth one should make sure by examining the print obliquely that the water has been completely removed from the surface.

It is advisable to keep several cloths ready for drying off the film, for this will have to be done fairly frequently during the work. _Care should be taken to remove most carefully every trace of water; water which is picked up by the brush causes spots_, for the drops of water in the brush keep the ink away from the points of contact. In such cases it will be seen that white spots make their appearance in different parts of the print, continuously shifting their position during the work. By perfect drying off, these phenomena, which are in any case not necessarily important as regards the final result, can be avoided. In drying off a print already inked-up, the cloth will as a rule remove some ink from the surface; such cloths should not be used again until they have been washed, because they may transfer ink to a place where it is not wanted.

THE BRUSH WORK.—The prepared print, lying flat on the pad, and with its surface freed from adherent water, should now be inked up.

Before beginning the application of the ink a little stiff ink, at least as large as the working surface of the brush, should be placed in a corner of the palette. This should be spread out flat, thin and free from ridges; then the knife should be wiped and a little soft ink spread in another place.

The brush should now be pressed down on the _hard ink_ already distributed on the glass plate, and the ink dabbed very carefully from the brush on a clean place of the palette. _One should never go with the brush direct from the ink itself to the print, as this will form a spot which it is difficult to work out. It is of the greatest importance always to work with a brush that has been well dabbed out and in which the ink is evenly distributed._ If the brush has not been sufficiently dabbed out it leaves on the print a quantity of small, much darker and usually linear particles of ink, which cannot be distributed or are only removable with difficulty. Such spots must then as a rule be removed by the method described on page 72.

The whole brush technique is based on the following principle: if the brush charged with ink is placed on the print and allowed to remain there for a moment, and then _slowly_ lifted up, the ink remains on the image. If it is set down sharply and _quickly_ lifted (the so-called “hopping”), it removes ink. In the first inking-up of a print, the swelling of which has been correctly carried out, the application of the ink may be effected by a gentle dabbing. A very thin film of ink is thus produced and almost simultaneously correctly distributed.

The brush should always be held by the extreme end between two fingers, never by the middle or near the hairs. _The more lightly and more delicately the brush is managed the better it works._

It is best to begin the work at some characteristic place of the picture, which is well known to the worker; the ink should first be spread as delicately and evenly as possible on a small spot, avoiding, as far as possible, going over the same place twice with fresh ink. When the place selected has been covered with a light film of ink, the surface should be hopped over with light movements, when, with correct preparation of the print, the outlines will soon appear. _A bromoil print correctly prepared_, and with swelling suitable to the ink used, _is easily recognizable by the fact that the image appears delicately but distinctly under the very first strokes of the brush_. If this does not happen even after some time, either the degree of swelling of the print is too low or there is some fault in the preparation of the print, such as, for instance, unsuitable paper, a poor bromide print, errors in bleaching, etc. The longer the hopping continues, the more distinct the details should become. Then the application of the ink should be continued in places adjacent to those already worked up, until finally the whole surface of the print has been evenly gone over with ink and the image is visible in all its details, although still very thin and delicate. It is advisable to use a rough print from the negative as a guide.

_Beginners usually make the mistake of jumping from one spot to another without filling up the intervening parts._ This makes the work more difficult. Inking up should be carried out continuously by passing from those places already worked on to those not inked up. If it is noticed that the places which were first inked up appear too pale compared to their surroundings, since they have still too little ink, they should be inked up more strongly. Too dark spots should be evened out with the brush by removing the excess of ink and depositing it on the less inked parts. The amount of ink used on the print is very small; that which is first taken up by the brush lasts for a long time. It is not necessary to have frequent recourse to the ink spread on the palette by the knife, but is much better to take up, as long as possible, fresh ink from the spot on the palette on which the brush was dabbed.

_On the other hand, however, every application of the brush to the print should actually deposit some ink on the print._ If those parts touched by the brush do not increase in intensity, _it must be determined whether the dark places on the palette from which ink is supposed to be taken, are actually giving up ink_; for if the film of ink remaining on the palette is too thin, fresh ink must be deposited and distributed on it by the brush.

Care should be taken not to overload the brush with ink, for then the hairs stick together, distribute the ink badly on the print and, moreover, frequently leave large coherent particles of ink on the film, thus causing spots. As the brush is cut on the slant, it may happen that in dabbing out the brush on the palette and in the application of the ink to the print, the front and longer part of the brush is used more strongly. Then the ink collects at the back edge of the brush and causes spots when the brush is used more vigorously.

In many cases it is possible to complete the print with the hard ink alone. _If it is noticed that the hard ink does not take well on the print and is removed again in lifting the brush_, its consistency is too stiff for the work. One should not then continue to use it, but should _soften the ink_ in the following manner: First place the brush in the hard ink and dab it out well in another place on the palette. Now dip the ends of the brush hairs carefully and very lightly into the soft ink and dab out the very small quantity of the soft ink taken up by the brush on the same spot, on which the hard ink has been previously distributed. There is thus formed on the palette as well as in the brush a mixture of the two inks. Now try carefully whether the now softened ink adheres well to the print, by placing the brush lightly on a light place of the print. If it leaves behind a _light_ trace of ink without any trouble, the consistency is correct; but if this does not happen, the ink must be diluted again in the same way with the soft ink. If on the other hand the brush leaves behind a _strong_ trace of ink from a light touch, the ink is too soft and requires the addition of some hard ink. _It is not advisable to mix the soft and hard inks on the palette with the knife, as it is very difficult to strike the right consistency in this way._

This applies to all mixtures and dilutions of the ink which may be necessary in the course of the work, as in strengthening a colored ink with black, or in the preparation of any desired tint by admixture of different inks, and finally in softening inks with varnish. In all these cases mixing of the inks on the palette with the knife puts too much ink into use; also, as long as the ink is on the palette, one cannot estimate with the necessary exactitude either the tint or the consistency. The correct procedure is rather first to go with the brush to the first color and distribute this on a clean place, then set the same brush in the second color and make the mixture on the palette by dabbing. Then the mixture thus obtained should be tested as to its shade of consistency by gentle application to the print, and more of one or the other ink added in the same way with the brush. It should be noted that inks of a soft consistency go a very long way; the whole surface of the brush should never be dipped into such inks, but only the point of the brush. Softening of the inks with varnish should be effected in the same way.

When the first inking up is finished, the addition of ink of the same consistency is continued until the print is completed or will no longer take ink, which, as has already been pointed out, is known by the fact that the newly applied ink no longer adheres, but that the brush removes it from the print. Then one proceeds to a further dilution of the ink by taking more soft ink with the brush and adding it to that already mixed, and continues the work. The use of the unmixed soft ink is not even necessary in many cases. If, however, it proves to be necessary, it should be used, but with care, for a brush stroke which puts too much soft ink on any part of the print, especially in the shadows, causes a patch. _The beginner will work most easily and successfully if he always keeps the applications of ink as delicate as possible and obtains depth only by a repeated and even coating of ink, fully distributed every time._ If a place should still turn out to be too dark, one can try removing the excess of ink, if it be a hard one, with a clean brush. If a dark patch is formed by too vigorous application of a mixed or even a soft ink, another brush should be dipped into the hard ink, dabbed out, and the spot removed with this brush. Moreover, such places can as a rule be easily rectified after the second soaking of the print, which will be described presently. If the fault cannot be removed in this way, the ink must be partially or entirely removed, according to the instructions in Chapter III, page 73, and the work begun anew. This should be done without hesitation by the learner if the application of the ink does not succeed as he desires; the prepared print can be used for practice like a school slate by washing it off after each attempt with a solvent of the greasy medium.

For the application and the hopping off of the ink for large areas of the print one should _always use the whole working surface of the brush_. Smaller surfaces or outlines should be worked up with the front edge of the slantingly-cut brush; in laying on the ink one should never continue with the point, because this bends and gives unpleasantly sharply defined ink edges. _In order to cover a place with ink very thoroughly, one should hold the brush firmly, give it a slight twist and then raise it up straight and slowly._ If it is desired to coat a whole print evenly with ink, it should be applied in stripes over the whole print, the brush being pushed forward and not necessarily completely lifted up from the surface. The brush is pressed down firmly, the pressure relaxed a little, the brush moved forward half its width, then pressed again, and so on. In this way with a little experience there may be produced perfectly even ink stripes which bring out the outlines of the image and which are made close together until the whole print has been gone over, when one begins with the hopping. With papers with marked structure these stripes are best made in the direction of the structure and not at right angles. _Especial care should always be taken that the shadows of the print, which take the ink most easily, are not too strongly inked up, and one should try by light hopping to bring out all the desired details at the very first application of the ink._ When the shadows have once taken too much ink, it is not easy to clear them up by brush work alone. The inking up of large deep shadows must always, therefore, be very carefully done. Such parts of the picture are the most strongly tanned and therefore take the ink very readily and hold it very tenaciously. They should therefore never be touched with a brush freshly charged with ink, but one should work on the heavier shadows only when the brush has given up the greater part of its ink to the less sensitive parts of the image. Even then it always contains enough ink for the darker parts of the print. The first application of ink in the shadows, especially, ought never to be heavy and cannot be kept too delicate. When the desired details in the shadows appear to be well defined, they should then be strengthened. But even this should not be effected by a single thick coating of ink, but by successive additions of thin ink films and hopping after each.

Especial emphasis must be laid on the statement that _all details_, which it is desired to have in the finished print, _must be brought out by the first application of the ink_. If parts of the image are strongly inked up before the desired details have appeared, it is difficult to develop these later. On the other hand, detail, which has been brought out in the first inking, cannot be suppressed by any further skilful application of ink, but only strengthened.

These phenomena can on the other hand be successfully used to prevent the appearance of undesirable details in the picture. If for artistic reasons one desires to suppress detail and work flatly, the parts in question should be inked up from the start more strongly and evenly, and the hopping be either entirely omitted or stopped before the details which are to be omitted are brought out.

For beginners especially, it is useful in applying the ink, as well as in hopping, to lift the brush after every few strokes and examine the results obtained, so as to decide on further procedure.

One should accustom oneself to examine the print _from time to time at a certain distance_, while it is being worked on; for the correct impression as to whether the tonal values are correctly chosen, can be gained only at a greater distance; it is then seen more easily and clearly whether or not individual parts of the print carry too much or too little ink.

Particular parts of the print, which one wishes to have _more contrasty_, should be gone over after the hopping with _a wiping motion of the brush_; the ink is thus removed from the raised parts of the relief. If one goes too far in this, the inking can be done over again in the usual way.

If it is desired to free a brush from the soft ink, it should be dipped into hard ink specially spread on the palette for this purpose, and dabbed out well on a clean place, and this operation repeated two or three times, using each time another part of the palette. At the end of this manipulation the brush will practically no longer contain anything but hard ink.

When one has once learnt the initial steps of brush technique, in the course of time one fails to notice the difference between the laying on and the hopping off of the ink. _The hand in time acquires an instinctive handling of the brush, which takes care at once of both the application and the distribution of the ink_; if the proper relation between the consistency of the ink and the degree of swelling of the gelatine has been hit upon, a simplified handling of the brush comes of itself, because then the application of the ink is especially easy.

When, with papers of rough surface, the grain of the paper remains white in the shadows, in spite of hopping, such places should be treated by going over them with the inked brush with light pressure _with a rotary motion_.

_Practice teaches that there is always a definite consistency of ink which corresponds to a definite degree of swelling_ and with this the print may be executed from start to finish. If the operator has learnt by experience what ink consistency corresponds to the existing swelling of the film, he will prepare his ink of the suitable consistency, and is then in a position to carry out the work uninterruptedly without any new mixing of the ink.

It is a little difficult for the tyro to answer the question as to _when the application of the ink should be stopped_, that is to say, when the print may be looked upon as finished. There is frequently a temptation to consider the print finished when it is very delicate yet completely visible in all its details. The beginner often lacks the courage to apply more ink at this stage; he usually believes also that the print will take no more ink, because, as has been mentioned above, the part of the palette from which he has hitherto taken the ink, gives up no more. Such prints, which recall sketchy pencil drawings, deceive one during the work, but only satisfy later if this particular technique is suited to the character of the picture, which is certainly not always the case. One must therefore carefully consider during the work whether one should actually stop.

The second danger lies in the opposite direction, and is due to the fact that, led on by the constantly increasing vigor of the image, _one cannot rightly decide when to stop_. The danger here is that one is tempted by the vigor of some part of the picture to make the other parts also as strong in color, until by such continued action the print is immersed in the deepest gloom, which becomes still more gloomy after defatting the finished print. Such excess must be avoided as a rule. Experience and taste soon teach one to hit the happy mean.

The first, delicate and general application of ink, which may be considered as a guide print, is in many cases somewhat wearisome, especially when the picture has large areas of rich, deep shadows. With correct preliminary treatment of the print there are no real difficulties in the preparation of such a guide print. Yet the work, especially with large sizes, is really time-consuming and also offers, when considered from the artistic standpoint, but little interest, since the actual creative work of the operator only begins after the guide print is finished; only then is he in a position to actually give expression to his artistic feelings by suitable inking of the different parts.

Since, therefore, the work in the preparation of the guide print is actually quite mechanical, it is natural to make use of any means which enables one to facilitate and hasten this work.

For this there may be used, but only by the expert worker, a method based on the following considerations:

If an ink of suitable consistency is dissolved in a suitable solvent, such as benzol, carbon tetrachloride, trichlorethylene, etc., the pigment is very evenly disseminated in this solvent. If the latter again evaporates, the ink deposits in an even coating, unchanged in its nature.

It is therefore, possible, in the first application of the ink, to use such a solvent on the print and by its aid the wearisome mechanical work of the first inking may be rapidly and easily carried out.

In practice the method of procedure is as follows: there is first produced, on the print which is to be worked up, a relief which is vigorous enough to sufficiently develop all the detail in the shadows. An ink which is fairly stiff for this degree of swelling is chosen; the brush is first dipped in the solvent and then into the ink, which has been thinly spread on the palette. After a few dabbings on the palette the ink solution with which the brush is charged is spread on the print with a hopping motion and distributed with the same brush as evenly as possible. If the distribution becomes difficult in consequence of evaporation of the solvent, the brush should be again dipped in the solvent, and then the distribution can be easily completed. The film of ink thus obtained should be fairly thin, but must not be quite even.

After the complete evaporation of the solvent, the ink is worked up with a clean brush, with which the guide print can be finished without trouble and in the briefest time.

There are also other variations of this method of the application of dissolved inks. For instance, one may first apply some ink with the brush to the print and then distribute it with a second brush dipped in the solvent; one may also prepare a solution of the ink in a dish and paint it on the picture, or bathe the whole print in a solution of the ink. All these variants, especially the last two, have, however, certain disadvantages, so that the procedure first outlined is to be preferred.

After the guide print is prepared in this way, the further application of the ink is carried out in the normal manner.

The solvent is most conveniently chosen so that it is not too volatile, as for instance heavy benzol. But it ought not to contain any oil. When placed on the surface of the hand, it should evaporate fairly slowly, but without leaving any trace of grease.

Certain failures, which sometimes appear in this process, must be mentioned. If the film of ink is too thin, it can be repeated without further trouble in the same way, with rather more ink. If, on the other hand, too much ink is applied, a complete image is immediately formed without any possibility of the shadows being worked up. In this case the ink must be again removed by the solvent. If individual parts of the picture are too dark, from too much ink, it is sufficient to go over these parts with a brush dipped in the solvent, in order to clear them up.

If, after evaporation of the solvent, great irregularities in the distribution of the ink are seen, as for instance, spots and streaks which cannot be easily worked out, the print should again be placed in water; after drying off, the evening-up may be carried out without difficulty.

If in hopping with the second clean brush the image does not appear at once without trouble, either the relief was too low, or the ink too soft, or the solvent contained oil.