To this method belong principally: (a) Brush and pen designs; (b) the crayon method; (c) the transfer method; (d) the wood-cut method; (e) a sort of scraped style; and (f) spatter-work.
I
BRUSH AND PEN WORK
This is one of the best in lithography, and perhaps the best, because it touches daily needs most directly. It can be used not only for all kinds of writings, but also for illustration that does not demand the supreme perfection of copper plate. The ease of manipulation, the speed and the almost countless number of impressions recommend it especially. It may even be prophesied that in future, when true artists have become better acquainted with it, it will be used for high forms of art.
Much as this method has to recommend it, it has been used mainly for script and music, and it is difficult to gain adherents and followers for it. The reason is an apparently trivial thing, but it has made most artists averse to it. Since stone-printing exists I have found only two persons who could do anything with the steel pen at the first attempt. These were my brother Klemens, and a Herr Porner, who works now in the establishment of Herr MÜller in Karlsruhe. All others have had to struggle more or less with this slight trouble, and yet it does not demand more than a few days of patience and study.
For pen work one must not be too particular in selecting stones, as the less perfect ones are more available for this than for any other method. However, the general rule holds good here, too, that the purest and hardest stones are best.
If they have been used previously, so that the fatty inks have penetrated pretty well, they still need not be ground too deeply, but it will suffice to grind them merely till all depressions and elevations of the previous design have vanished. They may be ground with sand or pumice, so long as they are made smooth so that no roughness can be perceived. The smoother and finer the surface is, the easier will it be to work on it with the pen.
To design well on stone with chemical ink, the stone must be prepared after grinding so that the ink shall not flow and spread. Dissolve one part of tallow in three parts of oil of turpentine and coat the dry stone very quickly. With a clean rag or tissue paper wipe it at once so thoroughly that the coating vanishes again almost entirely, leaving only a thin film that can be easily devoured and removed when the etching fluid is applied later. It is well to do this some hours before beginning work on the stone, partly to give the turpentine odor time to evaporate and partly because it is easier to work after a little while than immediately after coating the stone. The stone can be prepared far in advance, even so long as some months before using. In that case it is necessary merely to clean the dust away with a cloth or fine brush. This should be done anyway at intervals during the work, or it will clog the pen.
I prefer another way of preparing the stone for designing, because it is one that insures the stone against containing any hidden preparation, which can easily occur in grinding owing to carelessness or uncleanliness on the part of the workman, especially if many old plates are being reground, when the gum which most of them contain from previous use will mix with water during grinding and thus form a partial preparation of the stone.
I coat the plate with strong soap-water containing many soapy particles, and dry it off as well as possible. Now, there will be too much alkali on the plate, which will not be good for fine work. I pour a few drops of clean water on the stone, make it quite wet with this and dry it again thoroughly. The fat of the soap will then have precipitated itself on the stone and at the same time has lost all alkali. The soap-water must not be too thin, as in that case it will precipitate too much fat on the plate at once and the etching fluid will not be able later to destroy it properly. This would mean the total destruction of the design. To make quite sure, I advise beginners, after applying soap-water and drying it, to coat the stone with the tallow and turpentine solution, clean it quickly, and thus be absolutely assured that the plate is thoroughly prepared for the design.
It must not be imagined that this preparation for work is not very important. I am convinced that less depends on the quality of the ink than on a surface freed from all acid and mucous substances and provided with a sufficient amount of fat.
On the stone thus prepared the rough design may be done with lead crayon or red chalk or by tracings or transfers. Any surplus of lead or red chalk would make trouble during the succeeding completion of the design with chemical ink, and must be removed carefully. If the design has been laid on by transfer, the resultant fattiness must be lightly rubbed away with a fine sand, but not so as to injure the design.
This method, of first drafting the design on paper with soft chemical transfer ink and then transferring to stone, offers such advantages that it pays to practice it. Care must be taken to remove all surplus of color, as otherwise all lines that should not appear will resist the etching fluid and gradually show again. Those who fear destruction of the design by the use of sand can effect the same purpose by printing off on clean waste paper a few times, or the design may be printed off on paper before being transferred, thus cleansing it of surplus fat.
When the design has been laid on the stone clean and strongly with chemical ink, the plate can be etched and prepared, but not till the whole design is perfectly dry, because otherwise it cannot resist the action of the fluid.
The parts finished first usually are dry long before the entire work is finished. A trained eye can recognize the proper degree of dryness from the sheen, which varies with different kinds of ink, but on the whole is always duller when the design is dry than while it still is wet. It is highly necessary that the design be thoroughly dry. It is possible to keep a designed plate for years without etching it, so long as it is protected against injury.
Etching is done in two ways, painting the fluid on and pouring it on.
The former method is less circumstantial, but is used only in coarser work, because there is always danger of damaging delicate parts of the design. It has the advantage, however, that any dirt caused by corrections will be removed. A mixture of three or four parts of water with one part of aquafortis is painted over the stone with a soft brush of fox- or badger-hair. The brush must be dipped continually because the fluid loses its power.
For the second method the stone is placed in a large wooden trough or box, provided with cross-pieces to keep the stone from the bottom. The acid, thinned down with thirty or forty parts of water, is poured over it. It is rather immaterial how much one may dilute the acid. Very weak solutions simply mean that the pouring must be repeated oftener. The fluid acts on stones according to their degree of hardness. Regard must be had, too, to the delicacy of the design, very fine lines being unable to resist etching that does not affect coarse lines.
Only slight experience is needed to recognize the effect of the acid. By looking at the stone sidewise and against the light, the growing elevation of the design can be perceived easily. When the fatty coating caused by the soap or turpentine wash has been etched away completely, and the water adheres equally everywhere, the stone generally is sufficiently etched to be ready for preparation and printing.
For the sake of easier printing, and also so that future grinding and any desired improvement may be done on the stone, there should be a little more etching, if the design is not too delicate. But if the design is very fine, the etching absolutely must not be more than strictly necessary, because the fine lines might easily be eaten away. Coarser designs can bear strong etching which often may reach the depth of a thick paper. But an inordinate amount of etching is not to be recommended, even if the design can bear it, because the edges of a deeply etched line are rough and take the color so strongly that it works into the cavities and is very hard to get out.
When the stone has been properly etched, clean water is poured over it to wash away the free acid. Then the work of preparing the plate with a solution of gum arabic in four or five parts of water can begin at once, or the stone may be set aside to dry, thus giving the finer parts of the design, that may have been most affected by the acid, time to adhere again to the stone and soak in, which can occur only in the dry state. This is entirely unnecessary with most pen drawings, but with brush and especially with crayon work it is of great value.
When the stone has been prepared with gum, it is set aside to rest for a few minutes. Then pour a few drops of water and exactly the same quantity of oil of turpentine on it, spread it in all directions uniformly and wipe the entire design off clean with a woolen rag. Hard ink, especially if it has been on the stone for some time, is more difficult to remove and a little more turpentine is required. The stone should now be inked-in at once, because the turpentine, and with it all the fattiness, is liable to extensive evaporation, and then the stone will not take color well.
Inking-in of the pen designs is done as follows: A clean linen or woolen rag is soaked in clean water and wrung out till it is damp rather than wet. This is passed over the whole stone so that it becomes a little wet everywhere. Immediately after this dampening, the well-inked printing-roller is passed to and fro over the plate several times. The roller must be lifted frequently during this work so that the points of contact change. To lay the color on well and quickly, the roller should be held rather firmly in the beginning, well pressed down and used with a certain rubbing motion that will tend to lay color on the design sideways, so to speak. Then the roller must be allowed to roll to and fro a few times without much pressure, to spread the color and take away any surplus. Do not roll too long, till the stone dries, because then it will take dirt immediately. Should this occur, it must be wiped instantly with the damp cloth till it is clean again. If dirt is left too long, it will be extremely hard to remove.
Beginners usually wet their plates excessively to counteract this trouble of drying during the inking-in. This results in wiping away fine strokes, and the roller gets so wet that no good impression can be made till it has been dried sufficiently again. For this reason beginners should not use bath-sponge, because, though it is excellent, it leaves too much water on the stone unless one knows exactly how to use it.
Some printers put a little gum, others a little aquafortis into the water to wet the stone. Others use stale beer, or even urine. I consider all this unnecessary, if the stone has been prepared correctly and the color is good.
I have described the ink-rollers. I repeat that they must be uniform, soft, and elastic.
As to the inking-in color, I am not able yet to lay down a strict rule. All that I can say, as a result of my experiments and experiences, is:— (1) The firmer the varnish in a color is, the cleaner is the work of inking-in.
(2) The same is true the more lampblack it contains.
But in both cases the finer parts of the work are easily rubbed away, and too much lampblack makes the lines squash the impression.
(3) The toughness or fluidity of the color must bear correct proportion to the power of the press. The harder the varnish, the more power is required in the press.
(4) Tough varnish is not so liable to squash under pressure, but if it has once been pressed into the spaces between the lines of the design it is not readily removed by the mere action of the inking-roller, and this causes more and more smutting and, finally, total ruin to the stone. Generally when a tough color has adhered too much, there is no other remedy than to clean the stone well with gum and oil of turpentine; and this, if done too often, damages the preparation and makes the impressions continuously poorer.
(5) Soft color spreads more readily under pressure, but is removable after each impression by merely dampening the plate.
(6) In using soft color, the paper may be kept damper than with hard colors.
(7) Soft as well as hard printing-color, if not mixed with the proper amount of varnish, has the property of producing poor, sooty impressions because of a defect called shading. Shading is caused as follows: If a drop of oil falls into a basin of clean water, a part of the oil will spread immediately. Now, a stone is wetted before inking-in. After the inking a considerable portion of dampness remains. If the ink is very fluid, it will happen often that a part of it will spread away from the design to the surrounding moisture, producing something that looks like a shadow around every part of the design. This does not occur instantly, as in the case of the pure oil, but gradually, so that it is not as noticeable when the swifter lever press is used as with the slower cylinder press or if the workmen are slow. If a stone can be dampened so exactly that with the last touch of the ink-roller the last vestige of dampness is removed, this is not likely to happen. But it is difficult to arrive at such accuracy. It is better to add enough lampblack gradually to the varnish to make it lose its elasticity, when the shading effect will cease.
(8) While shading is obviated largely through enough intermixture of lampblack or other coloring substances to take away the fluidity of the printing-color, this intermixture will cause other troubles. The finer places will not take the harder color so well, whereas at other places too much will be taken. Also an impression made with much lampblack will off-set more than one made with color in which varnish predominates. Neither will the impressions be so black. Experience teaches that a printing-color that has less lampblack will be blacker, because the sheen of the varnish will make the color strong and lacquer-like. I have tried to invent a kind of varnish that would not be so liable to shading and thus would permit a greater fluidity with safety, but lack of time has prevented me from exhausting the possibilities. I am sure, however, that it can be done, for I have found that the common linseed oil varnish can be made to lose its property of shading by admixture of fatty and resinous bodies. For instance, the addition of a slight amount of Venetian turpentine permits a greater fluidity. Very good is the following composition: Six parts linseed oil, two parts tallow, one part wax, melted together and thickened by boiling down and burning like the ordinary linseed oil varnish.
(9) The inner composition of the stone and the temperature have a considerable effect on the print and also react on the color. A stone, especially a porous one, has much less internal moisture on very warm, dry days. Then the dampening done before each impression often evaporates instantly and unequally, so that it is difficult to ink-in uniformly with a soft color or one lacking varnish, unless one wets the stone unduly, which, again, injures the impressions. In that case one must use a color that is firmer than should be used according to ordinary rule. It is also well, before printing from the stone, to lay it in clean water for a few hours, or overnight, so that it may soak in enough moisture to make it easier to dampen.
(10) If the drying of the printing-color is to be hastened, as is necessary with some work, a little finely powdered mennig may be mixed in. Finely powdered litharge of silver dries still better, but only a small amount of printing-color must be mixed with it, because it toughens within an hour. It will not keep for another day, because the mennig will dissolve after a while.
In printing from the pen design, the following must be observed:—
Even if the stone has been inked-in uniformly and well with a good color, the impression can be spoiled in various ways: if the paper has not been dampened as required by the nature of the color and the power of the press; if the pressure is not in proportion to the consistency of the color; if the scraper is not even, and if the leather is not properly stretched.
Therefore care must be taken in printing pen designs:—
(1) The paper must not touch the inked design till the scraper forces it down. It is not advisable to lay the paper directly on the stone. It should be in the printing-frame, which, as already described, should be so arranged that it will keep the paper at least one fourth inch away from the stone.
(2) The proper dampening of the paper is not a matter of the greatest importance in pen designs, so long as it is not too wet, in which case it causes squashed impressions, does not take color uniformly, and, if the printing-color is tough, will stick to the stone. In general, the rule holds good that the degree of dampening must be in proportion to the firmness of the varnish, and that a softer varnish permits increased dampening. Dampening is done chiefly to soften the paper, and the qualities of the paper dictate the amount necessary to a large extent.
(3) The tension of the press must be more powerful with hard printing-color and carefully graduated with soft color. Besides this, it depends—
(4) On the structure of the scraper. If it is not absolutely uniform and well fitted to the stone, more power is needed. Thus the defect often is corrected; but this may make the color squash and spread in other spots, therefore it always is better to correct any defects in the scraper. The sharper the scraper is, the clearer are the impressions, because then the whole force of the pressure concentrates on the smallest area. But usually the scraper soon becomes dull, and then the press must have more power.
(5) Insufficient tension of the leather also may produce poor impressions, especially if the color is soft and the paper very wet. Therefore as soon as impressions appear blurred and squashed, the leather should be tautened and well lubricated with tallow.
Now we come to an important matter, namely, the correction of errors. It does not happen often that a drawing or inscription can be made entirely without error, and it would be a great imperfection in lithography if these mistakes could not be corrected at once.
Errors may be observed before etching or afterward. Different ways of making corrections are required.
It is very easy to make corrections before etching. If the error is observed as soon as it is made, while the ink still is wet, it may be corrected by merely wiping out the defect with the finger. If the ink is dry, oil of turpentine is required. In each case the ink must be well removed so that it will not resist the etching fluid later. If only tiny spots are defective they can be corrected by delicate use of a sharp eraser. Defects that need merely to be destroyed without drawing anything else in their place may be scraped off with a knife or with pumice stone.
After the plate is etched, errors demand treatments that differ according to whether a defect or blemish is merely to be removed, whether something else is to be drawn in place of the removed part, or if something has been forgotten and is to be added. The area of the correction also makes a difference.
If it is only a matter of removing small defects or places, delicate erasure will do. The same, or polishing with pumice, is done if the area is larger. Then the corrected spots must be coated with a mixture of gum and aquafortis, using a soft brush very carefully that it may not touch any of the sound places.
If something new is to be drawn in, the process is different. Ink-in the stone very clean, and coat it with gum and water that is very thin and delicate. Let it dry. Then scrape the defective places away very carefully or grind them away by rubbing with pumice stone. Coat the spots cautiously with soap-water or oil of turpentine and clean off again as thoroughly as possible. (This coating is not necessary in the case of a few isolated small lines or points.) Now draw in your new design with chemical ink, and as soon as this is dry, etch the corrections carefully with a small brush and then prepare with gum.
The third case, where something has been forgotten, is treated almost the same way. If it is only a very small thing, the stone need merely be scraped carefully. Then the drawing may be put in, preferably with a thicker ink. If the area is large, the stone must be ground where the design is to be added, coated with soap-water or oil of turpentine, and then treated as explained before.
When the stone has been corrected and prepared for printing, it can be used at once or set aside for some length of time. In the latter case it should be inked with a firm color and coated delicately with gum solution. Then it can be held as long as desired. Coating with gum solution is advisable not merely for storing away, but for every interruption of printing that lasts more than five minutes.
If a stone has stood longer than a day without being freshly inked, it must be wiped off first of all with gum solution and oil of turpentine, that it may take the color well, so that the very first impression may be perfect. During the progress of printing, the following points are important: Uniform distribution of water, the same of printing-color, frequent inking of the inking-roller, and the very greatest speed possible.
In the main points the brush process is like that of the pen. The chief difference is that it is not possible to make the brush strokes as strong as those with the pen. Therefore, brush work does not resist etching so well and must not be treated too powerfully. Much depends on the treatment of the brush and the consistency of the ink. The brush does not permit such a flow of ink as does the pen, and generally requires one that is more fluid. A good brush ink is made as follows:—
Mix two parts of pure white wax and one part of good tallow soap into a mass not larger than a hazel nut. The ink loses its good properties quickly and should be made fresh day by day. Mix the two materials with a thick knife on a lukewarm (but positively not warm) stone, separate into small parts and moisten with rain water. As soon as the water has softened the mass a trifle, add as much lampblack as will lie on two knife points and mix the whole mass together once more till it is thoroughly mixed and quite firm. When required, a bit of this is rubbed down in a clean saucer with rain water.
As a better flow of ink is needed for brush work than for pen work, it is evident that it would not be requisite to treat the stone with soap-water and oil of turpentine, as for pen work. However, it often pays to make certain fine lines with the pen, and therefore it is better to combine both processes and prepare the stone as for pen work. It is well, however, after drying the coating, to rub it very gently with dry sand, which will not make the pen strokes flow to any extent and still will prepare the stone so that it will take the brush strokes well and not make necessary such strong etching.
If a brush design is to be etched in high relief, for ease in printing or for durability, it must be etched only to the extent absolutely required at first. Then it must be prepared with gum and inked-in with good acid-proof color. Set it aside for a while, that the color may concentrate so that it will resist the acid well, and then etch the stone to the desired degree. After etching, wash with water, coat with gum and put aside to dry. Owing to this latter procedure any fine parts that may have been unduly affected by the acid will adhere to the plate anew and it can be printed then like a pen design.
If pen and brush work are to be combined on a stone, and absolute certainty is desired, that even the very finest lines shall not suffer from etching, the following process will serve:—
Over the cleanly ground plate pour a solution of weakened but pure aquafortis, about forty parts of water to one part of aquafortis. Repeat this several times. Then pour a great deal of water over the stone, to wash off all acid, and let it dry. Pen as well as brush work is easy on such a stone, by using the proper ink for each method. When the work is finished and dry, the stone is merely coated with gum solution. After a few minutes it can be inked-in with acid-proof ink and treated as described before.
The fat of the chemical ink penetrates the stone in dry form as well as in fluid form, and makes the plate receptive to printing-color. If the dry ink is cut into long pieces and sharpened, it can be used much like lead or black crayon. If the stone is ground very smooth, the work can be made quite fine and resembles that done with fluid ink. The crayon, however, wears away too quickly. If the stone is ground rough, so that instead of a polished surface it has one resembling rough paper, the crayon work appears as a mass of dots that are coarser or finer according to pressure with the crayon, and produce an effect similar to crayon designs on paper. As almost every artist and painter knows how to use crayon, no particular practice is required for working on stone, and there are no obstacles such as the difficulty of using the steel pen.
That crayon work on stone is capable of high perfection, and that it can represent the essentials of a painting in a manner scarcely to be excelled by the best copper-plate engraver, has been demonstrated by many successful productions. Add to this that in no other style can one work equally fast, either on copper or stone, and we see that the crayon method is a genuine advantage for the art.
For crayon work the stones must be uniform and hard. They must either be new, or, if they have been used, they must be ground so thoroughly that all traces of fat are destroyed and removed absolutely to a degree where it is certain that they will not appear again and take color, even if the stone is etched only lightly. As soon as the plates have been ground true, they must be grained by strewing some fine sand or powdered sandstone on them and rubbing in all directions with a small piece of limestone. The work can be done dry or wet. Soap-water is best. It gives the stone a handsome grain. Practice is demanded to get good results without scratching the stone. The artist must decide for himself what grain he needs. I think that it would be good if the artist himself were to grain the stone in varying degrees according to the need of his design. For instance, a coarser grain might be good for foregrounds.
As soon as the stone has been grained, it must be cleansed perfectly from dust and dirt. It is best to pour clean water over it and wash it with a clean rag. The dust and sand must all be removed, otherwise they will not let the crayon reach the stone where it is used delicately.
When the design is finished, it should be set aside for a day, that it may take good hold of the stone. It does no harm to let plates rest for years before etching. Etching must be done by pouring. Painting the etching fluid on is dangerous because of the danger of taking away fine spots. About one hundred parts of water are used to one part of aquafortis. Everything depends on not etching a bit more than necessary. It is best to etch the coarser parts specially with a small brush and stronger etching solution, and it is very good to wash the stone with clean water after etching and let it dry completely before coating with gum.
When the stone has been prepared, it should not be cleansed at once with oil of turpentine, but should be inked-in first with a light printing-color. Only after it has taken this well should it be cleansed of the crayon and treated to a firmer color. In the first inking-in there should be very little pressure with the sponge or wet cloth when dampening it, as the lightest parts of the design are easily rubbed away before they have taken color. If such parts should vanish, the easiest way to restore them is as follows:—
Coat the plate with gum solution and wipe with a clean dry cloth till it is perfectly dry. Then take a flat, knife-like instrument of steel, which is cleanly ground so that it has no nicks or other defects that might injure the stone. Scrape with moderate pressure to and fro over the defective places, but only so that it touches the elevated points and not the surface of the stone itself. Smear a little fat, such as linseed oil varnish, over it and wash this away again instantly with gum solution. Generally the parts all reappear very nicely when the stone is inked-in again. A second kind of correction is as follows: Ink the stone with firm color, wash it well with plenty of pure water and let it dry. Now redraw the lost places with crayon.
Printing crayon work is the most difficult of all lithography, but can be done perfectly if all necessary precautions are taken. These are mainly: (a) proper dampening of the paper; (b) perfect dampening of the stone;—too much meaning that the fine points will not take color well, too little making the stone smut easily; (c) good stretching of the leather, industrious lubrication, and an underlay of taffeta; (d) a good, finely mixed inking-color that will not shade off in printing and yet does not contain too much lampblack; (e) soft and well-dried ink-rollers; (f) proper tension of the press; (g) utmost possible speed in printing. The latter aids enormously, because the stone does not get so much time to dry out.
Aside from the spreading and running-together of the darker parts, one of the commonest faults of crayon work is that it is very liable to get a tone, which spreads over the whole design like a veil; or that the designs lose their firmness and appear "monotonic" because the shadings spread and thicken. The first fault comes from weak etching or from oil that was rancid when it was used to prepare the varnish. The latter fault makes the color adhere and smut the stone. The same fault is developed if the printing-color contains soap, which some printers mix into it for better adherence. It can occur also if the stone has lost its preparation owing to frequent cleansing and strong rubbing with a dry rag that is inky. Even strong rubbing with clean water can cause it if the rag contains fats.
As to the "monotonic" effect, it is frequent, and I have learned that it can be caused in two ways, namely, if the color is squashed continually during the print, which makes the stone sooty; or if the color spreads, as, for instance, during the night or during the noonday rest. The stone is prepared only on the surface. In the pen style, all lines are prepared on the sides also, so that they cannot spread because they are considerably more elevated than the crayon designs.
If a crayon design dries after printing and is not coated properly with gum, the color is liable to spread away from the design and give the plate the before-mentioned tone. Even if it is coated with gum, the color will spread, at least in the inner parts of the stone; and as soon as the very thin surface has been at all wiped away by rough usage, the underlying fattiness will appear gradually, and begin to take color.
Both faults of crayon work, namely, the taking of tone and the development of a "monotonic" condition, can be remedied by inking the plate for a while with a firmer color. If this does not help, the following must be resorted to: Ink-in the plate as well as possible, lay it in the etching-trough and pour over it very weak aquafortis once or twice. Then wash it with pure water and paint the gum solution over it. The etching must be done with great caution, with a solution so weak that the acid is scarcely perceptible. If the plate is to be saved at all without extensive corrections and re-drawing, this is the best way. If it is done correctly, it harms the design so little that I advise it even when the plate looks quite well, but has been standing very long after the first printing.
I have etched several crayon designs over again, and rather extensively, to make them more durable and facilitate printing, and with good success. This gives the further advantage that corrections can be made at the same time.
The correction of crayon designs, that have been etched already and used for printing, always has been so difficult a task that few have succeeded. This has led me to give the matter my best attention; and I hope that the following rules, based on many experiments, will show the way, at least, even if they do not produce absolute results.
When a copper-plate engraver has partially finished his plate, he can have a proof pulled to enable him to study his work. Then he can make corrections as he pleases,—an advantage that the stone worker has lacked hitherto.
To produce an impression that shall be faithful to all the beauties of a crayon design is a matter dependent on so many trivial details that of the many hundred crayon designs that have been produced by lithographers since the origin of the art, hardly one has realized the designer's hopes and ambitions. The commonest fault is that the more delicate parts of the design print too light and the heavier ones too dark, thus destroying the balance of tones. The lightening occurs because the finest parts of the design have lost their power of taking printing-color. The darkening occurs because the closely shaded parts flow together, either because the etching has not made enough white space between the points and lines or because they are squashed in the pressure of printing.
From this, two other faults may arise, that become visible after inking-in the plate: The first is the appearance of white dots, sometimes pretty large. The second is that black dots and smut-marks appear.
The white dots are caused by speaking during the work, and thus dropping spittle on the plate. If the spittle is mucous, the plate covers itself there with a fine crust that resists the chemical crayon so that it does not soak into the stone and is wiped away by the inking-in. If the spittle is fatty,—for instance, if one has eaten anything greasy,—the dots that appear will be black. The same results from touching the plate with fatty hands. Sometimes a whole picture of the fingers and skin will appear on the impression.
Let us suppose that after inking-in, a plate shows all these faults: the finest shadings vanished entirely, the darker places run together, white and black dots and smut-marks so that the plate has become useless in every respect. Can this be remedied? If so, how?
I answer that it can be remedied in every point; but that the artist himself must decide if it will not pay better to do the whole design anew.
The second question I answer as follows:—
Before everything else, it is necessary to remove all that should not be on the stone, all smut-marks and black dots; and where the design has darkened, white points or lights must be graved-in. To accomplish this, the stone is inked-in first with a firm acid-proof color, and over this with a lighter one. Then erase or grind away the dirt that is outside of the design and that would dirty the margin of the printing-paper. No erasing or grinding must be done within the design itself because then the grain would be destroyed and the necessary drawing could not be done as it should be. Therefore the faulty parts must be removed by engraving, with a more or less sharp needle of good steel, so that what remains looks quite like a good grain. A little practice will show that this work is not at all difficult and can be done quickly. Places that have run together can be cleared and made transparent and clean in a few minutes. If certain points have become too large, they can be corrected by engraving a white point in their centre or by engraving a line through them.
Here I must note that parts of crayon designs thicken sometimes because the crayon has slipped in drawing, without leaving traces perceptible at the time. If the etching is weak, it may happen easily that this place takes printing-color. Skillful engraving may not only correct the defect, but actually gives the design a beautiful tone and power such as cannot be easily produced by the crayon itself.
When the plate has been cleansed thus of all surplus and blemishes, weak aquafortis is poured over it several times and then it is coated with gum. After a few minutes it is inked-in with fairly firm color. Then it will be seen that the design is clean, but that all the parts that were too light are not darker, but perhaps even lighter, having been affected by the etching. To remedy this, coat the stone with gum solution and then wipe it off with a dry clean rag so thoroughly that only a thin film of gum remains behind. To judge this better, it is well to mix a little red chalk with the gum. When the plate is wholly dry, take a knife-like tool of steel as described before, and scrape the defective parts under moderate pressure, without injuring the elevated points of the design. Great care must be taken during this process to let no moisture, not even the breath, touch the stone, because that would produce the very opposite of what is aimed at. When all faulty places have been treated, a little tallow or linseed oil is smeared over the plate and then washed away well but gently with thin gum and water. If this manipulation has been done accurately, the lost parts of the design will appear when the plate is inked with a somewhat softer color.
Those who fear that they do not possess the skill necessary for this rubbing-up of the defective parts may attain the object by re-drawing them. The stone must be washed off first with a great deal of very pure water and the crayon must contain much soap. This kind of correction must be finished as quickly as possible and the stone should not be set aside for any length of time without a gum coating. If the corrections are extensive, it is better first to ink the stone well with acid-proof color and then to wash it in pure water and let it dry. Then if it is inked-in after the design is finished, and if weak aquafortis is poured over it and it is prepared with gum, it will keep for several months.
Slight blemishes, white specks, etc., can best be corrected by gentle touching-up with crayon during the proof-printing on the wet plate. It is understood, of course, that one can also work with pen or brush in a crayon design that has been already etched. Parts that are too dark can be made lighter by passing over them a few times with a brush dipped in weak aquafortis and then re-coating with gum.
These are about the best ways for correcting a crayon design that proves after etching to be imperfect.
I close with the following:—
(1) The tanners of Munich manufacture an inking-ball, made especially for printing, of sheepskin, such as I could not obtain in other places, like London, Offenbach, and Vienna. It is not white like alum-dressed leather, but yellowish, and the oil has not been completely washed out. I have had dogskin and thin calfskin worked in the same way and have found them even better, because of their greater durability. If a roller is covered with this leather, so that the side that was hairy comes outermost (not innermost as many do), it develops a decided property of taking-on color, probably because of its smoothness and elasticity. This aids much in spreading the color uniformly over the stone. The property is increased if the roller is dampened slightly before being inked; but on the contrary, if the stone is kept too wet, the constant moisture will gradually prepare the roller, so to speak, and it will take less color and let it go quickly, thus inking the stone badly.
If a roller has been used a long time, it loses its elasticity and softness and becomes useless for fine work. Still worse is a roller that has hardened from the drying of the ink. It is surprising to see what a difference it makes if one has worked for a time with a poor roller and then replaces it with a good one. It is almost impossible to believe that the new impressions come from the same stone. I am inclined, therefore, to believe that the quality of the ink-roller has more effect on good impressions of crayon and fine pen work than even the quality of the printing-color.
As stated, it is well to change rollers frequently, and it is wise to clean them with linseed oil or butter after use to keep them soft and tender. In working on crayon designs of superior value I advise the use of new rollers.
(2) It has been remarked before that the color of the stone often deceives the artist as to the values and proportions of his work and that the designs always look better on the soft-colored stone than they do on the glaring white paper. This observation led to printing on paper tinted like the stone, and the results fulfilled expectations. There were difficulties however. The very best quality of this paper is extremely dear, and other qualities had the property of dirtying the stone, on account of the coloring-matter used for tinting them. Therefore the attempt was made to print the design on white paper and to color it afterwards. Here, too, there arose many inconveniences, so that at last there came the thought of laying a yellow tint over the impression by means of a second printing. This method proved to be not only the most economical and quick, but it had the further advantage that the margins of the paper could be left white, thus enhancing the value of the design. Hardly had it been used with success a few times before Herr Piloty conceived the idea of printing the high lights into the design with white printing-color, so that the impressions would resemble actual drawings. My experiments toward that end did not result satisfactorily, because no white oil color will print well enough; and I proposed that the high lights be engraved into the tint plate and thus permit the original white of the paper to show. So there came that kind of crayon impression with one or more tint plates, which has become so popular that various art connoisseurs hold it to be the triumph of the lithographic art. To make and print these tone plates, I have thought out many ways; but as I am sure that they will suggest themselves to those who have grasped my text-book, I will describe only the best of them all.
Take a stone of good average quality, the best not being essential, and grind it as for crayon work with a grain not too coarse. When it is clean and dry, cover it uniformly with the following chemical ink, which must be laid on so thickly that it surely will resist the aquafortis sufficiently, yet not so very thickly that it will hinder the drawing-in of the lights later on.
The chemical ink for use on the tone plates is made of four parts wax, one part soap, and two parts vermilion. The two first materials are melted in a clean vessel over a moderate fire and then the vermilion is stirred in.
A piece of ink as large as a hazel nut is rubbed down in a clean coffee cup and then dissolved in rain water till it is just fluid enough to lie evenly and nicely on the plate when applied with a soft brush.
When the stone thus has been painted red, it must be permitted to dry thoroughly. When it is dry, a strong impression of the design is made on sized but well-dampened paper with a printing-color rather soft than firm. Before the paper has a chance to dry and thus to shrink, the red stone is placed in the press and the impression is laid on it face down. Use moderate pressure. The drawing will transfer itself to the red surface, but the paper will stick. Wet it with weak aquafortis till it is completely softened and permits itself to be removed. Care must be taken not to spoil the drawing by violent wiping and rubbing.
This method is easier if a special transfer paper is used. Coat well-sized, very clean paper with a thin paste of starch such as laundresses use for stiffening linen. This paper must not be dampened very much, because then it will not take the impression well. It also is removed from the tone plate by washing with weak aquafortis and it yields very easily, because the paste lets go of the color readily.
When the design has been transferred to the tone plate, take good iron instruments and remove the wax surface wherever the high lights are desired. As the stone is ground rough, the scraping will produce only small specks at first, because the instrument will touch only the relief points. The more the scraping proceeds, the deeper it will go, till at last one reaches the bottom of the coating and thus obtains a white light. Experts can so manipulate the tint plates that the lights will be graduated from the softest to the most glaring.
As soon as the lights are drawn in, the margins of the drawing are scraped the same way. Then the plate is treated to several washings of pretty strong aquafortis, about twenty parts of water to one part of aquafortis. After coating with gum, it is ready for printing.
The most important requisite for this printing is a good arrangement that will insure an exact register of the second impression with the first, that the lights may appear exactly where they belong.
To achieve this, the practice used to be to draw two register marks on the stone holding the original design, which were transferred to the tint plate with the rest of the design. When the first impression was made, the printed paper was cut away exactly at the marked points, and laid accurately, on the tone plate, being guided by the two marks there. This was effective, but it had the fault that the paper had to be trimmed off carefully for each impression and that the slightest inaccuracy spoiled the register. However, it is very useful for printing proofs.
It is far better to have a printing-frame that is so fixed that it will never shift its position in the slightest degree. To this is fastened a little movable frame that has two steel needles whose position is adjustable at will. Lubricate the leather inside with wax and lay a sheet of white paper on it. See that the tint plate is so fastened in the press that it cannot stir out of place. Make an impression and take care especially that the two register marks print off well. Now set the needles in the little frame so that they will be exactly over these two marks. If, then, an impression of the design is laid on so that the two guiding-marks on it come exactly under the two needles, it will, of course, register perfectly. Of course the little frame must be so adjusted that it can be folded back out of the way before each impression, and the printing-frame must hold the sheets of paper so that they cannot move. To color the tint plate, use a firm varnish tinted with umber, or any other color that will give the desired effect. New rollers are best, insuring a fine, even, unspotted tone.
(3) In rough-grinding the stones, it is difficult to prevent scratches and furrows caused by the coarse sand. No design of value should be made on such a stone, but if one is used, the defects should be touched up with chemical ink and a fine brush, as crayon will hardly do it.
(4) As the delicate places in crayon work are not durable, etching having the property of reducing the light portions and darkening the darker ones, I tried the method of drawing the lighter portions on a separate stone in rather stronger manner and printing from it with paler ink. The success was so great that I hope in time to produce true masterpieces with the aid of skilled artists, and here call attention to it in advance.
(5) After learning how to make a second impression over a first one, it is not difficult to pass on to printing with several stones and from that going on to color-printing. In the early days of my invention I tried color-printing with a crayon plate and had the best success by using stencils such as are used by the painters of cards. On oiled stiff paper I made as many impressions of a design as there were to be colors. Then all that was to be red was cut out from one stencil, green from another, and so forth. Then the stone was wetted, the stencil laid on it and the uncovered parts of the stones inked-in with the right color. After all the colors had been applied, I made the impression, which generally looked neat enough, but still resembled a sketchy drawing rather than a painting, because no color except black, zinc red, and dark blue permitted itself to be printed strongly enough. But by using several stones, each of which can be designed and treated according to the necessities of color, impressions can be made that resemble the English colored copper prints very closely, especially if the crayon and pen or brush methods are united.
(6) A stone plate may be etched so that it will have the roughness needed for crayon work. Grind it as clean and smooth as possible with pumice, pour aquafortis over it and coat with gum. Wash it well in water and dry with a clean cloth. Coat it very thinly but uniformly with tallow into which is mixed a little lampblack, so that one can see if the coating is perfectly even. With a small ball or roller covered with fine cloth, roll or pat the stone till it has a very uniform tone. Now pour a little diluted aquafortis on one end as a test to see if it penetrates uniformly through the fatty coating. Practice is needed to hit just the right thickness that the tallow coating must be. It must be thin, and yet sufficiently thick to resist the aquafortis somewhat, so that it yields only at those places where the roughness of the cloth on the roller has removed it more or less.
If the test is satisfactory, make a raised border of wax around the stone and pour the aquafortis solution on it. A solution of forty parts of water to one part of aquafortis is better than a stronger one because the stones are more equally attacked. As soon as the resulting bubbles are as large as the head of a small pin, the etching fluid is poured away quickly and replaced with pure water to get rid of the bubbles. Pour away the water and apply etching fluid again. Repeat this four or five times, according to the grain desired, and in the end wash the stone well with oil of turpentine to remove all fattiness. Then it must be washed with weak but very pure aquafortis, followed by a great deal of very pure water. After cleaning and drying very carefully with a clean rag, it is ready for use; and if the work has been well done, a grain will have been produced that is prettier and much more even than can be produced by rubbing with sand.
(7) The instructions given here teach how to draw on a stone that has been prepared beforehand with aquafortis and gum. This is not in the least inimical to the durability of the design if only the union of the gum with the stone has been destroyed again by washing afterward with diluted but pure aquafortis and every trace of this acid again has been removed by copious washing with pure water. If there is a considerable amount of the soap in the crayon, the good result will be greater than with an entirely clean stone, because, since it has already been etched twice, the etching after the design may be very limited, so that it is not harmful to even the most delicate shadings in the design.
(8) Some attempts made by me to etch crayon designs more powerfully than usual proved that the more delicate places would suffer, but if I rubbed them up with a flat knife as described before, they appeared again and I had the advantage that the whole plate was much better prepared than it is with weak etching.
(9) If a crayon plate is spoiled in printing through carelessness or lack of skill, the rules for remedying the trouble are the same as those named for pen work, and the judgment of the worker must decide which method is the most applicable. In general, it may be assumed that the best remedy for blurred spots is to draw them over again with crayon; and for smutted parts the best is to apply firmer printing-color, or to cleanse with oil of turpentine and gum and afterward ink-in with acid-proof ink, and then use light etching with weak aquafortis followed always by coating with gum and water.
III
TRANSFER AND TRACING
In the pen and crayon method all the lines that are to take printing-color are drawn directly on the stone with a fatty preparation. But lithography has a unique way of transferring to the stone a drawing or inscription that is first put on paper with the fatty substance. This is possible only for lithography, and I incline to the belief that it is the most important of all my inventions. It makes it unnecessary to learn reverse writing. Everybody who can write on paper with ordinary ink can do so with the chemical transfer ink, and this writing can then be transferred to the stone and manifolded indefinitely. In Munich and Petersburg this method has been introduced for government work. The measures adopted in council are written during the session by the secretary, with chemical ink on paper, and sent to the printery. Within an hour impressions are ready to distribute among the members. I am convinced that within ten years every European Government will have a lithographic establishment.
In war the method would have a great value. It would replace the field printery, and it permits greater speed and secrecy. The commander need merely write his orders himself and have them printed in his presence by a man who cannot read, to be sure that his plans will not be betrayed. The engineer officers can draw plans and have them circulated among the officers who need them.
Authors and scientists will find the method to be the means of circulating their works in manuscript very cheaply.
Even artists will respect the method when its gradual perfection enables them to draw their pictures on paper with ink or crayon and reproduce them.
Not from boastfulness, but from conviction of the importance of the method, have I thus recounted its advantages. I could fill a whole book with detailed explanations. I wish to gain friends for the method, that it may be improved to its ultimate degree by skilled artists.
The chemical ink used for the paper may be soft or firm. The paper may be specially prepared or not. The stone may be warm or cold. The design leaves the paper entirely and clings to the stone, or does so only partly. To describe all this would take too much space. I will describe only the method that I consider best, namely, a method under which the work is done with a soft ink, and transferred to an unwarmed stone. This is the quickest and surest, and has the advantage of not spoiling the original.
In a clean coffee cup rub down a piece, as large as a hazel nut, of the chemical ink described under the heading "Transfer Ink" in an earlier part of this work. Dissolve with rain water or soft river water. The amount of water is determined according to the need for fine or coarse work. In the latter case, the ink should be thinner, that there may not be too much ink in the design after it dries.
While the writing or design is drying, select a stone that either has not been used before or at least has been thoroughly ground off, and grind it down once more with pure and dry pumice stone without water, until it is certain that all parts of the surface have been rubbed down so thoroughly that the stone may properly be considered a new one. Clean away the dust with clean paper, fasten the stone in the press, examine the scraper to make sure that it is even, adjust the press for the proper pressure; in a word, do all that is necessary for good impressions. From this time on the greatest care must be taken not to touch the polished stone with as much as a finger, not to mention keeping grease and dirt away from it.
As soon as every point in the design on the paper is perfectly dry, wet it on the reverse side with a sponge dipped into weak but pure aquafortis until the paper is quite soft. Lay it between waste paper sheets for a time, to prevent it from pulling out of shape and to remove the excess moisture. It must be soft, but not wet, when the impression is made.
Lay the paper face down on the stone. On it lay two sheets of dry waste paper, then an equally large piece of taffeta, another sheet of waste paper and make the transfer print with a moderately swift motion of the press, which must have more tension than is used for ordinary impressions. The power of a lever press is insufficient for larger stones, and a cylinder press is required.
After a few minutes the stone is withdrawn from the press, the paper is lifted off and the stone permitted to dry for a minute. It is better if one can wait longer. Then put it into the etching-trough, and pour over it, quickly and only once, a clean but weak solution of one hundred parts of water to one part of aquafortis. It is necessary to be skillful enough to cover the whole surface with one application. Then the stone is washed by pouring pure water over it, and, if time permits, set aside to dry. If time is limited, the gum solution to prepare the stone can be put on at once. Now the transfer is on the stone, properly etched and prepared. To make clean impressions, however, the printing-color must first be rubbed on, then the stone must be inked-in with acid-proof color and after that undergo another etching, a trifle stronger.
To rub on the printing-color, rub a little acid-proof color into a piece of clean linen or cotton, so that it is well permeated but not thickly covered. Rub this rag gently to and fro over the transfer while the gum is still on it, till every part of the design is nicely inked. This rubbing-in of color is an important part of many of the processes that will be described later.
Now clean the stone well with water, ink-in with acid-proof ink, and etch it again as has been described several times. Then it is ready for printing. The last etching is not necessary if only a few impressions are desired. Transfer is applicable not only for pen designs but also for crayon. The crayon used for the purpose should be softened a little with tallow, or, if the harder crayon is used, the stone should be warmed when making the transfer. But it must not be inked-in or have color rubbed on, until it is quite cold again. For crayon transfer the paper used generally is fine drawing-paper. It must be wetted with somewhat stronger aquafortis that it may release the crayon more readily. The rest of the process is the same.
Besides these two methods, the transfer process can be used for all products of the book-printer's art, type as well as wood-cut. A freshly printed sheet can be transferred directly to a stone, especially if the printer has used our before-mentioned acid-proof ink instead of his ordinary printer's ink. To get a perfectly clear transfer it is necessary merely to see that the printer does not use too much overlay, which would stamp the type too deeply into the paper; and that before trying to transfer the printed sheet to the stone it is subjected to gentle pressure in the press to free it from all inequalities. To do this without at the same time risking any loss of ink which might subsequently weaken the transfer, the sheet is well wetted, laid on a clean, wet stone that has been prepared so that it will not have any inclination to take color, and subjected to a very slight pressure, the press being used with almost no tension. This makes the printed sheet beautifully even. Then if it is transferred to a stone properly prepared as described before, the transfer will be perfect.
Even old book pages can be freshened up and transferred. I have spoken already of those that are on unsized paper. With prints on sized paper the method is as follows:—
Make a paint-like mixture of fine chalk and starch paste. Thin it down with water and paint the sheet. Dip a bit of linen rag into a thin color made of thin varnish and tallow tinted with vermilion. Touch-up the wet paper with the rag till every bit of type has taken red color. Pour clean water over it and touch-up the paper everywhere with a ball of fine cloth stuffed with horsehair. This will remove all surplus color. Continue this till the type matter is only faintly red. Then the paper must be washed very thoroughly with many pourings of water and laid between waste paper sheets to remove all surplus moisture. The transfer and so on must be done then as in the other cases.
Good transfers can be made also from a copper-plate engraving if the copper-plate impression is made with our acid-proof ink. The ordinary copper-plate ink is not so good. It will be self-evident that designs on stone can be transferred and reproduced the same way.
The tracing process has the property in common with the transfer process that it transmits only a small amount of fattiness to the stone and requires subsequent rubbing-in of color to give it strength.
Coat a piece of thin and clean vellum paper with tallow and lampblack and wipe it off again as neatly as possible, so that there remains only a thin film, which will not smut the stone when laid face down, unless pressure is exerted. Now draw on this with a clean English lead pencil that contains no sand, or with a composition of lead, zinc, and bismuth, and the pressure will force the design on the stone and transfer its fat, which then penetrates the stone and will give impressions. In preparing a stone thus made, greater care in etching is necessary than even in the transfer process. Very weak aquafortis solution must be used.
The process is something between pen and crayon work. It is quite applicable for sketches and pictures that are to be illuminated.
IV
CONCERNING THE WOOD-CUT STYLE
For this purpose, the stone is coated completely with chemical ink on the places where this style is to be used. As soon as it is dry, the lights are drawn into it with a steel engraving-needle that is ground to a sharp or broad point according to requirement. Those parts that are to be very white, with fine lines and specks, are best drawn in with the pen. Thus the wood-cut style differs from the ordinary pen design chiefly in character and in the treatment of the darker parts. Its practice is much easier on the stone than on wood, and it can be combined with crayon work. Etching, preparation, and printing are the same as with other styles.
V
TWO KINDS OF TOUCHE DRAWING
One of these resembles the wood-cut style in method but in effect approaches copper-plate work. The stone is grained as for crayon, etched, prepared with gum, cleansed with water, coated well with soap-water, wiped, dried, and finally coated with a thin, colored covering of fat, by either coating with acid-proof ink or with hard chemical ink.
This first etching and preparation are required to prevent the fat to be applied afterward from penetrating too deeply into the stone, so that it may adhere only to the surface.
Now the design is made on it with a steel scraper. The manipulation is like that for making tint plates. It demands greater care, however, and better etching.
The completed design is etched (phosphoric acid being best) and coated with gum. A few drops of oil of turpentine are poured on and all the color is wiped away with a woolen rag, but without any rough rubbing. Then the plate can be inked-in with fairly firm acid-proof ink.
The second method would excel crayon work if it were perfected. I have advanced pretty far with it. It is an imitation of the ordinary wash drawing which is done with a brush and dissolved Chinese ink on paper.
The stone, which must be very clean and free from all fat, is grained, coated with soap-water, cleaned with oil of turpentine, and dried. Then a hard chemical ink, which may contain a little more soap than usual, or the ink described for brush work, is dissolved in pure rain water and used on the stone with a brush just as it would be used on paper.
When the design is finished and very well dried, the entire surface of the stone is rubbed gently with a fine cloth, in order to perforate the color with tiny holes everywhere. As it will perforate more readily in the parts where the ink has been laid on thinly, the succeeding aquafortis will eat through there more easily, and thus the etching will correspond nicely with the tones of the design. It is necessary, however, to know the strength of the acid and the resisting power of the ink very accurately. It is well to experiment and write down the best proportions. In any case, the etching fluid must not be too strong and the etching must not be done by pouring or brushing, but in the copper etcher's manner, by framing the stone with wax so that the fluid will lie on the stone. As soon as the resulting bubbles reach the magnitude of a pin's head, the fluid is poured off instantly and then poured on again till the bubbles reappear. How long this must be continued depends on the strength of the ink.
It is understood, of course, that the etched stone must then be coated with gum.
VI
THE SPATTER METHOD
This speedy and easily executed style surely will come into wide use soon. It is done as follows:—
The outlines of a design are laid on a stone prepared for pen work, by tracing. Then they are traced again, say four times, on sheets of paper. On each sheet everything that falls into the category of one of the four chief tones is cut out with a sharp penknife so that the four sheets are like the stencils of card painters. Now the chief lines of the design are made on the stone with chemical ink, using either brush or pen. Lay one of the stencils on it exactly, weight it that it may not move, and perform the operation of spattering.
This is done by dipping a small brush, such as a clean toothbrush, into chemical ink and scraping it with a knife so that the ink is spattered over the stone. Care must be exercised not to have too much ink in the brush, for fear of blots or over-large spattering. After practice it will be possible to produce such fine and uniform dots as cannot possibly be produced by the pen. After the desired grade of shading has been achieved, the stone is permitted to dry. Then the second stencil is laid on and the operation repeated till all have been used. If enough stencils are made, the whole design can be made by spattering. It is not necessary, however, to make many, as the design has to be finished up by hand afterward anyway.
This finishing-up is done first with the engraving-needle, which opens and decreases all dots that are too large, and then with the pen, which brings out the true proportions of the various tones.
VII
TOUCHE WITH SEVERAL PLATES
This really is only a process of using many tint plates. It makes splendid effects possible, equal to any produced by an artist with Chinese ink, and deserves the attention of all artists, especially as it is the easiest and quickest of all methods, even though it is a little circumstantial in the printing.
Draw the outlines of a design on the stone in chemical ink with pen or brush, and then make four, five, or six transfers on stone plates prepared for pen work. Register marks must be on the design. Now draw-in the darkest parts on the first plate, the less dark ones on the second, the lighter ones on the third, and so on till the whole design is finished. The work is best done with a brush. One or more of the stones may be designed with crayon; but the number of stones designed with ink must be greater, in order to make the grain of the crayon designs unnoticeable.
The etching is done as in pen work. For each stone the printing-color is chosen according to the tone of its design. Of course particular accuracy is vital; but the artist should not permit the apparent difficulties to frighten him, as he will see very soon after trial that no other method produces such beautiful results.
VIII
COLOR-PRINTING WITH MANY PLATES
This method, in which the various colors are drawn on several stones, either with pen or crayon, resembles the one just described.
According to treatment the impressions will resemble a painting, a copper-plate engraving in color, or an illuminated copper-plate engraving, if the color stones are used merely to lay colors over a design already printed in its entirety in black. The whole process is so like the preceding one that I need merely recount the colors that I have found serviceable for the purpose.
Red. Vermilion, red lake of cochineal, fine madder lake, and finally carmine if it is mixed first with Venetian turpentine before being combined with varnish, as otherwise it inclines to separate from the varnish and unite with water, staining the whole printing-paper red.
Blue. Berlin blue and mineral blue. Use only a small amount, sufficient for a few hours. These colors dry quickly, and, besides, make the varnish too tough, so that they must be thinned down from time to time with a little linseed oil. Fine indigo is very good, also a blue lake that is made of logwood and verdigris. This latter is not durable in sunlight.
I have had no success as yet with green or yellow.
Verdigris is difficult to manipulate because it smuts the stone easily and does not tolerate many mixtures. Schweinfurther green, one of the new colors, is much better in all respects, but not dark enough. Mixtures of yellow lake with indigo or mineral blue are not very durable. Golden yellow ochre with mineral blue or indigo does not produce a pretty green, and King's yellow mixed with blue is handsome but not durable. Neapolitan yellow and the newer chrome yellow with blue produce a green that is not dark enough.
I have obtained the handsomest and darkest green by printing the design blue first and then printing over it a yellow plate, so that the yellow lay over the blue. By using Berlin blue and fine ochre a fairly handsome color is produced. On account of its loss of color in water, ochre cannot be used unless Venetian turpentine is first mixed with the varnish.
A handsome and at the same time dark yellow is equally hard to obtain. Till a good color is invented, we must content ourselves with ochre, Terra de Sienna, Neapolitan yellow, mineral yellow or chrome.
This printing with various colors is a process for which the stone is superior; and it is susceptible of such perfection that in future true paintings will be produced by its means. My experience convinces me of this.
IX
GOLD AND SILVER PRINTING
This process is useful for decoration.
Those parts of the design that are to appear in gold or silver are drawn with chemical ink on a stone prepared for pen work. After the drawing is dry, it is etched and prepared in the usual way. The printing is done with a silver gray color of firm varnish, fine crayon and a very little lampblack. The paper must be entirely dry and very smooth. Soon after the impression has been made, the printed parts are covered with silver or gold leaf such as is used by gilders. It is pressed on slightly with cotton, that it may adhere, and then a sheet of paper is laid over it. Then the second impression is made, treated the same way, and so on.
No more impressions must be made than one can cover with silver or gold in two hours. If the ink is on the paper too long, it will draw in and not take the metal well. After gilding or silvering, the sheets must lie for some hours or till the next day, that the ink may take perfect hold of the paper, so that, in the succeeding pressing, it will not penetrate the metal and make it look sooty. The pressing is done by laying six or eight impressions on a clean stone under the press and passing them through as for printing, with the proper tension. This tension must be adjusted according to the firmness of the printing-color; therefore it is best to make test with one sheet. Then, if the metal does not adhere sufficiently, the pressure can be increased.
In the end all surplus gold or silver is removed by gentle wiping with clean cotton. This is easy, as it will have fastened itself only to the printed parts. If the impressions can be set aside for some days without being wiped, it is better, and there is not so much danger of injuring the brilliancy of the metal.
If gold and silver are to be printed on designs where there is other color also, or where there is black, the print on which the metal is to be applied must always be made first. Only when the sheets have been gilded or silvered, pressed, wiped, and cleaned, is the black design to be printed on from the next plate. That all this must be done with the register marks previously described is, of course, self-evident.
So I close my description of the Relief method; and I hope that I have made it all so clear that good results will come to all who follow my directions.
