AS illustrators, or would-be illustrators, your work is not at an end with the completion of your drawings; you must look after them while they are being engraved, and you should see them through the press. From the time you are given a commission to illustrate a subject until the printed result is in the hands of the public, the work in all its stages should be the object of your untiring attention. It is true that at present the fact that you take an interest in your profession will be counted against you in some quarters, for should you happen—as is not unlikely—to know more of drawing, engraving, and printing than the art editor, the engraver, or the printer, your suggestions will not be received with enthusiasm, nor your criticisms with delight. Suggestions mean changes, and criticism means objections to the routine way of doing things. Then you may not feel a great interest in the scientific side of your work, yet chemistry plays an important part in illustration. The mechanical reproduction of drawings is based entirely on chemical action, and you must know something of this matter if you would get good results.
But let us consider the whole subject. Drawings in line were originally, in the fifteenth century, reproduced by wood cutting;[1] that is to say, the drawing was made in line with pen, point, or brush on the side of a plank, and all those portions of the block which were not drawn upon were cut away with knives and chisels, the design only remaining in relief; this relief was dabbed over with ink or paint, and a piece of damp paper was laid on it. The back of this paper was rubbed, burnished, or pressed on to the inked surface of the block and took up the ink from it; on removing the paper an impression in reverse of the inked block was found on the under side of it. And this was the method, with improvements, employed in printing from type, for three hundred years.
[1] Of course I shall refer to metal engraving in another lecture.
About the beginning of this century the design began to be drawn upon the end of a block of box-wood—a cross section of it—and the parts left blank were cut away with gravers, tools used by engravers in metal, or else lines were engraved on the surface of the block, which printed as whites in the blacks; the grain of the cross section of box-wood was firmer and finer, and with the gravers more delicate lines could be engraved and more true results obtained; and at the same time continual improvements were being made in the presses, steam being substituted for hand power, and the manufacture of paper and ink totally revolutionised.
These methods were employed until about 1865, when, instead of the drawings being made by the artists on the block of wood, they began to be drawn on paper in line, and then photographed on to the wood. This was a great improvement, because the artist could now make his designs of any size he wished and have them photographed down to the required dimensions and reversed for him: the mere reversing in many cases was both tedious and uninteresting.[2]
[2] If the drawing is a portrait of a place, it must be reversed on the wood or metal in order that the print may appear as the original does in nature.
The final step which brings us to the present, though not by any means, I am sure, to the end of the chapter, is the superseding of the woodcutter or wood engraver in line, by the mechanical engraver in metal or gelatine.
Now you may do your drawings, if you wish, in line with a pencil or brush upon the prepared piece of box-wood, and the engraver may cut away all those portions of the wood-block which you have not touched, remembering always that though you draw freely he must engrave laboriously, and the more free your drawing becomes, the more complicated must his engraving be. So when you make a sketchy drawing on wood, none but the most accomplished engraver can retain that look of freedom and sketchiness; if the lines of the drawing become really complicated, in cross hatching, for example, he cannot follow them, he must suggest them. Hence, unless the engraver really loves this sort of work, it is but drudgery, and the better the reproduction the more skilled labour wasted.
Now photography has changed all this. A photograph of the drawing, of the required size it is to appear on the printed page, is taken. The drawing may be enlarged or reduced to this size, and the negative thus obtained is placed in reverse in a photographic printing frame, in contact with a sensitised zinc plate, coated with a thin film either of albumen or bitumen, or it may be that a gelatine film is the material used for printing on. In the first method the albumen coated piece of zinc is removed from the printing frame as soon as the photographic print has been made; it is then coated with ink and placed in water, the albumen and ink upon it adhere to those parts of the zinc which have been exposed to light, and may be washed off the other parts, thus leaving the picture on the zinc in ink. By the bitumen process the picture is printed in the same way: the plate is placed in a bath of turpentine, the picture appears on the zinc, and the bitumen dissolves off the other parts.
If these two prints are now covered with powdered rosin, gum, and ink, they may be placed in a bath of nitric acid and water, and the exposed parts bitten or etched away. This is a most interesting and delicate process, and success depends in good work more upon the skill and artistic intelligence of the etcher than the chemicals used. The object is to remove all the whites as in wood engraving, half remove the greys, and leave the blacks. After the zinc has been bitten a short time it is taken out of the bath again, covered with gum, resin and ink to protect it from the acid, heated, when the protecting mass melts and runs down the sides of the bitten lines and protects them also; this process is continued until the block is sufficiently etched. When the exposed parts are all eaten away the picture appears in relief. This occupies a few hours, maybe but an hour or less. When completed, the zinc picture is mounted upon a piece of wood, to make it the same height as the type, placed in a printing press and copies are made of it, or from electrotypes or stereotypes, at the rate of from twenty to 20,000 an hour. This is, I hope, an intelligible outline of the photo-engraving process; every mechanical engraver has some variation which is his carefully guarded secret. The blocks may be of zinc or copper or other metal, and all sorts of chemicals are used. But I cannot too strongly impress upon you that good work in mechanical engraving is only to be obtained by artistic workmen; still, remarkable results are to be seen all about, even in the cheapest prints. But the very best process engravings are produced only by men who are artists and care for each block. In the case of the best engravers they will know better than you which process to use, and there is no more necessity for you to try to tell a mechanical engraver how the work is to be done, than for you to tell a wood engraver what tools he shall work with. Bad drawings may look better by one process than another, and good illustrations may be spoiled more by one method than another. But every intelligent engraver will try again and again until he gets the best result he can.