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Prints are familiar to every one of us, and yet the subject of prints is strangely unfamiliar. If we look at a painting, a piece of sculpture, or at a monumental building, we know how these things came into being. Without any effort we can see in our mind’s eye the painter, with palette and brushes, applying the colors on his canvas, we can see the sculptor thumbing the clay model on the stand before him, with alternate gentleness and force, while the spectacle of stone-masons and bricklayers at work is a matter of daily occurrence. Likewise are we daily face to face with prints in our homes. They are familiar objects that have always been there; we are so used to them that we hardly see them. But have we ever conjured up, in our mind’s eye, the vision of an engraver, or etcher, or lithographer at work making the print which is so familiar to us? It is a world, indeed, this field on which the energies of thousands upon thousands of men have been expended, expressive of the thoughts of great masters, expressive, yes, eloquent, of the changing mental attitude, the changing customs and interests of successive periods. There is no field, I am tempted to say, in all the realm of art, more comprehensive, more broadening than this subject of prints. In order fully to appreciate the phases of its development, we must find out, first of all, what a print is, and how it is made.

The term “print,” as we use it here, applies to any design conveyed upon paper or any similar substance by means of pressure, usually in the printing-press. Prints are not all produced in one and the same manner;—if this statement should prove surprising, just open any magazine on an illustration page; then place beside it, for comparison, a new dollar bill. Notice the even tone of black in the magazine illustration and the intensity of the black, sharp-cut, metallic lines of the head on the bill. It is quite evident that these two examples have been produced by different means; the magazine illustration shows that the inked lines and dots which constitute the picture have been brought upon the paper with considerable pressure: the ink is embedded into the paper; whereas, if the bill is new, you will notice, upon close inspection, that the ink of every line and dot lies upon the surface of the paper. Pass your finger lightly over some of the heavier lines, and if your finger-tips are sensitive, you will distinctly feel these ridges of ink. Why this difference? Because human ingenuity has devised several ways of obtaining an impression. There are three such possibilities, which divide the graphic arts into three main groups, namely:—

Relief processes: Woodcut, wood-engraving;

Intaglio processes: Engraving, dry-point, mezzotinting, and the etching processes;

Planographic processes: Lithography, and its derivatives.1

1 In order to keep the subject as simple as may be, we will leave aside that vast array of modern processes based upon photography, and therefore known as photo-mechanical processes (half-tone, photogravure, and the like) and devote our attention to the hand processes only.

Examples from two of these main divisions have just been under discussion, the magazine illustration being a relief print, the bill an engraving on steel, consequently intaglio. Let us now devote a few moments to their technical features, taking first the oldest of all the processes, woodcut.

If we take a block of wood, nicely planed, finish its face with sandpaper, and cover it with printer’s ink, an impression from that blackened surface would naturally be an unbroken, rectangular patch of black. Now we take a knife with a strong, short blade, a woodcutter’s knife, and with two slanting cuts we take out a thin long sliver from the middle of this blackened surface of wood. The result of an impression will now be a black surface with a white line where we have cut away the wood. Another two cuts parallel with the first will result in another white line, or rather we shall now have a black line, with a white space on either side, the black line being the ridge of wood standing between the two pieces which we have cut away. Could anything be simpler than this working recipe?—wherever black is wanted, leave the wood standing; where you need white, cut away the wood. The same theory applies to wood-engraving, with some changes in material and implements. The wood-engraver uses cross-grain blocks of the hard boxwood, instead of planks of cherry or pear wood, and on this hard surface the graver replaces the knife. The graver—most useful of tools—is a long, thin, diamond-shaped bar of steel, ending in a blunt point with cutting edges; its wooden handle fitting the palm of the hand. The graver is pushed forward and ploughs with great precision across the block or plate, cutting lines of any degree of delicacy or boldness. Like the knife, it removes the wood, consequently leaving a white line or dot wherever it has passed. Hence the term “white-line engraving,” often used for wood-engraving.

When we turn to the second great division, to the intaglio processes, we find that the recipe of the woodcut has to be just reversed to fit this new proposition. Consult the diagram of the three possibilities of printing; the cross-section of the relief-block presents a series of flat-topped ridges with valleys between them. The tops of the ridges print, the valleys are the spaces which are to appear white in the impression. The second figure, a cross-section of an intaglio plate,—an engraving on copper we will say,—shows no hills and vales, but a flat surface with a number of V-shaped cuts filled with ink. When engraving on a copper plate, we cut with the graver into the metal every line of our design that is to appear black. Wherever we want a white space we are careful to leave untouched the polished surface of the plate. Having completed the cutting-in (engraving) of our design, the plate is covered all over with printing-ink, and this is rubbed thoroughly into every furrow which we have cut, so that they are all filled flush with the surface. The surface of the plate is wiped clean. An impression taken from the plate so prepared will show us a black line for every furrow we have cut. Small wonder that the lines on the dollar bill were perceptible ridges of ink, since all the ink in the furrows of the plate is now on the surface of the paper. The theory of the intaglio processes is plainly this: wherever you want black in your design, cut lines or dots into the plate; wherever white is needed, leave the smooth surface of the plate untouched. Based upon this formula, the different intaglio processes produce their blacks in different ways; in dry-point engraving, for instance, the design is scratched into the metal by means of a sharp needle-point, the etching-needle. In tearing through the copper the needle leaves a jagged ridge of copper standing on the sides of each line, this “burr” retains some ink after the plate has been wiped clean, and gives to the dry-point line its peculiar velvety, slightly blurred appearance. The mezzotinter begins his work by roughening the whole surface of the plate with the “rocker” into myriad indentations and tiny projecting teeth of copper. The plate in this condition prints a uniform, velvety black, the deepest tone obtainable. Now by scraping away the little teeth of copper more or less completely, the design is modeled at will in varying half-tones. The high lights are obtained by burnishing the copper quite smooth again. The etcher, instead of cutting the lines of his design into the copper, trusts to the corroding action of powerful acids. Covering his plate with an acid-proof etching-ground, he draws his subject with the etching-needle, using just sufficient pressure to cut through the thin film of ground and lay bare the copper. The plate is then put into an acid bath which eats away the metal wherever a line has been laid bare. The ground is then washed off with a suitable solvent, and the plate printed. There are a number of processes based on etching, like aquatint, crayon manner, stipple, soft-ground etching, and others, but a review, however brief, of all these kindred devices does not lie within the scope of these pages.

We have now reviewed the relief processes, both dependent entirely on hand work, and the intaglio processes, engraving, dry-point, mezzotint, likewise relying upon manual power to prepare the plate for printing. In the etching group of intaglio devices, a chemical factor is called upon to lessen and accelerate the work of the hand. The last group to be considered, planographic processes, is based entirely upon chemical and physical action. The drawing to be reproduced is made with fatty crayon or ink upon a slab of a special variety of limestone; the stone is then treated with acidulated water, and with gummed water. As a result, when the stone is moistened, all those parts which have been drawn upon reject the water, but have an affinity for printing-ink, while the portions not drawn upon have an affinity for water and reject printing-ink, as long as they are kept moist. Neither by ridges nor sunken furrows, just from one plane surface,—hence the term “planographic,”—merely by the enmity of water and fatty ink are these lithographic impressions obtained. Plates of metal are often substituted for stone (zincography, algraphy), but the process always remains the same.

It goes without saying that each of these three possibilities of printing necessitates presses of appropriate construction; thus, in the so-called platten press, the pressure is exerted vertically upon the block by the flat metal plate which comes down upon it, on the same principle as in the letter-press familiar to us all. All intaglio plates are printed in roller presses, in which the plate, laid on an iron bed, passes between two rollers, one above, one below, as in a clothes-wringer. The lithographic press, finally, has a traveling bed, which passes under a stationary flat piece of wood. During its passage under this wooden bar, the paper is firmly pressed down upon the stone, which would be crushed in the other types of presses.2

2 Lithographs made on metal plates may be printed in an intaglio press as well.

After this summary review of the technique of prints, let us consider, with what brevity we may, the great phases of development of the graphic arts.