We just mention by way of note the process which produced those rare specimens called "empreintes en pâte." All specimens of this work are anterior in date to the sixteenth century, and belong less strictly to art than to industry, as the process only consisted in producing on paper embossed designs strongly suggesting the appearance of ornaments in embroidery or tapestry. To produce these inevitably coarse figures a sort of half-liquid, blackish gum or paste was introduced into the hollow portions of the block before printing. On the block thus prepared was placed a sheet of paper, previously stained orange, red, or light yellow, and the paste contained in the hollow places, when lodged on the paper, became a kind of drawing in relief, something like an impasto of dark colour. This was sometimes powdered with a fluffy or metallic dust before the paste had time to harden.
Though simple enough as regards the mere process, in practice line engraving demands a peculiar dexterity. When the outlines of the drawing that is to be copied have been traced and transferred to a plate usually made of copper[1] the metal is attacked with a sharp tool, called the dry-point. Then the trenches thus marked out are deepened, or fresh ones are made with the graver, which, owing to its shape, produces an angular incision. The appearance of every object represented in the original must be reproduced solely by these incised lines: at different distances apart, or tending in various directions: or by dots and cross-hatchings.
Line engraving possesses no other resources. Moreover, in addition to the difficulties resulting from the use of a refractory tool, we must mention the unavoidable slowness of the work, and the frequent impossibility of correcting faults without having recourse to such drastic remedies as obtaining a fresh surface by re-levelling the plate where the mistakes have been made.
Etching by means of aquafortis, originally used by armourers in their damascene work, is said to have been first applied to the execution of plates in Germany towards the close of the fifteenth century. Since then it has attracted a great many draughtsmen and painters, as it requires only a short apprenticeship, and is the quickest kind of engraving. Line engravers have not only frequently used etching in beginning their plates, but have often employed it, not merely to sketch in their subject, but actually in conjunction with the burin. Many important works owe their existence to the mixture of the two processes, among others the fine portraits of Jean Morin, and the admirable "Batailles d'Alexandre," engraved by Gérard Audran, after Lebrun. But at present we are only occupied with etching as practised separately and within the limits of its own resources.
The artist who makes use of this method has to scoop no laborious furrows. He draws with the needle, on a copper plate covered with a coating of varnish, suggestions of form as free as the strokes of pen or pencil. At first these strokes only affect the surface of the copper where the needle has freed the plate from varnish. But they become of the necessary depth as soon as a certain quantity of corrosive fluid has been poured on to the plate, which is surrounded by a sort of wax rampart. For a length of time proportioned to the effect intended, the acid is allowed to bite the exposed parts of the metal, and when the plate is cleaned proofs can be struck off from it.
With the exception of such few modifications as characterise prints in the scraped or scratched manner, called "sgraffio," and in the stippled manner, the methods of engraving just mentioned are all that have been used in Europe from the end of the Middle Ages up to about the second half of the seventeenth century. We need not, therefore, at present mention more recent processes, such as mezzotint, aquatint, &c., each of which we shall touch upon at its proper place in the history of the art. Before proceeding with this history, let us try to recollect the facts with which we have prefaced it; and, as chronological order proscribes, to differentiate and classify the first productions of relief engraving.
However formal their differences of opinion on matters of detail, technical writers hold as certain one general fact. They all agree in recognising that the methods of relief engraving were practised with a view to printing earlier than the method of intaglio. What interval, however, separates the two discoveries? At what epoch are we to place the invention of wood engraving? or if the process, as has been often alleged, is of Asiatic origin, when was it brought into Europe? To pretend to give a decisive answer to these questions would be, at least, imprudent. Conjectures of every sort, and even the most dogmatic assertions, are not wanting. But the learned have in vain evoked testimony, interpreted passages, and drawn conclusions. They have gone back to first causes, and questioned the most remote antiquity; they have sometimes strangely forced the meaning of traditions, and have too often confounded simple material accidents with the evidences of conscious art properly so called. Yet the problem is as far from solution as ever, and, indeed, the number and diversity of opinions have up till now done little but render conviction more difficult and doubt more excusable.
Our authorities, for instance, are not justified in connecting the succession of modern engravers with those men who, "even before the Deluge, engraved on trees the history of their times, their sciences, and their religion."[2] Nor is the mention by Plutarch of a certain almost typographical trick of Agesilaus, King of Sparta, excuse enough for those who have counted him among the precursors of Gutenberg. It is by no means impossible that Agesilaus, in a sacrifice to the gods on the eve of a decisive battle may have been clever enough to deceive his soldiers, by imprinting on the liver of the victim the word "Victory," already written in reverse on the palm of his hand. But in truth such trickery only distantly concerns art; and if we are to consider the Greek hero as the inventor of printing, we must also allow that it has taken us as long as eighteen centuries to profit by his discovery.
We shall therefore consider ourselves entitled to abandon all speculations on the first cause of this discovery in favour of an exclusive attention to such facts as mark an advance from the dim foreshadowing of its future capabilities to the intelligent and persevering practice of the perfected processes of the art. We shall be content to inquire towards what epoch this new method, the heir of popular favour, supplemented the old resources of the graphic arts by the multiplication of engravings in the printing press. And we may therefore spare ourselves the trouble of going back to doubtful or remote information, to archæological speculations, more or less excused by certain passages in Cicero, Quintilian, and Petronius or by a frequently quoted phrase of Pliny on the books, ornamented with figures, that belonged to Marcus Varro.[3]
Moreover in examining the historical question from a comparatively modern epoch only, we are not certain to find for ourselves, still less to provide for others, perfectly satisfactory answers. Reduced even to these terms, such a question is complicated enough to excuse controversy, and vast enough to make room for a legendary as well as a critical view of the case. Xylography, or block printing, which may be called the art of stamping on paper designs and immovable letters cut out on wood, preceded without doubt the invention of printing in movable metal characters. Some specimens authentically dated, such as the "St. Christopher" of 1423, and certain prints published in the course of the following years, prove with undeniable authority the priority of block printing. It remains to be seen if these specimens are absolutely the first engraved in Europe; whether they illustrate the beginning of the art, or only a step in its progress; whether, in one word, they are types without precedent, or only chance survivals of other and more ancient styles of wood engraving.