ON COPPER.
The art of engraving on copper plates, for impressions, is alleged to have been invented by Peter Schoeffer, one of the early printers, and son in-law of John Faust, about the year 1450. The honour of this invention is also claimed by a Florentine goldsmith of the name of Finguires, who dates his invention in 1540. This artist having used liquid sulphur to take an impression of some chasing and engraving he had made, observed a blackness produced by the sulphur left in the deepest parts of his work, whence he obtained an impression on paper.
But we have no hesitation in giving the preference to Schoeffer, who, we have previously remarked, was of an ingenious turn, and assisted Guttenburg in producing moulds for casting his types; in addition to which, some of the books printed by him are ornamented with head and tail-pieces, with other rude attempts at engraving; and likewise because Schoeffer’s claim to the honour was acknowledged before Finguires was born.
Of engraving there are various kinds; that called by connoisseurs, the legitimate mode of engraving, is what is termed the line or stroke mode. Numerous have been the British artists who have excelled in this style, in affording the means of multiplying our graphical productions.
The next species of engraving we will notice is called the stipple, or chalk style,—imitations of chalk drawings. Portraits and historical pieces are executed in this style, which the celebrated Bartolozzi brought to perfection.
The third species we will mention, cannot properly be called engraving; the effect is produced by scraping and rubbing; this kind is called chiaro obscuro, or mezzotinto; producing prints which have the effect of Indian ink drawings.
A fourth species of engraving is what is commonly used for landscapes, which produces an effect like a pencil water-colour drawing; which is called aquatinta.
In all of these kinds of engravings upon copper the artists find the sulphuric acid, or aquafortis, a most powerful agent. Sometimes, indeed, it is suffered to execute the whole of the process of the graver, especially when it is called an etching.
For the same reasons as those mentioned with regard to wood engravers, we shall abstain from naming any of the very eminent artists now living.
We have already observed the mode of obtaining similar effects from wood and copper, are opposite to each other. The manner in which impressions from wood engravings are obtained, has likewise been noticed; and it remains that we observe the mode by which impressions are obtained from copper-plates. The plate is covered with appropriate ink; the surface is then carefully cleansed, leaving ink only in the excavations or lines in the copper. The plate and paper are passed through a roller press of great power, the roller being covered with a blanket, which presses the paper into all the crevices of the plate, and brings away the ink there deposited.