MEZZOTIN'I'O, in engraving, a peculiar mode of engraving designs of any description upon pities of copper or steel, with the view of obtaining impressions therefrom. In this style of engraving, which essentially differs from every other, the surface of the plate is first indented or hacked all over by the action of an instrument something like a chisel, with a toothed or serrated edge, called a cradle, or mezzo tinto grounder. This tool being rocked to and fro in many directions, indents or barbs the plate uniformly over its face, and produces what is called the mezzotinto grain or ground.
The barb, or nap, thus produced retains the printing ink; and if in this state of preparation an impression were taken from the plate upon paper, it would be uniformly of a deep black colour.
The directions, or ways, as they are technically called, given to the grounding-tool, are determined by a regulated plan, and for this purpose an ingenious sort of scale is used which enables the work man to pass over the plate in almost any number of directions without repeating any one of them. The mezzotinto ground being thus laid, it is at this period that the business of the artist properly commences. Having traced or drawn, with a pencil or other instrument, his out line upon the paper (unless indeed, as is sometimes the case, this should have been etched by the ordinary process, previous to the mezzotint ground having been laid), he proceeds to remove the nap or ground, in conformity with the design, from all those parts which are not intended to be perfectly black in the impression. The instruments required for this purpose are scrapers and burnishers ; with the. former he scrapes away more and more of the ground in proportion to the brightness of the light, and the burnishers are used to produce perfect whiteness where it is required, as the high lights on the fore head or tip of the nose, or white linen in a portrait, &c. As the work proceeds it may be blackened with ink, applied with a printer's ball or otherwise, to ascertain the effect ; after which the scraping may again be proceeded with, the artist taking care always to commence where the strongest lights are intended to appear.
The great facility with which mezzotintos are executed, as com pared with line-engravings, will be obvious, seeing that it is much easier to scrape or burnish away parts of a dark ground corresponding with any design sketched upon it, than it is to form shades upon a white ground by an infinite number of strokes, hatches, or points, made with the graver or etching-needle. Herein consists the leading difference between this and all other modes of engraving ; for while the process in each of these is invariably from light to dark, in mezzo tiuto it is from dark to light ; and even the very deepest shades are produced, as we have seen, before the design is commenced. The
characteristic or distinguishing excellence of mezzotinto engraving would seem to consist hi the richness, depth, mellowness, and harmony of its shadows, the obscurity of which especially sympathises with fine effects of chiaroscuro.
Having mentioned what we conceive to be the characteristic excel lence of mezzotint°, namely, the richness and profundity of its shadows, it is but fair to add that its chief defect seems to he a corre sponding poverty in the lights ; and this objection will be felt to have much weight, when it is considered that it is to the lights in a picture that the eye is invariably attracted. On the lights therefore the line engraver displays all that delicacy and beauty of line which agreeably irritates the eye and compensates for the absence of colour, by render ing the lights more interesting than the shadows. The lights in mezzotint°, on the contrary, where they occur in broad masses, have been ever felt by the judicious to be comparatively cold and poor. This objection has been partly obviated by a judicious admixture of etching with the mezzotint°, which, by enriching the lights, has done much towards uniting the energies of both styles. Objection has also been taken to mezzotinto on account of the limited number of good impressions which an engraving in this style would yield, in conse quence of the very superficial nature of the ground. A work of this sort, however, was always more susceptible of renovation by retouching than one produced by any of the other modes ; and the introduction of steel plates, which are now commonly substituted for those of copper, has removed the objection almost entirely, a very large number of good impressions being thus ensured without the necessity of retouch ing. A copper-plate will seldom furnish above one hundred and fifty good prints before requiring retouching. When the plate begins to wear, the practice is to work it over again, partially, with the cradle; and afterwards to again have recourse to the scrapers ; and in this way impressions of fifty at a time may be taken ; so that by alternately retouching and printing by fifties, live hundred prints are frequently obtained from one copper-plate. But from a steel-plate eight or ten times that number may be obtained. The process is the same in the one case as in the other, but heavier pressure on the grounding-tool is requisite on a steel-plate. A greater number of ways also is desirable, and these may be effected without rendering the subsequent engraving liable to more rapid deterioration, as would be the case upon copper. As many as ninety ways are frequently used on steel, while the number on a copper-plate varies from twenty-four to forty, which latter is rarely exceeded.