We shall now proceed to explain the methods of executing different descrip tions of engraving. The graver, an in strument of steel, is the primary object for engraving on copper ; it is square for cutting of broad lines, and lozenge for the finest, and must be tempered to that exact state, which will prevent the point from breaking or wearing by its action on the metal ; to obtain this state, is is customary to heat it when too hard on the end of a red hot poker, till it assumes a straw co lour, and then cool it in oil ; if held too long, it will become blue, soft, and use less, till the process of tempering the steel is renewed. As it is possible a graver may be of the proper degree of solidity, except in some i inconsiderable part, it would be well to rub it on the oil stone till that is ascertained. The graver is inserted in a handle of hard wood, re sembling a pear with a longitudinal slice cut off, which is to enable the artist to use it as flat on the plate as his fingers and thumb will permit. In order to pre pare this instrument for cutting a clear smooth line, great care must be taken, in sharpening it, that the original general form should be preserved, by laying the sides flat upon the oil-stone, and rubbing them so as not to round them in the least, after which the graver is to be held sloping towards the person, and rubbed thus till the point is extremely sharp ; besides these precautions, it will be necessary that the point should not be exactly in a right line with the lower part of the gra ver, but a little higher, that it may not press too deep into the copper. In rub bing the sides of the graver, the usual manner has been to confine the right arm close to the side; placing the fore finger of the left hand on the upper side of the tool when on the stone. This instrument is used for finishing the imperfections discoverable in etchings, and exclusively in engraving writing.
The scraper is a long triangular piece of steel, tapering gradually from the han dle to the point ; the three edges produc ed by this form, being sharpened on the oil-stone, are used for scraping off the roughness occasioned by the graver, and erasing erroneous lines.
The burnisher is a third instrument of steel, hard, round, and highly polished, for rubbing out punctures or scratches in the copper. The oil stone has been al ready mentioned ; to those may be added the needle or dry point for etching, and making those extremely fine lines which cannot be done with the graver.
Cushions made of soft leather, and fill ed with fine sand, hence called sand bags, are required for the support of the plate in engraving, which, from their cir cular surface, permit the copper to turn with ease, and facilitate the cutting of those true curves composing the shading of most subjects. The oil rubber and charcoal are necessary for polishing the plate.
Every thing depends upon the free use of the graver, therefore the utmost care must be taken to hold it properly, by pre venting the interposition of the fingers be tween the graver and the plate, with the fore finger on the upper angle, which enables the artist to conduct it parallel with the substance engraved, thus pre venting the point from entering deeply, and impeding the progress of the tool.
To engrave well requires good materi als, though those are nearly confined to two, the graver, and the best copper; the latter should be free from flaws, small punctures, well hammered to close the pores, and polished to such a degree as to be free from the slightest scratches.
To trace the design intended for en graving accurately on the plate, it is usual to heat the latter sufficiently to melt white wax, with which it must be cover ed equally and thin, and suffered to cool ; the drawing is then copied in outlibes with a black-lead pencil on paper, which is laid with the pencilled side upon the wax, and the back rubbed gently with the burnisher, which will transfer the lead to the wax. The design must next be traced with an etching needle through the wax on the copper, when, on wiping it clean, it will exhibit all the outlines ready for the graver.
The table intended for engraving on should be perfectly steady, and the sand bags placed equally firm, in cutting or curved or undulating lines, the graver must be held still, or moved, to suit the turning of the plate with the left hand ; but when straight lines are intended, the plate is to be held stationary, and the graver urged forward with more or less pressure, according to the thickness of the line. Great care is necessary to carry the hand with such steadiness and skill, as to prevent the end of the line from being stronger and deeper than the commencement ; and sufficient space must be left between the lines, to enable the artist, to make those stronger, gradu ally, which require it. The roughness or burr occasioned by the graver must be removed by the scraper, the lines filled by the oil-rubber, and the surface of the copper cleansed, in order that the progress of the work may be ascer tained.
If any accident should occur, by the slipping of the graver beyond the boun dary required, or lines are found to be placed erroneously, they are to be ef faced by the burnisher, which leaving deep indentings, those must be levelled by the scraper, rubbed with charcoal and water, and finally polished lightly with the burnisher.
As the uninterrupted light of the day causes a glare upon the surface of the copper, hurtful and dazzling to the eyes, it is customary to engrave beneath the shade of silk paper, stretched on a square frame, which is placed reclining towards the room, near the sill of a window.
Such are the directions and means to be employed in engraving historical sub jects ; indeed, the graver is equally ne cessary for the completion of imperfec tions in etching, to which must be added the use of the dry point in both, for making the faintest shades in the sky, ar chitecture, drapery, water &c. &c.