8. The end on which the engraver is to exert his skill, is planed and scraped, to render the surface smooth, and the block having been cut to the proper size, the drawing is made upon it in India ink, or with a lead-pencil. The block is now ready for the artist who, in executing the work, holds it with one hand, on a cushion made of sand and leather, while, with the other, he cuts away the superfluous wood. The part intended to make the impression in printing, is left standing. 9. Wood engravings, well executed, are scarcely inferior to those of copper and steel, and, for many purposes, they are preferred. They are remarkably convenient, since they can be inserted into a page of types, where illustrations or embellishments may be required, and be printed without separate expense. They will also bear a great number of impressions--generally 100,000. In this respect, they are decidedly superior to metallic plates. They can likewise be multiplied indefinitely by the process of stereotyping. THE COPPERPLATE ENGRAVER. 1. The engravers on metallic surfaces are termed copperplate engravers, not because copper is the only metal on which they exert their skill, but because it is the one on which they usually operate. The plates are prepared for the artist by the coppersmith, by rubbing them with brickdust and charcoal, after having cut them of a proper size from sheets of copper. 2. The instruments employed by this artist are few and simple, the principal of which are, the _graver_, the _dry-point_, the _scraper_, and the _burnisher_. The _graver_ is a small bar of steel, of a square or lozenge form, and, with the short handle into which it is inserted, about five inches in length. One of the angles of the bar is always on the under side of the instrument, and the point is formed by bevelling the end from the upper side, or angle. The square form is used for broad strokes, and the lozenge for fine ones. 3. The _dry-point_, or needle, is a steel wire with a long cylindrical handle; or it is simply a wire of sufficient length and size to be used without a handle. The _scraper_ has nearly the form of a triangular pyramid; and the cutting part, which has three edges, is two or three inches long. The _burnisher_ has a form nearly conical, and, without the handle, is about three inches long. The last two instruments are frequently made of the same piece of steel, properly forged at each end. In such case, the middle part of the steel is the handle by which they are held. 4. Of engraving on copper, the following are the principal varieties or styles: 1. Line engraving; 2. Stippling; 3. Etching; 4. Mezzotinto; 5. Aquatinta. For the purpose of conveying some idea of these different branches, we will describe them under distinct heads.