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Engraving (Take a ball of etching ground)

Take a ball of etching ground, break it into pieces of convenient size, place them in a bottle, and pour on sulphuric ether. If too thick, add ether; if too thin, take the cork out until it evaporates to proper consistency. To Lay a Solid Ground.

Put a ball of ground into a piece of silk; make a dabber with a circular piece of pasteboard from 2 to 3 in. in diameter, and a pad of wadding on one surface about 1 inch in thickness, tied in a piece of kid-skin or good smooth silk, disposed evenly over this on the under side. Clean the surface of the plate thoroughly with whiting or air-slaked lime; attach in hand-vice; heat the plate until hot enough to boil spittle on the back; rub the ground evenly over the surface required, and use the dabber to distribute it smoothly. If the plate has cooled, heat again to former temperature, then turning the ground downwards, with a lighted candle or taper moved slowly back and forth, as near the surface as may be without touching the ground with the wick, smoke it till sufficiently black. Carefully avoid dust during the whole operation.

To lay Liquid Ground.

Clean the surface of the plate, first with turpentine, then a clean rag and whiting; take an ordinary etching dabber, or make a small ball with raw cotton, cover it with a piece of silk velvet, carefully drawn tight to avoid creases, then dip the dabber in the liquid or pour it on the plate and draw and streak it quickly and evenly; the evaporation of the ether leaves a clear, firm ground.

To Transfer the Outline to the Surface.

Various plans are used. If the design to be copied be the size to engrave, the outline may be traced with a pencil on a piece of oil-paper laid over it. This tracing may be transferred by laying it upon the ground, and while damp passing it through the printing press with a piece of damp printing paper laid over it. It may also be retraced upon the ground by laying between the tracing and plate a piece of thin paper, coated on the under side with vermilion or black-lead, and going carefully over the outline with a blunt point, or lead-pencil.

A better plan is to use gelatine paper. Trace the outline on this article with a sharp point, cutting into it; scrape off the raised edges from the lines with a smooth scraper; then fill the cuts with vermilion or black-lead; carefully wipe off the superfluous dust; lay in proper position, fix down with wax, and, while slightly damp, pass it through the printing press, or with the gelatine dry burnish over the back sufficiently firm to set off the outline, taking care not to break the ground. The best and most recent mode is to get a daguerreotype of the design, the requisite size; cut cleanly and smoothly with a sharp point into the copper over all the outline; this done, remove all the raised edges with the scraper, and get an impression from the copper. While this is still damp place it on the ground and pass it through the press. If the impression has been taken with red ink, the outline will at once appear; if in black, pass a hair-pencil dipped in vermilion lightly over the ground, which must be first freed from damp, so that the vermilion may adhere only to the oil from the impression.

Set it true in a tube, such as are used for handles for parasols; grind off the cutting, and smooth on an oil-stone. The point must be sharpened by rolling it between the palms of the hands, keeping the point on the stone; when once set, it can be easily put in order, by holding it in the right hand, and, while causing it to rotate between the thumb and second finger, draw it smoothly down upon a piece of fine emery paper until the point is perfectly round and sharp, extreme sharpness being undesirable. Hold the point nearly perpendicular between the finger and thumb, draw it without pressure, gently over the emery. The examination of a good specimen of the art will give the best idea of the necessary width, style, etc.

As a general rule, the more distant parts are etched close, and the space between the lines should increase, as the approach is made forward.

Sufficient pressure must be exerted to cut well into the steel, yet not enough to impede an easy motion. Cut with a steady and equal pressure, so that the lines may all present the same color to the eye, as all inequalities show when bitten.

Biting Hard Steel.

The etching completed, carefully cover the unetched surface of the plate with stopping-out varnish, composed of asphaltum dissolved in turpentine, or gum resins, or good sealing-wax, dissolved in alcohol. When dry, form a well around the work, of walling wax, composed of beeswax and burgundy pitch, equal parts dissolved together.

Make a convenient spout by which to pour off the acid. The best acid for biting the steel in ordinary use is the commercial nitric, 1 part; acetic, 3 parts. For delicate tints, such as skies, distances, etc., this mixture may be diluted at pleasure with water to any extent, down to the sharpness of strong vinegar. Steel is acted upon by acid, with great rapidity as compared with copper; it must therefore be quickly put on, and quickly removed, and luke-warm water poured over the surface; blow dry with the bellows; the operation is much facilitated by heating both the plate and acid.

Scrape off small portions of the ground on the lighter parts, to judge thereby of the quality of line, and stop out carefully all that may be considered dark enough. Continue this process until the stronger portions assume sufficient color for the first biting.

Biting Soft Steel.

The use of acids even on hard steel is uncertain and precarious, much more so on soft or partially decarbonized; on such nitric acid being unsatisfactory, resort is had to other materials in search of that success denied to the ordinary means. 1. Corrosive sublimate, 1 oz.; alum, 4 oz.; dissolved in a pint of warm water, bites a fair line. Keep sweeping off the sediment deposited during the process, with a hair-pencil or feather.

2. Spencer's, or magnetic acid; dissolve in oz. of commercial nitric acid and the same quantity of water, and 1 oz. of fine silver. In the like proportions, of acid and water, dissolve 1 oz. of mercury. Then mix solution of silver and of mercury, each, 1 part; water, 25 parts; solution of nitric acid, part,

This mixture bites very rapidly when once started; it will, however, lie perfectly inactive until some one of the following plans is used. 1. Heat a steel point by rapid friction or fire, and with it touch the steel through the acid and ground; a black deposit at once forms; sweep it off with a feather. 2. With a strip of zinc polished at both Fix down with wax, strips of wood or leather ends, touch with one end the acid, and with the about in. thick upon the margin. The best and other, a clear piece of steel. 3. Wet a part of the most useful point, is a good stub small round file. | surface of the plate with spittle; this is a verv Etching. ready means. 4. Dip a point in corrosive subli- theory framed; the result of experiment proved it mate; this pressed into the steel will force action; to have been well founded, and mezzo-tinto, a comor, 5. Put corrosive sublimate on for a moment, pour rapidly off, and as quickly put on the magnetic acid. To Set and Use the Graver.

Lay the sides, the angles of which form the belly, on the oil-stone; rub gently, taking care to keep the part flat upon the stone, until the edge is sufficiently sharp; then, with the handle of the graver in the hollow of the hand, and the forefinger on the belly, hold it at an angle of about 30 degrees, and rub the end till a good point is obtained. In cutting, hold the handle of the graver in the hollow of the hand, and the graver, between the forefinger and thumb, the plate lying solid upon the table, turning it as occasion may require. The outlines of figures are usually dotted in with the etching, slightly bitten, and stopped out, and the serious part of figure engraving now commences, by laying in the lines, according to the taste and skill of the workman, lightly at first, and gradually cutting deeper and broader into the darker parts. Sand-bags and oil-rubbers are exploded institutions. Aquatint Engraving.

Etch the outline; bite slightly in the distance and light parts; more strongly those near at home.

Clean the plate well to lay the ground, which is thus done: dissolve resin in proof alcohol; for distance, less resin is required. Increase the quantity for the nearest parts. Pour this mixture over the plate, run off the superfluous matter, and in drying it will form a granulation on the surface.

This granulation is fine or coarse in proportion to the quantity, more or less, of resin contained in the alcohol. When the resin is in excess no granulation will form. Stop out, bite, and re-bite, as in etching.