By this process the work is distinctly seen during operation; black on a white or silvered ground, without any deceptive glitter, and exactly as it is to be seen in the print. Clean the copper plate, and rub it with a clean rag and a little cyanide of silver. Remove the superfluous cyanide with a clean rag, and the plate will be properly silvered. If the cyanide is too thick, add a little spirits of wine. If it is wished to make the silver of a dead white, slightly roughen the surface of the copper before silvering with fine emery paper, rubbed from right to left, or from left to right, of the way it is intended to work the plate. Use a white ground, made by dissolving white wax in ether - a saturated solution. Let it settle a few days; the clear part only is required, the milky portion at the bottom, being undissolved particles, are probably insoluble and useless. To apply this ground, hold the plate underneath with a pneumatic holder; pour the solution on the silvered side; move the plate gently but firmly from side to side, so that the solution may run to and fro; then pour all the superfluous ground back into the bottle. In finishing, move the plate more rapidly. Let the ground dry for 3 days.

Apply a second coat in the same manner, and let it dry for 4 days in a quiet room, where it will not catch any dust. If the plate is dried by the heat of a spirit lamp, the ground will be transparent, but not of the dead white colour which is desirable. Paint the back and edges of the plate with japan varnish to protect them in the bath, which must be composed as follows: - 20 grammes chlorate of potash, 100 grammes pure hydrochloric acid, 880 grammes water; or the same proportion in English weights. Warm the water, dissolve the chlorate of potash in it, then add the acid. Sketch the subject with some pale but decided water colour, Ted or yellow for example, using the point of a small camel-hair brush. This will remain visible whilst the plate is being etched, which must be done whilst it is in the bath; the acid will, of course, attack the needle, but this action keeps the needles sharp, and they are not costly tools. The bath should be formed in an oblong square piece of light-wood, about 1 1/2 inch thick, and larger than the well, which must be a square hole, a little larger than the plate, and about an inch deep. Cover the board and well with about six coats of japan, which protects the wood from the action of the acid, and the dark colour makes the plate look whiter from the contrast.

A thin piece of wood, stained black, must be used as a hand-rest. Before using a new bath or well, dissolve a small piece each of copper and of zinc in it with acid. Lay the plate in the desired position, and fix it by pressing small pieces of modelling wax at the corners against the plate and the board. Etch with an ordinary strong sewing needle inserted in a holder. It must be sharp enough to scratch well through the silver, otherwise the line will not blacken at once. The wax ground permits the lines to enlarge slowly; thus there is a constant gradation in thickness from the first to the last lines; as the time of exposure diminishes, this property must be carefully attended to. Thus, if the subject requires only about 2 hours' work in etching, this must be spread over 5 hours' exposure in the bath, which is the time necessary to produce the darkest lines; other work can be carried on simultaneously, but this process cannot be hurried. If, however, the subject is elaborate, and requires more etching than can be finished in 5 hours, select for the first sitting various parts over the whole plate; clean and re-ground the plate; at the second sitting add work to that previously done, and so on until the plate is finished, so arranging the times as to work always at the same period of the operation on tones intended to be of the same depth.

This process is acquired with & little practice. If necessary to efface, it may be done in the usual manner, with scraper and charcoal; always re-silver before retouching, if retouching is required. For cleaning the plates, turpentine is usually employed, but shale-oil or petroleum is a better cleanser, and removes the japan varnish very rapidly, whereas turpentine dissolves it slowly.