Place a small quantity of gunpowder in a silver spoon; pour over it some of the spirit; light the spirit, and let it burn to the powder. If the powder takes fire and explodes, the spirit is good, and fit for use. Should it remain in the bottom of the spoon, black and wet, the spirit has been adulterated with water, and is not fit for the purpose.

Trial Of Aqua-Tinta Ground

Have a tin trough about 2 in. wide, and rather longer than the plate, with a convenient spout at one end; the trough is to act as a receiver of the spirit when poured over the plate; the spout to return it to the bottle.

Laying The Ground

Polish the plate well, as before directed. Place it at a slight slope, the tin trough under the lower edge to receive the spare mixture. As a trial of the ground, pour the liquid from each bottle, and make a small patch in different places at the bottom of the plate. When the liquid has run off into the tin trough, lay the plate fiat, and with a piece of rag wipe the lower edge. Take a magnifying glass, and look at the grains deposited on the copper. Having poured the spirit from the trough to bottle No. 1, make choice of the grain most likely to suit the work; if neither of the three should, mix the large grain and the small together until it does, letting the mixture settle well before it is used. Remove the trial spots; polish the plate well, and place it as directed for trial with the side intended for the foreground next to the tin trough. Pour the mixture along the top of the plate, from one end to the other, until the whole of the surface is covered. As soon as the spirit has run into the tin, lay the plate fiat; the sooner it is laid fiat the rounder will be the setting of the grain; the longer the plate remains on the slope the more elongated the deposit of rosin will become, which for some sort of work will answer better than round: such as broken rock, waterfalls.

In most cases it is advisable to make a very fine etching of the subject intended to be placed on the plate prior to laying the aqua-tinta ground; in the end it will save time. The etching must be very light, otherwise the aqua-tinta ground will hang round the . lines, and form a ray of light. Should the. etching be strong, it will require to be filled up with wax, and polished off before laying the ground. Engravers send the plate to the printer's to have it filled up with ink, which is the best method. If obliged to use wax, heat the plate rather above what is required for the etching ground; the surface is then wiped off, and polished with the soft part of the hand slightly rubbed with whiting.

Stopping-Out The Lights

Place on the left side a small looking-glass in a leaning-forward position; lay before It the drawing intended to be worked from, with the base or foreground towards the bottom of the glass; you will then see the subject reversed in the glass. Go over the margin as directed in the head Etching. For this a camel-hair pencil and the same pot of varnish, with a little more lampblack added, and well worked together, should be used. Stop out all the white lights seen in the drawing. By the time this is done, the varnish on the margin will be dry or set; if not, the plate must remain until it is. Go over the margin again with the same varnish, and let that set hard. Place your border wax as before directed, making the spout rather larger, that you may be enabled to pour off the acid quickly if necessary. Use the same aquafortis as for etching, but the strength somewhat increased, as it must remain on the plate a much shorter time. Lay the plate an inch or so over the front of the table, with a piece of canvas underneath, having small wedges of wood ready to be used should the acid not float evenly.

First Lights

Pour on the acid rather quickly, running it from the bottle to the jug, then on to the plate; another jug, having been filled with cold water, should be kept ready for washing off. When the acid has entirely covered the plate, the surface should immediately assume a frosty appearance, but not come up in bladders. Little more than a minute may be enough for the acid to remain on the plate; pour it into the jug as quickly as you can without spilling it; immediately wash off with cold water; have a receiver for the wash-water, as it must be thrown away.

Second Lights

Dry the surface of the plate, and, should any spots of moisture remain on the surface, carefully take them up with blotting paper. Now, with the same varnish, stop out all the second lights. To prevent injury to the border, place two blocks or old books under the ends of your rest.

Third Lights

When the second stopping-out is set, put the plate through the same process with the same acid. Again dry the plate, and stop out the third light parts; when set, apply the acid, but let it remain on rather longer; wash as before directed. As all the flat tints are now laid, it only requires the very dark ones. Ascertain, with a magnifying glass, if the spots of rosin remain on the plate; if so, it will bear biting again. Should the ground remain sound enough to stand another application of the nitric acid, you must prepare a mixture called touching stuff.

Touching Stuff

Burn a good-sized cork to ashes; take some treacle and add as much ivory black as will make the mixture a dark colour by the addition of a small quantity of sheep or ox-gall; it works almost as free as the varnish. Make the composition into a ball, a small quantity to be used with water when required. Again lay the plate for work. Paint over all parts that are required to be very dark, such as projecting foliage, and all sharp shadows, with the touching stuff, loading all the touches with as much of the mixture as can be placed on them. When the touching stuff is dry, mix some turpentine varnish, slightly coloured with lampblack, and with a larger brush go over the whole of the plate. When this last, varnish is set, pour on some very weak acid and water; the former washings of the plate will do. With the soft camel-hair pencil used for the acid, work up the touching stuff until the whole cornea off;, then wash the plate clean with cold water, and again apply the acid. For this last biting the acid may remain on the plate as long as the ground will stand. This may be ascertained by clearing the plate with the camel-hair pencil, and using the magnifying glass. The plate must now be cleaned, and remove the border wax as before described.