On this tint the oil-rubber should be very carefully used. The plate being quite clean, and placed under the shade, it will be found that the tints or bitings are rather sharper against each other than is required. The burnisher will remove this by rubbing the parts which are to be reduced in colour. The parts to be burnished should be slightly touched with the oil-rubber. The use of the burnisher requires some skill, which can only be acquired by practice. The scraper is useful for bringing out sharp lights, and modulating the darker parts. If the first ground is not satisfactory, the plate must be polished, and another ground laid. The second ground must contain more rosin than the first; bordering, biting, . and stopping-out, as before. The plate should be sent for proof before the second ground is laid. The proof will show where increase and where reduction of colour is required. The burnisher will reduce; the increase can only be had by laying another ground.

Ground To Etch On

Mix a small quantity of turpentine varnish with turpentine slightly coloured with black, but only sufficiently so as to render the lines made by the needle perceptible. With this thin varnish, and a good-sized camel-hair brush, go over the plate lengthways; when that is set, repeat the coating crossways; let it set, and lay it by for a night if convenient. The etching finished, border and bite as before directed, but with stronger acid.

General Instructions

Great care must be taken while laying the ground that there is not much dust floating in the air; for, should the slightest particle of flock lodge on the plate whilst wet it will cause what is called an accident. Wherever the speck falls the rosin will corrode around it, forming a . white spot on the ground where the acid has been applied. These accidents are of little consequence, unless they should happen on the sky. To do away with these light places, the chalk tool, or dotter, must be used this is simply a bent graver. From pouring the ground mixture backwards and forwards, it is likely to become foul; it should then be passed through a double piece of clean muslin, and put away in a bottle to settle. The burnisher acts as principal in forming a good sky and background. As the action of the acid will leave all the tints with a sharp edge, they must be softened down with the burnisher. Every fresh aqua-tiuta ground laid should be increased in the size of the grain, or the ground will become murky.

To enrich and darken the foreground and foliage, etching over the parts with the etching ground above described is much the easiest method.

Rosin-Ground Engraving

This is well adapted to ornamental work, as great depth of colour can be obtained. The process is extremely simple. The best white rosin should be reduced to powder by pestle and mortar, then placed in fine double flannel, and tied up in a bag. The plate must be heated as in laying etching ground, and the rosin then powdered on the surface; lay the plate on a table, so as to leave both hands free, lake the bag of rosin in the right hand, and strike it against the left. The bag must be held some distance from the plate, which will force the powdered rosin to escape from the flannel bag, and, falling on the hot plate, will there fix itself in small spots, something similar to the aqua-tint deposit, but much more enduring. This produces very imperfect results, and causes dry-ground engravings to be looked on with disfavour. The stopping-out process is the same as in the aqua-tint. By repeating the process with the flannel bag, a positive black ground may be procured, as dark and more enduring than a mezzo-tinto ground, and it may be scraped on much in the same way.