Proceed as for the last, omitting the brown after the black.
BLUE.
After giving four or five coats of the chemical blue diluted with water, wash lightly with weakened aqua regia, which will take off the green reflection produced by the yellow tint of the leather.
GREEN.
Give three or four coats of the green liquid, extended in water according to the shade required. Any of the other colours noticed in the preparations may be thus executed.
OLIVE.
After giving a slate-colour, apply yellow, boiled with a small portion of blue, on the cover, rubbing it equally in while hot, to insure uniformity.
PEARL GRAY.
This colour must be executed carefully, so as to be perfectly uniform and without stains. Colour over with exceedingly weak black liquid, till a pale gray is produced. The weaker it is, the better will the workman succeed. Then pass over a light coat of fine red mixed in a large portion of water, so as to give a light red reflection scarcely distinguishable.
SLATE.