Break grossly the bones of sheep's trotters, and boil them in water till cleared from their grease; then put them in a crucible and calcine -afterwards reduce them to a powder in a mortar. To some thin paste add an equal quantity of the bone powder, and grind the whole mass well together. This mixture forms the ground for the pannel. When the pannel has been well pumiced, some of the ground is to be rubbed on with a pumice stone, that it may be incorporated with the pannel. Another coat of the composition is next applied with a brush, when it is suffered to dry, the surface being afterwards rubbed over with sand-paper. A thin coat of composition is then applied with a brush, and if a coloured ground be required, a coat or two must be added, so as to complete the absorbent ground. When a pannel thus prepared is wanted to be painted on, it must be rubbed over with a coat of raw linseed or poppy oil, as drying oil will destroy the absorbent quality of the ground, and the artist's colours should also be ground very fine. The grounds thus prepared do not crack; they may be painted in a very short time after being laid, and, from their absorbent quality, allow the business to be proceeded in with facility and better effect than with those prepared in the usual way.', ,The only ground which we shall mention the construction, is one for which the Society of Arts gave their honourary silver medal, and a premium of fifty guineas, to Mr. S. Grandi; it is called the Venetian ground, and has met with much approbation from many eminent artists.,