Silver leaf and tin-fe:t are made to represent gold, by covering them with a varnish or tacker of white resin, gum-sandarac, aloes, and red lead, mixed up and boiled with linseed oil. See Gilding on leather.
False Gilding upon Leather. This is an art which was formerly practised very extensively for the hangings of apartments. At present it is scarcely known, but some very fine specimens which remain perfect, after being in use for a century, spew that it is a most durable kind of furniture for rich apartments. In the French Collections des 4rts et des :Vetiers, the following account of this art is given. " The leather of calf skin is preferable to any other; the skins are softened in water, then beaten on a stone, and curried out to their greatest extent whilst wet ; when dry they are cut square, and all reduced to the same size; after which, if any skins are defective, they are pieced with the fragments, which are joined by glue ; the edges of the joints being pared away so as to make no increase of thickness. The grain side of the leather is now rubbed over with a piece of size, whilst in a state of jelly ; and before this size dries, leaves of silver are laid on, in the manner before described of the gold leaves for burnished gilding. When covered with silver, the skins are dried till they are in a proper state for burnishing, which is done by a large flint fixed in the middle of a wooden handle : the workman holds it with both hands, and forcibly rubs upon the silver till it becomes brilliantly burnished. The appearance of gold is now given to the silvered surface, by covering it with a yellow varnish or tacker, which is composed of white resin four pounds and a half, common resin the same quantity, gum sandarac two pounds and a half, and aloes two pounds. These ingredients are melted together in an earthern vessel, and after being well mixed by stir ring, seven pints of linseed oil are poured in, and when the composition is sufficiently boiled to make a perfect union, and to have the consistence of syrup, half an ounce of red lead is added, and the liquor is passed through a flannel bag.
To apply this varnish, the silvered skins are spread out upon a board, and fastened down by nails : These are ex posed in the sun, and when thus warmed, the white of an egg is spread over the silver. After this is dry, the work man lays on the varnish, by spreading it with his hands till he covers the whole. The varnish will dry in the sun in a few hours, and is very durable. When the gold is desired to be laid according to any design, the varnish is printed upon the surface of the skin by a wooden block and a roll ing press. By this means only the printed parts will ap pear to be gilt, the others remaining in silver as a ground, and are frequently painted in oil colours.
False gilding for picture frames and other similar orna ments, may be performed with silver laid on in the manner described for burnished gilding, and the above varnish laid on after it is burnished : as the varnish preserves it, tin foil answers almost as well, except that it will not bear too fine a burnish.
False Gold Powder is made by melting tin, and pouring into it about half as much mercury. The amalgam thus produced must be pounded and mixed up with sal ammo niac and sulphur, each in weight about half the tin. The composition being calcined in a matrass, will form a bright gold coloured powder, which answers very well for japan ners, but will nut keep its colour unless it is covered by a varnish. For farther relative to this art, see Handmaid to the arts ; Lewis's Commercium Philosophic° Technicum; and the Circle Mechanical Arts. (J. F.)