BRONZING, is the art of imitating bronze, or of communicating to figures in wood, ivory, plaster, &c. that greenish rust which distinguishes the bronze figures of the ancients. The golden bronze is made of the finest and brightest copper dust, and when it is wanted of a red colour, a small quantity of red ochre, well pulverised, is added They are both put on with varnish, and the body to which they are applied is im mediately dried over a chafing dish, to prevent it from turning green.
The following method of bronzing figures is ex tremely simple. After having covered the figure with a coat of gum water, mixed with a little minium, take a little fish glue, dissolved in spirits of wine, by exposing them in a warin place, and add to it some saffron ; then take the filings or dust of any metal which it is wanted to imitate, and apply this, when mixed with the glue, to the figure, with a hair pencil.
In bronzing copper, the Chinese first rub it with vinegar and ashes, till it is well polished. When the copper is well dried in the sun, they cover it with a coat, made in the following manner. Take two parts of verdigris, two parts of cinnabar, five parts of sal ammoniac, two parts of the bill and liver of ducks, five parts of alum ; pound and mix them well, and form them into a clear paste. The copper, after being cover ed with a coat of this paste, is dried, cooled, and washed, and the same operation is repeated about ten times.
Iron may be bronzed merely by rubbing it when hot with the hoof of a cow, and with oil. For farther infor mation on this subject, see a Paper by Alacquer, in the Memoirs of the French Academy for 1767 ; Birch's His tory of the Royal Society, vol. i. p. 103; and Supplement de l'Eneyelopedie, toin. ii. p. 72. (7r)