the art or manner of making anything white. See BLEACHING.

**BLANCHING of Iron Plates**, is performed with aquafortis and tin.

**BLANCHING of Woollen Stuffs**, is done with soap, chalk, or sulphur. See BLEACHING Index.

**BLANCHING of Silk**, is performed with soap and brimstone.

**BLANCHING of Wax**, is by exposing it to the sun and dew. See BLEACHING Index.

in coinage, the operation performed on the planchets, or pieces of silver, to give them the requisite lustre and brightness. They also blanch pieces of plate, when they would have them continue white, or have only some parts of them burnished.—Blanching, as is now practised, is performed by heating the pieces on a kind of peel with a wood fire, in the manner of a reverberatory; so that the flame passes over the peel. The pieces being sufficiently heated and cooled again, are put successively to boil in two pans, which are of copper: in these they put water, common salt, and tartar of Montpelier. When they have been well drained of this water in a copper sieve, they throw sand and fresh water over them; and when dry, they are well rubbed with towels.

among gardeners, an operation whereby certain salads, roots, &c., are rendered whiter than they would otherwise be.—It is thus: After pruning off the tops and roots of the plants to be blanched, they plant them in trenches about ten inches wide, and as many deep, more or less as is judged necessary; as they grow up, care is taken to cover them with earth, within four or five inches of their tops: this is repeated from time to time, for five or six weeks; in which time they will be fit for use, and of a whitish colour where covered by the earth.

**BLANCHING** also denotes the operation of covering iron plates with a thin coat or crust of tin. See LATEN.