To make this, black silk is strained and brushed over ten or twelve times with the following preparation :—Dissolve halfan ounce of balsam of benzoin in six ounces of rectified spirits of wine; and in a separate vessel dissolve one ounca of isinglass in as little water as may be. Strain each solution, mix them, and let the mixture rest, so that any undissolved parts may subside; when the clear liquid is cold it will form a jelly, which must be warmed before it is applied to the silk. When the silk coated with it is quite dry, it must be finished off with a coat of a solution of four ounces of turpentine in si x: ounces of tincture of benzoin, to prevent its cracking.