cum and Mercury Plaster, B.P.; Ammoniac Plaster with Mercury, U.S.P.

Preparation. - B.P. By rubbing mercury 3 oz. with warm olive-oil 1 fl. dr., and sulphur 8 grs. until the globules of mercury are no longer visible, then adding melted ammoniacum 12 oz. and mixing. U.S.P. Mercury 180 is extinguished with sulphur 1 and olive oil 8 as in the B.P. process. Ammoniacum 720 is digested with diluted acetic acid 1,000, strained, evaporated until it hardens on cooling. It is then added while hot to the mercury, and mixed. Then enough lead plaster previously melted is added to make up to 1,000 parts.

Both plasters are used to promote the absorption of glandular enlargements, buboes, nodes, and are applied over the liver in chronic enlargement and induration. Emplastrum hydrargyri is useful also in sycosis, lupus, and other deep-seated infiltrations of the skin.