Caustic, Mercu′′rial

Syn. Caustic of nitrate of mercury ; Causticum ac′idi hydrar′′gyri nitra′tis , C. h. deutronitratis , L. From mercury, 1 part; commercial nitric acid, 2 parts; di olve. 2. (Cutan. Hosp.) Mercury, 1 part; nitric acid (sp. gr. 1·5), 2 parts. 3. (P. C.) As No. 1, but evaporating the solution to 3 ⁄ 4 ths its weight. These liquids are applied with a pencil or lint, in scrofulous and syphilitic ulcers and eruptions, and in lupus, psoriasis, lepra, and other obstinate skin diseases; but their use requires great care. 4. (With arsenic.—Cutan. Hosp.) Mercury, 1 ⁄ 2 oz.; nitric acid, 1 ⁄ 2 oz.; arsenious acid, 1 ⁄ 2 dr.; as before.