Mercurous Phosphate, Syn. Hydrargyri phosphas, L. Prep. Add a solution of mercurous nitrate (slightly acidulated with nitric acid) to a solution of sodium phosphate, and wash and dry the precipitate which forms. In its physical characters it closely resembles calomel, than which it is said to be more appropriate in certain cases, especially in secondary syphilis. Alkalies turn it black.—Dose, 1⁄4 to 1 gr., made into a pill with sugar and aromatics.
Mercurous Sulphate. Hg2SO4. Syn. Subsulphate of mercury, Sulphate of the suboxide of m., Protosulphate of m.†; Hydrargyri subsulphas, L. Prep. By adding sulphuric acid to a solution of mercurous nitrate. The salt falls as a white crystalline powder.
Mercurous Sulphide. Hg2S. Syn. Subsulphate of mercury; Hydrargyri subsulphuretum cum sulphure, H. s. nigrum, L. Prep. 1. (Pure.) This falls as a black precipitate when a solution of mercurous nitrate is treated with sulphuretted hydrogen or ammonium sulphide.
2. (Impure; Ethiops mineral; Hydrargyri sulphuretum cum sulphure, H. s. nigrum—Ph. L. 1824 & Ph. D. 1826); (Æthiops mineralis—Ph. L. 1836 & Ph. D. 1826.) (Quicksilver and sulphur, equal parts, triturated together in a stoneware mortar—Ph. D.) until globules are no longer visible.
Prop., &c. The last preparation of mercurous sulphide is alone employed medicinally. It is a heavy, insoluble, black powder. It is frequently met with imperfectly prepared, and sometimes adulterated. It is said to be a mixture of mercurous sulphide and sulphur, in variable proportions depending on the length of the trituration. On the large scale it is generally made by melting the ingredients together, and afterwards reducing the mass to a fine powder in a mill or mortar. It is said to be vermifuge and alterative, and has been used in some cutaneous and glandular diseases, but appears to be nearly inert.—Dose, 5 to 30 gr.
Mercurous Tartrate. (P. Cod.) Syn. Proto-tartrate
of mercury, Hydrargyri tartras. Made by adding a solution of proto-nitrate of mercury in water, slightly acidulated with nitric acid, to a solution of tartrate of potash as long as a precipitate forms. Wash it with distilled water, dry it in the shade, and keep it in bottles covered with black paper.—Dose, 1 to 2 gr.
MERCURY, Other Preparations of.
Mercury, Hahnemann’s. Syn. Hahnemann’s soluble mercury, H.’s black oxide of m., Black precipitate of m.; Hydrargyri præcipitatum nigrum, Mercurius solubilis Hahnemanni, L.—a. By dropping weak ammonia into a solution of mercurous nitrate as long as the precipitate formed is of a black colour; the powder is washed, dried in the shade without artificial heat, and then preserved from the light and air.
(Ph. Bor. 1847.) Solution of mercurous nitrate (recent; sp. gr. 1·1), 91⁄4 oz.; distilled water, 2 lbs.; mix, filter, and add to the solution of ammonia (sp. gr. ·960), 1⁄2 oz., diluted with water, 4 fl. oz.; collect the powder immediately on a filter, wash it with water, 3 fl. oz., and dry it, &c., as before. A very black powder.—Dose, 1⁄4 to 1 gr.