YELLOW SUBSULPHATE OF MERCURY'.
491
It is v r ery slightly soluble only in water, requiring 300 times its YYeight ofthis liquid to dissolve it, according to Dumas. It is insoluble in coldalcohol: boiling alcohol abstracts part of its acid.
Characteristics. —Its appearance, its slight solubility in water, andthe action of heat on it. Heated with sulphuric acid the vapour of aceticacid is evolved. The fixed alkalies precipitate the black oxide of mer-cury. Chloride of sodium forms calomel with it.
Composition. —It has the following composition:—
Eq. Eq.Wt. Per Cent. Dumas.
Protoxide of Mercury . . 1 . . . 210 . . . 80*46 . . . 80*60
Acetic Acid.1 . . . 51 . . 19*54 . . . 19*34
Physiological Effects. —It is one of the mild mercurial preparations.From the reports of Guarin, Colombier, and Vogler (Wibmer, Wirk. d.Arzneim. iii. 67) it appears to have acted in some cases with greatviolence, and to have occasioned violent vomiting, purging, abdominalpain, bloody evacuations, &c. These effects probably arose from thepresence of some acetate of the binoxide of mercury.
Uses. — It was introduced into practice in consequence of beingsupposed to be the active ingredient of Keyser’s antivenereal pills. ButRobiquet has subsequently ascertained that Keyser employed the acetateof the binoxide (Dumas, Traite de Chimie,v. 178). It is occasionallyused in syphilitic affections.
Administration. —The dose of it is from one to five grains. Asolution composed of one grain of the acetate dissolved in an ounce ofwater, may be used as a wash. An ointment is prepared by dissolvingtwo or three scruples in an ounce of olive oil.
Hydrar'gyri Subsul'phas Fla'vus.—Yet low Subsul'phate of Mer'cury.
History. — This compound was known to Croll in the sixteenthcentury. It has been termed Twrpeth (or Turbith) mineral (Turpethumminerale), from its resemblance in colour to the root of the IpomceaTurpethum.
Preparation. —It is prepared by adding one part of persulphate ofmercury (the mode of preparing which has been described at p. 464) totwenty parts of warm or boiling water. A supersulphate of mercury isformed in solution, and a subsulphate precipitates.
Properties. —It is a heavy, lemon-yellow, inodorous powder, havingan acrid taste. It requires 2000 parts of water at 60°, or 600 parts at212°, to dissolve it.
Characteristics. — When heated in a tube, sulphurous acid isevolved, and globules of mercury sublimed. Boiled with caustic potashor soda, the red binoxide precipitates, and a solution of sulphate ofpotash is obtained, known to be a sulphate by chloride of barium {vide