520

Metallic Preparations. — Irox.

fart III.

soda, phosphate of soda, muriate of barytes, nitrate of silver,acetate and superacetate of lead, and almost every salt, thebase of which forms an insoluble compound with sulphuricacid: hence these are incompatible in formula? with thissalt.

Medical properties and uses. — Sulphate of iron is tonic,emmenagogue, and anthelmintic. 1 It is a useful remedy whenexhibited with due caution, in all cases in which preparationsof iron are indicated; but in improper doses it occasions painof the bowels, nausea, and vomiting, and often proves hurtfulby being too long continued. It has been given with advan-tage in diabetes, in the latter stage of phthisis, and in ame-norrhcea, depending on a weakened action of the blood-ves-sels. The dose is from gr. j. to v. combined with ammonia-cum, rhubarb, myrrh, or bitter extracts. It has lately beenused dissolved in water as a lotion to cancerous and phagedeniculcers.*

Officinal preparation. Tinctura Ferri Muriatis. D.

SULPHAS FERRI EXSICCATUS. Edin. Dried Sul-pliate of Iron.

" Take of sulphate of iron, any quantity. Let it beheated in an unglazed earthen vessel, on a moderate fire, untilit become white, and perfectly dry."

Sulphas Ferri exsiccatum. Dub. Dried Sulphate ofIron.

" Take of sulphate of iron any quantity. Let it whiten byexposing it in an unglazed earthen vessel, to a high tem-perature."

In these processes the degree of heat should not exceed212° of Fahrenheit. The salt is merely deprived of its waterof crystallization, without undergoing any chemical change.

Officinal preparation. Oxydum Ferri rubrum. E. D.

OXIDUM FERRI RUBRUM. Edin.3 fad Oxide ofIron.

". Let dried sulphate of iron be exposed to a violent heat,until it is converted into a red-coloured substance."

Oxydum Ferri rubrum. Dub. Red Oxide of Iron.

" Let dried sulphate of iron be roasted in a strong fire un-til it is converted into a red substance; then let this be washedtill the water poured from it does not indicate, by the test oflitmus, the presence of any acid; and lastly, dry it uponbibulous paper."

i It wa3 used as an anthelmintic in the time of Pliny, who says, *' Sumitur ad de-pellenda ventris animalia drac-hmre pondcre cum melle." Not. H'st. Jib. xxxiv. cap. 12.* Edinburgh Med. mid Surg. Journal, it- 3;,!.3 Oxide de ftr rouge (F.) Eissenoxyd (G.) Perossilo rosso di Ferro (/.)