ACETATE OF IRON.

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of potassium and the alkalis refuse to act on it in the way they do on the ordi-nary ferruginous salts, until an acid be added. Geiger (Handb. d. Pharm.) re-gards it as a combination of tartrate of iron and ferrate of potash.

Pdrity. —In commerce we frequently meet with an imperfectly prepared Com-pound, in which none or only part of the sesquioxide of iron is in chemical com-bination with bitartrate of potash. In this State it is only partially soluble inwater, and the Solution strikes a blue colour with tlie ferrocyanide of potassium,and throws down a reddish brown precipitate with Solution of potash. The fol-lowing are the characters of the properly prepared salt:—■

Totally soluble in water : the Solution does not change either litmus or turmeric : nor is itrendercd blue by ferrocyanide of potassium ; nor is any thing preeipitated from it by any acidor alkali. The magnet does not act upon it. Ph. Lond.

Entirely soluble in cold water: taste fecbly chalybeate: tbc Solution is not altered by aquapotassa?, and not preeipitated by Solution of ferrocyanide of potassium. Ph. Edinb.

Physiological Effects. —In its effects on the System it agrees, for the mostpart, with other ferruginous Compounds. Its taste, however, is comparativelyslight; its- astringency is much less than the sulphate or sesquichloride, and con-sequently its constipating effects are not so obvious; and its stimulating influenceover the vascular system is said to be somewhat milder. These peculiarities inits Operation are supposed to depend on the tartaric acid and potash with whichit is in combination.

Uses. —It is not frequently employed, yet it is a very eligible preparation ofiron, and may be employed wherever the ferruginous tonics are indicated.

Administration. —The dose of it is from ten grains to half a drachm, in theform of Solution or bolus, combined with some aromatic.

14. FER'RI ACE'TAS, D.—ACETATE OF IRON.

History. —A Solution of iron in acetic acid has long been known and used inthe arts. It constitutes the Iron Liquor of the dyer.

Preparation. —The Dublin College Orders it to be prepared as follows:—

Take of Carbonate [Sesquioxide] of Iron, one part; Acetic Acid, six parts. Digest duringthree days, and filter.

Properties. —It is a deep-red liquid, having an acid chalybeate taste. It rsd-dens litmus.

Characteris/ics. —When heated, it yields acetic acid. Ferrocyanide of potas-sium strikes a blue colour with it; infusion of galls a purplish black.

Composition. —It consists of the Acetate of the Protoxide. and Jlcetate of theSesquioxide of Iron.

The Physiological Effects and Uses are the sattle as other ferruginous Com-pounds.—The dose is from ten to twenty-five drops, in water.

1. FERRI ACETATIS TINCTURA, D. (Acetate of Potash, iwo parts; Sulphate ofIron, one part; Rectified Spirit, twenty-six parts. Rub together the acetate andsulphate, then dry, and add the spirit. Digest for seven days in a well-stopperedbottle; then pour off the clear liquor, and preserve in a vessel perfectly closed.)—*.In this process sulphate of potash and acetate of iron are formed: the latter, aswell as the excess of the acetate of potash, dissolves in the spirit. It is a claret-coloured tineture. It possesses the usual properties of a ferruginous Compound.It is said to be an agreeable chalybeate, and was introduced into the Dublin Phar-macopoeia by Dr. Perceval.—The dose is from half a drachm to a drachm.

2. TINCTÜRA ACETATIS FERRI CUM ALCOHOLE, D. (Sulphate of Iron; Acetate ofPotash, aä3j.;Alcohol,Oij. [wine measure.~] Triturate together tlie sulphateand acetate, then dry them, and when cold add the alcohol. Digest in a well-stoppered bottle for twenty-four hours.)—The dose is from twenty drops to adrachm.