2. (B. P.) Prep. Sulphate of iron, 9 oz.; arseniate of soda dried at 300° F., 4 oz.; acetate of soda, 3 oz. Dissolve the arseniate and the acetate of soda in 2 pints, and the sulphate of iron in 3 pints, of boiling distilled water, mix the two solutions, collect the white precipitate which forms on a calico filter, and wash until the washings cease to be affected by a dilute solution of chloride of barium. Squeeze the washed precipitate between folds of strong linen in a screw-press, and dry it on porous bricks in a warm air-chamber whose temperature shall not exceed 100° F.—Dose, 1⁄16th of a gr.
Ferrous Arsenite. Fe(AsO2)2. Syn. Ferri arsenis, L. From the potassium arsenite, and ferrous sulphate, as the last. A yellowish-brown powder, occasionally used in medicine as a tonic, alterative, and febrifuge.—Dose, 1⁄16 to 1⁄12 gr.
Ferrous Bromide. FeBr2. Syn. Ferri bromidum, L. Prep. (Moir.) Bromine and iron filings, of each 1 part; water, 3 parts; mix in a stoppered phial, set it aside, occasionally shaking it, for 2 or 3 days, and when the colour of the bromine has disappeared, and the liquid becomes greenish, filter and evaporate to dryness.—Dose, 1 to 6 gr., as a tonic, diuretic, and resolvent, in similar cases to those in which iodide of iron is given.
Ferrous Carbonate. Fe(CO3). Syn. Protocarbonate of iron; Ferri carbonas, F. subcarbonas, L. This occurs in nature as SPATHOSE ORE, the chief constituent as of CLAY IRONSTONE, and in many CHALYBEATE WATERS.
Prep. (B. P.) Ferrous sulphate (sulphate of iron), 2; ammonium carbonate, 11⁄4; boiling distilled water, 320; refined sugar, 1. Dissolve the sulphate and ammonium carbonate each in 1⁄4 of the water, and mix; allow to stand for 24 hours and decant, of the clear solution, add the remainder of the water to the precipitate, stir well, allow to settle, and decant off. Collect the deposit in a calico filter, press, rub in the sugar in a
porcelain mortar, and dry at a temperature not exceeding 212° Fahr. Small coherent grey lumps. Precipitate a solution of ferrous sulphate with a solution of sodium carbonate, well wash the green powder with water which has been boiled, and dry it out of contact with the air. On the slightest exposure to air it is converted into ferrous hydrate or oxide. This change is for the most part prevented by combining it with sugar, as in the following preparation.
With sugar: Ferri carbonas saccharata, B. P.; SACCHARINE C. OF I.; FERRUM CARBONICUM SACCHARATUM, FERRI CARBONAS CUM SACCHARO—Ph. L., FERRI CARBONAS SACCHARATUM—Ph. E. & D. L.—(Ph. L.) Ferrous sulphate, 4 oz.; sodium carbonate, 41⁄4 oz.; dissolve each separately in quart of boiling water, and mix the solutions whilst hot; after a time collect the precipitate, wash it frequently with water, and add of sugar, 2 oz., previously dissolved in water, 2 fl. oz.; lastly, evaporate the mixture over a water bath to dryness, and keep it in a well-closed bottle.
Prop., &c. A sweet-tasted greenish mass or powder, consisting chiefly of carbonate of iron. It is one of the best of the chalybeates.—Dose, 5 to 10 gr. When pure, it should be easily soluble in hydrochloric acid with brisk effervescence.
Ferrous Chloride. FeCl2. Syn. Protochloride of iron; Muriate of iron; Ferri chloridum, L. Prep. 1. (Anhydrous.) By passing dry hydrochloric acid gas over ignited metallic iron. The chloride sublimes in yellowish crystals.
2. (Hydrated.) Dissolve iron filings or scale in hydrochloric acid, evaporate and crystallise. Soluble green crystals.