FERRUM.— IRON.

four hours, triturate the mass with coldwater, pour off the turbid liquor, set itaside, place the deposit upon a filter, andwhen it has lost the greater part of its humi-dity, put it into a narrow and deep earthenvessel, and dry it with a gentle heat. (Swe-diaur ; Van Mons)

After i he process of Guibourt.R. Iron Filings, any quantity.

Triturate them in a mortar, then putthem into a large earthen pan, and washthem till the water comes off perfectly in-sipid : then press the filings, incline the panto let the water drip from them, and re-turn the pan to its horizontal position.Stir frequently the filings with an iron spa-tula, moistening them with water from timeto time so as to keep up always the samedegree of humidity. At the expiration offour or five days, wash the mass, filter theturbid water, express the separated oxide,and dry it quickly in a stove. (Gall.;Form. Hop. Fr.)

The product of this process does not differfrom that of the preceding.R. Red Oxide of Iron, any quantity.

Olive Oil, a sufficient quantity,

to moisten slightly the oxide. Distil to dry-ness in a glass retort, with a gradually aug-mented heat. Triturate the residue whencold, and preserve it. (Fenn. ; Genev. ;Hann. ; Olden; Pol.; Borus. ; Sax.;Brugnatelli ; Van Mons)

This process approaches that which Savehas proposed for obtaining aethiops fromthe beaten scales of iron.R. Iron Filings, any quantity.

Heat them to redness in a crucible, andsprinkle them occasionally with a little wa-ter, waiting each time till it becomes de-composed or evaporated and the metal red-dens again. Continue to proceed thus tillthe mass becomes black and opaque : finally,triturate this while hot, and preserve thepowder after having sifted it. (Batav. ;Belg. ; Van Mons)

Brugnatelli proposes a similar pro-cess, which consists in throwing pieces ofred hoi iron into pure water, collecting thescales which are deposited at the bottom ofthe vessel, purifying them by means of amagnet, and finally levigating them.

Gay-Lussac, to determine the compo-sition of the deutoxide of iron, obtained itby exposing fine iron wire to the vapour ofwater, in a porcelain tube heated to red-ness, till it ceased to disengage hydrogen .R. Sulphate of Iron, any quantity.

Dissolve it in distilled water, and addsubcarbonate of potass or of soda to thesolution, till no more precipitate is formed.Filter the liquor, and dry the precipitate ;

641

one parttwo parts.

form this into a paste with linseed oil, andcalcine the mass slowly till the oil becomesconsumed. Preserve the residuum. (Austr. ;Bavar. ; Ross.)

R. Sulphate of Iron, any quantity.

Dissolve it in distilled water, and add so-lution of sub-carbonate of soda to the liquortill no more precipitate is formed; dry thisslowly, and add to it diluted acetic acid inthe proportion of three to eight. Distil themixture with a strong heat in a reverberatoryfurnace, and preserve the oxide which re-mains in the retort. (Gall. ; Brug-natelli)

This process, like the fourth and thesixth, give for a product an oxide mixedwith carbon.

R. Red Oxide of Iron, in powder,

any quantity.Put it into a narrow and deep earthenvessel, and burn alcohol upon it till it isconverted into black oxide. Boil it for aninstant in water, pour off the liquid, anddry the powder with a moderate heat.(Brugnatelli)

After the process of Vauouelin.R. Red Oxide of Iron,Iron Filings,

Mix, and calcine for an hour in a coveredcrucible ; withdraw the mass when cold,and reduce it to powder. (Ferr. ; Fee ;

Swediaur)

This process, followed on a large scale,would not perhaps always give a homoge-neous product.

Bucholz recommended seventy-two partsof red oxide, and twenty of filings.

Thenard says that in some laboratoriesthe black oxide of iron is obtained bymaking a paste with iron filings and water,and sprinkling it with the sixteenth of itsweight of nitric acid (36 degrees). Wethink this method belongs to Ingenhousz.Thenarix observes that the preparation ofthis oxide might be dispensed with, as it isso abundant in nature, and so frequently ina pure state. It is certainly remarkablethat so many processes should have beeninvented for the preparation of a medica-ment which is really of very little importance.

The black oxide does not seem to bemuch superior to the filings, which also arenot much employed. — Dose, from ten tofifteen grains.

cachectic powder.

Pulvis aromatico-ferratus. (Swediaur ;Van Mons)

R. Black Oxide of Iron, four parts,

4 M