650

Metallic Preparations. — Silver.

part III.

and incipient chancres. In solution, in the proportion of gr. ij.to f \y of distilled water, it forms a good injection in fistuloussores : and a lotion in an apthous state of the mouth; andin that disease of the gums generally denominated scurvy, inwhich the gum becomes spongy, and its edges hang looselyabout the necks of the teeth. When this latter disease, how-ever, rises to a great height, the sore edges of the gum shouldhe touched with a hair pencil dipped in a much stronger solu-tion, in the proportion of 5J. of the nitrate of silver to f^j. ofdistilled water. ' A solution of one part of the nitrate in 1000parts of water is recommended by Hahnemann 2 as an applic-ation to old sores, and for healing the ulcers of the mouth pro-duced by the use of mercurials.

When given in too large doses, it acts as a poison on thesystem, producing symptoms resembling those induced by theother corrosive poisons. M. Orfila regards common salt asthe antidote of this poison, when given sufficiently early to pre-vent the specific action of the nitrate on the coats of the sto-mach 3 : and so completely is it decomposed by a solution ofcommon salt out of the body, that when a saturated solutionis mixed with a saturated solution of common salt and filtered,the fluid which passes is perfectly inert. When the antidotelias not been administered very early, local and generalbleeding, tepid baths, and emollient fomentations and glystersmust be employed, if any symptom of abdominal inflammationbe perceived.

VRMPARATA EX ARSENICO.

Preparations of Arsenic.

ARSENICI OXYDUJVI SUBLIMATUM, Lond. Pre-pared Oxide of Arsenic.

" Reduce oxide of arsenic to powder; then put it into acrucible, and, applying heat, sublime it into another crucibleinverted over the first."

Syn. Oxide d'arseniquepure {F.~), Weisses Arsenide (G.), Arsenico bianco (/.)•

The greater part of the oxide of arsenic found in the shops,is in the form of semivitreous cakes, which are the product ofa second sublimation of the oxide, after it is obtained fromroasting ores of cobalt. Although prepared on a great scale,yet it is as pure as sublimation can make it, and therefore this

' Fox on the Natural History and Treatment of Diseases of the Teeth.* Annates de Chimie, Hi, 308. ' Traitedes Poisons, $-c. torn. i. p. 49.

2*