CUP

3*1

mb-borate of soda ; acetate of ammonia ; tartrate of potass • murtofe oflime ; nitrate of silver; subacetale, and acetate of lead; oxy-muriate ofmercury; all astringent vegetable infusions and tinctures. Iron immersedin the solution, precipitates copper in it metallic form ; hence the exhi-bition of the filings of iron has been proposed as an antidote.* Medici-nal Uses. It is emetic from grs. ij to xv tonic gr i ; it is. however,but rarely u=ed internally except as an emetic ; externally it is employ-ed as an escharotic ; and. in solution, as a stimulant to foul obstinate ul-cers t In the proportion of half a drachm to eight ounces of rose water,

* It may be here observed that Copper, in its metallic form, exerts no action on thesystem. A most striking instance of this fact occurred during my hospital practice,in the case of a young woman who swallowed six copper penny pieces with a viewof destroying herself; she was attended bj Dr. Maton and myself in the WestminsterHospital for two years, for a disease which we considered visceral, but which wagevidently the effect of mechanical obstruction, occasioned by the coin. Aiter a lapseof five years she voided them, and then confessed the cause of her protracted disease,during the whole course of which no symptom arose which could in any way be at-tributed to the poisonous influence of copper. Dr. Baillie, in his morbid anatomy,relates a case, In which five halfpence had been lodged in a pouch in the stomach, fora considerable time, without occasioning any irritation ; and Theodore Gardelle, af-ter his conviction for the murder of Mrs. King, in Leicester Square, swallowed anumber of halfpence, for the purpose of destroying himself, but without any ill effects.Mr. A. T. Thomson relates also two cases of halfpence being swallowed by children,in one of whi»h the copper coin remained six months in the intestines, and in theother two months. The filings of copper were formerly a favourite remedy in rheu-matism, a drachm of which has been taken with impunity for a dose. It appearstherefore that metallic copper does not undergo any change in the digestive organ,by which it is converted into a poison, notwithstanding the presence of substances,which, out of the body, would at once render it destructive, as we have too manycases to show, from the careless u=e of copper utensils in cookery. It is, however, avery important fact, that copper cannot be dissolved while tin is co-existent in themixture, hence the great use of tinning copper utensils: and farther, it is assertedthat uutin'ied coppers are less liable to be injurious when pewter spoons are used ferstirring, than when silver ones are employed for that purpose : the explanation ofthis fact is to be sought for in the well known principle of Electro-Chemistry, and■which has lately been applied with so much ingenuity by the illustrious President ofthe Royal Society, for the protection of copper on the bottom of ships, by the juxta-position of small discs of Tin or iron.^: For the same reason, M. Proust has shewnthat the tinning of kitchen utensils, which consists of equal parts of tin and lead, can-not be dangerous from the presence of the latter metal, since it is sufficient that thelead should be combined with tin, in order to prevent it from being dissolved in anyvegetable acid. VI. Guersent therefore is wrong when, speaking of the tinning ofcopper vessels, he says, " it is a light veil, which conceals the danger, instead of beinga true preservative, and that it only inspires a security often fatal." Some recentexperiments, however, of Dr. Bostock, have shewn, that, in consequence of the vola-tility of acetic acid, copper is not protected by the juxta-position of discs of tin;since the acid under such circumstances ceases to form a part of the galvanic circle.The poisonous effects of the salts of Copper have been strikingly illustrated duringthe oro-ecution of Sir H. Davy's experiments above alluded to, for it is found thatwhen the copper sheathing of ships is not protected by the contact of another metal,they are uniformly free from nanne animals, but that where the solution of the cop-per is prevented by galvanic action, the bottoms soon become covered with everyspecies of sea insect.

t Bates's Aao\ Camphorata. —Sulphate of Copper is the base of this prepara-tion, which was strongly recommended by Mr. Ware The following was his recipe ;R. Cupri Sulph. Boli Gallic, a. a. gr. xv. Camphorae gr. iv. solve, in aq. fervent, fjiv, dilueque cum aqua; frigidas oiv ut fiat Collyrium.

f; For a further explanation of this curious fact the student may consult my work onMedical Chemistry