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of salt and salted provisions, and to be prevented or cured by vegetableacids (especially the citric) and fresh provisions. It appears, therefore,in the highest degree probable, that scurvy, and the effects caused by thelong-continued employment of the alkalies, are analogous conditions ofsystem.
Uses. —Caus.ic potash is employed for various purposes in medicine,the principal of which are the following:—
(a.) As an escharotic. —Potassa fusa is sometimes used as a caustic,though its employment is not free from objection; for its great deli-quescence occasions some difficulty in localizing its action. It may beemployed for the production of an issue, but we must proceed thus:—Apply to the part one or two layers of adhesive plaster, in the middle ofwhich is an aperture of the exact size of the intended issue. Thenmoisten the potassa fusa, or the potassa cum calce, and rub on the partuntil discoloration is observed. Wash, and apply a linseed-meal poul->tice; and when the eschar is detached, insert the pea. In bites bypoisonous animals—as venomous serpents, mad dogs, &c., this escharoticmay be used with advantage. Mr. Whateley recommends the potassafusa as the agent for arming caustic bougies to be applied in strictures ofthe urethra; but the practice appears so dangerous (particularly onaccount of the deliquescence and violent action of the caustic), that Ibelieve it is now rarely, if ever, resorted to. There are many other casesin which this substance is employed as a caustic : for example, to destroywarts and fungoid growths of various kinds, and to open abscesses, moreespecially those in the groin; but for the latter purpose the lancet isto be preferred.
(6.) As an antacid we resort to the liquor potassa in various affectionsof the digestive organs, which are attended with an inordinate secretionof acid, known by the acid eructations, cardialgia, and other dyspepticsymptoms. It must, however, be evident, that the neutralization of theacid is merely palliative. But the continued employment of alkalies fre-quently diminishes, temporarily, the tendency to acid secretion. Com-monly it is found that the cases calling for the employment of alka-lies are those benefited by tonics, and hence I believe the alkali is, inmost cases, best given in some mild or tonic infusion; such, for example,as the infusion of calumba, or of gentian, or of quassia; the sulphate ofquinia oftentimes disagreeing with the stomach in these cases; besideswhich, it would be decomposed by the alkali. The beneficial effects ofalkalies are said to be particularly observed in those forms of dyspepsiawhich result from the inordinate use of spirituous liquors.
Of course the liquor potassa; would equally neutralize acid which mayhave been accidentally or purposely swallowed; but it is rarely given forthis purpose, on account of its irritant qualities, and because many otheragents (as chalk, whiting, magnesia, and soap) are equally efficacious asantacids, while they are free from the objections which exist in thesecases to the use of the caustic alkalies.
(c.) To modify the quality of the urine , liquor potasses is a mostvaluable agent. I have already stated that, under the employment ofalkalies, not only may the natural acidity of the urine be destroyed, buteven an alkaline property communicated to it; so that, whenever thesecretion of lithic acid, or of the lithates, is inordinate, the alkaliespresent themselves to our notice as chemical agents for counteracting