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ELEMENTS OF MATERIA MEDICA.

kind, than the result of the absorption. In calculous complaints, ammo-nia and its carbonate may be used with considerable advantage in thosecases where potash and soda are serviceable; from which I think itprobable that, like the fixed alkalies, ammonia taken into the stomachis evolved by the kidneys.

Uses. —We resort to a solution of ammonia, property diluted, on avariety of occasions, some only of which can be here noticed.

1. To neutralize acid. —In dyspeptic complaints, accompanied withpreternatural acidity of stomach and flatulence, but without inflamma-tion, a property diluted solution of ammonia may be employed with atwo-fold object—that of neutralizing the free acid, and of stimulating thestomach. It must be remembered that the healthy secretions of thestomach are of an acid nature, and that the continued use of ammonia, orany other alkali, must ultimately be attended with injurious results, moreespecially to the digestive functions. While, therefore, the occasionalemployment of alkalies may be serviceable, their constant or long-con-tinued use must ultimately be deleterious.

Ammonia may, under some circumstances, be employed to neutralizeacids introduced into the stomach from without, as in poisoning by themineral acids, though chalk and magnesia would be more appropriate,being less irritant. It is a valuable antidote in poisoning by hydrocyanicacid. Its beneficial operation has been ascribed to the union of thealkali with the acid, thereby forming the liydrocyanate of ammonia;but since it has been found that this salt is highly poisonous, it isevident that this explanation is not satisfactory. Some have ascribedthe activity of the hydrocyanate to its decomposition by the freeacids of the stomach, and the consequent evolution of free hydro-cyanic acid, but the explanation is unsatisfactory. 1 believe the efficiencyof ammonia as an antidote to poisoning by hydrocyanic acid, arises fromits exerting an influence of an opposite nature to that of the poison. Inpoisoning by the oil of bitter almonds, or other agents supposed to con-tain this acid, ammonia is equally serviceable. The remedy should begiven by the stomach, if the patient can sw’allow, and the vapour shouldbe cautiously inhaled.

2. To produce local irritation, rubefaction, vesication, or destruction ofthe part. —As a local agent, ammonia has been employed in a variety ofdiseases, sometimes as a rubefacient or irritant, sometimes as a vesicant,and occasionally as a caustic. Thus it is employed as a rubefacient inrheumatic and neuralgic pains, and as a counter-irritant to relieve inter-nal inflammations. As a local irritant, a w r eak solution has been injectedinto the vagina and uterus, to excite the catamenial discharge ; but thereare some objections to its use. Thus, it is a most unpleasant kind ofremedy, especially to young females ; moreover, the stoppage of this dis-charge is in many cases dependent on constitutional or remote causes,and, therefore, a topical remedy is not likely to be beneficial. Lavagnaemployed ten or fifteen drops of the solution diluted with milk. Thefollowing is Nisato’s formula:—

jt Ammon, liquid, gtt. xl.; Decoct. Hordei, unc. viii.; Mucilag. arab . unc. dimid.

Misce, et fiant quatuorintra diem injectiones.

Sometimes ammonia is employed as a vesicatory ; and it has twoadvantages over cantharides—a more speedy operation, and non-affectionof the urinary organs. It may be employed in the form of ointment or