Syn. Spirit of Mindererus. Spiritus Mindereri.

Preparation

This solution is prepared by saturating diluted acetic acid with carbonate of ammonia. The latter is gradually added to the former, until effervescence ceases, and the acetic acid is saturated. The resulting preparation, is a solution of acetate of ammonia, impregnated with carbonic acid, a portion of which is retained by the liquid, when disengaged from the carbonate. it was formerly made with common vinegar, and often impure carbonate of ammonia, and had a dark-brown colour, and empyreumatic odour. it is still occasionally prepared with distilled vinegar; but this is objectionable, as of uncertain strength, and, in consequence of some organic matter contained in it, sometimes causing the liquid to be brown. The solution may, however, be deprived of colour by filtration through animal charcoal.

Properties

When quite pure, it is colourless, and, if the saturation is exact, has no smell. An acetous odour, however, is much preferable to an ammoniacal, as the former would indicate an excess of acetic acid, which, if moderate, is harmless; the latter an excess of the carbonate, which is objectionable on account of its stimulant properties. The taste is saline and disagreeable. By heat, the solution is dissipated, without residue. it is decomposed by solution of potassa and the stronger acids; the former evolving an odour of ammonia, the latter of vinegar. The salts of iron redden it, and, with a solution of nitrate of silver, it causes the formation of crystals of the acetate of that metal. When long kept, with access of the air, it undergoes decomposition, and a portion of carbonate of ammonia is formed. it should be prepared as wanted for use.

Medical Effects and Uses

The solution of acetate of ammonia was known to Boerhaave, but was brought into notice somewhat later by Minderer, whence it derived the name of spirit of Mindererus. it is somewhat sedative or refrigerant in its effects, and operates as a diaphoretic in febrile states of the system. it is said to prove diuretic, if the patient be kept cool, and walk about during its use. Some have supposed it to be stimulant; but there is no sufficient evidence of its possessing that property.

It is used for the same purposes, and in the same complaints as the neutral mixture; but, according to my observation, is greatly inferior to it both in diaphoretic power, and in the property of calming irritability of stomach. in my earlier practice, I used it a good deal in febrile diseases, but found it almost uniformly so much inferior to citrate of potassa, and so much less acceptable to the patient, that I have long ceased to use it, except in those rare cases, in which, from idiosyncrasy of stomach or palate, or unpleasant effects on the bowels, the neutral mixture or effervescing draught could not well be given. it is thought by some to be sedative in its influence on the uterus, and to be beneficially used in painful menstruation.

Locally, it has been thought to possess discutient properties, and been applied by means of compresses upon various kinds of tumours. it has also been used as a collyrium in chronic ophthalmia, being diluted with seven parts of rose-water.

The dose is half a fluidounce every two hours, which may be taken with a fluidounce of sweetened water, or carbonic acid water.