(From acesco, to sharpen,) acidity, also acor. Diseases from this cause are frequent.

The seat of acidity in our bodies, as a disease, is principally the stomach and the small intestines. An acid acrimony is never sensibly prevalent in the blood; though it sometimes appears in the urine.

An acid acrimony may arise either from too great laxity and debility of the organs of digestion, or from an excess of acescent food. When the digestion is imperfect, an acidity is the consequence, though no such process as fermentation has preceded. The food of children is for the most part of the vegetable kind, and readily turns sour in the stomach, if the body be any way disordered; hence most of their disorders are accompanied with the evident signs of acidity, as green stools, gripes, etc. Many assert a prevailing acid to be the cause of all diseases in children; but acidity in their stomach is more often an effect than a cause of their complaints. It is not acidity, but its excess that injures.

The redundant acid in the primae viae is known by the sourness of the eructations, the frequent cardial-gia, in the stomach flatu/ence, and spasms in the in-tcsrines; the belly is costive, and the nourishment is unduly supplied, a paleness becomes general in the skin, an itching comes on, pustules appear, and a train of nervous symptoms soon succeeds. Indeed, in all diseases peculiar to children, there are, for the most part, symptoms of an excess of irritation: the pulse sometimes beats one hundred, or one hundred and twenty in a minute, the stomach is disordered, the vessels of the skin are contracted, and epileptic or convulsive symptoms appear.

Infants are frequently swept off by this disorder. Among adults, the weakly and sedentary are the only subjects of it, except among the poor, whose scanty supplies reduce them to this unhappy state.

The cure, when adults are the subjects, consists of a diet fitted to oppose this faulty habit; animal food and vegetables of the aromatic kind: these, with moderate exercise at proper intervals, will often succeed with warm tonics. Absorbent medicines may palliate symptoms in the stomach and intestines, but the lima-tura ferri. will most conduce to an effectual and lasting cure. Children should be exercised more, and fed less than is usual. Antimonial emetics, repealed at intervals of two or three days, until the more disagreeable symptoms abate, are highly useful. Small doses of p. rhei, with magnes. alb. so as to keep the belly soluble, is better than more active purging; and small doses should be given frequently. Indeed] in some cases, small doses of fixed or volatile alkali, particularly aqua ammonias, have been highly beneficial, and warm stimulant plasters, applied to the umbilical region, have added to these advantages. Acidity is not peculiar to children, nor does it always depend on the nature of the food. It is a mark of a disordered digestion from many different causes. Curdled milk, ejected, is supposed to be a decisive proof of an acid stomach. This, however, is by no means the case: for the stomach of an infant will curdle milk, when it will not, to the nicest test, discover the slightest particle of acid. A gouty habit, and the pregnant state, will always bring it on; and, in many constitutions, food of every kind will soon become acid, for reasons that we cannot understand. All that can be known is, that the principles of the vegetable acid, for of this nature is the morbid acid of the stomach, arc found in food of every kind, and that, when their union is destroyed in the first periods of digestion, a new compound takes place. Perhaps this always occurs, and the acid is again enveloped or forms a part of another compound, by a subsequent operation. Calcareous and magnesian earths, therefore, only palliate the complaint: the cure depends on strengthening the stomach. As palliatives, in the chronic-cases of acidity, lime-water is one of the best. In-the pregnant state, aq. ammonia; purae is preferable.

See Van Swieten's Commentaries on Boerhaave's Aphorisms. Medicamentorum Formulae, Dris. Hugh. Smith. London Practice of Physic, edit. 6. Armstrong on Diseases fatal to Infants. Moss on the Ma nagement of Children, Sec.