224

ELEMENTS OF MATERIA MEPICA.

Analogous results have been obtained by Courten and Hertwich (quotedby Wibmer) and by Pommer (mentioned by Dr. Christison).

The impure acetic acid obtained by the distillation of wood, has beenusually regarded as possessing much more activity than pure acetic acidof the same strength, in consequence of the presence of empyreumaticoil. An extensive series of experiments have been made with it onamphibials, birds, and mammals, by Berres, Kerner, and Schubarth.From these it appears that pyroligneous acid is a caustic poison; andthat it destroys some of the lower animals, viz. amphibials, merely bycontact with the external sldn. Large doses affect the cerebro-spinalsystem, and cause giddiness, insensibility, paralysis, and convulsions. Avery constant effect was an affection of the windpipe and lungs. Theacid was detected in the blood and secretions by its odour (Wibmer,Wirkung d. Arzneim).

(c.) On man. —In the concentrated state acetic acid is an irritant andcorrosive poison. Its chemical influence depends principally on itspower of dissolving fibrin, albumen, and gelatine, as before mentioned,by which it acts as a solvent of many of the animal tissues. Applied tothe shin it acts as a rubefacient and vesicant. Only one case of poison-ing by its internal use is known. The patient (a girl) appeared to beintoxicated, complained of acute pain, and was violently convulsed( Journ. Chim. Mdd. t. vii).

Swallowed in a very dilute form, and in moderate doses, acetic acidacts in a very analogous manner to the diluted mineral acids (see pp. 80,81, 84, and 96). Thus it is refrigerant, tonic, diaphoretic, and diuretic.Its local operation is astringent. Used moderately it assists the digestiveprocess, and is therefore tahen as a condiment. It is in repute withyoung ladies for diminishing obesity. It is said that the long-continueduse of it, in full doses, will induce chronic diseases of the gastro-intes-tinal mucous membrane; and Morgagni says, it has even given rise toscirrhus of the pylorus.

Vinegar may be tahen in considerable quantity at one time withoutinconvenience. Dr. Christison knew a case in which eight ounces wereswallowed without injury.

The vapour of strong acetic acid is very pungent and irritating. Thelong-continued inhalation of acetic vapours, as by the workmen employedat vinegar-works, is said by Sundelin ( Handb . d. Heilmittellehre) to beinjurious to the lungs, and to bring on chronic inflammation of theseorgans.

Uses. —1. Medicinjl. —Taken internally, common vinegar or aceticacid, properly diluted, is used for various purposes ; the most importantof which are, to allay febrile heat by its refrigerant qualities, to diminishinordinate vascular action, to relieve certain affections of the brain sup-posed to depend on, or be connected with, venous congestion, and to actby its chemical properties of an acid. Thus, in fevers , whether simpleor eruptive, but especially in those varieties commonly denominatedputrid and bilious, vinegar (more or less diluted with water) is a mostrefreshing drink, allaying thirst, and diminishing excessive heat. Inhaemorrhages, as from the nose, lungs, stomach, or uterus, it is particu-larly beneficial by its refrigerant, sedative, and astringent qualities. Itdiminishes excessive vascular action, and promotes contraction of the