Part H.

Materia Medica.

17

Lewis also remarks, that decoctions of aloes let fall a precipi-tate, as they cool, probably from extractive being more solu-ble in boiling than in cold water. He also found the hepa-tic aloes to contain more resin and less extractive than the so-cotorine, and this less than the caballine. Trotnsdorff, on thecontrary, gives 81.25 extractive, 6.25 resin, and 12.50 albumen,as the constituents of hepatic aloes. Boulduc also found in so-cotorine aloes J, and in hepatic aloes § of resin. The resins ofall the sorts, purified by alcohol, have little smell; that obtainedfrom the socotorine has scarce any perceptible taste; that ofthe hepatic, a slightly bitterish relish; and the resin of the ca-balline, a little more of the aloetic flavour. The extractiveobtained separately from any of the kinds, is less disagreeablethan the crude aloes : the extractive of socotorine aloes hasvery little smell, and is in taste not unpleasant; that of the he-patic has a somewhat stronger smell, but is rather more agree-able in taste than the extract of the socotorine : the extrac-tive of the caballine retains a considerable share of the pecu-liar rank smell of this sort of aloes, but its taste is not muchmore unpleasant than that of the extractive obtained from the.two other sorts..

Medical use. —Aloes is a bitter stimulating purgative, ex-erting its action chiefly on the rectum. In doses of from 5 to15 grains it empties the large intestines, without making thestools thin ; and likewise warms the habit, quickens the circu-lation, and promotes the uterine and hasmorrhoidal fluxes. Ifgiven in so large a dose as to purge effectually, it often occa-sions an irritation about the anus, and sometimes a dischargeof blood.

It is frequently employed in cases of suppression of themenses, or of the hemorrhoidal discharge; but it is particu-larly serviceable in habitual costiveness, to persons of a phleg-matic temperament and sedentary life, and where the stomachis oppressed and-weakened. For its use in typhus fever, scar-latina, cynanche maligna, marasmus, chlorosis, haemateme-sis, chorea, hysteria, and tetanus, Dr Hamilton's excellentwork on Purgatives may be consulted. Aloes is also usedas an anthelmintic, both given internally and applied to theabdomen in the form of a plaster. Dissolved in alkohol, it isemployed to check hasmorrhagies in recent wounds, and as adetergent in ulcers.

Some are of opinion, that the purgative virtue of aloes re-sides entirely in its resin ; but experience has shewn, that thepure resin has little or no purgative quality, and that the ex-