When we spoke of Cathartics, we explained at some length their advantages in relieving congestions of the viscera and the head. In this way they are well adapted for the relief of fever; and that article, as well as its application, was formed long before the appearance of Dr. Hamilton's work. In fact, for more than twenty years we have given cathartics freely in fevers, with the most salutary effects; and we consider them as medicines of the greatest importance. In the larger number of epidemics, though active in their operation, they do not weaken the patient, for they take away the cause of, at least apparent, weakness; and we have often found patients in fevers taking bark and wine in profusion, to support them under this apparent debility, who, after the operation of an active laxative, required neither. Let not the young practitioner be terrified by the number of evacuations, but attend to the effects, and to his patient's feelings. If he is relieved after each stool, if the pulse becomes softer, the hand more moist, and the head less loaded, he need not be apprehensive, however violent the discharge. On the contrary, if the pulse becomes smaller and more frequent, if the face sinks, and faintness comes on, however little the discharge, it has been too much. We trust, that when we have laid down this obvious criterion, we shall not be acccused of pushing a theory too far: we have at least given an antidote, should we have administered a poison.

It is necessary, however, in the employment of this remedy, to attend to the discharges. The nurses will often report frequent, numerous evacuations; and if examined, these may be found mucous and inefficient, or a watery fluid, scarcely coloured. It is necessary that the stools should be truly feculent; and these should be continued while any tension can be felt in the epigastrium and abdomen, or while the discharges continue to be dark and offensive. Such they always are in the early stages of fever.

The use of cathartics in fever was the practice of the most ancient physicians; and they were apparently disused, in consequence of the idea that they prevented the discharge by sweating. Hippocrates and his followers depended more on clysters and suppositories. In fact, they had only the more violent cathartics, as the milder ones were introduced by the Arabians; and these very active medicines were injurious by the debility they occasioned. Hippocrates, Galen, Aretaeus, and their followers, employed purgatives early; and their chief reason was to prevent the diarrhoea, which would, they supposed, supervene on the fourteenth day, when the patient would be too weak to bear the discharge. The methodic sect only discouraged their use; but they apparently supplied the defect by enjoining strict abstinence for the first three days. In more modern times, Borelli, Baglivi, Donckers, Sydenham, etc. etc. employed them, though we suspect not to the extent which we have found salutary. Fevers, however, in different situations may greatly differ; and we would anxiously deprecate the application of the practical rules suggested in one situation to diseases of a different country, without exact attention and a due discrimination of the circumstances. We suspect, however, that this class of remedies will always be found very important auxiliaries in fevers of almost every climate.

The choice of the purgative is of some importance. The more violent drastics debilitate too powerfully; and, on the other hand, the salts, the castor oil, the tamarinds, and manna, appear not to excite the action of the moving fibres of the intestines sufficiently to evacuate the more hardened contents. The purgatives which we have found most effectual are, the senna, with a small proportion of the scammony; or the jalap, generally united with the cream of tartar, sometimes with calomel. Nearly similar in effects is a mixture of rhubarb, with some neutral, in equal quantities.

It has been too common to depend on clysters; and in those fevers where Dr. Hamilton has with so much success procured numerous motions, we have known practitioners of eminence content with daily clysters, if stools did not otherwise occur. In general, clysters evacuate only the contents of the rectum, unless they are of a highly stimulating nature, where their peculiar irritation is communicated to the superior portion of the canal; and clysters of warm water, and the usual preparations for this purpose, are inert and inefficient remedies. They certainly give some relief; but this is temporary only, and far inferior to that procured by the operation of an active cathartic. In cases of great debility, where we are apprehensive of the effects of a too copious evacuation, clysters only can be employed.

Diaphoretics are remedies of equal utility; but unfortunately they have been improperly chosen, and the process has been most erroneously conducted. The only salutary discharge from the skin, as we have already explained, is the halitus in the form of gas, or rather of a thin, probably of a vesicular, vapour. When in a fluid state, it increases the oppression it was intended to relieve. This salutary diaphoresis is inconsistent with increased heat; and to promote it in fevers, the heat must be diminished as near as possible to the standard of health. Cooling medicines are consequently the most effectual diaphoretics; and cold water one of the most powerful. Nitre and the other neutrals act chiefly in this way; and the citras potassae, the common saline draught, which it is usual to ridicule, certainly refreshes the feverish patient by the coolness which it imparts to the stomach. Vegetable acids produce a similar effect; and of these vinegar is preferred, as more powerful in its action on the skin. The native acids (the acid fruits) are, from their coolness, salutary and refreshing, and moderate the heat to the proper degree for this discharge. The mineral acids act, we think, differently; and, if the febrifuge spirit of Glutton is useful, it probably is so in an advanced period of fevers of the lowest kind: the spirit of salt, recommended so warmly by Recht, is certainly not referrible to this head.