The system, in certain states of malignant fever, resembles a man struggling beneath a load of two hundred weight, who is able to lift but one hundred and seventy-five. In order to assist him it will be to no purpose to attempt to infuse additional vigour into his muscles by the use of a whip or of strong drink. Every exertion will serve only to waste his strength. In this situation (supposing it impossible to divide the weight which confines him to the ground) let the pockets of this man be emptied of their contents, and let him be stripped of so much of his clothing as to reduce his weight five and twenty or thirty pounds. In this situation he will rise from the ground; but if the weights be abstracted suddenly, while he is in an act of exertion, he will rise with a spring that will endanger a second fall, and probably produce a temporary convulsion in his system. By abstracting the weights from his body more gradually, he will rise by degrees from the ground, and the system will accommodate itself in such a manner to the diminution of its pressure, as to resume its erect form, without the least deviation from the natural order of its appearance and motions. It has been said that the stimulating remedies of bark, wine, and the cold bath, were proper in our late epidemic in August, and in the beginning of September, but that they were improper afterwards. If my theory be just, they were more improper in August and the beginning of September, than they were after the disease put on the outward and common signs of inflammatory diathesis. The reason why a few strong purges cured the disease at its first appearance, was, because they abstracted in a _gradual_ manner some of the immense portion of stimulus under which the arterial system laboured, and thus gradually relieved it from its low and weakening degrees of depression. Bleeding was fatal in these cases, probably because it removed this depression in too sudden a manner. The principle of the gradual abstraction, as well as of the gradual application of stimuli to the body, opens a wide field for the improvement of medicine. Perhaps all the discoveries of future ages will consist more in a new application of established principles, and in new modes of exhibiting old medicines, than in the discovery of new theories, or of new articles of the materia medica.