Employed as a remedy, there is no degree of burning heat which the animal economy is capable of producing, no intensity of vascular action, and no violence of pain that can resist its continued application. Sooner or later, usually in from ten to twenty minutes, the heat, though most intense, disappears, the skin becomes cold, the face pallid, the features shrunk, while the pulse is reduced to a mere thread, and the pain of the head, however violent and intolerable, entirely ceases. After the patient has been wiped dry, which he should be as rapidly as possible, and placed in bed, the symptoms may soon return in all their violence; the same process will again remove them, and as often as the former recur the latter must be repeated. Three or four repetitions will commonly suffice to subdue the most intense cerebral affection. In the case of Dr. Dill, the relief it brought was instantaneous and most complete. From a state of intense suffering it rendered him perfectly easy, and from a state of imminent danger, safe. I had no anxiety about him from the moment he came out of his tub, although it was necessary to pass him through the same ordeal three times; but he himself having tried this remedy on his sister, having in her case witnessed its efficacy, and now felt it in his own, was extremely desirous that it should be repeated as soon as he was conscious of any return of pain. In consequence of its application, together with the copious depletion that preceded it, at the period when under ordinary treatment, the most exquisite typhoid symptoms would have been present, he was convalescent.[36] If we consider how powerful the abstraction of caloric must be by every fresh current of water that falls upon the head, to what a mere thread the minute external blood-vessels must be constringed, and consequently to what an extent the internal must be affected, we shall not wonder at its efficacy. Powerful as the cold affusion is when exhibited in its ordinary mode, yet the impression it makes upon the brain, compared with the effect produced by this remedy, may be said to be what the application of six leeches to the temples is to the abstraction of thirty ounces of blood. Cold applications to the head, and evaporating or iced lotions, are useful in mild cases; they may keep up the effect produced by this in the more severe, but to hope to control the latter by their aid alone, is to expect to coerce a giant, by twisting around his arms a spider’s thread. II. OF THE MODIFICATION OF TREATMENT IN THORACIC AFFECTION.