Mr. Henry Earle[287] has published a very interesting case in illustration of this principle. The arm of a person became paralytic, in consequence of an injury of the axillary plexus of nerves from a fracture of the collar bone; upon keeping the limb for nearly half an hour in a tub of warm grains, ‘_which were previously ascertained by the other hand not to be too hot_,’ the whole hand became blistered in a most alarming manner, and sloughs formed at the extremities of the fingers, and underneath the nails; a considerable degree of inflammation subsequently spread in the course of the absorbents, and matter formed in the axilla, which was soon absorbed, and the inflammation assuaged. Whence it follows, that a limb deprived of its usual supply of nervous energy cannot sustain, without injury, an elevation of temperature which would not be in the least prejudicial to a healthy member. Mr. Earle supports this conclusion by the relation of another case, in which the ulnar nerve had been divided, for the cure of a painful affection of the arm; the consequence of which operation was, that the patient was incapable of washing in water at a temperature that was quite harmless to every duly vitalized part, without suffering from vesication and sloughs. Before we quit the subject of DOSE, it may be necessary to observe, that there are many remedies that do not act with greater violence in a large dose than in one comparatively small; _Ipecacuan_, for instance, is more certain in its operation, but not more violent, when given in a large quantity; the same may be said of _Aloes_, and several other medicines. THE VARIABLE ACTIVITY OF A MEDICINE should also be appreciated, and perhaps the practitioner would act cautiously if he were to reduce the dose, should it be a very considerable one, whenever a fresh parcel of the medicine is commenced, especially of the powders of active vegetables liable to deterioration from being kept, as those of _Digitalis_, &c. THE TIME OF THE DAY at which remedies should be administered deserves likewise some attention. _Evacuating Medicines_ ought to be exhibited late at night or early in the morning. It would seem that during sleep the bowels are not so irritable, and consequently not so easily acted upon, which allows time for the full solution of the substance; the same observation applies to _Alterative_ and other medicines which are liable to suffer from a vexatious irritability of the bowels; it is on this account eligible to exhibit _Guaiacum_, _Pilulæ Hydrargyri_, &c. when they are not intended to purge, at bed time. On the other hand, where the effects of a remedy are likely to be lost by perspiration, as is the case with _Diuretics_, many of which are by external heat changed into _Diaphoretics_, it may become a question with the judicious practitioner whether he cannot select some more favourable period for their exhibition.