We may conclude from these facts, that if the moderate exhalation of fat indicates strength, its superabundance is almost always a sign of weakness, and that there is in this point of view a kind of connexion between fatty and serous infiltrations, as I have mentioned before. It should be observed, however, that leucophlegmasia almost always arises from an organic disease of some of the viscera, particularly the heart, the lungs, the liver, the womb, and the spleen; hence it is usually incurable, and death is the consequence of the organic disease. On the other hand, an organic disease rarely accompanies corpulency, which does not prevent a long life. If leucophlegmasia arose only from cellular weakness, I am persuaded that it would not disturb the regularity of the functions. Great fatty collections are oftentimes an effect almost instantaneous of certain circumstances, for example, of atmospheric influence. It is thus that in twenty-four hours, a fog fattens thrushes, ortolans, red-throats, &c. so that they are unable to escape the sportsman. This phenomenon, which is very frequent in autumn, is never so striking in the human species. The diminution of the fat is as frequent as its increase, and it may be said that there are more cases of extreme emaciation than of remarkable corpulency. The causes which diminish this fluid are these: 1st. long abstinence; the necessary fasting and sleep of dormant animals, furnish us with an example of this; so that in this point of view, fat is the nourishment which is reserved for the time when the ordinary kind is taken away; 2d. every organic disease, continued for a long time, as phthisis, cancer of the pylorus and womb, disorders of the liver, of the heart, &c.; those who are in the habit of examining bodies can judge by the external appearance, without knowing the previous disease, whether the organization of an essential part is changed. In general, in organic affections, there is not only emaciation, but also an alteration in the nutrition of the organs; they are more slender than usual. On the other hand, after an acute fever that has lasted only a few days, emaciation only is observed; nutrition, a function that is deranged as it is exercised, that is to say, slowly, is not yet sensibly affected. There is in this respect a great difference between two bodies equally emaciated; it is sufficient, in most cases, to dissect a limb of each, without seeing the internal viscera, to determine if death has been the gradual effect of an organic disease, or the sudden result of a bilious or putrid fever, &c. To the causes already pointed out, we must add, 3d. every considerable purulent collection, especially if it depends upon a chronic affection; 4th. leucophlegmasia, though we must not believe that fat and serum mutually exclude each other, since we often observe much sub-cutaneous fat in dropsical subjects; 5th. all melancholy affections of the mind which