But it is also true, that in the very worst sort of fevers in hot climates it is a favourable symptom where the secretion of the liver is restored and increased, a bilious diarrhœa being one of the most auspicious symptoms that can occur in a yellow fever; and in those that are protracted and afford hopes of recovery, there is generally a gush of bile from time to time.--We may therefore lay down the following positions: 1. That in cases in which bile is most freely and copiously secreted no fever exists, as in _cholera morbus_. 2. That in the worst sort of fevers there is no preternatural secretion of bile, but, on the contrary, a defect of it. 3. That nevertheless there is an uncommon quantity of bile secreted in most of the fevers of hot climates, and that part of the cure consists in evacuating it. I am extremely diffident, as I have said, in all matters depending on our supposed knowledge of the animal œconomy; but the preceding circumstances seem to countenance the following reasoning:--The bile, according to Dr. Maclurg, who has given one of the best dissertations on its nature and properties, is composed of two parts; the gross part, which is coagulable by acids, and that part in which the bitter principle resides. The first constitutes the principal part in point of quantity, and seems to be that portion of the mass of fluids which loses the property of sound healthy blood, by a tendency to putrefaction, and is thrown out by this secretion. I will not undertake to vouch for the truth of this, but shall assume it as true in the following reasoning:--According to this theory, therefore, the greater part of the bile is what may be called the effete part of the circulating mass, or perhaps only of the red globules or gluten, the watery and saline part, which passes off by urine being the corrupted part of the serum. This part of the bile being very liable to putrefaction, the bitter part is considered by Dr. Maclurg as intended to correct this, and also to answer some good purpose in digestion. One of the effects of the bile in this operation is to extinguish acidity, whether proceeding from substances taken in, or generated in the stomach. The blood in all climates, and in all situations of life, is subject to have part of it thus corrupted, which, being separated from the common mass by the liver, is mingled and discharged with the common _feces_; but external heat continued for any length of time tends to augment this corruption of the fluids, and therefore to increase the secretion of bile; and it has been observed both by myself and others, that the bile found in those bodies that have been inspected after death, in consequence of fevers in hot climates, is less bitter, and not so penetrating to the fingers, being therefore deficient in the antiseptic principle. But since external heat makes no alteration in the degree of temperature of the fluids themselves, this effect must take place through the medium of the solids, in