What I have just said of exhalations applies to secretions. The mucous glands pour out a greater quantity of fluids in two ways, sometimes from irritation, sometimes from the want of force. When this happens in the intestines, there results from it in the first case a diarrhœa from irritation, in the second a colliquative one. Now it appears that the blood enters the gland in greater abundance in the one than the other case. Its increase takes place undoubtedly in most acute catarrhs, in which there is active secretion of mucus; its diminution or at least its want of increase is not less sensible in many chronic catarrhs, in which we may consider the secretion as passive. We know that the abundance of urine, of bile, sometimes supposes an increased, sometimes a diminished action of the kidney and the liver. Is there not a superabundance of semen from excess of vitality, and an unnatural flow from weakness? All the secreted fluids have the same arrangement; now according to these two opposite causes of the superabundance of the secreted fluids, the capillary system of the glands is certainly penetrated with a different quantity of blood. Though the phenomenon be the same, the treatment in the diseases in which it is manifest, is as in the preceding cases, wholly opposite, according as the local increase or diminution of life concurs to produce it. _Consequences of the preceding Remarks._ From all that I have said, it is evident that in the organs whose capillary system contains in part blood, and in part different fluids, the proportion of the first to the others is infinitely variable; that a thousand causes in a state of health, as in that of disease, by bringing to the organ more or less blood, can fill more or less its capillary system. The trunks and branches that go to an organ, are they more or less dilated, according as the capillary system of this organ is more or less filled with blood? For example, when the mucous glands pour out fluid in the greatest quantity, are the neighbouring branches more full? Some experiments that I shall mention hereafter do not seem to prove it. IV. _Of the Anastomoses of the General Capillary System._ All that has been said evidently supposes a free communication established between all the parts of the capillary system; this communication is in fact clearly demonstrated by observation. When we examine a serous injected surface, of which the capillary system is full, we see that this system is a real net-work with fine meshes, and in which no vessel runs a distance of more than two lines, without communicating with others. The passage then, is constantly open between the portion that receives blood, and that which admits fluids differing from it. The same arrangement exists in the dermoid system, in the origins of the mucous, &c. and in general in all those in which the capillary system contains blood and white fluids.