The great arterial trunks winding in the glands, communicate to them an internal motion very favourable to their functions. This motion is so much the more evident, as almost all these organs very near the heart by their position in the trunk, are, if we may so say, under the immediate jar of its contractions. The salivary glands, the mucous ones of the mouth and the lachrymal on the one hand, the testicle, the prostate and the mucous ones of the genital parts on the other, exhibit the extremes of this position. Another cause which favours the jar of the glands by the entrance of the blood, is that almost all the arteries that go to them run but a very short course before they enter them. The spermatic alone is an exception to this rule; thus, every thing in the secretion of semen seems to be characterized by a remarkable slowness. To this constant motion imparted to the glands by the entrance of the blood, should be added that which is communicated to them by the neighbouring organs, and which keeps them in a constant excitement, which is more necessary to their secretion than to their excretion. In considering the action of organs, the constant motions with which they are agitated has been too much neglected. The example of the brain ought however to fix the attention of physiologists upon this point. The veins, everywhere continuous with the arteries, follow the same distribution in the glandular system, and accompany them almost everywhere. We do not see superficial and deep-seated veins, as we do in many other organs. The liver is the only example in which the red blood enters at one side, and the black goes out at the opposite. Most of the veins of the glandular system pour their blood into the general system of black blood, and as many glands are very near the heart, they feel the reflux which this system often experiences. This phenomenon is particularly remarkable in the liver, as the hepatic veins open but very little below the right auricle. Hence why whenever this auricle is considerably distended, as in asphyxia and in death in which the lungs being crowded present an obstacle to the blood, the liver has a much greater quantity than usual. I have uniformly made this observation. Weigh comparatively this organ when the auricle is full and when it is empty in the dead body, after having first tied all its vessels; you will find a very great difference. For the same reason, you will observe a constant relation between the weight of the liver and that of the lungs, provided a morbid alteration of texture of one of them be not the cause of death. The veins of many glands, as those of the mucous ones of the stomach and the intestines, as those of the prostate, &c. pour their blood into the system of abdominal black blood. There are hardly any in the system of which we are treating, but these veins, those especially of the glands situated in the pelvis, which become varicose. Varices of the prostate are frequent, as we know.