Shall I speak of the innumerable influences that the liver, the kidney and the pancreas receive? When an organ is diseased in the animal economy, these immediately perceive it; their secretion is increased, diminished or altered, and oftentimes even the sympathetic affection does not extend to these functions, but produces inflammation, suppuration, &c. We know that abscesses are formed in the liver from wounds in the head, &c. Shall I speak of the innumerable varieties of the flowing of tears in acute diseases, in inflammatory and malignant fevers, &c.? Who does not know that the eye is then more or less moist, that it is often constantly weeping? Now whence arise these varieties? from the sympathetic influence which the lachrymal gland receives. The disease itself is often foreign to it; but the unknown consensus which connects the glands with the diseased parts, makes them then enter into action. We weep from a variety of passions, from grief especially; how does this happen? Because the influence of the passion is first carried to the epigastric region, as the violent sensation experienced there, proves; and the affected organ reacts upon the lachrymal gland. We weep in the same way as we sweat from fear, or spit copiously in anger, a phenomenon which the vulgar express by these words, _foaming with rage_.
The testicles and the prostate are much less often sympathetically influenced in diseases than the other glands. Whilst every thing is disturbed in the glandular system, they most frequently remain calm and tranquil. Why? because they are insulated by their functions from the other glands. The salivary glands, the pancreas, the kidneys, the liver and almost all the mucous glands contribute to one common object, viz. digestion. This object is connected with the existence of most of the other organs. When these are diseased, it is not wonderful that the glands feel it. On the contrary, the testicles, destined only to the purpose of generation, entering later into action and ceasing to act sooner than the other glands, having great intermissions in their action, cannot in their affections be thus connected with the diseases of the other organs. Sometimes however they are. We know that some affections of the lungs dispose to venereal pleasures; that in a natural state, a lively excitement of certain parts of the skin, of that of the glutæi muscles especially brings into activity the whole genital system, &c. &c.