A. The fluids of the body have been classed according to their form, or their qualities. In the former view, they may be arranged under the heads of gaseous, watery, oily, glairy, or mucous. The gaseous fluids are the insensible perspiration from the surface, and the lungs; some gas combined loosely with the blood; the contents of the pericardium; of the ventricles of the brain; of the duplicature of the peritonaeum, perhaps of the sheaths of the nerves; more certainly of the stomach and intestines. The watery fluids are, the circulating, the secreted, and the absorbed fluids: the oily, the contents of the adipose membrane, the bile, and cerumen; the glairy, those contained in the cavities of the joints; the mucous, those which line surfaces contiguous to each other, generally such as admit of occasional dilatation for the passage of any body, as the throat, the vagina, &c; often those whose accretion this fluid is designed to prevent, as the eye lids, the prepuce, etc.

Dr. Hooper divides the fluids from their qualities into the crude, more properly the alimentary, as the chyme or chyle; the sanguineous, as the fluids of the heart, arteries, and veins; the lymphatic, or the contents of the lymphatic system; to which he adds the nutri-'ious gelatine; the secreted and the excrementitious.

The secreted fluids may be again divided according to their form, as stated above; but the varieties are numerous, and the shades of distinction often minute. Thus milk unites the watery and the oily; the semen approaches an albumen, and the liquor of the prostate remains to be more accurately examined. The diseases of the fluids are numerous, but must be the subject of a separate consideration. See Morbi fluidorum.