The most conspicuous feature in the life of the Indian races is their division into castes, of which the most noble is that of the priests, or Brahmins, who in ancient times alone had the privilege of practicing medicine. Their Organon of Medicine, or collection of medical knowledge, was a hook which they called _Vagadasastir_. It was not systematically arranged, and in it demonology played a large rôle. They held the human body to consist of 100,000 parts, of which 17,000 were vessels, each one of which was composed of seven tubes, giving passage to ten species of gases, which by their conflicts engendered a number of diseases.{005} They placed the origin of the pulse in a reservoir located behind the umbilicus. This was four fingers wide by two long, and divided into 72,000 canals, distributed to all parts of the body. The physician examined not only the pulse of his patient, but the dejecta, consulted the stars, the flight of birds, noted any incidental occurrence during his visits, and made up his prognosis from a multitude of varying circumstances, omitting only those which were really valuable, namely, the symptoms indicating the state of the organs. Ancient Hindoo charlatan priests let fall from the end of a straw a drop of oil into the patient's water. If the oil was precipitated and attached itself to the bottom of the vessel, they predicted an unfavorable result; if, on the contrary, it floated, they gave a favorable prognosis. This is, so far as we know, the earliest recorded way of testing the specific gravity of the urine. With all their absurdities, however, the Indians appear to have done some things that we scarcely do to-day: they arè said to have had an ointment that caused the cicatrices of variola to disappear, and they cured the bites of venomous serpents with remedies whose composition has been lost.