responsible for the very term "hypothesis," which, in its scientific application, he invented.
Some of the experiments of the Hippocratic schools may be considered as the first in the field of experimental physiology, as for example, the feeding at the same time of different kinds of food and the study, after induced vomiting, of the stage of digestion of each. It is, however, in the field of clinical observation that Hippocrates excelled. His inferences were frequently wrong, but his descriptions of the symptoms of a disease, as an aid to diagnosis and prognosis, were at once picturesque and accurate. How accurate and vivid they were may be seen from the fact that the characteristic signs of impending death are still known as the "facies Hippocrates." This exercise of minute observation and accurate interpretation of every symptom—the method of clinical medicine—which has influenced medicine in all succeeding ages, was the beginning of the study of what we now term the "natural history of disease." In therapy Hippocrates recognized the natural tendency to health (vis medicatrix naturæ) and this principle influenced all his therapeutic efforts. In addition to this substantial service to medicine we owe him certain idealistic influences as shown in the Hippocratic oath and in his constant desire to place all knowledge freely and fully before the profession at large.
Certainly medicine under Hippocrates, as contrasted with that of the preceding ages, was magnificent, and it is not surprising that after his death, he was deified. To us he represents the beginnings of an exact medicine, and his influence is seen in many of the theories, methods and ideals of modern practise. Hippocratic medicine, Hippocratic doctrine, Hippocratic oath, are current phrases, and the admonition "Back to Hippocrates" is an admonition to beware of theory and seek the solid ground of observation and experiment.
Between Hippocrates and Galen lie nearly five hundred years without progress in medicine, except as the brilliant Alexandrian school, sheltering Euclid, Archimedes and Ptolemy developed, under Herophilus and Erasistratus, a school of anatomy (ca. 300 B.C.) which established many new anatomical facts. But as Neuburger states in his discussion of early medical theories, "Collection and observation of facts constitute the first step in science, but not science itself." The observation of anatomical facts during these centuries is naturally of some importance in connection with the growth of anatomy, but unfortunately of no importance as regards the influence of those facts on medical theory, for physiology remained a field for speculation while the facts gained from anatomy were used only to strengthen the older speculation and dogmatism, and to rehabilitate discarded doctrines. To the Alexandrian school and to Galen, however, must be given the -credit of a careful study of anatomy by dissection, and this honor is the