FORMERLY SCHOLAR OF EXETER COLLEGE, OXFORD PERCIVAL & CO. KING STREET, COVENT GARDEN London 1890...

It is hoped that the account given, in the following pages, of the lives of five great naturalists may not be found devoid of interest. The work of each one of them marked a definite advance in the science of Biology. There is often among students of anatomy and physiology a tendency to imagine that the facts with which they are now being made familiar have all been established by recent observation and experiment. But even the slight knowledge of the history of Biology, which may be obtained fr

Owing to the lapse of centuries, very little is known with certainty of the life of Hippocrates, who was called with affectionate veneration by his successors "the divine old man," and who has been justly known to posterity as "the Father of Medicine." He was probably born about 470 B.C. , and, according to all accounts, appears to have reached the advanced age of ninety years or more. He must, therefore, have lived during a period of Greek history which was characterized by great intellectual a

About the time that Hippocrates died, Aristotle, who may be regarded as the founder of the science of "Natural History," was born ( B.C. 384) in Stagira, an unimportant Hellenic colony in Thrace, near the Macedonian frontier. His father was a distinguished physician, and, like Hippocrates, boasted descent from the Asclepiadæ. The importance attached by the Asclepiads to the habit of physical observation, which has been already referred to in the life of Hippocrates, secured for Aristotle, from h

Under the Ptolemies a powerful stimulus was given to biological studies at Alexandria. Scientific knowledge was carried a step or two beyond the limit reached by Aristotle. Thus Erasistratus and Herophilus thoroughly investigated the structure and functions of the valves of the heart, and were the first to recognize the nerves as organs of sensation. But, unfortunately, no complete record of the interesting work carried on by these men has come down to our times. The first writer after Aristotle

The authority of Galen, at once a despotism and a religion, was scarcely ever called in question until the sixteenth century. No attempt worth recording was made during thirteen hundred years to extend the boundary of scientific knowledge in anatomy and physiology. It is true that the scholastic philosopher, Albertus Magnus, who was for a short time (1260-1262) Bishop of Ratisbon, in the middle of the thirteenth century wrote a "History of Animals," which was a remarkable production for the age

The importance of Harvey's discovery of the circulation of the blood can only be properly estimated by bearing in mind what was done by his predecessors in the same field of inquiry. Aristotle had taught that in man and in the higher brutes the blood was elaborated from the food in the liver, conveyed to the heart, and thence distributed by it through the veins to the whole body. Erasistratus and Herophilus held that, while the veins carried blood from the heart to the members, the arteries carr