Page:The growth of medicine from the earliest times to about 1800.djvu/427

 thirty years later), Harvey had the satisfaction of witnessing the almost unanimous acceptance of his dogma concerning the circulation of the blood. Louis the Fourteenth, King of France at this period, was so appreciative of the importance of Harvey's discoveries that he appointed Dionis, the distinguished French anatomist, to demonstrate to the students of the Medical School of the Jardin des Plantes at Paris the circulation of the blood and other recent discoveries. Descartes (1596-1650), the celebrated French philosopher, paid an even greater compliment to the high character of the work accomplished by Harvey. His words, as quoted by Flourens, are as follows:—

If I am asked why the supply of venous blood does not become exhausted in flowing thus unceasingly into the heart, and why the arteries—since all the blood that passes through the heart must travel along these vessels—do not become filled to overflowing, I can see no good reason why I should not give to this question the very same answer that William Harvey, an English physician, to whom praise is due for having taught, has already given. [Then follows the text of Harvey's reply.]

Our readers have doubtless noted the fact that, while Harvey, as I have endeavored to show in the preceding account, has clearly established his right to be considered the discoverer of the circulation of the blood in all its most essential features, his scheme fails to furnish any information concerning the composition of the blood and the manner in which it is built up into a life-giving fluid. In the minds of some this may seem to be an omission. A moment's reflection, however, will satisfy any reasonable person that questions of this nature do not form a legitimate part of the problem which Harvey was engaged in solving, and that they therefore should receive separate consideration. Thus, for example, Harvey's scheme fails to furnish satisfactory information concerning those portions of the circuit where the blood is obliged to travel through a system of communicating capillary channels, as happens in the lungs and in the tissues generally throughout the body. But Harvey had no means at his command