Page:The Harveian Oration1876.djvu/23

 time and order, and at last arrived at so perfect a knowledge of the intricate movements of the heart that he left really nothing for his successors to do. That formed, then, the first part of his great work, and gave the first words to its title, “De Motu Cordis.”

No doubt years had passed before he had made all this out. Engaged in practice, married, and a few years later becoming physician to St. Bartholomew’s Hospital, he can have had but little time for these researches.

At length, all was clear about the heart, and he had, in addition, carefully determined the total quantity of blood in the body of animals. He had also found our the action of the cardiac valves, and was acquainted with the valves in the veins; and now there came the next step. He nowhere precisely tells us, but he seems to have kept the whole facts before him, just as Newton tells us he did with his great discoveries, until light began to dawn. To us who are so familiar with the circulation