Despite great ferment and activity among historians of science in recent years, the history of physiology after 1850 has received little attention. Gerald Geison makes an important contribution to our knowledge of this neglected area by investigating the achievements of English physiologists at the Cambridge School from 1870 to 1900. He describes individual scientists, their research, the scientific issues affecting their work, and socio-institutional influences on the group. He pays special attention to the personality and contributions of Michael Foster, founding father of the Cambridge School. Foster's specific research interest was the origin of the rhythmic heartbeat, and the author contends that the school itself descended from and developed around this concern. Originally published in 1978. The Princeton Legacy Library uses the latest print-on-demand technology to again make available previously out-of-print books from the distinguished backlist of Princeton University Press. These editions preserve the original texts of these important books while presenting them in durable paperback and hardcover editions. The goal of the Princeton Legacy Library is to vastly increase access to the rich scholarly heritage found in the thousands of books published by Princeton University Press since its founding in 1905.