This book, the first of two volumes by Lepeschkin, is written in the monumental style of Sir Thomas Lewis and of Wenckebach and Winterberg. It attempts to cover the literature from 1934 to May, 1950; almost 10,000 references are cited. This volume is concerned with the theory of the electrocardiogram and its contour. The author, by virtue of his work in Russia, Austria, and the United States and his contacts with the Wilson school in the United States, is well equipped to bring together the literature of the last 16 years and to show the manner in which electrocardiography has altered since the days of Lewis and the Viennese school. His knowledge of foreign languages makes him particularly adept for his task. His style is Germanic, and the cross references are impressive. A spot-check, however, shows that there are some errors in reference. This is no more than can be