Without doubt this is a useful booklet and deserves continued recognition by American clinicians. The first edition appeared in 1932 and was reviewed in the Archives of Internal Medicine (51:640-641 [April] 1933). It was stated that this little volume was an admirable elementary exposition of electrocardiography for the practitioner, and particular praise was given the tracings and diagrams. The third edition is much like the first, with reasonable amplification. Again the illustrations are outstanding and commendable. Again the latest edition continues to be no more than was originally intended, a first rate elementary exposition of electrocardiography for any practitioner interested in cardiac disease.