Dr. Hart has made a definite contribution to electrocardiographic literature in this book. To the physician in hospital or general practice the variations in rate, rhythm and conduction are presented in an interesting and comprehensive manner. The preliminary discussion of cardiac physiology and pathology and their relation to graphic methods of registration furnishes the student with the information necessary for the proper interpretation of polygraphic and electrocardigraphic records. A description of the instruments employed and of the details of their manipulation are available from other sources and have been wisely omitted by the author; so also have many theoretical considerations which still belong to the sphere of experimental cardiac pathology.
Bradycardia, tachycardia, heart block, extrasystoles, flutter and fibrillation are discussed with regard to their mechanism, experimental production, pathology, etiology, symptoms, identification and clinical significance. The presentation of the subject matter is clear and systematic. References are frequently made to the