WILLIAM H. HOWELL, PH.D., M. D. Professor of Physiology in the Johns Hopkins University, Baltimore, Md. BOSTON MEDICAL LIBRARY IN THE SECOND EDITION, REVISEPRANCIS A. COUNTWAY LIBRARY OF MEDICINE VOL. I. BLOOD, LYMPH, AND CIRCULATION; SECRETION, DIGESTION, AND NUTRITION; RESPIRATION AND ANIMAL HEAT; PHILADELPHIA W. B. SAUNDERS & COMPANY 1900 CONTRIBUTORS TO VOL. I. JOHN G. CURTIS, M. D., Professor of Physiology in Columbia University (College of Physicians and Surgeons). W. H. HOWELL, PH. D., M. D., Professor of Physiology in the Johns Hopkins University. GRAHAM LUSK, PH. D., F. R. S. (EDIN.), Professor of Physiology in the Yale Medical School. W. T. PORTER, M. D., Assistant Professor of Physiology in the Harvard Medical School. EDWARD T. REICHERT, M.D., Professor of Physiology in the University of Pennsylvania. 3 PREFACE TO THE SECOND EDITION. ADVANTAGE has been taken of the necessity of issuing a second edition of the American Text-Book of Physiology to alter somewhat its general arrangement. The book has proved to be successful, and for the most part has met only with kindly and encouraging criticisms from those who have made use of it. Many teachers, however, have suggested that the size of the book, when issued in a single volume, has constituted to some extent an inconvenience when regarded from the standpoint of a student's text-book that may be needed daily for consultation in the lecture-room or the laboratory. It has been thought best, therefore, to issue the present edition in two volumes, with the hope that the book may thereby be made more serviceable to those for whose aid it was especially written. This change in the appearance of the book has necessitated also some alteration in the arrangement of the sections, the part upon the Physiology of Nerve and Muscle being transferred to the second volume, so as to bring it into its natural relations with the Physiology of the Central Nervous System. The actual amount of material in the book remains substantially the same as in the first edition, although, naturally, very many changes have been made. Even in the short time that has elapsed since the appearance of the first edition there has been much progress in physiology, as the result of the constant activity of experimenters in this and the related sciences in all parts of the world, and an effort has been made by the various contributors to keep pace with this progress. Statements and theories that have been shown to be wrong or improbable have been eliminated, and the new facts discovered and the newer points of view have been incorporated so far as possible. Such changes are found scattered throughout the book. The only distinctly new matter that can be referred to specifically is found in the section upon the Central Nervous System, and in a short section upon the modern ideas and nomenclature of physical chemistry, with reference especially to the processes of osmosis and diffusion. The section dealing with the Central Nervous System has been recast in large part, with the intention of making it more suitable to the actual needs of medical students; while a brief presentation of some of the elementary conceptions of physical chemistry seems to be necessary at the present time, owing to the large part that these views are taking in current discussions in physiological and medical literature. The index has been revised thoroughly and considerably amplified, a table of contents has been added to each volume, and numerous new figures have been introduced. AUGUST, 1900. 5 |