PREFACE 



The Institutes of Medicine, the older and better name for 

 Physiology, are the basis of Medicine ; the investigation of the 

 abnormal subject must be founded upon the study of the healthy 

 organism. The importance of practical physiology is undoubted, 

 but there is considerable difference of opinion as to the nature 

 and scope of the experimental work which is most suitable for a 

 medical student. Nevertheless, it is becoming more clearly recog- 

 nised that the practical work should have a direct relation to 

 medicine and, as far as possible, the experiments should be performed 

 upon man. 



In the present book the authors have given a further extension 

 to practical physiology along these lines. They have built largely 

 upon the foundations of the Practical Physiology by A. P. Beddard, 

 J. S. Edkins, M. Flack, Leonard Hill, J. J. R. Macleod and M. S. 

 Pembrey. The third edition of that book was exhausted two or 

 three years ago, and most of the contributors are no longer engaged 

 in the teaching of physiology to medical students. The present 

 authors wish to thank them heartily for their kind permission to 

 make full use of their contributions. 



The volume is divided into two parts : Part I, Experimental 

 Physiology, Elementary Course by D. Noel Paton, Advanced 

 Course by M. S. Pembrey ; and Part II, Chemical Physiology by 

 E. P. Cathcart. The special chapter upon the " Investigation of 

 the Motor Functions of the Alimentary Canal by Means of the 

 X-Rays," which appeared in the third edition of Practical 

 Physiology, has been revised by its author, Dr. Hurst ; for this 

 valuable contribution hearty thanks are given. 



Figures have been borrowed from The Essentials of Human 

 Physiology, by D. Noel Paton, and from The Physiological Action of 

 Drugs, by M. S. Pembrey and C. D. F. Phillips. For the loan of 

 blocks the authors are indebted to Messrs. Baird and Tat lock, 

 Hatton Garden, E.G., Messrs. William Green and Son, Edinburgh, 

 and Messrs. Henry Frowde and Hodder and Stoughton, London. 



The drawings of crystals were executed by Mr. W. R. M. Turtle 

 for the first edition of Practical Physiology. The sources of other 

 diagrams and tracings, which have been borrowed, are indicated 

 in the description of the figures. The initials of the author, who 

 took the record of the original tracings, are appended to the 

 respective curves. 



