PREFACE TO SECOND EDITION 



IN preparing a second edition of my Essentials of Physi- 

 ology, I have endeavoured to bring the information up to 

 date, and to increase the usefulness of the book by rearrang- 

 ing and extending certain sections and by the introduction 

 of many additional figures. 



The purpose and character of the book remain unchanged. 

 It pretends to give no more than the Essentials of Human 

 Physiology, and it is not intended to replace, but only to 

 supplement the practical work and demonstrations from 

 which alone a real knowledge of the subject can be gained. 

 To facilitate the linking of systematic and practical study, 

 references are given to the practical work which the student 

 should do as described in Schafer's Class Work in Prac- 

 tical Physiology, and in the author's Practical Course of 

 Elementary Chemical Physiology. 



My thanks are due to Dr. Goodall and to Mr. Graham 

 Brown, B.Sc., for the new illustrations, and to Dr. I. Cameron 

 for reading the proof-sheets and revising and extending the 

 Index. 



D. N. P. 



