PKEFAOE TO THIED EDITION. 



THIS edition contains about seventy-six more pages than the 

 second. Several old cuts have been removed. Twenty-five more cuts 

 have also been inserted. The chapters upon Blood, Circulation, and 

 Metabolism have been entirely rewritten. Inspiration and Glands 

 with an internal secretion have been revised to a considerable extent. 

 Many facts in Applied Physiology and Therapeutics have been inserted 

 for the benefit of the practitioner. The difficult things in Physiology 

 have been made plain to the student. Discordant and hypothetical 

 discussions have been avoided, which saves time for the reader. The 

 theory usually accepted has been given. The greatest number of facts 

 has been expressed with the smallest number of words, for Physiology 

 is a positive science. I have not given any physiological technique, as 

 it is in the laboratory and not in the text-book that the student should 

 learn it. My thanks are due to Dr. John C. Scott, Demonstrator of 



Physiology, for the re-paging of the index. 



ISAAC OTT. 



(v) 



