PREFATORY NOTE vii 



To Messrs, the Cambridge and Paul Scientific Instrument Co. 

 for the figures illustrating the electro-cardiograph (Figs. 64-67) ; 

 to Messrs. Hawksley for those of the viscosimeter (Figs. 77 and 82) 

 and to Messrs. Gallenkamp for Figs. 2 and 3 of the bomb calori- 

 meter. 



The remaining forty illustrations were drawn by Dr. G. M. 

 Wishart, Assistant in the Department of Chemical Physiology, and 

 by Mr. John Waters, a student of medicine here. To their skill 

 and care I owe much. 



I am greatly obliged to Mr. A. V. Steen, B.Sc., one of our 

 demonstrators, for reading all the proofs. The freedom of the 

 matter from certain errors is the result of his painstaking efforts. 



Finally, I desire to record my gratitude to my publishers for 

 their patience and courtesy during the prolonged period of 

 publication and to the printers for the care they have taken and 

 the consideration shown when my ignorance made large demands 

 on their time and patience. 



INSTITUTE OF PHYSIOLOGY, 



UNIVERSITY OF GLASGOW. 



