

Copyright, 1907, by W. B. Saunders Company. Revised, entirely reset, reprinted and 



recopyrighted February, 1914. Revised, entirely reset, reprinted and recopy- 



righted January, 1918. Revised, entirely reset, reprinted and 



recopyrighted July, 1920. 



Copyright, 1920, by W. B. Saunders Company 



PRINTED IN AMERICA 



