COPYRIGHT 1*19 BY 

 THE UNIVERSITY or CHICAGO 



All Rights Reserved 



Published May 1919 



Second Impression December 1919 



Third Impression December 1921 



Fourth Impression January 1923 



Fifth Impression October 1923 



Sixth Impression October 1924 



Seventh Impression October 1925 



Composed *md Printed By 



The University of Chicago Press 



Chicazo, Illinois. U.S.A. 



