viii PREFACE 



the point of view which he himself takes in the particular 

 exercise. 



It remains to the writer to thank his colleagues in the 

 University of California for their valuable aid in the prepara- 

 tion of this guide, and especially to Willis L. Jepson, who 

 has made valuable suggestions at every point. 



UNIVERSITY OF CALIFORNIA, 



BERKELEY, CAL., Sept. i, 1896. 



