ACKNOWLEDGMENT 



As in every work of this sort, the real source of inspira- 

 tion, of guidance and of criticism lies in the Instructors of 

 the Department in which the work was done. In this par- 

 ticular case, the author wishes to acknowledge his indebted- 

 ness and gratitude to Professor Angell and Dr. Carr. Their 

 helpfulness has extended far beyond the immediate assist- 

 ance given in this thesis. No one can be under their tute- 

 lage without being influenced for the better by their ideals 

 and practice. In particular, Dr. Carr's constant and 

 patient oversight and criticism was a large element in 

 carrying this present work to a successful issue. 



Acknowledgment is also due to Mrs. Wylie for assist- 

 ance in performing the experiments and in preparation 

 of the manuscript, 



Harry H. Wylie 



