PREFACE IX 



U. S. G. Kuhn III, G. W. Leddicotte, W. E. Lotz, R. A. Monroe, G. W. 

 Morgan, R. T. Overman, J. H. Rust, C. W. Shcppard, N. E. Tolbert, 

 B. F. Trum, W. J. Visek, H. Wiebe, L. P. Zill, and D. B. Zilversmit. 

 Especial thanks are due to I. B. Whitney for permission to use unpublished 

 data and for assistance with Chap. 6. Numerous individuals and organi- 

 zations, whose names may be noted in the references, have been most 

 gracious in granting permission to quote published material. I am deeply 

 indebted to Mary Alice Carneal for secretarial help. 



C. L. COMAR 



