396 
SYMPOSIUM PHOTO INTERPRETATION, DELFT 1962 
Acknowledgments 
The author is particularly indebted to Dr. D. Q. Wark, U.S. Weather 
Bureau, for his review and criticisms of this paper, to Lt. W. A. Dotson of 
the U.S. Navy Hydrographic Office for his assistance and advice concerning 
the interpretation of ice observations, and to Major C. I. Taggart and the 
staff of the Joint Photographic Intelligence Centre, R.C.A.F. Station Rock- 
cliff, Ontario, for furnishing the mosaic of CF-100 aerial ice photographs.