CONTENTS 
Page 
Mathematics. — On the Representation of a Number as the Sum of any Number 
of Squares, and in Particular of five or seven . . . . By G, H. Hardy 189 
Physics.'— The Crystal Structure of Ice By Ancel St. John 193 
Geology. — Fringing Reefs of the Philippine Islands . . . ByW.M. Davis 197 
Pathology. — Dilation of the Great Arteries Distal to Partially ^Occluding 
Bands By William S. H aisled * 204 
Physics. — On the Correction of Optical Surfaces . . . . By A. A. Michelson 210 
