24 MARCH 1923, Page 16

Crystallisation of Metals. By Colonel N. T. Belaiew, C.B. (University

of London Press. 7s. 6d. net.) Crystallisation of Metals. By Colonel N. T. Belaiew, C.B. (University of London Press. 7s. 6d. net.) This book contains four lectures deWered in 1922 by a dis- tinguished Russian metallurgist at the Royal School of Mines. The subject is a somewhat recondite one, and the general reader can hardly be expected to take an intelligent interest in the " spherodisation of cementite in hypereutectoid steels." Yet the structure of old Indian sword blades—the famous Damascene steel—turns out to be nothing but perfectly spherodised cementite. Colonel Belaiew was the first to reproduce synthetically the Widmanstatten figures charac- teristic of meteoric irons. His lectures are invaluable for specialists.