12 FEBRUARY 1921, Page 24

The Scientific Papers of Bertram Hopkinson. Collected by Sir J.

Alfred Ewing and Sir Joseph Larmor. (Cambridge University Press. 63s. net.)—The late Professor Hopkinson was killed in August, 1918, when he was serving with the Royal Air Force, for which he had done much experimental work of great value. His friends have prepared this volume as a memorial of the distinguished physicist. It contains a number of papers, principally concerned with iron and steel, and with gas and petrol engines. Sir Alfred Ewing has prefixed a memoir, and Mr. A. V. Hill writes on Professor Hopkinson's work in the Air Force. His death at the age of forty-five was one of the most grievous losses which British science sustained in the war.