Feature

Shortage of Physicists a National Emergency

Millions of Kilowatt-Hours Saved from Engine Tests

New Machines and Gadgets

Chemically “Toughened” Wool Is Developed

First Glances at New Books

Front Matter

Colchicine Injections Change Chromosomes in Fruit Flies

[Photograph]: For FM

Silver in Place of Tin Recommended for Solder

Assembly Line Method Applied to Sun Bathing

Cancer Institute’s Personnel at Disposal of War Agencies

New Sources of Ultraviolet Several Times More Effective