Feature

[Photograph]: Diatoms Test Lens Quality

Low Cost “Atom Sifter” Sorts Atoms by Their Weight

[Photograph]: Detect Radioactivity

Erratum: Meningotoxoid a Possible Weapon against Meningitis

Erratum: Hay Fever Time

Erratum: Rumania Has Grain, Wood, Richest Oil Fields in Europe

Erratum: In Science Fields: Vitamin B₂ Used on Rats as Weapon Against Cooties

Erratum: Nobel Physics Prize Honors Machine as Well as Its Maker

First Glances at New Books

Health Gains of 1939 Will Be Carried Onward in 1940

[Photograph]: Balloon Shows Behavior of Star

New Chemical Stops Growth of Pus-Forming Staphylococci