Feature

Finds Men Better than Women as Blood Donors

Rare Element Gives New Kind of Light

Age of Prehistoric Man Measured by Elephant Teeth

Frequent Revolutions Chief Cause of Poor Health

Weather Cycles Make Possible 25-Year Rainfall Predictions

Weed Seed “Horn” Brings Death to Baby Trout

Moonlight as Well as Sunlight Spoils Radio Reception

Carbonic Acid in Air Keeps Earth Warm

Yellowstone Geyser Water Would Make Only Small River

May Skies Herald Approaching Summer

In Science Fields

Movies of Sunset on Moon Are Shown before Scientists