Feature

DDT More Dangerous, Fat Accumulation Hints

Complete White-Negro Mixing in 1,000 Years

Porpoises May Have Their Own Sonar Device

Snails and Tortoise Not Lazy but Muscles Slow

Lens Snaps Clearer Photos High in the Air

Colleges Can Handle GI’s

Helium Burned to Carbon for Older Stars’ Energy

Reversible Baldness

[Photograph]: Ripple Tank

Front Matter

Over 400 Astronomers See Vatican Observatory

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