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Food Additives

Perhaps as many as 2,500 substances are currently being added to foods for flavoring, coloring, preservation and other purposes. How are the necessity and safety of these substances determined?

By G. O. Kermode

Nonvisual Light Reception

In the brains of some vertebrates are unidentified organs that respond to daylight. Experiments with blinded birds demonstrate that these organs control biological rhythms

By Michael Menaker

Geosynclines, Mountains and Continent-Building

A geosyncline is a huge deposit of sedimentary rock that forms at the edge of a continent. When it is compressed, it buckles up into a mountain range. It also enables a continent to grow by accretion

By Robert S. Dietz

Electrostatics

The field around a charged body is used to manipulate particles of matter. Among the modern applications of electrostatics are fly-ash precipitators, paint sprayers and Xerox copying machines

By A. D. Moore

Do Infants Think?

They supposedly know the world only in terms of sensory impressions and motor activities. New experiments suggest that their cognitive, or hypothesis-forming, development begins at the age of nine months

By Jerome Kagan

The Sources of Muscular Energy

The immediate source is adenosine triphosphate (ATP). The ultimate sources are the combustion of food and the breakdown of glycogen. The time relations of these processes offer some practical hints

By Rodolfo Margaria

How did Kepler Discover his First Two Laws?

It is generally assumed that he did so by calculating the distances between a planet and the sun and then perceiving that the distances fitted into an ellipse. It is more likely that the ellipse came first

By Curtis Wilson

Departments

  • Letters to the Editors, March 1972

  • 50 and 100 Years Ago: March 1972

  • Science and the Citizen: March 1972

  • The Cave Bear

  • Recommended

    Books

  • Mathematical Recreation

    Mathematical Games

  • Amateur Scientist

    The Amateur Scientist

  • Departments

    The Authors

  • Bibliography

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March 1972

See the World from a Different Perspective

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