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Features

Attitudes toward Racial Integration

The third in a series of reports spanning nearly three decades shows a continuing advance in the support of desegregation by U.S. whites. The trend has not been affected by the racial strife of recent years

By Andrew M. Greeley and Paul B. Sheatsley

The Gum Nebula

This enormous cloud of ionized hydrogen is the largest known nebula in our galaxy. Its full extent and nature are currently the subject of considerable controversy among astrophysicists

By Stephen P. Maran

Cryptobiosis

The term refers to the deathlike state of certain primitive animals that have been almost completely dehydrated. When the animals are moistened, even after decades, they revive.

By John H. Crowe and Alan F. Cooper Jr.

Catalysis

Substances that accelerate chemical reactions without being used up play a major role in producing goods worth more than $100 billion a year. Various techniques help to reveal how a catalyst functions

By Vladimir Haensel and Robert L. Burwell Jr.

Multistability in Perception

Some kinds of pictures and geometric forms spontaneously shift in their principal aspect when they are looked at steadily. The reason probably lies in the physical organization of the perceptual system

By Fred Attneave

How Birds Breathe

The avian respiratory system is different from the mammalian one. The lungs do not simply take air in and then expel it; the air also flows through a series of large sacs and even hollow bones

By Knut Schmidt-Nielsen

The Rotation of the Earth

An analysis of recent measurements indicates that one of the main nonuniformities of the earth's rotation-its tendency to wobble gently about its rotation axis-may be excited by major earthquakes

By D. E. Smylie and L. Mansinha

The Talking Drums of Africa

In spite of an abundance of tall tales, drum talk is a reality. Moreover, the drummers of Africa may well have been the first to utilize the principle of redundancy in their communications

By John F. Carrington

Departments

  • 50 and 100 Years Ago: December 1971

  • Science and the Citizen: December 1971

  • Letters

    Letters to the Editors, December 1971

  • Recommended

    Books

  • Mathematical Recreation

    Mathematical Games

  • Amateur Scientist

    The Amateur Scientist

  • Departments

    The Authors

  • Annual Index

  • Bibliography

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December 1971

See the World from a Different Perspective

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