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Orthodox and Unorthodox Methods of Meeting World Food Needs

The orthodox methods must be pressed, but it seems they cannot solve the problem without the aid of the unorthodox ones. And the adoption of unorthodox methods calls for basic changes in cultural attitudes...

By N. W. Pirie

The Repair of DNA

The two-strand molecule that incorporates the genetic information of the living cell is subject to damage. Experiments with bacteria reveal that the cell has a remarkable ability to repair such damage...

By Robert H. Haynes and Philip C. Hanawalt

Reversals of the Earth's Magnetic Field

Some volcanic rocks are magnetized in a direction opposite to that of the present magnetic field of the earth. The reason is that the earth's field has reversed nine times in the past 3.6 million years...

By Allan Cox, Richard R. Doell and G. Brent Dalrymple

The States of Sleep

Light and deep sleep differ physiologically, deep sleep having much in common with being awake. Studies with cats now suggest that the two states of sleep are induced by different biochemical secretions...

By Michel Jouvet

The Solvated Electron

It is an electron that is released into solution when certain metals are dissolved in a liquid such as ammonia. It can also be released by ionizing radiation, and it may play a role in many chemical reactions...

By James L. Dye

Controlled Eutectics

A combination of metals with a particularly low melting point is called a eutectic. By controlling the way a eutectic solidifies It is possible to produce alloys with a host of useful properties...

By R. Wayne Kraft

Medical Thermography

Measurement of the heat emitted through the skin at various points on the body has proved valuable In the diagnosis of such disorders as tumors and arthritis and In observing the effects of treatment...

By Jacob Gershon-Cohen

Living Prehistory in India

In India, as in many other lands, herdsman has succeeded hunter and farmer has succeeded both. A study of tribal groups that still pursue these ancient livelihoods helps to illuminate a shadowy past...

By D. D. Kosambi


  • 50 and 100 Years Ago: February 1967

  • Science and the Citizen: February 1967

  • Letters

    Letters to the Editors, February 1967

  • Recommended


  • Bibliography

  • Mathematical Recreation

    Mathematical Games

  • Amateur Scientist

    The Amateur Scientist

  • Departments

    The Authors

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