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Underground Reservoirs to Control the Water Cycle

At any one time perhaps two-thirds of the fresh water on the earth is held in underground reservoirs. These reservoirs could be much more intensively drawn on, to be refilled when water is plentiful...

By Robert P. Ambroggi


This extinct primate is the earliest hominid, or distinctively manlike, member of man's family tree. The finding of many new specimens of it has clarified its place in human evolution

By Elwyn L. Simons

Amorphous-Semiconductor Devices

Glassy materials that act as electronic switches rival crystalline materials for certain tasks. Their electrical behavior is now better understood, opening the way to a wide range of new applications...

By David Adler

Cancer Immunology

Cancer cells have "foreign" labels, yet they can escape destruction by the immune system. Efforts are being made to learn how they do so and to utilize the immune response for treatment of the disease...

By Lloyd J. Old

The Case of the Missing Sunspots

Old records indicate that between 1645 and 1715 there were virtually no spots on the sun. It seems likely that the activity of the sun varies considerably, and that the present period is an unusually active one...

By John A. Eddy

Exploring the Herbarium

Valuable information on little-known plants that might provide new foods or drugs can be gathered by examining labels attached to the millions of specimens in the world's botanical collections...

By Siri von Reis Altschul

Rat Societies

Norway rats survive in a hostile human environment by means of complex social mechanisms that ensure communal peace, equal opportunity between the sexes and early learning of vital information about the environment...

By Kevin Flannelly and Richard Lore

Stein's Paradox in Statistics

The best guess about the future is usually obtained by computing the average of past events. Stein's paradox defines circumstances in which there are estimators better than the arithmetic average...

By Bradley Efron and Carl Morris


  • 50 and 100 Years Ago, May 1977

  • Science and the Citizen, May 1977

  • Letters

    Letters to the Editors, May 1977

  • Recommended

    Books, May 1977

  • Mathematical Recreation

    Mathematical Games, May 1977

  • Departments

    The Authors, May 1977

  • Bibliography, May 1977

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