Scientific American Magazine

Economic development means entry into the high-consumption world middle class. In view of the limits that are set by world resources, only new scientific and technical knowledge can accelerate the rate of entry

Two billion years ago in west Africa a rich deposit of uranium ore began operating as a nuclear reactor. Long dormant but preserved intact, the reactor came to light during the mining of the deposit

Steroid hormones secreted by the gonads and the adrenal cortex can be traced to target cells in the brain. In the newborn animal the sex hormones help to lay down brain circuits that control later behavior

Methods of making steel without smelting ore in a blast furnace are becoming increasingly economic where steelmaking facilities of modest scale are needed, notably in the developing countries

The possible configurations they can form are governed by a few elementary rules that have been known for more than a century. A new mathematical model provides a sound basis for those rules

These small marine animals build themselves a gossamer house out of mucus. The house incorporates an elaborate apparatus for filtering food particles out of the seawater

Experiments demonstrate that bees and ants find their way home by the polarization of the light of the sky. The detection system insects have evolved for the purpose is remarkably sophisticated

They did much to open up the interior of the new United States. Although inland waterways still play a major role, the original canal boom quickly came to an end with the rise of the railroads