Youth Unemployment
Getting work has been increasingly difficult for young Americans ever since the 1950's. Among nonwhites more than a third of the teenagers and a fifth of the young adults are currently unemployed
Volume 242, Issue 5
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Features
The Superconducting Computer
A new microelectronic technology would replace transistors with superconducting switches. Computers made with them might carry out a billion elementary operations per second
The Role of Gravity in Quantum Theory
An experiment with a neutron interferometer, an instrument in which neutron waves interfere, has shown that the laws of quantum theory apply in the presence of gravitational fields
Myelin
It wraps around nerve fibers and gives them electrical insulation. Its presence reconciles the brain's conflicting needs for compact size, complex circuitry, rapid signaling and modest use of energy
The Chemical Evolution of the Earth's Mantle
Clues to the nature and timing of the mantle's differentiation are gained from precise measurements of the isotopic ratios of certain trace elements in rock samples from continental and oceanic crust
The Kinematics of Plant Growth
Like a flame or the wake of a boat, the form of a plant changes slowly but the components are in continual flux. The motions of the components can therefore be analyzed in terms of fluid flow
The Origins of Copper Mining in Europe
The age of metals began with the use of "native" copper in the Old World. As rising demand required the mining of copper ores one of the first mines in Europe was opened at Rudna Clava in Yugoslavia
The N-Ray Affair
Early in this century an eminent physicist discovered a new kind of radiation, and others confirmed his work. The radiation turned out to be totally imaginary, proving that believing can be seeing