Earlier Maturation in Man
Over the past 100 years people have been not only getting bigger but also getting bigger earlier. By the same token there has been a dramatic decline in the age of puberty
Features
The Beneficiation of Iron Ores
As North America's high-grade iron deposits approach exhaustion steel production increases. The apparent paradox is due largely to the development of ingenious ways to enrich lower-grade ores...
How Proteins Start
The chain of amino acid units that constitutes a protein molecule begins to grow when a variant of one of the standard amino acids is delivered to the site of synthesis by a specific transfer agent...
Remote Sensing of Natural Resources
Several devices are now available to supplement the aerial camera in detecting natural resources from airplanes and spacecraft. They include radar, gamma ray detectors and sensors of infrared energy...
The g Factor of the Electron
It is the index of the ratio of the electron's magnetic moment to its spin angular momentum. An interesting number in its own right, its precise measurement has had far-reaching implications...
The Venous System
The veins constitute a reservoir for the blood supply, not merely a system of passive conduits. They constrict and dilate actively, thus maintaining a satisfactory distribution of blood in the body...
The Circulation of the Sun's Atmosphere
A new hypothesis may explain how the sun can rotate faster at its equator than it does elsewhere. Analysis of sunspot movements has provided a clue to this 100-year-old mystery
Perpetual Motion Machines
Over the past 400 years numerous inventors have proposed marvelous ways of getting something for nothing. All these proposals have foundered on either the first or the second law of thermodynamics...
Departments
50 and 100 Years Ago: January 1968
Science and the Citizen: January 1968
- Letters
Letters to the Editors, January 1968
- Recommended
Books
- Mathematical Recreation
Mathematical Games
- Amateur Scientist
The Amateur Scientist
- Departments
The Authors
Bibliography
