Scientific American Magazine

Great Britain, which developed the imperial system of weights and measures, is now well into a period of transition to the metric system. Before long the U.S. will be the only major nonmetric nation

Within our galaxy are some 200 globular clusters, each consisting of 100,000 to a million stars. The study of models indicates they began life 10 to 15 billion years ago when the universe was young

The cause of this disease of the central nervous system is unknown. The variations in its incidence around the world, however, suggest that it results from infection by a virus with a long latent period

Can memory and learning be studied at the level of nerve cells and their interconnections? A beginning is made by relating changes In the activity of nerve cells to the modification of simple behaviors

In most fluid systems differences in velocity are obliterated by positive viscosity. In some rotating systems, however, nonuniform flows can be maintained by negative viscous effects due to eddies

Most species of Drosophila have overlapping ranges, yet hybrid fruit flies are rare. One reason is that in courtship the females respond to a unique signal that is emitted only by males of the same species

This new planning method can be applied to power grids, computer networks, gas pipelines and other flow-handling systems in order to increase their effectiveness and reliability and reduce costs

Population growth is beginning to slow down in villages of the Punjab. The analysis of such variables in the process as education, health care and economic status may influence India's family-planning program