Scientific American Magazine

The U.S. has at its disposal ample "national technical means" of surveillance to detect any attempt by the U.S.S.R. to gain a significant military advantage by violating a new arms pact

Bird embryos take up oxygen and discharge carbon dioxide by simple diffusion through microscopic pores in the eggshell. The process is regulated largely by pore geometry, which varies among bird species

Mountain lakes from France to Austria and from Germany to Italy attracted many prehistoric settlers. Underwater archaeologists are now investigating sites that once were only dredged by collectors

The management of a forest by such techniques as the selective harvesting of trees, prudent thinning and planned reforestation can double and perhaps even triple the productivity of the forest

They are waves that do not disperse or dissipate but instead maintain their size and shape indefinitely. A recent finding is that solitons may appear as massive elementary particles

The source is believed to be a dynamo set up by the ponderous flow of matter in the earth's core, but what drives the flow? It may be the gravitational energy released by the sinking of heavy material

In sexual reproduction the parental genes are continually reshuffled and thereby exposed equally to the stringent test of natural selection. Some genes cheat, subverting the process to favor their own survival

The first instrument generally used for diagnosis, the stethoscope transformed the practice of medicine in the 19th century, altering the physician's picture of disease and his relation to the patient