50, 100 and 150 Years Ago; December 2000; Scientific American Magazine; by Staff Editor; 1 Page(s)

COLOR TELEVISION-"The Federal Communications Commission has finally adopted the color-television system advanced by the Columbia Broadcasting System. The 'field-sequential' system has color filters mounted in a rotating wheel in front of the cameras, which separate the image into its three primary colors. At the receiving end images are reproduced on a screen of a single tube and are translated back into color by another filter wheel synchronized with the camera wheel. The CBS image cannot be received in black-and-white on the estimated eight million existing TV sets unless they are equipped with an 'adapter.'" [Editors' note: Lack of public interest in this system halted color broadcast within a few months.]

THE HAZARDOUS STRATOSPHERE-"When intercontinental flight through the stratosphere becomes a reality, the hazard of cosmic radiation must be considered, the intensity of which increases with altitude. Hermann J. Schaefer of the U.S. Naval School of Aviation Medicine in Pensacola, Fla., estimates cosmic radiation at 70,000 feet as 15 milliroentgens per day, in excess of the radiation safety standard set by the Atomic Energy Commission. Such doses will not cause appreciable physiological damage. 'But,' says Schaefer, 'the prospect that future commercial air traffic will be at those altitudes and an increasing percentage of the population will be exposed to those dosages is bad from a genetic viewpoint.'"