Exploring that region of radio waves so short that they approach the invisible heat and infrared rays, engineers of the General Electric Company have discovered interesting and unexpected phenomena.
An experimental 5-meter radio sending set was recently put into operation at South Schenectady where the experimental radio work of the company is done. Previous tests with sending stations on 15 to 30 meters, wavelengths far below those usually used in broadcasting, had caused the engineers to expect somewhat unusual results, such as complete fading close to the station and extremely satisfactory reception at extreme distances.
But in the preliminary tests with the 5-meter set, it was found that radio signals of that high frequency had a shadow effect very much like light. A small hill prevented reception in the valley beyond.
An additional danger of typhoid infection from oysters has been brought to light by Dr. William H. Park, director of the bureau of laboratories of the New York City Department of Health. He reports that the liquid in which shucked oysters are carried provides an excellent breeding ground for the typhoid bacillus. Bacilli from an infected oyster therefore not only may be carried by the liquid to other oysters but also may increase during their sojourn in the liquid.
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| Diphtheria immunization puts tots on the honor roll. This scene was taken at a Milbank Memorial Fund health demonstration in Syracuse, N.Y. |
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