(3 of 6)
The Sailor's Ears. But in hunting sub merged submarines, sound waves, rather than radar, must be used. Ordinary sound waves do not help, however, because they radiate in all directions, like ripples from a stone dropped in a pool. What is needed is a sound beam that will travel in a straight line and bounce straight back.
Such a beam was found during World War I by a French physicist, Paul Langevin, in the very high frequency range of inaudible impulses: supersonics. But not until World War II was the supersonic detector developed into a reliable instrument.
Not to be confused with the well-known sound detector which picks up a sub marine by the noise of its screws, the supersonic locator uses a beam and its echo, just like radar. It became a practical device when a method of interpreting the supersonic signal was developed. Recently it has helped make submarine-chasing more sure. The first official disclosure of the device was made three weeks ago by Secretary Harold L. Ickes, who reported that the Interior Department planned to make use of it for locating schools of fish.
Though radar and submarine-fighting devices are perhaps OSRD's most valuable contributions, to the men on the fighting fronts OSRD is known for a profusion of more prosaic but vital inventions. The weekly output of its own and allied scientists is amazing. Last week's, for example: a new 500-lb. oil-and-magnesium fire bomb (called "the Goop") which cannot be extinguished; an electronic gadget for regulating air pressure in plane super chargers; two new hard-hitting armored cars (one U.S., one British) which carry cannon and can fight tanks; a safe new bomb fuse with a tiny propeller which unscrews and primes the firing mechanism while the bomb falls; a new putty for filling dents and crevices in plane wings, which, by cutting wind resistance, saves 180 horsepower.
Indicative of science's immense, wide-ranging role in the war are these war-born U.S. inventions:
¶ Torpedoes which steer themselves, can travel five miles at better than 50 m.p.h.
¶ A chemical treatment of wool that makes soldiers' suits mothproof and wash able.
¶ Methods of fireproofing flying suits, clothing, bedding, upholstery.
¶ Recoil-absorbers that make it possible to mount a 75 -mm. cannon in a plane.
¶ Power-operated plane gun turrets and automatic gun sights.
¶ Rockets (and their cousin, jet-propulsion), which have many uses — e.g., as a light arm (the bazooka), in cannon and anti-aircraft guns, for boosting heavy planes off the ground.
¶ Fluorescent and phosphorescent materials which enable soldiers and airmen to see objects at night.
¶ Methods of speeding the production of penicillin.
¶ A revolutionary mosquito bomb, using a rapidly spreading gas (freon) to disperse insecticide, which instantly fills a room or tent, kills all insects within a few minutes, lasts 20 times as long as an ordinary spray.