Detecting Icebergs by Radio

Radio Record, Volume III, Issue 35, 14 March 1930, Page 3

Detecting Icebergs by Radio

Poressor BARNES, an American scientist, has recently invented an apparatus which should effectively remove one of the greatest dangers associated with ocean travel, namely, the possibility of collision with icebergs. It ha., been discovered that an iceberg is ten per cent. air-air that is thousands of years old, and which was trapped with the snow that fell on the high ‘icecaps at the North and South Poles. When the iceberg begins to melt in warmer currents, the.air comes. to the t rface with a hissing sound. plainly ‘ible at a considerable distance. x nen there are no ship noises to drown it ‘out. Professor Barnes hoped that a highfrequency microphone, connected to u sensitive radio-amplifier, would be able to pick up the hiss from under the sea. The initial tests were disappointing, however, for no sound could be heard. A low-pitched microphone, which had been taken with the expedition accidentally, when pressed into commission. developed a loud noise, and it was discovered the source was the constant melting and cracking of the berg below the waterline. At a six-mile range it was found the noise of the melting berg could be clearly separated from all sounds on the ship. _j Can you solve a difficult problem? X . See "TRIALS IN TACT" (On page 27 of this issue.)