SOUNDINGS BY ECHO

Evening Star, Issue 19723, 25 November 1927, Page 2

SOUNDINGS BY ECHO

The echo method of sounding is rapidly proving itself more efficients than tho former method of sounding by wire. The report of recent ex-; periments, published in the ‘ Forschungcn nnd Fortscliritte/ states that, on a German sounding expedition, out of nearly GB,OOO soundings made, over 67,300 wore made by echo and only 433 by the sounding wire. The importance of the improvement brought about by tho echo method lies mainly in its time-saving advantages. To make a single wire sounding at a depth of 5,000 metros it is stated that a cable vessel requires something like an hour. Echo sounding is also claimed lo be 1 more reliable, in that on some occasions the w’ire fails to touch ground, and its recordings may be inaccurate owing to tho difficulty of sinking a wire iu an exactly perpendicular direction. In tbo new system the sound is made on board tho vessel. To enable it to be beard distinctly, a high note is struck, of 1,050 vibrations, _ approximately tiie high C of a piano, the echo is picked up by means of a microphone, which sols up a current in a telephone receiver.