RADIO ATMOSPHERICS

Timaru Herald, Volume CXXXVIII, Issue 19958, 16 November 1934, Page 3

RADIO ATMOSPHERICS

RECENT RESEARCH WORK Atmospherics play noisy games on the wireless. The listeners often wish they could be told that good atmos- t pherics should be seen and not heard. Their shrieks and whistles are only too often heard, yet few wireless listeners have ever expected to see one. Professor Appleton and Mr Watson Watt have done more than see atmospherics. They have photographed them, tail and all, and tell us now how an atmospheric begins, how it grows, what it is like, and just what it does. They present the life-%tory of an atmospheric. An atmospheric may be bom in a lightning flash at Teddington, where the camera of the National Physical Laboratory is turned on it, and reach out to a wireless receiver 3000 miles away about a thousandth of a second afterwards. It is born with a head, according to the photographs, and develops a tail. The head arrives at the wireless receiver first, bringing its tail behind it, and the tail may be 500 miles long. The sting of the atmospheric is in its head, instead of its tail, though the tail makes more noise. The head vibrates in such a way as to pierce most wireless receivers. The tail has a vibration, or, in another phrase, a wavelength, which like a sound wave can make itself heard by the human ear. It certainly does so, and sometimes the length of the waves is such as to produce a sound like a whistle. This sound, which all wireless listeners know, is something like the whistle of a passing train, dropping in pitch as the train goes by. It does not interfere with the receiving instruments so much as the more disturbing head waves. The tail grows because the shorter wavelengths appear to move faster than the longer ones, though wireless science cannot tell why they should. When more is known about the atmospheric’s tail, why it wears it and how it lengthens, the scientific men may be unable to stop its growth, or prevent the disturbance it causes, but they will be better able to track it down to its place of origin. When that is done they may be able to say what kind of condition of the air favours its passage most, and so will have better information on which to forecast the weather.

The atmospheric, now that its photograph is at the disposal of the Scotland Yard of science at Teddington, and the National Physical Labora-