TELEVISION PREMIERE

Evening Star, Issue 22448, 19 September 1936, Page 4

TELEVISION PREMIERE

VOICE AND SIGHT PROGRAMME Television broadcasting had its New York premiere recently when the Radio Corporation presented, from an experimental station in the Empire State building, a “voice and sight” programme. The demonstration, staged under ideal atmospheric conditions, included introductory statements by officers of the corporation, an ensemble of dancing girls, the streamlined train “ Mercury,” a fashion parade, a comedian, and a radio announcer, thus showing the application of television in a wide range of subjects. The images, Sin by 7in. were viewed in a darkened room, the consensus of opinion being that until the size and clarity of the pictures are improved, such broadcasts would be received only as a novelty. The 10 kilowatt transmitter appears to have a range of close to 90 miles, but the R.C.A. has declared that there is no intention of marketing receivers during 1936. COST OF LIGHTNING UNCANNY PRESENCE OF ATMOSPHERICS Under present electric power charges it would probably cost something like £ls to buy an average lightning flash. This is according to the calculation of Dr Wallace A. Macky, M.Sc., of Wellington, who, in the Auckland University College Hall, spoke of the fascinating and, to the layman at least, uncanny presence of electricity in the atmosphere (reports a local paper). “In an average storm,” said Dr Macky, “ there can easily be a flash every ten seconds, and such a storm wastes energy at a rate of over 2.000. horse-power. When we consider that there are at any given instant some 1,800 thunderstorms over the earth, we arrive at the huge figure of 3,600,000,000 horse-power, or 2.600.000. as the power being continually wasted in these storms. It is interesting to compare this power with the lOkw of the new IYA; no wonder static often gets the better of a radio station.” There was a current of electricity continually flowing into the earth from the air in fine weather, said Dr Macky, and its value was found to be close

to 1,000 amps, for the entire surface of the globe. The major problem of atmospheric electricity was: Where did all this current come from? It was a problem by no means entirely solved. Measurements of this fine-weather potential gradient,” as it is known, had been made for several years, and it had been found not at all constant at any given place. There was a yearly and daily variation, and over the land there was an early-morning maximum resulting from the smoke of fires being lit as the day’s work began. The interesting thing about the daily variation was that it kept in step with the number of thunderstorms taking place on the globe. There were definite indications that the thunderstorms were connected with this current which flowed into the earth. A lightning flash, Dr Macky went on, was merely a very large scale electric spark: Benjamin Franklin had proved the identity by actually getting sparks from a wire attached to a kite which ho flew underneath a thunderstorm. “ I imagine that ho was very lucky to survive to tell the story,” added the speaker. “ Since the advent of broadcasting we are much more used to hearing lightning than seeing it, for the static winch we hear is nothing more than the electric impulses sent out by lightning flashes, sometimes near at hand and sometimes far away —and the further away the better, from the point of view of our wireless reception.”