SCIENCE SIFTINGS

New Zealand Tablet, 8 September 1921, Page 46

SCIENCE SIFTINGS

======== By" VOLT” =========

EIGHT PHOTOS SENT 3000 MILES BY WIRE. A Dempsey-Carpentier picture, taken at - 3.30 on the afternoon of July 2, was published in the Los Angeles Times on the morning of July 3. The photograph was transmitted some 3300 miles in a little over three hours, and came out very little the worse for wear after its’long, fast journey. No airplane, of course, could approach this speed, even though, as the Times informs us, the paper broke all records in bringing photographs of the fight across the continent by air. That method took 47 hours, 50 minutes, a rate of speed. astonishing enough in itself. The “revolutionary device” used in the practically instantaneous transmission of the photograph, called by the Times “telephotography,” consists of a novel use of code numbers, so combined with a diagrammatic background that the original photograph may be produced, at any distance, almost as fast as the code can be sent forward by telegraph, long-distance telephone, or wireless. The method, said to bo extremely simple, is declared by the Times to be capable of great refinement over the first results. But even these pictures, we are told, are “incontestable proof that pictures can be sent by telegraph as readily as can ordinary English.” In view of the fact that “sending photographs by wire has been an unrealized ambition of every newspaper in the world for over 30 years, the importance of this achievement is apparent,” says the Times writer.. The method, as developed by the Los Angeles paper, began with the taking of special photographs at the ringside in Jersey City. They were rushed by automobile and motor-boat to the office of the Daily News in New York City, where the plates were developed. Then the business of putting the picture on the wire really began. The explanation of this process runs: “As soon as prints were sufficiently dry they were placed under specially prepared transparent sheets of celluloid on which numbered perpendicular and horizontal lines I of an inch apart had been drawn. These sheets were prepared in the Times office in Los Angeles and were mailed to New York several days before the fight. A detailed tracing of each photograph was made by the Times artist in New York, each contact of the traced lines across the quarter-inch squares furnishing a unit number destined for the telegraphic code. Where curves or small inequalities occurred in the tracing fractional numbers J were used. The complete' code, -consisting of more than 400 separate number combinations, was ivired to the Times Washington office and thence relayed over the Times’s leased wire direct to Los Angeles. The actual time of transmitting the picture by telegraph was 50 minutes, while an hour and 10 minutes were consumed in' decoding. The insertion of the blacks and whites, supplied by telegraph, took a little less than another hour. A duplicate of the celluloid sheets used to code the picture in New York was used in the Times office in Los Angeles for translating the numbers into a line drawing which, in turn, became a faithful reproduction of the original photograph by the addition of the lights and shadows described by wire. The code numbers which produced the Dempsey portion of the picture are thus explained; — By it the picture may be drawn on such a screen as used by the Times. The screen may be made by ruling a sheet of paper with lines forming exact squares one-quarter inch each way. Beginning at the bottom, number the horizontal lines 1 to 62 inclusive. Beginning at the uppper left-Jiand corner, number the vertical lines 63 to 110, inclusive. Each pair of numbers marks a point on this screen; these points, connected, make the picture in outline.