INFRA-RED MAGIC

Hawke's Bay Tribune, Volume XXIII, Issue 210, 18 August 1933, Page 13

INFRA-RED MAGIC

NEW USES FOB NEW BAYS. GREAT POSSIBILITIES. The use which the British Museum is making of the infra-red process for deciphering early Egyptian texts on leather reminds us of the fascinating new field, with its important results and far-reaching possibilities, which has been opened by this new method to the whole art of photography. For some time we have been familiar with long-distance views taken by the infra-red; and recently in an interview with a representative of "The Observer,” Mr. Olaf Bloch, the well-known chemist and head of the research department of Ilford, Ltd., described other applications of the process which are less well known. He explained, in the first place, how the long-distance views are obtained. The infra-red, he said, has the power of penetrating haze, and thus it is that many miles of landscape can be photographed. Red light is less scattered by particles constituting dust or fog than blue light. What is being done at the British Museum, he said, is to render legible Egyptian texts which were inscribed on leather in 1200 B.C. The leather itself is now so dark as to be almost black, and only faint traces of the inscriptions are visible to the unaided eye. In medical science the process is being used for detecting abnormal conditions just below the surface of the skin. For actual surface effects ordinary photography, Mr. Bloch said, is much better, while X-rays, of course, with their short wavelength and far deeper penetrative power, offer a totally different phenomenon. With the infra-red method Professor Haxthausen, of Copenhagen, has successfully photographed varicose veins beneath the surface of the skin. Astronomical observations of great interest are being made by the new process. Perhaps the most notable, Mr. Bloch recalled, was that of the planet Venus, at Lick Observatory last year. The light we receive from Venus, he

remarked, is sunlight reflected from the atmosphere of the planet. When this light is analysed in the spectroscope bv the infra-red process bands characteristic of carbon dioxide are seen, and as these do not exist in sunlight we are left to speculate on how they occur in the atmosphere of Venus, and whether they are due to vegetation on the planet. New fields for the process are constantly being explored. Ono of the aims is to extend its application to cinematography, perhaps in the presentation of dark scenes in the studio. There is also a possibility here of its use for the detection of crime. A burglar, for instance, passing across a beam of infra-red light, which to him would be invisible, might set in action a photo-electric cell and a silent camera apparatus, which would take an incriminating film of himself and all his actions.