SEEING THROUGH FOG.

New Zealand Herald, Volume LXVI, Issue 20365, 20 September 1929, Page 14

SEEING THROUGH FOG.

IMPORTANT INVENTION.

AID TO NAVIGATION

[from Ot'B OWN CORRESPONDENT.]

LONDON, Aub. 15

The "Noctovisor," an apparatus which, it is claimed, will enable the lights of a 3hip half a mile away to bo soen in tho densest fog, was demonstrated at a little chalet on Box Hill on Sunday by . Mr. John L. Baird, the invontor of television. The machine, mounted on a turntable, was directed toward the Surrey valley, where' tho headlight of a car moving along tho road two and a-half miles away could easily be seen. . At. a flashed signal.from ono of the watchors on the hill,' tho car light was shut off from ordinary view by a sheet of ebonite which, for the purpose of the experiment, was "fog." Gradually, as tho "Noctovisor was moved round, an imago of tho vanished light crept across a screen inside, its exact bearings being registered on . a graduated scalo, on tho turntablo. ■ It was explained that, while a lighthouse or a car-lamp behind an ebonite screen could, thus bo mnde visible two and a-half miles away, an ordinary Bhip's light would be detected within half, a mile, though a radiu3 of two miles at least was expected' to be achieved shortly. In its present form the new invention is able to register only the invisible infrared rays emanating from a direct sourco of light at theso distances.' The principle on which it is constructed is that of a combinod televisor and receive**. It reproduces the infra-red ■ rays as an orange Mr. Baird says that several naval and mercantile officers have seen the "Noctovisor," and believe it will be of enormous use to ships at soa. "It should be of great use" to fog-bound ships," he says. "A ship in oven tho thickest fog will be able to seo.the lights of ships near by." It is hoped that tho "Noctovisor" may soon bo placed on every British liner, and it is pointed-out that in naval warfare a battleship so equipped would possess eyes that the enemy would lack.