12,000,000 CANDLE-POWER

Dominion, Volume 14, Issue 60, 4 December 1920, Page 9

12,000,000 CANDLE-POWER

THE "INCANDESCENT SEARCHLIGHT. Delegates to tho International Coraraunications Conference, were greatly astonished while paying a visit to' the works of the General Electric Company in. Aew York-by Vein# shotfn m operaton an incandescent lamp searchlight of 7,000,000 candle-power. That. marvel is one. of the. results of the experimental resaarch. work carried o\\t during tho J* ar » v® 1 ?"- so; remarkably successful havo the- illuminating engineers been who have forked at' this problem that the incandescent searchlight that can operate on either an alternating or. **liroct curlemf c . ircuit !s now accomplished fact. The: first ■ use of the; incandescent searchlight on a large scale- took place fu, few months ago during a carnival at baratoga Springs, when at night-. Hie Wfrffie skv was suddenly Tit up bv abnttery - of searchlights, the powerful- beams of which originated in incandescent lamp's says the London "Observer." The ntw searchlight. is also fast displacing arc 'searchlights for many, practical purposes, ■such-ns coastwise .steamers and operations which have to be carried out nt night. It is now nossible by means of a 12-volt lamp of 100 amperes to-develop 12.000,000 candle-nower, and by the employment of special lenses, which utilise light rays wasted in-the parabolic form of .lens., tjie candle-power of a lamp can be. doubled without,any..increase in tho electrical power.

A writer in the "Scientific American" recently predicted that it will soon be possible to attach -a searchlight to! the ordinary lighting circuit of a house, and !>v.its means' throw a beam" so brilliant that by' its aid small print-could be read quite easily' a. mile away, from the foiirce. :Experimentallv, this'has' already beena'chieved, W*t certain orotectivo devicel? will be necessary before-it would he safe to '"nstall ono of these incandescent rearchlights in one's house'..

A light of one candln-pon'nr. it may be added, isthe ermivalent of the liirht of a candle burning 120 grains of snerin in one hour, .one metre from the observer. Si>". of . snrh candles go to Hie pound. Extraordinarily powerful lights Tihvo of late Years been installed in .lighthouses, tlint at St. Catharine's Point, in. th« Tsle, of Wight, being of .15 nflfl.fiOO candle-power. The most powerful- lighthouse light in Tlurone is Hie Heligoland li™ht of .lft.oofl.ooo candlepower. but nn.niw.ono candle-rower is claimed for that in' the Navesihk lighthi,n«e. on t,he roast of N«w .Terser. Tf nil the li'-hts, electric and gas, through(ii'it .London, were concentrated in one place ' the resulting candlo-nower wou'd be one and a nunrler million. or only one-fortieth of .'the candle-power of the tyavesint: liehthouse .light, the 'most powerful in the world..