DAYLIGHT GLASSES

Dominion, Volume 7, Issue 2245, 3 September 1914, Page 8

DAYLIGHT GLASSES

i-SFECTACLES TO TRANSFORM ARTIV ..-:.FI0IAI LIGHT. ■■~....

So much work is being carried on with a view to producing artificial light resembling daylight that a new suggestion made by the well-known physicist, .Mr. H. E. Ives, of.employing "daylight spectacles" 'has', aroused much interest. Mr. Ives ! has been for some time investigating '■ the - production of light giving a diiylight- spectrum, and bas calculated recently the actual cost cf illuminating a room with artificial light- of-the'same intensity and colour asvordihary..daylight.-'Screens are already.'', employed Viir. certain industries, Which , are placed'in front of incandescent' gas or 'electric lamps,. tho Htered rays' being practically equivalent to daylight.'-.' A great' , proportion of the light is-lost-so that such:methods are very ineffieieut. /'The..'advantage, 'however, in" work such as colour printing and fabric dyeing-js : fully, recognised. ■ Mr. Ivei's ;sugn;estipn of using colour-e-l glass spectftcles, wliich would screen off tho unwanted; rays so that the eye would appear,to see only daylight, opeiis up many interesting possibilities, though there would have fto be one sort ( of glasses for each different typo of illumlnaiit. The loan of such spectacles to visitors to picture, galjeries would enable'them to see tho.piotures under favourable conditions at night-time, and it would also enabfe those engaged in industrial work where colour matching is important to work in artificial light in dull weailier and at night. In certain work, notably the .making-of artificial teeth, where colour has to be most delicately matched, work is actually susponcled.in dark or foggy weather] , only daylight being suitable for the matcliing of the tints. The same'thing also applies'in certain cases to .the choosing of colours slid their matching and mixing in wall-paper' printing and similar trades. The light filters usually employed are prepared with glass covered with a collodion or Rcbtino furface, vhich is stained- with earef;llly selected aniline dyes. 'A'further difficulty would arise in the making spectacles' if pot fired glass were employed, as it is not easy to control the colour,-but some interesting experiments are being carried out in this direction.