White Magic (1940)

[Music] light is Magic there is Magic in the way it is created in the way it travels the way it behaves and Beyond The Magic of light itself there is the magic of science finding new and amazing uses for light the lifegiver sunlight is a mixture of several different kinds of light most familiar is the visible light the kind of light we see and see by then as modern Sun worshippers know Sunshine contains an invisible form of light called ultraviolet ultraviolet light produces tan skins and those healthy little things called vitamins science has learned how to produce this invisible form of light artificially and now without leaving our homes we can turn winter Into Summer the scientific ultraviolet light generator is arranged to remove all of the visible light and project a strong beam of invisible black magic light one of the most amazing things about ultraviolet light is its ability to help us see things which by ordinary light are impossible to see the radiations of pure ultraviolet light produce a strange effect called fluorescence fluorescence is a glow such as is found in the figures of an illuminated clock dial many different chemicals respond to the radiations of ultraviolet light different chemicals seem to respond with a different glow this fluorescent effect makes it possible to read many secret or hidden messages the ink with which the hidden message is written seems to Glow under the magic Rays by the same principle on altered documents erasers and changes may be brought out so that the attempted alteration is clearly visible mixed in with the visible sunlight and the ultraviolet light is another magic light that our eyes cannot see but which we can feel as heat these invisible rays of heat which form so large a part of sunshine have been given the name infrared light infrared light has no visual effect on our eyes so in order to see its results we must use a camera containing a special film which is sensitive only to infrared light to furnish invisible light for the infrared camera we will use these big electric units which produce no visible light at all and now for the first time on on the motion picture screen we're going to see a picture made entirely by infrared light in a dark room there go the lights and here is the picture taken by the infrared camera and remember to the eye this girl is in total darkness infrared light is very penetrating in its effect with it for example we can even take the young lady's picture while she's hiding behind a screen coated with rubber the magic light shows that even a brand new shave isn't good enough when you are posing for the infrared camera it digs right down and finds the whiskers that haven't even sprouted yet previews a shave 3 days in advance visible white light has also been put under control by science a remarkable new device splits light into separate narrow Rays so that the path of a beam can easily be followed notice that a light spreads out from its source in all directions we can see how a mirror reflects light how a prism bends the Rays in different directions and how light can even be bent around corners in tubes and pipes now let's see the effect of a simple reflecting surface used to control light the Rays leave their Source strike the reflector and bounce back on themselves in the same path then if we place a lens like this in the path of the light the rays are bent inward now let's try another type of lens similar to the lens used in automobile headlights instead of bringing the Rays together at a point point this lens bends them so they go out in parallel lines in the Motorcar headlight the new system of light control makes use of the type of reflecting surface called a parabolic reflector no matter at what angle the light rays strike the reflector they are bounced back in an even parallel path the actual mechanics of this new headlamp are somewhat similar to previous two beam lamps when we are driving in the country light from the central filament is used and an intense beam of light is reflected straight ahead and far down the road when we switch to the passing beam another filament only a few thousandths of an inch away is lighted and the beam is now aimed down and to the right of the road a more accurate lens has been designed to direct light farther ahead in the driving beam and more light on the right right side of the road for the passing beam then the whole unit has been sealed airtight so that air and moisture tarnish and rust cannot cut down its efficiency and so today we drive with headlights that apply the latest principle of scientific light control headlight suited to the speeds at which we travel on the high road controlled light makes possible safe speed because we can always stop within the range of our own headlights in City driving and in passing other cars on the highway our controlled passing beam continues to light the right side of the road without shining in the other fellow's eyes if we drive safely and always dim our lights when passing we can take full advantage of the new control science has given us [Music] and in the Laboratories of today science is working on the light of Tomorrow seeking still more numerous ways of using it to make life for all of us better and safer who knows what Miracles are yet to come from the amazing development of visible and invisible light when the magic light of tomorrow comes into its own go