Word: infra
(lookup in dictionary)
(lookup stats)
Dates: all
Sort By: most recent first
(reverse)
...thermoelectric sextant, using infra-red rays, invented by Paul Humphrey Macneil. The infra-red rays are in the long-wave end of the electromagnetic spectrum. They are really heat waves, capable of penetrating clouds. The Macneil Sextant has a curved reflector that collects and potently focuses infra-red rays on a thermocouple, two pieces of metal which when heated even one-millionth of 1° give off a tiny flow of electricity. This flow is enormously amplified, measured by a galvanometer. When the curved reflector is pointed directly at the sun, the flow of electricity is greatest and the navigator...
...Observatory plans to do all possible work in the field of the photographic nature of the sun's corona in light of different colors, ranging from the invisible ultra-violet to the black light of the infra-red rays. For use in this photography, four cameras will be taken into the Maine woods. Another phase of the investigations will include the measuring of the total brightness of the coronal light...
...electromagnetic waves-from the very short, very rapid cosmic rays (.000,000,000,004 cm.)* to the comparatively long, slow radio waves (2,500,000 cm.)†only a small section is perceptible to unaided human senses. That section contains light rays and heat rays, and the intermediate infra-red rays which are neither light nor heat, yet are of the nature of both. Scientists are gradually learning how to put the infra-red rays to work. Doctors use them to create artificial fevers. Practical physicists used them otherwise last week...
...dozen industrialists and research engineers sat in pitch blackness. They were on tour of various industrial research laboratories and had stopped at George Eastman's kodak plant for Dr. Charles Edward Kenneth Mees to take their pictures in the dark. The room they posed in was flooded with infra-red light from an airtight, light-tight cabinet. A camera was loaded with a proper plate. The camera clicked a one-second exposure. The lights went on. While the businessmen blinked their eyes and chatted, photographers developed the plate, made prints. Fifteen minutes later the businessmen could see themselves...
Another demonstration of infra-red use occurred last week on the roof of England's Croydon Airdrome control tower. There Paul Humphrey MacNeil of Huntington, L. I. showed his infra-red sextant. Navigators locate their position at sea or in the air by determining how high the sun is above the horizon. They "shoot the sun" through the eyepiece of a sextant. If the day is cloudy, they cannot see the sun, although they may know its approximate location. The MacNeil sextant is connected with an amplifier sensitive to the sun's infra-red rays. Those rays...