Word: light
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Dates: during 1930-1939
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Splitting Light. The important work which Robert Williams Wood is now doing is the manufacture of diffraction gratings. A diffraction grating is a plate of glass, metal or metal-on-glass on which a series of very fine, parallel lines are ruled close together. In combination with lenses, such a grating breaks up a beam of mixed light, such as the light from a star, into its component wave lengths-that is, it furnishes, as a prism does, a spectrum of bright and dark lines which identify the fundamental elements of matter. The iridescence of mother-of-pearl...
...inches in diameter, which he intended to use as a spectroscope tube. There were cobwebs in the pipe which had to be cleaned out. Dr. Wood obtained a cat, put the cat in the pipe, closed up that end by laying a board against it. The cat saw light at the opposite end, crawled through the tube and emerged, having cleaned out the cobwebs...
...Raman Effect: multiplication of spectrum lines when light is scattered by molecules of a transparent substance...
...heart of "Johnny" Green's invention is his use of a tiny beam of light and a photo-electric cell. Whether in the transmitter or in the linotype activator, the light is focused on the coded dot combinations and reflected into the photocell. The varying combinations cause correspondingly varying pulsations in the photocell. These pulsations actuate the appropriate mechanisms in the telegraph printer and in the linotype (or Intertype). Its inventor claims that the speed of the Semagraph is limited only by the speed of the linotype. The number of teletype printers that can receive Semagraph copy from...
...annual yield topped a billion bushels. Last week's estimates, however, placed the 1938 yield between 1,020,623,000 and 1,045,623,000 bu., on top of a 200,000,000-bu. carryover. Annual U. S. consumption is about half this stupendous total. With light crops in England, Italy and North Africa, there is a slim chance the U. S. may export a sizable share of its surplus. Hope on this score plus rumors of black rust last week jumped prices on the Chicago wheat exchange 4½? a bu. day after the report was issued...