Word: quartz
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Dates: during 1920-1929
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...British Medical Research Council last week decried the use of light treatments. There are two general kinds of light used in medicine-heat-producing, generated by carbon filaments; and ultraviolet ray (artificial sunlight) producing, generated by a carbon arc, by a mercury arc, or by special filaments lighting through quartz. Undoubtedly such lights have done good. This is particularly so of the ultraviolet light, used to overcome rickets by direct exposure of puny children...
...done in three years, will double the astronomer's vision, quadruple the amount of light that at present can be caught from the stars. The great mirror, about 17 feet in diameter, is possible because Professor Elihu Thomson of the General Electric Co. has learned how to fuse quartz into great discs that will not crack, nor warp with heat...
...years later, a little man, almost buried in a great shock of hair and beard, came up from Colorado and began to deepen the Butte pits. William A. Clark learned his trade in a quartz mine and lost his savings in a gold mine. In Butte, he dug for copper. Gold miners, seeing his wagons start out on their 400-mile trek to the nearest railroad at Corinne, Utah, laughed aloud. "There go Clark's rocks," they jeered. And they were 98.37% right. Only 1.63% of the gray copper ore can be reduced to valuable metal...
...grind through the rock with drills. All day the air is filled with minute particles of stone, deadly dangerous dust is sucked into human lungs with every breath. The dust varies according to the stone, but wherever there is quartz, flint, ganister, sandstone, granite, there silica particles lead all the rest. These tiny glasslike fragments do not dissolve in the moisture of the nasal passages. Sharp-edged, insoluble, they penetrate the lungs, enter the cells. The crowded cells clump together. In an effort to protect the body, fibres begin to grow around the "clumps." Gradually the lungs choke up with...
...rain. The new light in Virginia is five times as large and bright as this biggest and brightest light in Illinois. When 17,200 watts of current are turned on, the crater of the new light's arc becomes the hottest spot on earth-38,000° Fahrenheit. Quartz prisms in the 62-inch globe absorb so much of this heat that the light, passing off with an intensity of 1,385,000,000 candle power,* will not blister the skin of persons keeping more than 1,000 feet distant. Engineers predicted that on clear nights the Monticello beam...