Word: quartz
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Adsorbing Gel. One of the most efficient adsorbent materials known, silica gel was first produced commercially (for use in gas masks) in World War I. It also has industrial uses as a dehydrator and catalyst. Made by drying a gelatinous form of silicon dioxide, silica gel looks like crushed quartz, is riddled with invisible pores so numerous that a cubic inch has more than 50,000 square feet of interior surface. By adsorption (sticking of moisture to the surface), silica gel can hold half its own weight in water without swelling, caking or developing a visible sweat...
Wafers of Accuracy. Sawed into thin slabs, usually no bigger or thicker than a postage stamp, quartz determines a radio sending or receiving channel with hairbreadth accuracy. Tanks with quartz oscillators, for instance, can converse in battle without enemy interference, changing frequencies merely by changing crystals. Using quartz controls, radio stations stay on the beam; hundreds of conversations ride pickaback along a single telephone circuit and are properly unscrambled at the receiving...
...uncanny accuracy of quartz crystals in frequency control demands unyielding accuracy in manufacture. The wafers must be cut with due attention to the structure of the mother crystal, must be ground to within a ten-thousandth of an inch...
Since Pearl Harbor the industry has expanded over 200 times. Diamond-cutting methods now used by most manufacturers have speeded up production, cut down waste. The best crystals come from inland Brazil, but WPB is pushing U.S. exploration. The Japs, incidentally, in 1930 bought up a tidy supply of quartz crystals which were an unwanted byproduct of California gold mining. Every Jap communications set captured so far has been quartz-equipped...
...important is the right kind of crystal that the Signal Corps last month set up a special inspection laboratory in Rio de Janeiro, and plans for the mechanization of quartz mining are well under way. The sentiments of the Signal Corps are visible in a big poster which hangs in many a cutting room. It reads, "GIVE US THE CRYSTALS AND WE'LL PUT THE ... -------ON THE RUN." In radio code the dots & dashes spell...