Word: quartz
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...monster electronic clock, the last word in precision timers, went into operation last week at the Bell Telephone Laboratories in Murray Hill, N.J. The secret of the new clock's accuracy is a set of four quartz crystals, about the size of matchbooks, which vibrate in controlled temperature vacuum chambers at 100,000 cycles per second. Their function: to control the pulses of current which drive the mechanism. Working together with 600 electron tubes, the crystals operate with a margin for error of about one part in a billion...
Last week Harvard Physics Professor Gerald J. Holton told how he found new evidence to prove this theory. He put water in a small cartridge and compressed it up to 180,000 Ibs. per square inch. In one end of the cartridge was a quartz disc which turned electrical impulses into sound waves. When the sound waves had passed through the water-filled cartridge and echoed back, the quartz turned them again into electrical impulses. By measuring with an oscilloscope the energy of the reflected impulses, Professor Holton could tell how much energy the sound waves had lost in passing...
Readers of Barnhart's dictionary will not get a definition of the adjective evil that begins: "Injurious, mischievous." He speaks right up: "Bad; wrong; sinful; wicked." As for agate, he suppresses "a variegated chalcedony" and makes it "a variety of quartz...
Early man-made quartz crystals were too small to be useful. During World War II the Germans did better, but not well enough. Last week Dr. Albert C. Walker of the Bell Telephone Laboratories told a gathering of scientists in Ithaca how Bell engineers had improved the German process until it grows quarter-pound crystals in only two weeks...
...Bell crystals are grown in thick-walled steel "bombs" filled with a water solution of alkaline material (see diagram). At the bottom is a layer of finely ground quartz (silica). A small quartz crystal (it may be only a sliver) is suspended near the top. When the bottom of the bomb is heated to 750°F., and the pressure raised to 15,000 Ibs. per sq. in., the ground quartz dissolves. Its molecules diffuse through the solution. When they reach the cooler top of the chamber, they deposit one by one on the "seed," building it into a perfect...