Word: pile
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Shackles to Studies. Fisk began in 1866, in abandoned Union hospital barracks, and its first books were bought by selling a pile of old iron handcuffs found in the barracks. Most of the first students were freed slaves, who had to start from scratch, work up from the three Rs to college subjects (some took ten years). Eleven of the students barnstormed the U.S. and Europe as the "Fisk Jubilee Singers," in three years raised $100,000 for the University by singing spirituals...
Harry Lacey, a Boston interior the Rubens' painting, "Descent from the Rubens' painting, "Descent from the Cross," to the Fogg Art Museum, it was reported early today. Lacey allegedly had no knowledge of the value of the print, and recovered it from a pile of debris in the basement of the Boston Art Club...
Fishing Probabilities. Swaggering little Enrico Fermi, who put the match to history's first atomic chain reaction, led off with a circumstantial account of how a chain-reacting pile works...
...typical pile is a 20-foot block of graphite (pure carbon) interlarded with lumps of fissionable uranium. The chain begins with the capture of a neutron by a uranium atom. When the atom "fishes" (splits by fission), neutrons released by the reaction fly off at more than 6,000 miles a second. To give the neutrons a maximum chance of being captured by other uranium atoms, they are slowed to "thermal" speed-roughly 3 m.p.s. Normally a neutron slows down to that speed after about 110 collisions with carbon atoms...
...controlling fission, the nuclear physicists' big problem was to calculate the probability that a given atom would capture a neutron traveling at a given speed. They found that in a certain type of pile the critical size at which a lump of enriched uranium begins to cook in a nonexplosive chain reaction is 1.5 kilograms (about 3⅓ Ibs.). Theoretically, a pile might heat up to the temperature of the sun (over 6,000°), but no known container can withstand more than 1,500°. The physicists discovered that the simplest way to throttle down a pile...