Word: hardens
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Dates: during 1940-1949
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...Harden Smith '46, 21, Chicago, Lowell House, Government, P. B. H. settlement house coach, House dance committee, Glee Club, House football...
...both sides remained where they were last week, there was real danger that the two blocs would harden into the kind of opposition that would make U.N. a futility. If the West gave way again, there was the even greater danger that the Russians would interpret this as weakness...
...lamp filaments, had developed an efficient method for extracting and refining uranium. Their metal was the purest available, and an occasional dribble of thumb-size pellets filled the modest requirements of college and research laboratories. Then the telephone call came. Dr. Harvey C. Rentschler and Dr. John W. Harden were not dismayed...
Washtubs & Sun Lamps. The three-ton question allowed no time for designing or building machinery. Dr. Harden used his laboratory as a factory and tried every short cut he could think of. First step was pouring a solution of uranium salt and other chemicals into a battery of wooden washtubs on the roof. There the photochemical action of the ultraviolet rays in sunlight (on cloudy days, sun lamps) converted the transparent liquid into green, powdery potassium uranium fluoride. The second step: melting this secondary uranium salt in graphite cups for electrolytic separation of the pure metal. The electrodes were raised...
Within a few months, daily uranium output was stepped up from eight ounces to more than 500 lbs., and the cost dropped from $1,000 a lb. to $22. By 1943, bigger & better production methods were ready to take over, and Drs. Rentschler & Harden were able to quit their little makeshift. But in the emergency, they had supplied more than the asked-for three tons of pure uranium, for the first atomic pile...