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"Lawrence had tablets of sodium chloride made up containing extremely small percentages of Na²⁴. During lecture demonstrations, he would swallow one of these tablets and then, holding his hand over a Geiger-Müller counter, demonstrate how the radiosodium reached his hand following absorption in the stomach and circulation via the blood stream. The counting rate exhibited by his hand also declined during the lecture, demonstrating both the radiologic and the biologic decay times."

"For a few years the crews working at the cyclotron took no precautions whatsoever against radiation injury. Kurie sat on the yoke of the cyclotron magnet for ten full hours of running time, operating his cloud chamber by hand. Dean Cowie aligned the cyclotron beam by eye*, looking directly at the target lighted by the impact of the beam ions while the neutrons came on through the window into his eyes. As the cyclotron was perfected to produce 10-MeV ions, a window was devised to permit the ion beam to emerge into the air. It was a fascinating sight; the air glowed a beautiful purple for a distance of more than a meter beyond the window. While it is true that no one was so foolhardy as to put a finger into the beam, observers, including me, did stand right beside it. One trick that was repeated for all newcomers was to give them a transparent calcite crystal approximately 2 cm on an edge and a pair of crucible tongs to hold the calcite in the beam. After about a minute, the calcite glowed with a deep red phosphorescence that made it appear to be red hot, even when withdrawn from the beam. To add to the newcomer's amazement, one of the staff members then suddenly dropped the "red hot" crystal into the visitor's hand. The calcite was stone cold, the red radiation notwithstanding; whether it was radioactively hot, no one knew. No statistically meaningful data of long-term consequences of radiation exposure appear to exist, although Cowie suffered cataracts a few years later."

"More than once, the entire campus electrical supply was blown out by a cyclotron malfunction. For a period, while the cyclotron D's were still mounted on large Pyrex insulators with central conductors to carry in the radio frequency power, a startling beam-like glow discharge would occur that terminated on one of these insulators and melted a hole through it in a matter of seconds. The abrupt loss of vacuum, under full power operation, was devastating. Such a failure occurred many times, at about three-week intervals, until it was finally found that the entire radio frequency system had no dc ground at all. Collections of ions in an irregular and unpredictable way could lead to dc charging of the entire system of D's to very high voltages, leading ultimately to dc discharges in the low-pressure residual gas."

(Robert N. Varney. Some physics not in The Physical Review)