Word: radars
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Dates: during 1940-1949
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...with the town all but cut off, with electricity gone and with thick, fire-reddened clouds of smoke whipping everywhere, 2,000 people-mostly women and children-gathered on the town pier. Fishing boats and Coast Guard vessels, some of which were forced to maneuver through the smoke with radar, began taking them aboard. Hundreds crossed to the mainland through heavy, gale-driven seas. Then Army bulldozers opened the road and automobiles began running the fiery gauntlet again...
...weather flying" is here, but not for the public. Colonel J. Francis Taylor, deputy commander of the Air Force's All-Weather Flying Center at Wilmington, Ohio, said last week that for 14 months his outfit has flown a daily, round-trip schedule from Ohio to Maryland. Radar and G.C.A. (Ground Controlled Approach) got the planes through safely and landed them in zero-zero soup. It was always "instrument weather" for the pilots, who kept their cockpits hooded on every flight...
Airlines have been slow to go for radar. The sets are expensive and cut payload. But this week the Peruvian International Airways started the first regularly scheduled passenger service (between New York and Santiago, Chile) completely safeguarded by radar. P.I.A.'s radars (made by General Electric) weigh 150 lbs. in all, but show a clear map of the country below. The pilot knows where he is-and where the obstacles are-in all weathers...
...Dirac theory predicts, among many other things, that hydrogen atoms can exist in two different "states"-one stable, the other unstable-which contain the same amount of energy. Lamb & Retherford checked up with ultrashort radio waves (war-developed for radar), and found that this prediction was not correct...
Extra Energy. Radar waves are electromagnetic waves like light and X rays; but since their frequency is enormously smaller, they carry much less energy per "photon."* They therefore provide what scientists call an "elegant" method of dealing out very small quantities of energy. Using a formidable-looking gadget, Lamb & Retherford shot radar waves of the proper frequency through hydrogen atoms in one of Dirac's predicted states. As soon as the energy was added, the atoms turned into the other state. Since energy was required to make the change, the experiment showed that the two states did not have...