Word: aids
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Dates: during 1960-1969
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...wounded on the battlefield. It was only the latest in the continuing series of atrocities that the North Vietnamese and Viet Cong have made a deliberate and calculat ed part of their war tactics. With a chilling combination of care and coldbloodedness, they have assassinated pacification leaders, killed U.S. AID workers, decapitated village chiefs, abducted whole hamlets, and murdered prisoners...
After 70% of Israel's hybrid corn crop withered away in 1958, the Israeli Ministry of Agriculture, suspecting that the disease was spread by an insect, called on Harpaz for aid. By 1959 Harpaz had discovered that the corn blight -which he straightforwardly named Rough Dwarf Maize Disease-was caused by a virus. Coping proved more difficult...
...benefit of compass, Viking sailors of the 9th century managed to ply their watery routes of conquest and commerce, navigating by stars at night and by sun during the day. No matter what the weather, according to ancient Scandinavian sagas, the sun could al ways be located with the aid of magical "sun stones." Summarizing sunstone lore in a recent article in the archaeology magazine Skalk, Danish Archaeologist Thorkild Ramskou lamented that none of the sagas clearly describe the sun stone. "But there seems to be a possibility," he wrote, "that it was an instrument which in clouded weather could...
Flight test. Intrigued by his son's observation, Jensen passed it on to Ramskou, who immediately recognized its scientific implication. Enlisting the aid of Denmark's royal-court jeweler, the archaeologist collected minerals found in Scandinavia whose molecules are all aligned parallel to each other, just as the crystals are in a Polaroid filter. Ramskou found that one of these minerals, a transparent crystal called cordierite, turned from yellow to dark blue whenever its natural molecular alignment was held at right angles to the plane of polarized light from the sun. Thus, he reasoned, a Viking could have...
...used the twilight compass. His observations were accurate to within 21° of the sun's true position, and he was able to track the sun until it had dipped 7° below the horizon. "I now feel convinced," Ramskou concludes, "that the old Viking sailors with the aid of their sun stones could navigate with enormous accuracy...