Word: instrumental
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Dates: during 1940-1949
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About ten years ago, Drs. Roy D. McClure and Frank W. Hartman of Detroit's Ford Hospital began experimenting with a photoelectric cell technique first developed in Germany. Later they were joined by Physiologist Vivian Gould Behrmann. Together the experimenters worked out an instrument which gives an almost instantaneous record of the amount of oxygen in the blood...
White Worms. One instrument, the spectroheliograph, takes pictures of the sun in the light that comes from single elements, such as hydrogen or calcium. The instrument has recently been improved to the point where it can take motion pictures (spectroheliokinemato-grams) which show the sun covered with patches, streaks and mottlings, most of them in motion. The pattern of the mottled background often changes completely in 15 minutes. "Motion pictures of the surface," says Dr. Menzel, "present a sort of 'crawly' appearance-like white worms in a pile of carrion...
...would be even harder without a new tool: nitrogen 15, a stable (nonradioactive) isotope of nitrogen. Chemically, nitrogen 15 is exactly like the common nitrogen 14. The cells cannot tell the difference. But since it is slightly heavier, nitrogen 15 can be measured accurately by a balky and expensive instrument called a mass spectrometer. If compounds containing nitrogen 15 instead of ordinary nitrogen are fed to cells, the scientists can tell with the mass spectrometer whether the cells have accepted them as food...
Such great telescopes as the 200-incher on Mt. Palomar see only tiny patches of sky. They need a more wide-eyed instrument to tell them where to look. Last week CalTech and the National Geographic Society announced a joint project to map the whole sky in search of interesting objects for big telescopes to study in detail. The society will supply the funds; CalTech, which runs Palomar Observatory, will supply the Schmidt telescope to do the mapping...
...Schmidt reaches about 300 million light-years into space-less than one-third as far as the 200-in. - but it is more efficient than any earlier instrument designed for survey of the sky. As the Schmidt's pictures become available, astronomers all over the world will study them eagerly...