Word: x-rayed
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...when Professor Hermann J. Muller. now of Indiana University, discovered that X rays applied to fruit flies or any other living organism, create a wealth of mutations, apparently by damaging the genes in their chromosomes. Muller, too, won a Nobel Prize, and soon most genetics laboratories had X-ray machines and were buzzing with dwarfed, twisted, crippled or half-alive fruit flies whose ancestors had been Xrayed...
When Muller made this discovery, he may have heard a roll of distant thunder, but he could not have known what it meant. In the year 1926, long before Hiroshima, no man-made radioactivity was at large on earth outside the range of X-ray machines and radium capsules, and none was expected. No one suspected that in less than 20 years the mutation-producing effects of radiation would be a worldwide worry...
This was what Beadle had been hoping for. His explanation is that the gene damaged by X-ray violence was originally responsible for producing an enzyme (organic catalyst) needed in the mold's process of making vitamin B-6 out of simpler nutrients. With the gene out of action, the process stopped, and the mold could not grow without help. It was like a human diabetic who needs an external source of the insulin that his body cannot make...
...that year, James D. Watson and Francis H.C. Crick in England went a step farther. DNA, they said, is a double helix with two spirally rising chains of linked atomic groups and a series of horizontal members, like steps, connecting the two spirals. This molecular model, deduced mostly from X-ray diffraction photos, seemed complex and unlikely, but geneticists rejoiced when they heard about it. It was just what they" needed to explain many perplexing things that they had been observing for years (see diagram...
...shelter shortly after World War II. More important, the Swedes discovered that building underground-in terms of construction and maintenance-often costs less. Airplanes, precision instruments, munitions, radios are also made in below-ground factories; hydroelectric power is generated in stations tucked inside mountains; cavernous hospitals are complete with X-ray rooms, operating theaters, fully equipped wards...