3 Robert Hooke
contributed to fields as diverse as astronomy, architecture, paleontology, and
physics, but his most important accomplishment was in biology. In 1665, he
built his own compound microscope and began exploring. When he peered through
its lenses at a thin slice of corkwood, he saw infinitesimal rectangles that
reminded him of monks’ cells. Hooke thereby discovered biological cells, the
fundamental unit of all organisms.
2 In 1896, physicist Henri Becquerel was fascinated by the recently discovered X-ray. He thought that naturally fluorescent minerals produced X-rays after prolonged exposure to sunlight. To test his theory, he let mineral samples soak up the sun and then wrapped them in black cloth with a photographic plate, expecting the resulting X-rays to create weak images. On a February day too overcast to work, Becquerel wrapped up a plate with a sample of uranium and left it in a drawer for the next few days. By the time he opened the bundle, the uranium had burned its own image on the film, as clear as if it had been exposed to bright sunlight. Something in the rock released more energy than weak phosphorescence could explain. Upon further investigation, he and Marie and Pierre Curie discovered that that something was radioactivity.
Alexander Flemming
Image courtesy of
the USDA
1 In 1928, Alexander Fleming had the archetypal eureka moment—and unlike the tale of Archimedes, this one’s true. Believing that there was a substance in snot that worked as an antibiotic, he smeared a set of Petri dishes with bacteria and his own special Fleming phlegm, and left the dishes while he took a two-week vacation. When he returned, the mucus had not killed any of the bacteria, but mold had drifted in from a nearby lab and contaminated one dish. All the bacteria close to the mold were dead. Closer examination of the mold showed that it was producing a chemical—penicillin—that killed the bacteria.
As with any top-whatever list, picking the best eureka moments is a judgment call; from where we’re sitting it seems that Fleming’s discovery was truly a momentous event, that Newton probably didn’t get pelted in the head with an apple, and that Descartes most likely did lie in bed and watch flies (it was, after all, the 17th century).
Think we erred egregiously? Left someone out? Speak your mind at the blog post.
