June 2024: Science History from 50, 100 and 150 Years Ago

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Walking barefoot on hot stones; what makes bluebirds blue
1974, Spiral Reaction: "Spirals of chemical activity form in a shallow dish of red reagent. A blue ring was induced by touching the surface of the solution with a hot filament, then the dish was rocked to break the ring. The free ends of the fragmented circular wave each curl around a pivot point, winding up into spirals." Photographs were taken over eight minutes.

1974

Pleistocene Humans Found in Ukraine

"The systematic study of Pleistocene humans was first fo­­cused in France. Yet the first occupation sites to be discovered in central and eastern Eu­­rope, many of them spectacularly rich, were unearthed al­­most as long ago. The information they contain is vital to understanding how early humans survived and perhaps even thrived under ice-age conditions in Europe, perhaps best demonstrated by nearly 100 Pleistocene sites in and around the Ukraine. The earliest sites are be­­tween 80,000 and 75,000 years old."

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1924

Walking Barefoot on Red-Hot Stones

"In some parts of Asia the priests, in order to show their magical powers, walk on red-hot stones spread over a fierce fire, without any protection to their feet. This achievement has always puzzled scientists. Many times the feet have been closely examined and have…
Mark Fischetti
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