@sciencefunn: In 1861, Crookes discovered thallium, a highly toxic, heavy metal. While weighing samples of it in a vacuum to determine its atomic weight, he noticed something bizarre: the element seemed to weigh less when it was exposed to sunlight than when it was in the dark. Instead of assuming his scale was broken, Crookes—who was deeply into the Spiritualism movement popular in Victorian England—wondered if he had accidentally discovered a physical link to the spirit world. He thought he might be measuring a “radiant force” that could explain how ghosts interact with the material world. To test this “ghost force,” he built a device consisting of a glass bulb containing a fine spindle with four vanes, each painted black on one side and silver on the other. When light hit it, the vanes spun rapidly in a vacuum. Crookes initially believed this light-powered spinning device, now known as the Crookes radiometer, proved the existence of a new psychic force. Eventually, the physics community stepped in. Titans of science like James Clerk Maxwell and Osborne Reynolds proved that the spinning had nothing to do with spirits or the pressure of light itself. Instead, it was caused by residual gas molecules in the bulb getting heated more by the black sides of the vanes than the silver ones, creating a tiny thermal currents that kicked the vanes forward. So, while attempting to isolate element 81 and build a scientific bridge to the afterlife, Crookes accidentally invented a classic science toy that you can still buy in museum gift shops today. We share the finest science memes, feel free to join us for more.

Science Is Fun

Open In TikTok:

Region: SK

Monday 03 August 2026 17:50:55 GMT