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He was a draper by trade who ground his own lenses in his spare time. On Septemb
1683 Event

September 17

Van Leeuwenhoek Describes Animalcules: The Invisible World Revealed

He was a draper by trade who ground his own lenses in his spare time. On September 17, 1683, Antonie van Leeuwenhoek wrote to London's Royal Society describing tiny living creatures he'd observed in pond water and scrapings from his own teeth. He called them 'animalcules.' The Royal Society initially doubted him — they sent a delegation to verify his observations. The delegation confirmed everything. What van Leeuwenhoek had found in his Delft workshop, using lenses no one else could replicate at the time, was the invisible world that makes most of life on Earth possible.

September 17, 1683

343 years ago

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