Antoni van Leeuwenhoek

Born in Delft in 1632, Antonie van Leeuwenhoek did not follow the usual path of a scholar. He worked in trade and city government, but in his spare time he became deeply skilled at making simple microscopes with remarkably powerful lenses. With those handmade instruments, he studied water, insects, plants, and the human body in extraordinary detail.

Through letters sent over many years to the Royal Society in London, he reported things no one had clearly seen before, including microscopic life in pond water, bacteria, red blood cells, and sperm cells. His work impressed leading scientists of the day because he described what he saw with patience and precision, even though he was largely self-taught.

Van Leeuwenhoek died in Delft in 1723, but his reputation only grew. He is often remembered as a founder of microbiology because he revealed that an entire hidden world of living things existed beyond ordinary sight.