Van Leeuwenhoek had a varied career in his hometown of Delft, Netherlands. He earned money with stints as fabric merchant, surveyor, wine assayer and minor city official. He also served as trustee of the estate of painter Jan Vermeer, who died bankrupt.

One thing he did not do was invent the microscope, regardless of his glorious association with that instrument. Nor did his well-known contemporary, the Englishman Robert Hooke. The compound microscope (using an ocular and an objective lens in series) was invented in the 1590s, some four decades before their birth.

Van Leeuwenhoek, in fact, didn’t even use a compound microscope. Despite the eventual superiority of the concept, the compound designs of his time couldn’t produce a clear image at much more than 20x or 30x magnification.

After seeing Hooke’s illustrated and very popular book Micrographia, van Leeuwenhoek learned to grind lenses some time before 1668, and he began building simple microscopes. This jack-of-all-trades became a master of one.

His simple microscope design used a single lens mounted in a brass plate. A sharp point held the specimen for examination. One screw moved the specimen into position in front of the lens, and another screw moved it backward or forward into focus.

According to weird