The compound microscope was born in the Netherlands toward the end of the 16th century, probably among optical craftsmen in Middelburg. Tradition attributes the invention to Hans and Zacharias Janssen, though the attribution is historically disputed and there is no contemporary primary document confirming it unambiguously. What is incontrovertible is the principle: combining an objective lens and an eyepiece lens to multiply magnification beyond what is possible with a single lens. That principle would open the way for Hooke and Leeuwenhoek, and through them, to modern microscopic biology.