Dutch draper and pioneering microbiologist Antonie van Leeuwenhoek (1632–1723), a contemporary of artist Vermeer (and an executor for Vermeer when he died in 1675) in Delft was known to have exceptional lens making skills, having created single small lenses capable of 200x magnification, far exceeding those of more complex compound microscopes of the period. Indeed, his feats of lens making were not matched for a considerable time as he kept aspects of their construction secret; in the 1950s, C.L. Stong used thin glass thread fusing instead of polishing to recreate Leeuwenhoek design microscopes. It was long believed that Antonie van Leeuwenhoek was a master lens grinder (a notion repeated in the recent BBC television documentary "Cell"). However, it is now believed that he came upon a relatively simple method of making small, high quality glass spheres by heating and manipulating a small rod of soda lime glass.