How many of van Leeuwenhoek's microscopes are left today?

Answer 1

Simple Answer:

Only nine of van Leeuwenhoek's microscopes are left today.

Longer Answer:

Anton van Leeuwenhoek's technical advancement was primarily that he invented a method for making small spherical lenses that much increased magnification of simple microscopes.

Beyond the discovery of the methods for making small spherical lenses, van Leeuwenhoek also built microscopes and experimented with their design, addressing the difficult problems of illuminating, holding and viewing the specimens.

He made over 500 optical lenses, though they did not necessarily go into 500 different microscopes. The microscopes themselves were expensive and time consuming to construct, but records indicate possibly as many as two hundred were made. In this process he is said to have created at least 25 variations on the basic design of the microscope.

Only nine of his microscopes are known to exist today.