Twenty-six of Leeuwenhoek’s microscopes are very likely still in existence, lying in a dusty attic in London , unrecognized. Of the nine known to be associated with his name, one was discovered a few years ago in a discarded box of laboratory oddments. Other microscopes of the greatest historic importance have turned up in cupboards, in private collections, and one was returned to a learned society in London after being bought up in a house sale in Dorset.

There is every reason to rehabilitate the simple microscopes. As historic relics they have a fascination of their own, but as an overlooked facet of scientific history their interest is paramount. In fact there is a further theme of the discussion, there is good reason to believe that this much-misunderstood, widely ignored instrument has a more important niche in our history than even these considerations might suggest.

If we realign the way the construction of the microscope is seen to have developed, then the simple microscope emerges as the clear ancestor to today’s laboratory instrument. The principles of design were not merely peculiar to simple microscopes, but laid the foundations for the magnificent-looking brass and lacquer constructions of a hundred years ago. More important still, the designs of today’s research microscopes have more in common with the simple microscopes of the early 1800s than with the compound microscopes of the early days.