Simple microscopes, 17th century.

Simple microscopes by Leeuwenhoek, copy, Muschenbroete and Depouilly. The Leeuwenhoek is an exact copy of the original, made before 1673 and in the posesion of the University Museum, Utrecht. It consists of a double convex lens mounted between two concavities, provided with minute apertures made in two thin bras plates which are riveted together. The object to be examined is held in front of the lens on the point of a short rod mounted on a small bras block loosely riveted to a long coarse-threaded screw. Blue background.