Microscopes, 18th Century Modified Marshall type compound microscope, 1720

Microscopes, 18th Century Modified Marshall type compound microscope, 1720. Following the publication of Robert HookeÕs ÔMicrographiaÕ in 1665, English makers, notably John Marshall (1663-1725) began to produce large compound microscopes based on HookeÕs design. Although this instrument resembles those made by Marshall in general form, it differs from them in several important respects. The pillar is fixed vertical, with the ball-and-socket joint of earlier instruments having been dispensed with. The microscope is also fitted with a plane illuminating mirror which does not appear to have been fitted to any of MarshallÕs instruments. Optically the instrument is very much of the Marshall form, there being a single-lens objective, a large field lens and an eye-lens. ©SSPL/Science Museum