Compound Microscope, by John Marshall, London, c. 1715

Marshall's "Great Double Microscope". The outer body is covered with grey shagreen and the draw tube is in green vellum with gold stampings. At the top the fitting and dust cover for the eyepiece are turned wood. The instrument is supported on a square cross sectioned pillar that fits into a large brass boss on the box base. Focusing is by a screw operated mechanism on the pillar. The base is octagonal with a drawer and a screw tightened accessory mount. Accessories include: six objectives, an opaque stage with a bull's-eye lens, a Bonanni spring stage, brass forceps and a plane mirror in a horseshoe mount.