Monocular Compound Microscope and Eyepiece

The optical components of this copper alloy microscope are carried on a 'Lister limb' (often called 'Jackson limb'), mounted to one side of the vertical pillar on a flat tripod foot. The curved limb holds a sleeve holding the body tube. The body can be racked up and down within the sleeve, for coarse focusing, by a mill-edged knob at the side of the sleeve. The Huygenian eyepiece pushes into the top of the body. A vertical screw on the side of the lower end of the body moves an inner cylinder, with an internal thread to take objectives, for fine focusing. The mechanical stage has a rectangular upper plate with a sliding bracket for slides. The position of the plate is controlled by a lever on the side of the stage extending below its mounting. Below the circular stage hole is a disk with four apertures that rotates on a click-stop mechanism. A post at the lower end of the limb carries the plano-concave mirror on a horseshoe mount.