Compound Microscope with Accessories and Eyepieces, by Ross, London, c. 1880

This copper alloy instrument is carried on trunnions standing on a flat tripod foot. The limb has a rectangular cross section and the Wenham binocular body tube is held on a rack and pinion, operated by two double mill-edged knobs, for coarse focusing. There are two eyepieces each with eyecups fitted into the top of the body tube. A graduated screw on the limb operates the fine focus. The circular stage has a mechanical plate that can rotate and is graduated in degrees. It is mounted on the limb at the level of the trunnions. A substage assembly, to hold a condenser, is mounted on a rack and pinion below the stage. Below this a plano-concave mirror is mounted on a pivoting arm. The microscope also has the following accessories: An additional single eyepiece labelled 'E'; A Nicol prism analyser; A Wollaston camera lucida with two rotating lenses.