Compound Microscope in Case with Accessories, by Smith & Beck, London, c.1855

This copper alloy instrument has a Wenham binocular body with rack and pinions to adjust the intraocular distance, with two eyepieces slotted into the top. The body is carried on a rack and pinion, for coarse focusing, on the shaped limb. A micrometre screw for fine focusing is set at the lower end of the body. The limb is held on trunnions on two pillars which stand on a disc on the flat tripod base. The circular stage is attached to the limb at the level of the trunnions. The mechanical stage plate, moved by two knobs, has a bracket with to hold specimens that slides in dovetail grooves. Below the stage is a mounting for a condenser which also carries an aperture disk and an Iris diaphragm. A post with a triangular cross section extends below the stage and a sliding sleeve supports the Plano-concave mirror on a pivoting arm. The wooden case holds a monocular draw tube, a rectangular stage and two boxes of accessories. These contain two eyepieces, three objectives in cans, an epi-illuminator, an erector lens, copper alloy hand forceps, stage forceps, bull's-eye lens on a copper alloy pin, two nosepiece adaptors with screw threads, two glass plates with ledges, an ivory wedge for use with a glass trough, a bracket with three selenite discs, a Wenham parabolic condenser with an adjustable central stop, a Nicol prism analyser, three eyepiece analysers, an Amici prism on a sliding bar, a sub stage collar on an arm with a triangular hole, a painted slide, a rectangular slide holder, a curved bracket with a steel screw, pointer on an adjustable screw, two slide-on barrel adapters and a set of keys for the case.