Compound Microscope with Case by R. & J. Beck, London, c.1866

The binocular body is mounted on a rack and pinion, for focusing, on the shaped limb. The inter-ocular distance is adjusted by a knob near the top of the body. At the lower end of the body a vertical screw adjusts the fine focus. The nose has an external thread to take objectives or one of the objective changers. The limb is carried on trunnions on two pillars that stand on the flat tripod foot. The circular rotating stage is attached to the limb at the level of the trunnions. Three knobs adjust the position of the mechanical stage plate which has a sliding bracket with a pinhole, to hold specimens and accessories.

A rack and pinion is set below the stage to take substage accessories. A post with a triangular cross section extends beneath the stage and a sliding sleeve supports the plano-concave mirror. The instrument stands on a board that slides into the mahogany case. Accessories include a monocular copper alloy draw tube, a leather covered box lined with purple silk and velvet, containing two fittings, a triple and two double objective changers and two substage parabolic condensers. There is also a accessory box containing seven objectives in cans, three eyepieces, a substage condenser with an aperture disk, a bull's eye lens to mount on the limb and another on a stand with a circular base, an Amici prism, a parabolic side reflector, a rotating disk of filters in a copper alloy mount, stage forceps, a camera lucida, a specimen chamber on a copper alloy plate, a glass stage plate and a wooden coverslip box.

Note: there is a mistake in the serial number in the RMS book for the entry for this microscope - It is incorrectly recorded as 4925 when it should be 4923