Compound microscope

This microscope tube has a consistent diameter and houses the eyepiece and lens. An arm attaches it to the quadrangular pillar and it moves vertically using 2 side screws for coarse focusing. Fine focusing is achieved using a screw at the very top of the pillar. The rectangular stage is fixed in place and has a large central hole to let light pass through. At the far end of the pillar is the plano-concave mirror, which can move in all directions thanks to its arm. The tube is connected to a double triangular pedestal using an articulated screw. The base is horseshoe-shaped with wide ends. On the heel is the inscription: "ROSS. London. 3510."

Andrew Ross (1798–1859) was a famous London microscope maker who worked with J. J. Lister. Together they founded the Microscopical Society of London, later known as the Royal Microscopical Society. He made a series of improvements to the microscope and won first prize at the 1851 Great Exhibition. His microscopes bore the "Ross & Co." name until 1842 when his collaboration with Lister ended. He then began to number his microscopes and signed them "A. Ross," producing around 1,800 instruments. When he died the business continued under the leadership of his son, Thomas Ross, and its name changed simply to "Ross." Thomas continued his father's numbering, as can be seen with this model. Under Thomas' leadership, the business maintained its prestige until 1906 when it became part of "Swift & Son," whose founder, James Swift, had been employed by Andrew Ross.