Andrew Ross (1798-1859) was one of the most prestigious makers of microscopes in London in the Victorian era and one of the best known in history. He started his business in collaboration with J.J. Lister, inventor of a novel system for manufacturing achromatic lenses and together with Hugh Powell and James Smith, developed some of the most valuable microscopes of the 19th century. They all founded the Microscopical Society of London (later the Royal Microscopical Society) which standardized and greatly contributed to the advancement of microscopy. A model built by Ross won the main prize at the great exhibition of 1851. He signed his instruments with the name of Rofs and did not begin numbering them until 1842, so it is difficult to date his earlier creations. He died in 1859 after making some 1,900 copies. His son Thjomas inherited the business which continued to function with considerable prestige until the end of the century.
This delicate and beautiful microscope was built by Andrew Ross between 1845 and 1846 according to its number (221). It is engraved with the name Rofs, a name he used to identify his microscopes. Its state of conservation is very good, maintaining most of the original lacquer, with some specks and scratches typical of use. All the controls work correctly, highlighting the smooth movement of the rack and pinion mechanism and the fine focus micrometer, located on the side of the tube, an option that he only used in a few instruments. It also highlights the fact that all of them are located on the right side. The observation platform is tiltable, something unusual in those years, so I would dare to say that it is one of the first built with this possibility. In addition, this same platform is equipped with an X-Y micrometric movement mechanism to correctly center the samples. It retains 6 lenses, all of them original from the same manufacturer, although some seem to have been added later. Together with the 2 eyepieces, it allows a wide range of possible magnifications for observation. Other accessories that complete it are a light-concentrating magnifying glass and a "live-box" for observing live insects. The box is in good condition although the key is missing. Its height in working position exceeds 40 cm.
References: "Billings Microscope Collection" pag 43, fig. 80
G. Turner, "Great Age of the Microscope", pag 154-170
G. Turner, "Collecting Microscopes", pag 71
H. Moe, "The Story of the Microscope", pag 155-164