This étui functions as a Galilean monocular (spyglass or perspective glass). It is a rare survival, with the enamel in perfect condition. This instrument is the subject of an article in the September 2014 edition of the Bulletin of the Scientific Instrument Society. Thomas Ribright patented the design in 1749. This example in Bilston enamel and gilt brass, can be dated to about 1765 as it is in the early style if Bilston enamel decorative work. Ribright worked from 1735 to 1772.
Although this example of Ribright’s work is not signed, the cast decoration of the silver-gilt fruit knife corresponds with the design in Ribright’s patent, confirming the attribution. Full details of the instrument are provided in the Bulletin article.
References: Patents Connected with the microscope 1666-1800 –Royal Microscopical Society 1895
Thomas Ribright of London: An Exquisite Bilston Enamel Mercury Gilt Ladies Pocket Étui with a Perspective Glass – Stuart Talbot FRAS, Scientific Society Bulletin Sept. 2014.
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Ganymede Antiques, established in 1992, is based in Muswell Hill, London, U.K. We specialise in scientific instruments from the 18th and early 19th centuries, with particular interest in sundials, and drawing and calculating instruments. We are always keen to buy interesting instruments, and entire collections. We exhibit at the twice yearly International Antique Scientific Instrument Fair in London. Keith Petts can be contacted at firstname.lastname@example.org