Antique Naval Telescope by Thomas Ross
This is a complete example of a naval telescope made by the Ross Family. This business was started in 1830 by the renowned instrument maker, Andrew Ross. His son Thomas Ross took over the businness in 1860 based in Clerkenwell, London, and worked until 1872. Thereafter the firm was known as Ross & Co. This instrument is constructed from German Silver, an alloy with a high percentage of nickel present, this gave naval instuments good protection from corrosion whilst at sea. The single draw (excluding zoom) is engraved:
Ross,
London
No 23099.
This example has a zoom eyepiece which is engraved with three powers 20, 25 and 30x. The Telescope measures a large 25 inches long, which extends to 32.5 at full power. The quality of the image is enhanced by the use of an acromatic objective lens that can be seen below. The objective lens cover is also present.
A similar (Officer of the Watch) telescope housed in the National Maritime Museum, has an identical engraving with a later serial number:
Photograph: National Maritime Museum
