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Description: | DOLLOND / LONDON
The barrel of this hand-held telescope is covered in rayskin (shagreen) that has been dyed green, while the three draw tubes are made of green vellum. Stop lines marked with dots on the draw tubes indicate the optimum working length of the telescope. The brass fittings include sliding eyepiece and objective lens covers.
The telescope has an achromatic objective lens, the patent for which was taken out by John Dollond (1706?61) in 1758. John's son, Peter (1731?1820), had founded the company whose name is stamped on one of the draw tubes: 'DOLLOND / LONDON'.
Focal Length: 27".O.G.diameter: 0.9".
caption: Pocket telescope | Publisher: | "http://collections.rmg.co.uk/" | Rights holder: | "Royal Museums Greenwich" | Subjects: | Rayskin (shagreen) Vellum Achromatic lens achromatic telescopes Dollond & Aitchison | Source: | Royal Museums Greenwich | Identifier: | http://collections.rmg.co.uk/collections... | Go to resource |
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