Maker: Dollond

Year: 1770 c.

Year Range: -

Year Notes:

Manufacturing Location: London, England

Signature: Dollond / London

Signature Notes:

Inscriptions:

Stand present.

Collection: National Maritime Museum

Accession #: NAV1516

Sources:

Royal Museums Greenwich. "Miniature folding telescope". http://collections.rmg.co.uk/collections/objects/43728.html [Accessed: June 2016].

Public Notes:

"This brass telescope has a single draw tube and a tripod stand that fits inside when the telescope is not in use. The eyepiece has a thumbwheel, which allows the magnification of the telescope to be changed by selecting one of four numbered lenses. Numbered stop lines engraved on the draw tube correspond to each of the lenses and indicate the appropriate working length of the telescope. Inside the eyepiece assembly there is a smoked-glass filter that can be moved in front of the eyepiece lens in very bright conditions. The maker's name, 'Dollond / London', is inscribed on the draw tube. The company was one of the leading makers of optical instruments in London from the 18th century onwards" (Royal Museums Greenwich).

Length (open): 165

Length (closed): 118

F-ratio:

Exit pupil:

Object status:

Objective type: doublet (unknown)

Optical style multiple eyepiece units

Physical style spyglass

Functional style

Materials: brass, glass

Drawtube data:

Drawtube notes:

Diameter: 42 mm

Objective Data

Eyepieces

Notes: