Portable telescope

This non-achromatic telescope has seven draw tubes made of paper covered in vellum, while the barrel is covered in multi-coloured vellum and further decorated with gold tooling. The lenses are set in turned ebony mounts.

A hand-written inscription on the largest draw tube states that it belonged to the Rev. Ralph Taylor, who went into exile with King James II (reigned 1685-88) and later lived in Rotterdam. The inscription also says that the telescope is probably Italian, although it is English in style.

Early telescope lenses suffered from the appearance of coloured fringes, a problem that could be reduced by using lenses with long focal lengths. This meant, however, that the telescopes had to be very long - this telescope can be extended to over two metres in length.

Object Details

ID: NAV1490
Collection: Astronomical and navigational instruments
Type: Portable telescope
Display location: Not on display
Creator: Unknown
Date made: circa 1690
Credit: National Maritime Museum, Greenwich, London
Measurements: Length: 503 mm (closed), 1649 mm (open to stop lines); Diameter 69 mm (barrel)