Accession No

1837

Brief Description

reflecting telescope, 18"/4" Gregorian, by James Short, English, circa 1760

Origin

England; London

Maker

Short, James

Class

astronomy; optical

Earliest Date

1760

Latest Date

1760

Inscription Date

Material

metal (brass, speculum metal, tin); glass; ivory; wood (mahogany)

Dimensions

box length 705mm; breadth 305mm; height 161mm

Special Collection

Heywood collection

Provenance

Purchased from the Professor Harold Heywood collection under estate duty exemption benefit with the assistance of a Science Museum grant-in-aid.

Inscription

‘JAMES SHORT LONDON 205/1202 = 18’

Description Notes

Reflecting telescope, 18"/4" Gregorian, by James Short, English, circa 1760.

Gregorian reflecting telescope, brass. 18-inch focal length; 4-inch aperture. 610mm-long barrel with friction-tight cover and finder mounted above. Eye-end (not readily removed) holds speculum metal primary mirror (d: 105mm). Brass piece screws into centre when telescope not in use. Otherwise fitted with screw-in eyepiece with screw-on eyestop. Focus by long screw moving secondary speculum metal mirror from eye-end. Barrel mounted on semi-circle - part of altazimuth mount with two slow motions moved by screws with square ivory handles. Knurled brass screw disengages vertical control; another clamps horizontal motion. Pillar stand on folding tripod base with cabriole feet. Alternative eyepiece with screw-on eyestop. Alternative speculum metal secondary mirror with brass mount in fitted tin box. All in fitted mahogany box with trade label of Alexander Wellington, ‘Successor to the late Mr James Search’.

References

Events