Accession No

2571

Brief Description

flat telescope mirror for William Lassell's 40-ft telescope, by William Lassell, English, 1860 (c)

Origin

England

Maker

Lassell, William

Class

optical; astronomy

Earliest Date

1860

Latest Date

1860

Inscription Date

1875

Material

metal (speculum metal, tin); wood; cloth (cotton wool)

Dimensions

box length 187mm; breadth 143mm; height 42mm

Special Collection

Provenance

Transferred from Institute of Astronomy, University of Cambridge, Cambridge, England, 5/6/1980. Found at Cambridge University Institute of Astronomy, 1980. Flat for Lassell’s 4ft equatorial.

Inscription

‘B’ (on back of mirror)
‘B’ (on back of mirror)
‘B’ (on lid of box)
‘B’ (on tin plate in box)
‘Plane Speculum B Polished on Machine, 9 July 1875.
Examined 10th on usual tests...’ (etc., label inside lid of box)

Description Notes

Elliptical flat for Newtonian reflecting telescope (Lassell’s 40ft) speculum metal. Packed with wood, cotton wool and tin (?) (2 plates) in fitted tin (?) box.

References

Events