Experimental compound speculum mirror of 2 feet diameter

Made:
1840-1845 in Birr
maker:
William Parsons

Experimental compound speculum mirror of 2 feet diameter, made by the 3rd Earl of Rosse. The 9 segments of speculum metal, are held in an alloy of copper and zinc.

Details

Category:
Astronomy
Object Number:
1876-1008
Materials:
base, iron and mirror, speculum metal (bronze alloy)
Measurements:
overall: 85 x 600 mm
type:
components, concave mirrors, metal mirrors and astronomical instruments
credit:
Lord Rosse (5th Earl)