Mirror of speculum metal in tin cell

Made:
1780-1820 in England
maker:
William Herschel

Nine inch mirror of speculum metal (exact diam" 8 15/16 in) in tin cell with close fitting cover 9 1/2" diam, 1 1/2" deep, focal length 10' 1", cell and cover each painted " J"

Details

Category:
Astronomy
Object Number:
1925-464
Materials:
speculum metal and tin
type:
components, concave mirrors, metal mirrors and astronomical instruments
credit:
Mr John Herschel-Shorland

Parts

Nine inch mirror of speculum metal (exact diam" 8 15/16 in) in tinplate circular case

Mirror of speculum metal in tinplate circular case

Nine inch mirror of speculum metal (exact diam" 8 15/16 in) in tinplate circular case

Measurements:
overall (estimate): 25 x 235 mm
Materials:
speculum , iron , leather and complete
Object Number:
1925-464 Pt1
type:
components , concave mirrors and metal mirrors
Close fitting lid, painted " J" for tinplate circular box containing nine inch speculum mirror.

Close fitting lid

Close fitting lid, painted " J" for tinplate circular box containing nine inch speculum mirror.

Measurements:
overall: 10 x 235 mm
Materials:
iron and complete
Object Number:
1925-464 Pt2
type:
components , storage boxes , lids and instruments

Related Objects

Two plane speculums by Lassell, with Lassell's M.S. directions

Two plane speculums by Lassell

Film positive Nebula N.G.C. 3115
Transparency, 40"x51 1/2", of Crab Nebula in Taurus (M.1. N.G.C. 1952) photographed in red light by the 200-inch Hale telescope

Transparency, 40"x51 1/2"
Transparency, 15"x12", Modern Astronomers (from photo taken at Royal Observatory)

Transparency, 15"x12", Modern Astronomers (from photo taken at Royal Observatory)

Three photographic prints belonging to Horace Dall
Transparency, 40"x51 1/2", of Spiral galaxy in Pegasus, N.G.C. 7217, photographed by the 200-inch Hale telescope

Transparency, 40"x51 1/2"