solar light source
Date1850-1880
Inventory Number2006
ClassificationLight Source
Subject
Attributed to
Louis Jules Duboscq
French, 1817 - 1886
User
Department of Geology and Geography, Harvard University
1890 - 1961
Cultural Region
Place of Origin
Dimensions50.2 x 30.3 x 27.9 cm (19 3/4 x 11 15/16 x 11 in.)
Material
DescriptionLarge circular mirror mounted on a gearing system linked to the drum at the base of the instrument. The gears inside the drum are activated at a distance by means of two rods equipped with Cardan joints (only one joint is showing here, the other one and the rods are missing). The instrument is supported by a heavy tripod stand.
Signedunsigned
FunctionThis is what Duboscq called a "porte-lumière solaire", a light source created by sunlight. This is not a heliostat. The mirror is oriented by hand at a distance with the help of rods attached to Cardan joints and fixed to the base of the instrument. It could have been used with a heliostat though, as a second mirror made to redirect the sunlight coming from the heliostat.
For a representation of this instrument in one of Duboscq's trade catalogue, see the following website.
For a representation of this instrument in one of Duboscq's trade catalogue, see the following website.
ProvenanceFrom the Departement of Geology and Geography (mineralogy), Harvard University.
Louis Jules Duboscq
Date: 1860-1879, 1882-1885
Object number: 1996-1-0669
Louis Jules Duboscq
Date: 1860-1879, 1882-1885
Object number: 1997-1-0687
Louis Jules Duboscq
Date: 1860-1879, 1882-1885
Object number: 1997-1-0688
Louis Jules Duboscq
Date: 1850-1880
Accessories: RAPPORT FAIT A L'ACADEMIE ROYAL SCIENCES SUR UN NOUVEL HELIOSTAT, Presente par M. SILBERMAN aine. (in instrument file folder)
Object number: 2000
See also/See also
