Visual spectroscope
Title
Visual spectroscope
Subject
Astronomy
Measuring instrument
Optical instrument
Spectroscope
Measuring instrument
Optical instrument
Spectroscope
Description
Wood, brass, glass
Comes with large wooden box with hinged lid (24” x 14” x 8”), 12”tall stand (obs 726), and accessories. It includes a dense flint prism and a reflection diffraction grating. Crosshairs and a precise scale permit the measurement of position of the emission or absorption lines to an accuracy of 6.5 Angstroms with the prism and 3 Angstroms with the diffraction grating. Slow motion arm is damaged, soldering makes attaching to the stand difficult.
In Stebbins’ notebook, “One second size astronomical spectroscope with circle and slow motions, one 1-inch grating, one dense flint prism with minimum deviation, without micrometer. Final bill June 29 $200.”
“The curves are based upon the normal solar spectrum produced by a small grating spectroscope attached to the 12-inch refractor. The center of the sun’s image was kept on the slit of the spectroscope, . . . The spectroscope is a modest affair, being next to the smallest size regularly manufactured by Brashear. The ruled surface of the plane grating is 19 x 25 mm and the objectives of the collimator and view telescope are each of 19 mm aperture and 285 mm focal length.”
Cleaned by J.W. Fecker in 1954.
Comes with large wooden box with hinged lid (24” x 14” x 8”), 12”tall stand (obs 726), and accessories. It includes a dense flint prism and a reflection diffraction grating. Crosshairs and a precise scale permit the measurement of position of the emission or absorption lines to an accuracy of 6.5 Angstroms with the prism and 3 Angstroms with the diffraction grating. Slow motion arm is damaged, soldering makes attaching to the stand difficult.
In Stebbins’ notebook, “One second size astronomical spectroscope with circle and slow motions, one 1-inch grating, one dense flint prism with minimum deviation, without micrometer. Final bill June 29 $200.”
“The curves are based upon the normal solar spectrum produced by a small grating spectroscope attached to the 12-inch refractor. The center of the sun’s image was kept on the slit of the spectroscope, . . . The spectroscope is a modest affair, being next to the smallest size regularly manufactured by Brashear. The ruled surface of the plane grating is 19 x 25 mm and the objectives of the collimator and view telescope are each of 19 mm aperture and 285 mm focal length.”
Cleaned by J.W. Fecker in 1954.
Creator
John Brashear, Pittsburgh
Source
Stebbins, J. 1907. The color sensibility of selenium cells. Astrophysical Journal. 26, 326, 183-187.
John A. Brashear Company LTD. (1906). Catalogue: Optical, physical, astrophysical and astronomical instruments. John A. Brashear Co. LTD.: Allegheny PA.
John A. Brashear Company LTD. (1906). Catalogue: Optical, physical, astrophysical and astronomical instruments. John A. Brashear Co. LTD.: Allegheny PA.
Publisher
Astronomy Department, University of Illinois, Urbana, Illinois
Date
1907
Contributor
Michael Svec
Rights
copyright by Michael Svec.
Format
image/jpg
Language
English
Type
physical object
Identifier
University of Illinois Observatory Collection A132
University ID 016671, obs67
University ID 016671, obs67
Coverage
University of Illinois Observatory, Urbana, Illinois
Files
Collection
Citation
John Brashear, Pittsburgh, “Visual spectroscope,” University of Illinois Observatory Collection, accessed March 28, 2024, https://uiobservatory.omeka.net/items/show/5.