Accession No
2839
Brief Description
spectroscope, by W. Watson and Sons Ltd., English, 1900 (c)
Origin
England; London
Maker
W. Watson and Sons Ltd.
Class
optical
Earliest Date
1900
Latest Date
1900
Inscription Date
Material
metal (brass, steel); glass; cloth (velvet)
Dimensions
box length 123mm; breadth 80mm; height 32mm
Special Collection
Provenance
Purchased from Christie’s, South Kensington, London, England; lot 222, 29/04/1982.
Inscription
‘W. Watson & Sons. Ltd
London.
10740’
Description Notes
Brass direct-vision spectroscope. Glazed cover for slit. Slit with steel jaws, width adjustable by knurled ring. Brass barrel with screw-in eyepiece. Subsidiary brass tube, also with glazed cover, with micrometer scale reflected into field of view. Slit on long push-fit draw tube. Crimson velvet-lined fitted box.
References
Events
Description
In 1814, Joseph von Fraunhofer noticed that the sun’s spectrum, when dispersed by a glass prism, is crossed by hundreds of fine dark lines. These lines could be used to determine the chemical composition of the sun, stars, and many other substances by spectral analysis. The first photograph of the spectrum of a star (Vega) was made by Henry Draper using a spectroscope in 1872.
There are various different forms of spectroscope, but all use a slit and collimator to make a parallel beam of light, a prism for dispersing different wavelengths, and a telescope to observe the dispersed spectrum.
18/10/2002
Created by: Saffron Clackson on 18/10/2002
FM:44867
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