Accession No
1479
Brief Description
solar spectroscope, by Adam Hilger Ltd., English, 1921
Origin
England; London
Maker
Adam Hilger Ltd.
Class
optical
Earliest Date
1921
Latest Date
1921
Inscription Date
Material
metal; brass; steel; glass; aluminium
Dimensions
overall length 320mm
Special Collection
Provenance
Donated in 12/1970.
Inscription
‘AH
LTD’ (above slit)
‘SCREW = 1/60’ (below slit)
‘ADAM HILGER LTD.
LONDON, ENGLAND.
NOG.24.301/21204’ (aluminium casing)
Description Notes
Evershed 2-prism solar spectroscope (solar prominence spectroscope). Aluminium, brass and steel. Steel slit, adjustable by micrometer screw, drumhead divided 0 - [100], numbered by 10, graduated to 1. Sliding stop for slit. Brass collimator. Two composite prisms and mirror housed in aluminium casing. Micrometer screw for rotating mirror with steel drumhead divided 0 - [100], numbered by 10, graduated to 1, moving across linear scale divided 0 - [25], numbered by 10, graduated to 1. Brass telescope with rack and pinion focus. Brass spiggot beneath case, presumably for mounting.
Good condition.
References
Events
Description
Spectroscope
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:40375
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