Word Study
spectroheliograph
CIDE DICTIONARY
spectroheliograph, n.
An apparatus for making spectroheliograms, consisting of a spectroscopic camera used in combination with a telescope, and provided with clockwork for moving the sun's image across the slit. [Webster 1913 Suppl.]
OXFORD DICTIONARY
spectroheliograph, n. an instrument for taking photographs of the sun in the light of one wavelength only.
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