Word Study
oroheliograph
CIDE DICTIONARY
oroheliograph, n. [Gr. 'o`ros mountain + helio- + -graph.].
A camera for obtaining a circular panoramic view of the horizon. The photographic plate is placed horizontally with a vertical lens above. A mirror of peculiar shape reflects light from the entire horizon to the lens, by means of which it is focused upon the plate. [Webster 1913 Suppl.]
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