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heliography (s) (noun), heliographies (pl)
1. The use of a signaling device that uses flashes of sunlight: Two mirrors reflect heliographies of sunlight on a distant point through a shutter so that messages may be transmitted in telegraphic code.
2. A process where an instrument records the amount and duration of sunshine, often on a strip of blueprint paper.
This entry is located in the following units: grapho-, graph-, -graph, -graphy, -grapher, -graphia (page 43) helio-, heli- (page 2)