heliography

Century Dictionary and Cyclopedia

1. n. A method of signaling between distant points by means of the heliograph.
2. n. In general, photography; specifically, some special photographic process; photographic engraving. See the extract, and heliographic engraving, under heliographic.
3. n. The description and mapping of the surface of the sun.

Wiktionary

1. n. The scientific study of the sun
2. n. The art of making a heliograph
3. n. The system of signalling by heliograph

GNU Webster's 1913

1. n. The description of the sun.
2. n. The system, art, or practice of telegraphing, or signaling, with the heliograph.
3. n. An early photographic process invented by Nicéphore Niepce, and still used in photo-engraving. It consists essentially in exposing under a design or in a camera a polished metal plate coated with a preparation of asphalt, and subsequently treating the plate with a suitable solvent. The light renders insoluble those parts of the film which is strikes, and so a permanent image is formed, which can be etched upon the plate by the use of acid.
4. n. Archaic. Photography.