HELIOGRAPH (from Gr. riXLos, sun, and ypackly to write), an instrument for reflecting the rays of the sun (or the light obtained from any other source) over a considerable distance. Its main application is in military signalling (see SIGNAL). A similar instrument is the heliotrope, used principally for defining distant points in geodetic surveys, such as in the triangulation of India, and in the verification of the African arc of the meridian. It is necessary to distinguish the method of signalling termed heliography from the photographic process of the same name (see PHOTOGRAPHY).
b
End of Article: HELIOGRAPH (from Gr. riXLos, sun, and ypackly to write) |
|
[back] HELIOGABALUS (ELAGABALUS) |
[next] HELIOMETER (from Gr. iXtos, sun, and p.Erpov, a mea... |
There are no comments yet for this article.
Do not copy, download, transfer, or otherwise replicate the site content in whole or in part.
Links to articles and home page are encouraged.