Heliography

Heliography, a method of signalling from distant points by means of the sun's rays flashed from mirrors; messages can in this manner be transmitted a distance of 190 m.; it has been found of great practical value in military operations.

Definition taken from The Nuttall Encyclopædia, edited by the Reverend James Wood (1907)

Helioga`balus * Heliopolis
Helder, The
Helen
Helena, St.
Helensburgh
Helenus
Heliand
Helicon
Heligoland
Heliodorus
Helioga`balus
Heliography
Heliopolis
Helios
Heliotrope
Hell Fire
Hell Gate
Hellas
Helle
Hellenists
Heller, Stephen
Helmholtz, Hermann von