Sujet
Heliograph, a visual telegraph
Légende
Heliograph, a visual telegraph for sending and receiving messages by means of mirrors and sunlight. Here a British signal unit in tropical kit are sending a message to the fort in the distance. Liebig trade card c.1900. Chromolithograph
Date
20e siècle
Crédit
Photo12/Ann Ronan Picture Library
Notre référence
ARP07102_390006041
Licence
Droits gérés
Format disponible
24.2Mo (1.9Mo) / 30.0cm x 20.2cm / 3543 x 2383 (300dpi)