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)