Telegraph flag system. 19th-century book page showing signals and codes transmitted by use of flag telegraphy or semaphore signals. This page shows a compass flag at top,with seven pennants below. Below this is a key used to encode private communications,with a decoding explanation at bottom. Such systems were used between ships until replaced by wireless telegraphy (radio). This page is from the second edition (1818) of 'An Improved System of Telegraphic Communication' by British naval officer Thomas Lynn (1774-1847) | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / King's College London |
Bildgröße: | 3367 px × 5239 px |
Modell-Rechte: | nicht erforderlich |
Eigentums-Rechte: | nicht erforderlich |
Restrictions: | - |