Researched
Optical Telegraph (Chappe)
Claude Chappe's semaphore towers (1792) relay coded signals by telescope from hilltop to hilltop: the first national message network.
Open in the interactive tree →France's first line ran from Paris to Lille in 1794, passing a message in minutes instead of a day. The system of relay stations, codebooks and operators prefigured electric telegraph networks.
Prerequisites
- The telescope1608
Unlocks
- Electric Telegraph1844Chappe's relay-station network was the first working model of a telegraph network