28
edits
Changes
→Full timeline
| 1816|| Telegraph (Proof of Concept) || Francis Ronalds || <ref name="semaphore">{{cite web |url=http://historyofinformation.com/expanded.php?id=519 |accessdate=December 30, 2017}}</ref>
|-
| 1837|| Telegraph (Electric Relay) || Joseph Henry, Edward davy Davy || <ref name="semaphore">{{cite web |url=https://www.princeton.edu/ssp/joseph-henry-project/telegraph/A_history_of_electric_telegraphy_to_the.pdf |accessdate=December 30, 2017}}</ref>|-| 1840|| Telegraph (Allowed Unskilled Operator) || Charles Wheatstone's || <ref name="semaphore">{{cite web |url=https://en.wikipedia.org/wiki/Cooke_and_Wheatstone_telegraph |accessdate=December 30, 2017}}</ref>
|-
