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| 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>
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| 1837|| Telegraph (Electric Relay) || Joseph Henry, Edward 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>
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