Steinheil: The Man Who Fired the Second Wire Every early telegraph needed two wires, and copper was the budget. This guide explains Steinheil's 1837 discovery that the earth itself completes the circuit - halving the cost of every line on Earth. Quick facts Discoverer C. A. von Steinheil Year 1837 Method earth plates, one wire Saving half the copper Also his printing telegraph The earth-return discovery made the 1840s telegraph boom affordable, and its ghost survives in every radio station's ground system. Steinheil - astronomer and lens designer too - may be the most under-credited man in the telegraph story. Give it a go: https://morsecodeworks.com/ Morse Code Works - free Morse code tools and guides. Reference chart