On This Day in Telephone History June 2ND 1875 Twang of reed transmitted over harmonic telegraph wire confirmed Alexander Graham Bell‘s speech transmission theory.
This event occurred at the Charles Williams, Jr.’s, shop, 109 Court Street, Boston.
“I had charge of the transmitters as usual, setting them squealing one after the other, while Bell was re-tuning the receiver springs one by one, pressing them against his ear. . . . One of the transmitter springs I was attending to stopped vibrating and I plucked it to start it again. It didn’t start and I kept on plucking it, when suddenly I heard a shout from Bell in the next room, and then out he came with a rush, demanding: ‘What did you do then? Don’t change anything! Let me see?’ I showed him. It was very simple.” – Thomas Watson