The Telephone

On March 10, 1876, Bell spoke into his telephone to test his invention. A telephone transmitter turned sound waves from his voice into electric currents. The currents traveled down the wire toward the telephone receiver, which Watson was holding in another room. The receiver turned the electric currents back into sound waves, which traveled to Watson’s ear. Watson could hear Bell’s voice!

Bell brought his invention to the 1876 World’s Fair, in Philadelphia, Pennsylvania. It was a success. Two years later, President Rutherford B. Hayes had his own telephone! In 1877, Bell helped form the Bell Telephone Company. It would grow into one of the largest companies in the United States.

Bell showed this improved version of his telephone transmitter at the 1876 World’s Fair.View Larger Image

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