First Telephone Conversation Turns 150

Exactly 150 years ago, on October 9, 1876, telephone inventor Alexander Graham Bell and his assistant Thomas Watson held the first two-way telephone conversation outside a laboratory. The information was published on the Smithsonian Libraries blog.

Before that, they had only been able to speak by telephone from different rooms in the same laboratory. During the historic conversation, Bell was at the office of Walworth Manufacturing in Boston, while Watson was in nearby Cambridge. Instead of installing a new telephone line for the experiment, they used an existing telegraph wire connecting the company’s office with its factory.

The conversation lasted nearly three hours. Bell and Watson each wrote down the words they heard on their side. These notes were later made public together. The historic event is also commemorated by a plaque installed in Cambridgeport in 1961.

Bell had received a patent for his telephone invention on March 7 of that year. He submitted the patent application on February 14. On the same day, another inventor, Elisha Gray, also filed a preliminary application for a similar device.

On March 10, 1876, Bell successfully transmitted the human voice by telephone for the first time. He told his assistant Thomas Watson: “Mr. Watson, come here! I want to see you!” These words later became known as the first words spoken over the telephone.

On August 10, Bell also tested telephone communication between the Canadian cities of Brantford and Paris. However, that experiment was not a two-way conversation.

On October 9, another major step was made in telephone history: Bell and Watson were able to speak freely with each other by telephone between two cities outside the laboratory.