The formation of the Bell Telephone Company superseded an agreement between Alexander Graham Bell and his financiers, principal among them Gardiner Greene Hubbard and Thomas Sanders. Renamed the National Bell Telephone Company in March 1879, it became the American Bell Telephone Company in March 1880.
In 1880, the management of American Bell created what would become AT&T Long Lines. The project was the first of its kind to create a nationwide long-distance network with a commercially viable cost structure. This project was formally incorporated into a separate company christened American Telephone and Telegraph Company on March 3, 1885. Starting from New York, the network reached Chicago, Illinois in 1892.
On December 30, 1899, the American Telephone and Telegraph Company bought the assets of American Bell; this was because Massachusetts corporate laws were very restrictive, and limited capitalization to ten million dollars, forestalling the growth of American Bell itself.
LINK: Cartography Associates, David Rumsey Collection.