The device known as the Telephone or the Sound Telegraph, as described in the parchment papers, was a small instrument that was designed for simultaneous transmitting and receiving human voice instead of codes in a telegram.
The telephone was economical and very simple to operate. It consisted of a power source, a circular dialer, a ringer, a transmitter, and a receiver.
The reason why it was inexpensive and easy to use was that the infrastructure had already been laid by the earlier invention of telegraphs beforehand.
The telephone could use the same network cables that have been set up for telegraphs to transmit codes and send signals through them. Only a few newer cables needed to be implemented.
However, Bryan realized that with the limitations of the design on these parchment papers, the telephone could only be used within cities.