Invention of the telephone hardly a commercially practical telephone in the modern sense. Thomas Edison tested the Reis equipment and found that "single words, uttered as in reading, speaking and the like, were perceptible indistinctly, notwithstanding here also the inflections of the voice, the modulations of interrogation, wonder, command, etc., attained distinct expression." In 1947, the Reis device was tested by the British company Standard Telephones and Cables (STC). The results also confirmed it could transmit and receive speech with good quality (fidelity), but relatively low intensity. At the time STC was bidding for a contract with Alexander Graham Bell's American Telephone and Telegraph
Invention of the telephone in the art of instructing the deaf how to speak and experimented with the Leon Scott phonautograph in recording the vibrations of speech. This apparatus consists essentially of a thin membrane vibrated by the voice and carrying a light-weight stylus, which traces an undulatory line on a plate of smoked glass. The line is a graphic representation of the vibrations of the membrane and the waves of sound in the air. This background prepared Bell for work with spoken sound waves and electricity. He began his experiments in 1873-1874 with a harmonic telegraph, following the examples of Bourseul, Reis, and