THE PLAYER PIANO The player piano may not necessarily be considered a robot, it is however, a fine example of an early machine that possesses the ability to be "reprogrammed" to operate independently with a myriad of variations. It became popular in the early 1900s as a mechanism designed to read music for the piano without the need of a trained pianist. The music is read from interchangeable rolls of paper with many tiny perforations throughout. During a performance on the player piano the 'pianolist' can change the dynamics, accentuation and tempo of the piece through the use of foot pedals and levers. At the bottom of the piano are two pedals which power the player apparatus through the use of suction. As the music roll is unreeled the tiny holes pass over corresponding tubes, each one leading to a small hammer inside the piano. These tubes contain enclosed vacuums which are then broken when a hole passes over it. This causes an increase in pressure inside the player mechanism which causes a particular hammer to strike a string thus producing sound.