Work of the organ schools of Venice and Rome--Polyphonic playing and the advent of the singing style--Scale playing and the use of the thumb--Bach's fingering and Mozart's vocal playing--Development of tone-color--Pedalling and variety of touch--Chopin, Schumann, and Liszt technics. The origin of piano music, and, indeed, of much of the entire mass of modern instrumental music, was the organ compositions of the early masters. The early clavichords were used almost exclusively for the home practice of organists; and even after it became fashionable for young ladies to learn the art of playing, there was no difference whatever between the style of music written for the organ and of that composed for the clavichord, nor in the manner of playing either instrument. Every musician knows that in our time the kind of touch used for the organ is essentially different from that used for the piano, and that music suitable for one instrument is not suitable for the other. But it was not thus in the earliest days; for the only professional pianists (or clavichordists, to be more precise) were the organists, and instrumental music had not yet reached a state of development high enough to produce a divergence of styles. The fact that the same keyboard was used in both instruments was sufficient to suggest to the early organists that one style of playing was practicable for both. It naturally did not occur to them to write different sorts of music; and it is necessary, therefore, for us to inquire what was the nature of the early organ music.