It is true that Schumann experimented with sympathetic vibrations and overtones, that the player who would give to Chopin its special charm must have an ear tuned to after-sounds, and that Liszt experimented with many similar effects and really opened the way for a treatment of the pianoforte such as that Debussy and Ravel have perfected. But all earlier experiments were limited by a clear perception of certain harmonic proprieties. A chord was defined by the notes struck in it. But in this music of Debussy and Ravel a chord is not such a restricted thing. It is a potentiality rather than an actuality. It spreads and grows in after-sounds so that its boundaries become vague and merge with other boundaries or cross them. So they have created a pianoforte music that seems almost to have no dependence upon the mechanical levers and hammers, a sort of music liberated from the box, and yet the most subtly and intimately related to the instrument that has been written. Debussy’s music is by no means all compact of these vague effects. It is often as clear-cut as crystal, having a _netteté_ hard to match in other music for the instrument. Witness for example _Les jardins sous la pluie_ and _La sérénade interrompue_. In these cases it is plain to see that he is no less aware of the charm latent in the percussive quality of tone in the pianoforte than of that in its peculiar after-sounds. He can be incisive, also, and sharply rhythmical as in _La puerta del Vino_, or sparkling as in the _Feux d’artifice_. Technically, then, Debussy’s pianoforte style seems to have been influenced by a clear perception of the two qualities of sound of which the instrument is capable, and so remarkable has been his revelation of them that one cannot but feel that they come to our ears as fresh discoveries. His ingenuity seems inexhaustible and always successful. He can be rapid without being sensational, forceful without pounding. Except that an occasional use of chords suggests the organ or some new mysterious wind instrument, his music never departs from the piano, to the spirit of which it gives a new expression. It is extremely difficult to play. It requires the utmost fleetness and lightness of fingers; and also a perfect freedom of the arm, for he seems at times to ask the player to touch all parts of the piano at once. In a measure, however, it may be said of some of his music that it conforms to types as Liszt’s does, and that consequently, compared with Bach and Chopin, it is not so difficult. Nevertheless, by all tokens the music of Debussy, though technically it springs from Liszt, is going to elude the grasp of most fingers even as that of Chopin does. Perhaps it is a spiritual rather than a technical difficulty that stands in the way.