It is in fact by recognizing the possibilities of movement in the arm that Liszt did most to expand pianoforte technique. One finds not only such an interplaying of the arms as that in ‘Mazeppa’ and other of his compositions, but a playing of the arms together in octave passages which leap over broadest distances at lightning speed. Sometimes these passages are centred, or rather based, so to speak, on a fixed point, from and to which the arms shoot out and back, touching a series of notes even more remote from the base, often being expected to cover the distance of nearly two octaves, as in the beginning of the first concerto. There are samples of this difficulty in ‘Mazeppa’; and also of other runs in octaves for both hands, which are full of irregular and wide skips. In the long and extremely rapid tremolos with which his music is filled, it is again the arm which is exerted to new efforts. The last of the études is a study in tremolo for the arm, and so is the first of the Paganini transcriptions. The tremolo, it need hardly be said, is no invention of Liszt’s, but no composer before him demanded either such rapidity in executing it, or such a flexibility of the arm. The tremolo divided between the two hands, as here in this last study, and the rapid alternation of the two hands in the second study, depend still further on the freedom of the arm. It is the arm that is called upon almost ceaselessly in the tenth study; and the famous _Campanella_ in the Paganini series is only a _tour de force_ in a lateral movement of the arm, swinging on the wrist. The series, usually chromatic, of free chords which one finds surging up and down the keyboard, often for both hands, may well paralyze the unpracticed arm; the somewhat bombastic climaxes, in which, _à la_ Thalberg, he makes a huge noise by pounding chords, are a task for the arm. All of the last part of the eleventh étude, _Harmonies du soir_, is a study for the arm. Indeed even the wide arpeggios, running from top to bottom of the keyboard in bolder flight than Thalberg often ventured upon, the rushing scales, in double or single notes, the countless cadenzas and runs for both hands, all of these, which depend upon velocity for their effect, are possible only through the unmodified liberation of the arm. All this movement of the arm over wide distances and at high speed makes possible the broad and sonorous effects which may be said to distinguish his music from that of his predecessors and his contemporaries. It makes possible his thunders and his winds, his lightnings and his rains. Thus he created a sort of grand style which every one must admit to be imposing.