II
If, with a view to getting a more precise notion of the new tendencies, we ask ourselves now what are the salient differences between a classical and a romantic or modern piece of music, we shall be likely to notice at once certain traits of the latter, striking enough, which are nevertheless incidental rather than essential to romanticism, and must be discounted before we can come at its inmost nature. These changes have come chiefly as a result of the general evolution of musical resources, and though necessarily modifying the romantic methods, are not primary causes or effects of them. Thus, for example, the nineteenth century has seen an extraordinary development in the mechanism of all musical instruments, and in the skilful use of them by musicians. This is impressed upon us by the most cursory glance at any modern orchestral score. Haydn's and Mozart's orchestra consisted of a nucleus of strings, with a few pairs of wood and brass wind instruments added casually for solos or to reinforce certain voices in the harmonic tissue. The scheme was fundamentally monochromatic, however much it might be set off by bits of color here and there. By the time of Wagner the orchestra was essentially a group of several orchestras of divers colors: the addition of a third flute, of English horn to the oboe family, of bass clarinet, and of contrafagotto made each group of the wood-wind instruments capable of fairly complete harmony; the horns were increased in number from two to six or eight, the bass trumpet made possible complete chords for the trumpets, and there were four trombones and a choir of tubas. Thus, instead of having a uniform foundation, with variety merely in the trimming, the modern orchestra has complete, independent choirs of most various instruments, capable of all sorts of combination, opposition, and contrast.
The manner of writing for the orchestra changed as much as its constitution. Beethoven usually writes three- or four-part harmony for the strings, and doubles the wood and brass as seems effective. Tschaïkowsky and Wagner are apt to put an entire family of instruments on one melodic voice, another on another, a third on a third—as in the second movement of the "Symphonie Pathétique," at the point where flutes, oboes, clarinets, and bassoons sing the melody, while first and second violins and violas pick an obligato to it. In a word, much more attention is paid in the modern orchestra to richness and variety of tone-color and to an impressionistically effective disposition of the various timbres than in the classical scores.
The same tendency is observable in chamber and pianoforte music. Not only are modern composers fond of curious groupings of wind and string instruments, as in the trumpet septet of Saint-Saëns, the clarinet quintet and horn trio of Brahms, and other such works, but when they use only the four stringed instruments they combine contrasting rhythms and modes of phrasing, as well as pizzicato, the sordino, the high register of the 'cello, and other exotic devices, with an unfailing sense of color-values. Schubert is the first conspicuous example of this sort of quartet writing; Dvořák is his worthy follower. As for the piano, there is almost as much difference between the piano writing of Beethoven, so often thick, harsh, and lumpish, and the ramifying figuration of Schumann or the wide, clear arpeggiated accompaniments and flowering scale-figures of Chopin as there is between the coloring of Rembrandt and that of Monet.
All this gain in sensuous richness and technical elaboration is, however, to be considered largely as a concomitant rather than a direct result (though to some extent is was that) of the romantic movement. It was primarily merely a phase of that unparalleled material and mechanical progress so characteristic of the nineteenth century. The modern orchestra and the modern pianoforte are simply special examples of the ingenuity of that century in mechanical devices; the genius which turned the clavichord into the piano was the same as that which substituted the propeller for sails, and the electric telegraph for the lumbering mail-coach. But if this modern mechanical genius has indeed brought to the musician priceless gifts, it is still important to remember that perfected mechanisms do not account for romantic music, which might conceivably have existed without them. Instruments alone cannot make music, any more than a steam derrick can build a bridge. If we wish to seize the true spirit of the modern musical art, we must, after all, leave orchestra, and piano, and sensuous value behind, and ascertain to what use composers have turned all these resources, and to what manner of expression, embodied in what kind of forms, they have been spurred by the romantic spirit.