The direct sources of modern music are to be found in the works of Berlioz, Chopin, Liszt, and Wagner. This assertion savors of truism, but, since the achievement of these four masters in the enlargement of harmonic idiom, in diversity of formal evolution, and in intrinsic novelty and profundity of musical sentiment and emotion remains so unalterably the point of departure in modern music, reiteration is unavoidable and essential. It were idle to deny that various figures in musical history have shown prophetic glimpses of the future. Monteverdi's taste for unprepared dissonance and instinct for graphic instrumental effect; the extraordinary anticipation of Liszt's treatment of the diminished seventh chord, and the enharmonic modulations to be found in the music of Sebastian Bach, the presages of later German romanticism discoverable in the works of his ill-fated son Wilhelm Friedemann, constitute convincing details. The romantic ambitions of Lesueur as to program-music found their reflection in the superheated imagination of Berlioz, and the music-drama of Wagner derives as conclusively from _Fidelio_ as from the more conclusively romantic antecedents of _Euryanthe_. But, despite their illuminating quality, these casual outcroppings of modernity do not reverse the axiomatic statement made above. The trend of modern music, then, may be traced first along the path of the pervasive domination of Wagner; second, the lesser but no less tenacious influence of Liszt; it includes the rise of nationalistic schools, the gradual infiltration of eclecticism leading at last to recent quasi-anarchic efforts to expand the technical elements of music. I