tutor during his time at the School of Jurisprudence. Added to what he learned at the Saint Petersburg Conservatory studies, this talent allowed Tchaikovsky to employ a varied range of harmony in his music, from the Western harmonic and textural practices of his first two string quartets to the use of the whole-tone scale in the center of the finale of the Second Symphony, a practice more typically used by The Five. Rhythm Rhythmically, Tchaikovsky sometimes experimented with unusual meters. More often, he used a firm, regular meter, a practice that served him well in dance music. At times, his rhythms became pronounced enough to become the main expressive agent of the music. They also became a means, found typically in Russian folk music, of simulating movement or progression in large-scale symphonic movements—a "synthetic propulsion", as Brown phrases it, which substituted for the momentum that would be created in strict sonata form by the interaction of melodic or motivic elements. This interaction generally does not take place in Russian music. (For more on this, please see Repetition below.) Structure Tchaikovsky struggled with sonata form. Its principle of organic growth through the interplay of musical themes was alien to Russian practice. The traditional argument that Tchaikovsky seemed unable to develop themes in this manner fails to consider this point; it also discounts the possibility that Tchaikovsky might have intended the development passages in his large-scale works to act as "enforced hiatuses" to build tension, rather than grow organically as smoothly progressive musical arguments. According to Brown and musicologists Hans Keller and Daniel Zhitomirsky, Tchaikovsky found his solution to large-scale structure while composing the Fourth Symphony. He essentially sidestepped thematic interaction and kept sonata form only as an "outline", as Zhitomirsky phrases it. Within this outline, the focus centered on periodic alternation and juxtaposition. Tchaikovsky placed blocks of dissimilar tonal and thematic material alongside one another, with what Keller calls "new and violent contrasts" between musical themes, keys, and harmonies. This process, according to Brown and Keller, builds momentum and adds intense drama. While the result, Warrack charges, is still "an ingenious episodic treatment of two tunes rather than a symphonic development of them" in the Germanic sense, Brown counters that it took the listener of the period "through a succession of often highly charged sections which added up to a radically new kind of symphonic experience" (italics Brown), one that functioned