The expanses of the music stretch out broad and sequential, the climaxes unfold deliberately, gather force and body like a rising sea. Look through the long, complex development section of the Allegro of the Second Symphony, and note its fine economy of means, its surprising grandeur of effect; see how two or three motifs are made to flower out into the most luxuriant forms, and how a page can be educed from a measure. This is what is meant by thematic development, which no man thoroughly understood before Beethoven. This insistent coherence and sequaciousness is kept from becoming tiresome or monotonous by the variety of the themes themselves and of the modes adopted for developing them. Indeed, so consummately is the fundamental progressiveness hidden under a variegated and ever-changing surface that the casual observer is apt to be impressed chiefly by the sudden novelties of effect, the unexpected alternations of loud and soft, the collocation of contrasted rhythms, the prominence given to distant tonalities by modulation, in Beethoven’s work, and to realize its solidity and balance only after a more careful study. Rhythmical variety alone in Beethoven is so perpetual and so ingenious that a large treatise would hardly suffice to describe it. Short, nervous phrases of half-a-measure length alternate with wide expanses where for four or more measures there is not so much as a comma.[40] Motifs longer or shorter than the measure are so adjusted as to make up considerable passages in which the accent constantly changes.[41] Diminutions and augmentations of motifs are deftly used.[42] In ways too numerous to mention Beethoven introduces life into his work by constant variation of rhythmic grouping.