Beethoven was thoroughly familiar with his piano. The instrument has been further improved since his day. Particularly the lower registers have been given greater sonority, and the instrument as a whole has gained much in sustaining power. Therefore it is inevitable that certain passages which he conceived upon the Broadwood or the Érard of 1820 or earlier are not wholly fitting to the modern piano. This is especially true of passages in the lower registers. The accompaniment to the noble second theme in the first movement of the sonata opus 57 is, for example, unquestionably thick. It is too low and muddy for the present-day piano. Many similar instances might be mentioned, most of which, however, prove only that pianos have changed. His frequent use of close accompaniment figures is perhaps intrinsically old-fashioned; but, on the other hand, wider figures would have been less sonorous on the piano he wrote for than those he used. It is, however, in such matters that Beethoven’s pianoforte music is, from one point of view, not entirely satisfactory to the pianist of today. If in other respects it is at times seemingly orchestral, if successive repetitions of the same phrase seem to tax the pianoforte too far, that does not take from it all as a whole the honor of being one of the greatest contributions to pure pianoforte literature. It was natural that Beethoven’s conception of music as an art akin to poetry, conveying a more or less definite expression, should have great influence upon the forms in which he wrote. The sonata filled up enormously from his inspiration. To begin with, the triplex form took on more and more dramatic life. The development is to be noticed in several ways, some slower to make their appearance than others. Almost at once the contrasting natures of the first and second themes become apparent. Haydn, it will be remembered, often used but a variant of the first theme for the second, much as Emanuel Bach had done; but making his setting of the second theme far clearer. Mozart used distinctly different themes, but both were, as a rule, melodious, different in line but not in nature. On the other hand, the first three sonatas of Beethoven show a complete differentiation of the themes. The second and third are conspicuous and show a procedure in the matter of themes from which Beethoven rarely departed.