secutively, which has already been described in connection with Scarlatti's work. Thus in a Sonata in D major for Violin and Pianoforte, the first section of the first movement may be divided into seven distinct passages, each of which is severally repeated in some form or other consecutively. There are some peculiarities, such as the introduction of a new subject in the working-out portion of the work, instead of keeping consistently to development of the principal ideas; and the filling of the episodes of a rondo with a variety of different ideas, severally distinct; but as these points are not the precursors of further development, they are hardly worth discussing. It only requires to be pointed out that occasionally in pianoforte and other sonatas he makes experiments in novel distribution and entirely original manipulation of the structural elements of binary and other forms; which is sufficient to prove not only that he recognised the fitness of other outlines besides those that he generally adopted, but that he was capable of adapting himself to novel situations, if there had been any call for effort in that direction. As it happened, the circumstances both of musical and social life were unique, and he was enabled to satisfy the highest critical taste of his day without the effort of finding a new point of departure.
His treatment of rondo-form is different and less elementary than Haydn's. Haydn most commonly used a very decisively sectional system, in which every characteristic portion, especially the theme, was marked off distinct and complete. This accorded with the primitive idea of rondos as exemplified, often very happily, in the works of early French composers, and in certain forms of vocal music. The root-idea appears in the most elementary stages of musical intelligence as a distinct verse or tune which forms the staple of the whole matter, and is, for the sake of contrast, interspersed with digressions of subordinate interest. It is so obvious a means of arriving at something like structural balance, that it probably existed in times even before the earliest of which evidence remains. In the earliest specimens to be found in sonatas, the traces of their kinship can be clearly followed. Reference has been already made to the two examples in the sonatas by Paradies, which consist of an aria, a contrasting passage, and then the aria pure and simple again, and so forth. Haydn adopted the same general outline. He frequently begins with a complete theme systematically set out with double bars and repeats, and a full conclusion. He then begins something entirely different either in a new related key, or in the minor of the principal key, and makes a complete whole of that also, and so on right through, alternating his main tune with one or more others all equally complete. Under such circumstances his principle of giving variations at each return of the theme or repetition of an episode is almost indispensable to avoid monotony. Mozart rarely makes any point of this plan of adopting variations in his sonata-rondos, because it is not required. He does not often cast his theme in such extremely distinct outlines. In structure it is more what an ordinary binary subject would be; that is, complete and distinct in itself as an idea, without being so carried out as to make its connection with the rest of the movement a matter of secondary rather than intrinsic consequence. Haydn's conception is perfectly just and rational, but Mozart's is more mature. The theme and its episodes are more closely interwoven, and the development of the whole has a more consistent and uniform texture. Mozart does not avoid varying his theme; on the contrary, he constantly puts in the most delicate strokes of detail, and of graceful adornment, and sometimes resorts to delightfully ready development of its resources; but with him it is not so indispensable, because his conception of the form gives it so much more freedom and elasticity.
The central movement of his three-movement sonatas is almost invariably a slow one, commonly in the key of the subdominant. The style of these is characteristic of the time; that is, rather artificial and full of graces, which require to be given with a somewhat conscious elegance of manner, not altogether consonant with the spirit of later times. They rarely touch the point of feeling expected in modern movements of the kind, because the conception formed of the proper function of the slow movement in his time was clearly alien to that of the 19th century. As specimens of elegance and taste, however, Mozart's examples probably attain the highest point possible in their particular genus.
The technique of his sonatas, from the point of view of instrumental resource, is richer and fuller than Haydn's, but still thin and rather empty in sound to ears that are accustomed to the wonderful development of the resources of the modern pianoforte; but the refinement and self-containment of his style make him particularly acceptable to artists who idealise finish and elegance in solo performance, and nicety of ensemble in works for combined instruments, as the highest and most indispensable condition of art. His instinct for adapting his thoughts to instrumental idiosyncrasies was of a very high order when the instruments were familiar and properly developed. This with the pianoforte was not yet achieved, and consequently some of his forms of expression are hardly adapted to its nature, and seem in these days to be rather compromises than perfectly suitable utterances.
With regard to the technical matter of the development of the resources of the pianoforte, Mozart's contemporary, Muzio Clementi, occupies a most important position. Clementi, in his early days, according to his own admission, applied himself rather to the development of the resources of playing than to the matter to be played, and attained a degree and a kind of mastery which no one before his time had heard the like of. When he began to apply himself more to the matter, this study served him in good stead; and his divination of the treatment most appropriate to the instrument, expanded by this means in practical application, marks his
