The sonatas themselves bear this out. The eight which we have been able to study, are light stuff, indisputably. But the triplex form is clear in most of the movements. He uses two separate distinct melodies as themes. The first appears at once in the tonic, the second later in the dominant. The first section, which is nothing more than the exposition of these two themes, is repeated. After the double bar follows a section of varying length, usually dominated by reminiscences of the first theme, the modulations of which are free but by no means unusual. Then the third section repeats both melodies in the tonic key. The first movement of a sonata in G major is conspicuous for the length of its second section, in which there is not only a good bit of interesting modulation, but also actually new material.

The bass which bears his name is no more than the familiar breaking of a chord in the following manner:

[PNG][[audio/mpeg]]

It is hardly more true that he invented it than that such a formula is intrinsically as contemptible as many musicians, mostly theoreticians, would make it out to be. If a musician is, in a given composition, concerned with melody, he may be justified in following the procedure which makes that melody reign undisputed over his music. This inevitably will reduce the accompaniment to the simplest function possible; namely, outlining or supplying the harmony upon which all melodies, since the Middle Ages at least, have been felt to rest.

In the first sophisticated experiments with melody—the opera early in the seventeenth century—the accompaniment to a song was frequently no more than a few occasional chords upon the harpsichord. These chords were not even written out for the accompanist, but were indicated to him by figures placed over the notes of a single bass part. As composers acquired skill in combining several instruments in accompaniments to their operas, the figured bass lost its importance; but it was still employed as a sort of harmonic groundwork almost to the end of the eighteenth century. It was a prop to the harmonies woven more or less contrapuntally by other instruments, which, unlike the harpsichord, had power to sustain tone.

Harpsichord composers. From top left to bottom right:
D. Scarlatti, Couperin, C. P. E. Bach, Clementi.

When a man like Alberti at last endeavored to write purely melodic music on the harpsichord alone, which by the way was wholly unfitted to sing, three methods of accompaniment were open to him. One of these was to give to the left hand, as accompanist, a counter-melody or counter-melodies, which, interweaving with the upper melody, would create harmonic progressions. Allowing him to have had the skill to do this, as Couperin or Bach had been able to do, it would not have recommended itself to him as the best way to set off the chief melody. Such a procedure inevitably tangled melody with accompaniment. Secondly, he could give to the left hand a series of chords. But owing to the nature of the harpsichord, these would sound dry and detached, with cold harmonic vacancies between; unless he chose to repeat the chords rapidly, which process was decidedly clumsy. Finally he could break up the chords into their separate notes, combine these in groups easily within the grasp of the hand, and by playing these groups rapidly over and over again, produce a constantly moving harmonic current on which his melody might float along. This is in fact what Alberti did, and this is the legitimate function of the Alberti bass, one which can no more be dispensed with from pianoforte music than the tremolo from the orchestra.

It is hardly possible to believe that he invented the particular formula which plays such a part in his music. Bach had devised many methods of breaking chords so that their component parts might be kept in rapid and constant vibration. Witness alone the first and second preludes in the first book of the ‘Well-tempered Clavichord.’ In the ninth toccata of the elder Scarlatti there is an eight-measure passage of chords broken exactly in the Alberti manner. But such devices were employed by Bach and likewise by A. Scarlatti in passages of purely harmonic significance. Alberti must be among the first, if he is not actually the first, to use them to supply a simple harmonic basis for his melodies.