It is not difficult to understand that chamber music originated in the early medieval custom of accompanying banquets with music. Small bodies of instrumental players formed for this purpose soon created a demand for a separate kind of music for their performance, as well as a desire to hear such music. Indeed chamber music, as such, existed before orchestral music, for the old sonatas in four-voiced counterpoint, written _da cantare e sonare_, when performed as instrumental compositions, constituted what we should class to-day as chamber music. But genuine modern chamber music began to take form when the violin began to assert its true position and the correct balance of strings began to be perceived. This, as we have seen, was subsequent to the time of the violin maker Maggini (1581-1631) and previous to that the violinist Corelli (1653-1713). In his labors tending toward the development of the sonata form Corelli wrote real chamber music. His compositions were classed either as "Sonate di Chiesa" or "Sonate da Camera,"--church sonatas or chamber sonatas. The sonatas employed small combinations of instruments in which the violin and the organ were the chief principals, together with lutes and other stringed instruments. Their relation to the development of the sonata form has already been pointed out. The distribution of instruments, as leading toward modern chamber music is what now concerns us. Corelli's first publication in this line was "XII Sonate a tre, due violini e violoncello, col basso per l'organo," opus 1, Rome, 1683. In 1685 (the year of Bach's birth) he published twelve "sonate da camera" for two violins, 'cello, and cembalo. He published other collections, one of which contained sonatas for four violins, violoncello, and bass, two violins and the 'cello playing the principal parts and the other instruments re-enforcing them in the ensemble passages. The successors of Corelli followed his lead and produced many compositions for small collections of instruments, though it must be borne in mind that the idea of formal concerts of chamber music, such as we have now, did not exist then.