One knows that the kind of _Concerti Grossi_, which consists chiefly in a dialogue between a group of solo instrumentalists (the _Concertino_) and the full body of instruments (_Concerto Grosso_), to which is added the cembalo,[407] was, if not invented, at least carried to its perfection and rendered classical by Corelli.[408] The works of Corelli, aided by the efforts of his followers, had become widely known in Europe. Geminiani introduced them into England,[409] and without doubt Handel did not hesitate to profit by the example of Geminiani, who was his friend;[410] but it is much more natural to think that he learnt the _Concerto Grosso_, at its source at Rome, from Corelli himself during his sojourn there in 1708. Several of his Concertos in his Opus 3[411] date from 1710, 1716, 1722. The same feature shows itself right up to the time of his apprenticeship at Hamburg: in any case he might have already known the Corellian style, thanks to the propaganda of George Muffat, who spread this style very early in Germany.[412] After Corelli, Locatelli,[413] and especially Vivaldi,[414] have singularly transformed the _Concerto Grosso_ by giving it the free character of programme music[415] and by turning it resolutely towards the form of the Sonata in three parts. But when the works of Vivaldi were played in London in 1723, and the works which aroused such a general enthusiasm became thoroughly known to Handel, it was always to Corelli that he gave the preference, and he was very conservative in certain ways even about him. The form of his Concerto, of which the principal movements varied from four to six, oscillated between the Suite and the Sonata, and even glanced towards the symphonic overture. It is this for which the theorists blame him, and it is this for which I praise him. For he does not seek to impose a uniform cast on his thoughts, but leaves it open to himself to fashion the form as he requires, and the framework varies accordingly, following his inclinations from day to day. The spontaneity of his thought, which has already been shown by the extreme rapidity with which the _Concerti_ were composed--each in a single day at a single sitting, and many each week[416]--constitutes the great charm of these works. They are, in the words of Kretzschmar, grand impression pictures, translated into a form, at the same time precise and supple, in which the least change of emotion can make itself easily felt. Truly they are not all of equal value. Their conception itself, which depended in a way on mere momentary inspiration, is the explanation of this extreme inequality. One ought to acknowledge here that the Seventh Concerto, for example (the one in B flat major), and the last three have but a moderate interest.[417] They are amongst those least played; but to be quite just we must pay homage to these masterpieces, and especially to the Second Concerto in F major, which is like a