The orchestration of John Sebastian Bach was thin despite its elaboration. The strings formed the foundation, according to the prevailing rule, and were written in so many real parts, and when wind instruments appeared, they were also used with an independent polyphony. His contrasts were, for the most part, produced by giving a melody to a simple solo instrument, accompanied only by a bass, while a figured bass indicated the chords to be filled in by the organ or the clavier. It can hardly be said that the greatest of the Bachs advanced the art and science of orchestration. Handel's scoring was in quite another vein, and may be viewed as revolutionary for its era. In his overtures, especially, his strings are used with the evident object of producing solidity in effect. The oboes often strengthen the violins in unison and the bassoons perform the same service for the basses, but he also used these instruments independently and to embroider the broad and simple themes of the strings. In addition, he made use of the latter and of the wind separately, each body full in itself and responding each to the other. Now and then he used three trumpets, and in his "Rinaldo" he resorts to four, giving the bass to the drums. In "Saul" he uses three trombones. Clarinets were unknown to him, and the bass tuba was unborn in his day; but otherwise he was acquainted with all the instruments of the modern orchestra and made use of them. One cannot recall an instance in which he used them all in combination, and hence, the four trumpets of "Rinaldo" and the three trombones of "Saul" are not heard together in any of his scores. Notwithstanding the fame of Handel, his daring innovations in orchestration do not seem to have been studied by Haydn, or if they were, they exercised no early influence over him. Gluck's scores must be considered epoch-making in the art of orchestration. His "Orpheus" was produced in 1762 when Haydn was thirty years of age; his "Iphigénie en Aulide" was produced in 1774, and the other "Iphigénie" was given in 1779. In these works instrumentation was advanced to an extent that broke almost wholly with the past. When Gluck died Haydn was in his fifty-fifth year, and yet the older composer, the report of whose world-wide fame must have reached Haydn's ears, even in the seclusion of Eisenstadt, does not appear to have suggested anything to Haydn. The twelve great Salomon symphonies, Haydn's, till then, highest achievements in orchestral writing, were not produced until some seven years after Gluck's death, and in them the influence is unmistakably that of Mozart, who had undoubtedly studied Gluck thoroughly.