The greatest genius in opera in this century after Monteverde was Alessandro Scarlatti, of Naples, the principal of the conservatory there, and, we might say, the inventor of the Italian art of singing--_bel canto_. For as there had been no monody, so there had been no solo singing, and as the operas of the first three-quarters of this century, in spite of the improvements of Monteverde, consisted mostly of recitative, there was still no singing in the modern acceptation of the term. Scarlatti introduced new forms. To the _recitativo secco_, or unaccompanied recitative, which until now had been the principal dependence for the movement of the drama, he added the _recitativo stromentato_, or accompanied recitative, in which the instruments afforded a dramatic coloring for the text of the singer. To these, again, he added a third element, the aria. The first he employed for the ordinary business of the stage; the second for the expression of deep pathos; the third for strongly individualized soliloquy. These three types of vocal delivery remain valid, and are still used by composers in the same way as by Scarlatti. His first opera was produced in Rome at the palace of Christina, ex-queen of Sweden, in 1680. This was followed by 108 others, the most of which were produced in Naples. The most celebrated of these were "_Pompei_" (Naples, 1684), "_La Theodora_" (Rome, 1693), "_Il Triompho de la Liberta_" (Venice, 1707) and, most celebrated of all, "_La Principessa Fidele_." In addition to this he wrote a large number of cantatas, more or less dramatic in character. Scarlatti not only created the aria, calling for sustained and impassioned singing, but also invented or discovered methods of training singers to perform these numbers successfully. He was the founder of the Italian school of singing, and the external model upon which it was based undoubtedly was furnished by the violin which, having been perfected by the Amati, as already noted in the previous chapter, and its solo capacities having been brought out by Archangelo Corelli, whose first violin sonatas were published a few years before Scarlatti's first opera, had now established a standard of melodic phrasing and impassioned delivery superior to anything which had previously been known. It was a pupil of Scarlatti, Nicolo Porpora (1686-1766), who carried forward the work begun by his master. Porpora was even a greater teacher of singing than Scarlatti himself, and his pupils became the leading singers in Europe during the first quarter of the eighteenth century. The progress of vocal cultivation was remarkably helped by the fact that at this time women were not permitted to appear upon the stage, all the female parts being taken by male sopranos, _castrati_. These artificial sopranos, having no other career before them than that of operatic singing, devoted themselves vigorously to the technique of their art, and were efficient agents in awakening a taste for florid