Giovanni Battista Pergolesi (1710-1737) was a pupil of Greco, Durante, and Feo. As an opera composer his only success was "La Serva Padrona," an intermezzo which was performed in nearly every theatre in Europe. Among Pergolesi's productions as a church composer, the "Stabat Mater," for two female voices with a string-quartet accompaniment, enjoyed for a while extraordinary popularity. Nicolo Jomelli's (1714-1774) tender and pathetic style rendered him exceedingly popular, both in Italy and in Germany. He wrote sacred and dramatic music. Mozart said of Jomelli: "He is so brilliant in his own particular way that none of us will be able to put him aside: but he should not have attempted to compose church-music in the old style." Nothwithstanding this judgment by Mozart, it is an undeniable fact that Jomelli was the only composer of his time who treated the ecclesiastical style in an almost perfect manner. Giovanni Paisiello (1741-1815) showed his true greatness most clearly on the stage, and attained a reputation so enduring that his best opera, "Il barbiere di Siviglia," produced at St. Petersburg in 1777, was only after great opposition displaced to make room for Rossini's masterpiece of the same name. Nicolo Porpora (1686-1766) was very celebrated as a teacher of singing, but also enjoyed, for some time, great popularity as an opera composer. One of the most important scientific musicians of the eighteenth century was Padre Martini, who was born at Bologna in 1706. He was first taught music by his father, Antonio Maria. He learned singing and violin playing in his youth, and had lessons in counterpoint from Antonio Riccieri, a castrato of Vincenzo and a composer of merit. In 1725, after having been ordained, he became maestro di capella of the church of San Francesco in Bologna. He thus gradually acquired an extraordinary and comprehensive mass of knowledge, with an amount of literary information far in advance of his musical contemporaries. His library was unusually complete for the time. He possessed, for instance, ten copies of Guido of Arezzo's very rare Micrologos. Scientific men of all countries took pleasure in sending him books. It was chiefly in the development of means and details of expression that music was advancing during this period. The art of singing, too, was receiving much attention. The head of the Neapolitan school, Aless. Scarlatti, in addition to his mastery of counterpoint and fugue, was also a great vocal artist, and all his successors tried to cultivate the art of _bel canto_. This art of purified and unsophisticated singing was the foundation-stone in the career of all dramatic composers, and hence their great ability to write in a wholly singable style. [Illustration: GIOVANNI PAISIELLO. From an engraving in Clément's "Musiciens Célèbres."]