CLEMENTI, MUZIO (1752-1832), Italian pianist and com poser, was born at Rome where his father was a jeweller. At nine he was appointed organist of a church and at fourteen he had written a mass which was performed in public. About 1766 Peter Beckford, cousin of the author of Vathek, brought Clementi to England, where his success both as composer and pianist was rapid and brilliant. In 1777 he was for some time employed as conductor of the Italian opera, but he soon afterwards left London for Paris. Here also his concerts were crowded by en thusiastic audiences, and the same success accompanied him on a tour about the year 1780 to southern Germany and Austria. At Vienna, which he visited between 1781 and 1782, he was received with high honour by the emperor Joseph II., in whose presence he met Mozart, and fought a kind of musical duel with him.
In May 1782 Clementi returned to London, where for the next twelve years he continued his lucrative occupations of fashionable teacher and performer at the concerts of the aristocracy. He took shares in the pianoforte business of a firm which went bankrupt in 180o. He then established a pianoforte and music business of his own, under the name of Clementi & Co. which was very successful. Other members were added to the firm, including Collard and Davis, and it was ultimately taken over by Collard.
Amongst his pupils on the pianoforte during this period may be mentioned John Field, the composer of the celebrated Nocturnes. In his company, Clementi paid, in 1804, a visit to Paris, Vienna, St. Petersburg [Leningrad], Berlin and other cities. While he was in Berlin, Meyerbeer became one of his pupils. He also revisited his own country, after an absence of more than thirty years. In 1810 Clementi returned to London, but refused to play again in public, devoting the remainder of his life to composition. Several symphonies belong to this period but none was published. Of Clementi's playing in his youth, Moscheles wrote that it was "marked by a most beautiful legato, a supple touch in lively passages, and a most unfailing technique." Mozart may be said to have closed the old and Clementi to have founded the newer school of technique on the piano. Amongst Clementi's composi tions the most remarkable are sixty sonatas for pianoforte, and the great collection of Etudes called Gradus ad Parnassum.