SYMPHONY, in music, a form of orchestral composition. The name was originally applied to the purely instru mental portions of works primarily vo cal, under it being included overtures to operas and oratorios as well as ritornelli and the introduction to choruses and ar ias. It received its first restrictive mean ing toward the end of the 17th century when, under Lulli and Alessandro Scar latti, the various instrumental pieces in the operas began to grow in importance: it was then reserved for the opening sec tion or overture which consisted of a se ries of contrasted movements without definite rule as to their number or ar rangement. Subsequently a plan, attrib uted to Lulli and known as the "ouver ture a la maniere francaise," prescribed three movements, the first and third slow and the middle one quick and bright. Its place was eventually taken by the "Ital ian overture," in which the three move ments were retained but in inverse or der, the first and last being quick and the second slow.
This form was identical with that of the clavier sonata, to which, however, the overture long remained inferior in respect of the internal structure of its move ments, few composers caring to show themselves at their best in pieces to which talkative audiences paid little heed. As a further result of such inat tention it seemed to be forgotten that the overture should fitly foreshadow the work which it preceded: its material, consequently, became distinct and inde pendent, so that it was only natural that the best examples should in course of time find their way into the concert room where they met with a more courteous reception.
It was not, however, till 1788, the year in which Mozart wrote his great exam ples, that the symphony attained the rank of an important work of art. In these three works, the E flat, G minor, and C major symphonies, an extraordinary advance is visible both in expression and in richness of instrumental effect. Haydn, though born nearly 20 years be fore Mozart, wrote his most important symphonies during the 18 years he sur vived his younger contemporary. But the symphony was brought to its most perfect stage of development by Beetho ven.
The Eroica, C minor, and A major stand as the most perfect examples of the classical symphony, and also mark the close of the classical period. For, as the perfection of the symphony was due to the increased value of the subject matter, it was natural when the emo tional domain of music became still more extended that composers should find themselves somewhat circumscribed by the limitations of the old form. Beetho ven himself is an instance of this, for the 9th Symphony he substitutes for the usu al finale an elaborate choral setting of one of Schiller's odes. Succeeding writ ers have mostly aimed at a compromise between their poetical instincts and their regard for conventional rule. Among such may be mentioned Schubert, Spohr, Berlioz, Raff, and Schumann, the work of the last being the most import ant. Mendelssohn was content with the true classical form, and the same in a general way might be said of Brahms.