Saracenic patterns. The gates were attached to the building covering Mahmud's tomb at Ghazni until their removal to India, under Lord Ellenborough's orders, on the evacuation of Afghanistan in 1842. They are now contained in the arsenal at Agra.
SOMNUS, the Latin name for the personification of sleep, in Greek Hypnos (Ὕπνος). He is the son of Night and the twin brother of Death, with whom he dwells in the darkness of the underworld. At first the difference between the two is strongly marked. While Death is cruel and merciless, and never lets go his prey once seized, Sleep is gentle and kindly, the bestower of rest and pleasant dreams, the soother of care and sorrow. Even Keus is unable to resist his influence, and on two occasions was put to sleep by him at the instance of Hera. In time, however, the conception of Death was greatly modified, until at last he was depicted as a beautiful boy, with or without wings. In like manner, Sleep came to be used as a euphemism for Death. In art the representations of Sleep are numerous and varied. On the chest of Cypselus, Night was depicted holding in her hands two sleeping children—one white (Sleep), the other black (Death). His most common form is that of a vigorous young man, with wings on his forehead; his attributes a stalk of poppy, and a horn from which he drops slumber upon those whom he puts to rest. In Ovid (Metam. xi. 592) the home of Sleep is placed in a dark grotto in the land of the Cimmerians, where he dwells surrounded by a band of Dreams.
See Homer, Iliad xiv. 231—xvi. 672; Hesiod, Theog. 212, 758; Pausanias, v. 18, 1.
SONATA (From Ital. sonare, to sound), in music, originally merely a piece " played " as opposed to " cantata," a piece sung, though the term is said to have been applied once or twice to a vocal composition. By the time of Corelli two polyphonic types of sonata were established, the sonata da chiesa and the sonata da camera.
The sonata da chiesa, generally for one or more violins and bass, consisted normally of a slow introduction, a loosely fugue'd allegro, a cantabile slow movement 1 and a lively finale in some such " binary " form (see Sonata Forms) as suggests affinity with the dance-tunes of the Suite (q.v.). This scheme, however, is not very clearly defined, until the works of Bach and Handel, when it becomes the sonata par excellence and per- sists as a tradition of Italian violin music even into the early 19th century in the works of Boccherini.
The sonata da camera consisted almost entirely of idealized dance-tunes. By the time of Bach and Handel it had, on the one hand, become entirely separate from the sonata, and was known as the suite, partita, ordre or (when it had a prelude in the form of a French opera-overture) the overture. On the other hand, the features of sonata da chiesa and sonata da camera became freely intermixed. But Bach, who does not use those titles, yet keeps the two types so distinct that they can be recognized by style and form. Thus, in his six solo violin sonatas, Nos. 1, 3 and 5 are sonate de chiesa, and Nos. 2, 4 and 6 are called partitas, but are admissible among the sonatas as being sonate da camera.
The sonatas of Domenico Scarlatti (q.v.) are a special type determined chiefly by those kinds of keyboard technique that are equally opposed, on the one hand, to contrapuntal style, and, on the other hand, to the supporting of melodies on a life- less accompaniment. Longo's complete collection of Scarlatti's sonatas shows that, short of the true developed sonata-style, there is nothing between the old sonata da chiesa and Beet- hovenish experiments in unorthodox "complementary keys" that Scarlatti does not carry off with a delightfully irresponsible " impressionism " that enables him to be modern in effect without any serious modern principle. Great, however, as the variety of his forms is now known to be, and numerous as are
1 A movement is a piece of music forming a complete design, or at least not merely introductory; and within such limits as either to contain no radical change of pace or else to treat changes of pace in a simple and symmetrical alternation of episodes. The first complete movement of a sonata seldom leads without break to the others, except in modern examples; but the later movements are often connected.
the newly published slow movements, the normal Scarlatti sonata is that which the concern-player popularizes ; fireworks in binary form, with a perfunctory opening, a crowd of pregnant ideas in the complementary key, and, after the double bar, a second part reproducing these ideas as soon as possible in the tonic. The sonatas of Paradies are mild and elongated work* of this type with a graceful and melodious little second move, ment added. The manuscript on which Longo bases his editioh of Scarlatti frequently shows a similar juxtaposition of move- ments, though without definite indication of their connexion The style is still traceable in the sonatas of the later classics., whenever a first movement is in a uniform rush of rapid motion, as in Mozart's violin sonata in F (Kochel's Catalogue, No. 377), and in several of Clementi's best works.
The sonata in its main classical significance is a work for one or two instruments consisting of a group of movements, four movements being the full scheme; the last movement in the same key as the first ; each movement normally in one tempo, complete in design, independent from the other movements in themes, but aptly related to them in key and style; and constructed in the Sonata Forms (q.v.).
Though, since the time of Bach (when trios were called sonatas), the term is not applied to works for more than two instruments, the full (and even the normal) characteristics of this most important of all instrumental art-forms are rarely revealed except in trios, quartets, &c, and symphonies.
SONATA FORMS, in music. The sonata forms (see Sonata above) cover the whole ground of instrumental music from C. P. E. Bach to the advent of the instrumental lyric as matured by Schumann and of the symphonic poem originated by Liszt. They also have a profound influence on classical opera and vocal music, and hence, by repulsion, upon Wagner, whose life-work consisted in emancipating the music-drama from them. The conditions which developed them were the conditions which made Gluck's reform of opera possible; for they are at once the means and the expression of that 18th-century change in the language of music which made it a truly dramatic medium. Hence our present task is the discussion of the largest and most central problems pure music has ever dealt with; and, while the external technicalities are numerous and prominent, they are significant only so long as we maintain their connexion with those problems with which the true masters (and only the true masters) of the sonata forms are concerned. Much, then, that is essential to the true sonata forms must come under the headings of instru- mentation, harmony, and other musical categories. But here we must confine ourselves to the purely formal aspect, allowing only such allusion to other aspects as will help us to see behind superficial appearances.
1. The Sonata Style. â€” The sonata forms are representative of the type of music that attracts us primarily by its design and its larger contrasts, and only in the second place by the vitality of its texture. In Bach's art the reverse is the case; we listen chiefly to the texture, and our delight in the larger designs, though essential, is seldom more than subconscious. Art-forms existed already in Bach's time, in which the shape, and not the texture, was the object of attention, but these were lighter forrrfs. Bach himself was the greatest master of them, but he never transcended what was then their legitimate limit as an art which is related to his larger work much as decorative designs are related to architecture. Bach's suites and partitas (see Suite) contain (apart from their great preludes, in which other principles are involved) one form embodied in several different dance rhythms, which is the germ from which the sonata was developed. It is sometimes known as the " binary " form; but as some eminent writers classify its later develop- ment as " ternary," we shall here avoid both terms, and refer to it in its earlier manifestations as the " suite " form, and in its later as the " sonata " form. In the suite it may be repre- sented by the following diagram: â€”