navigable by steamers during flood time (June-December) to the point of confluence with the White Nile. From the N. the Baro is joined by two considerable rivers which also rise in the rampart of hills that separates Abyssinia from the Sudan, but its chief tributaries are from the S. In about 33° 20′ E., 8° 30′ N., it is joined by the Pibor. This river issues from the swamp region east of Bor on the Bahr-el-Jebel stretch of the Nile and flows N.E. and N. It is joined from the E. and S. by various streams having their sources on the W. slopes of the Kaffa plateau. Of these the chief are the Gelo—which breaks through a gap in the mountains in a series of magnificent cascades—and the Akobo. The Akobo rises in about 6° 30′ N., 35° 30′ E., and after leaving the mountains flows N.W. through flat swampy tracts. The whole region of the lower Pibor and Baro is one of swamps, caused by the rivers overflowing their banks in the rainy season. At its junction with the Baro the Pibor is over 100 yds. wide, with a depth of 8 ft. and a speed of 2.3 ft. per second.
Below the confluence of the Pibor and Baro the united stream, now known as the Sobat, takes a decided N.W. trend, passing for some distance through a region of swamps. Just beyond the swamps and some 40 m. below the confluence, is the fortified post of Nasser. From this point the ground on either side of the river gradually rises, though on the S. it is liable to inundation during flood time. From Nasser to the junction of the Sobat with the Nile the river has a course of about 180 m. As it approaches the Nile the Sobat flows in a well-defined channel cut in the alluvial plains through which it passes. The banks become steep, the slope rapid and the current strong. Several khors join it from N. and S., some being simply spill channels. These channels or “loops” are a characteristic feature of the river. The Sobat enters the Nile almost at right angles in 9° 22′ N., 31° 31′ E. It is 400ft. wide at its mouth and has adepth of 18 to 20 ft. at low water and of 30 ft. when in flood. The colour of the water when in moderate flood is that of milk, and it is from this circumstance that the Nile gets its name of Bahr-el-Abiad, i.e. White River. In full flood the colour of the Sobat is a pale brick red. The amount of alluvium brought down is considerable. For the part played by the Sobat in the annual rise of the Nile see Nile.
The Sobat was ascended for some distance in 1841 by the Egyptian expedition despatched in the previous year to explore the upper Nile. The post of Nasser (see above) was founded in 1874 by General C. G. Gordon when governor of the equatorial provinces of Egypt, and it was visited in 1876 by Dr W. Junker, the German explorer. The exploration of the river system above Nasser was carried out in the last decade of the 10th century by the Italian explorer V. Bottego, by Colonel (then Captain) Marchand, of the French army, who, on his way from Fashoda to France, navigated the Baro up to the foot of the mountains; and by Captain M. S. Wellby, Majors H. H. Austin and R. G. T. Bright, of the British army, and others. By the agreement of the 15th of May 1902 between Great Britain and Abyssinia the lower courses of the Pibor and Baro rivers to their point of confluence form the frontier between the Anglo-Egyptian Sudan and Abyssinia.
SOBRAON, a decisive battle in the first Sikh War (see Sikh Wars). It was fought on the 16th of February 1846, between the British (15,000) under Sir Hugh Gough and the Sikhs (20,000) under Tej Singh and Lai Singh. The Sikhs had fortified themselves in a bend on the left bank of the Sutlej, with the river in their rear. The battle began with a two hours' artillery duel, in which the Sikh guns were the more powerful, and the British heavy guns expended their ammunition. Then the infantry advanced with the bayonet, and after a fierce struggle took the Sikh entrenchments. The Sikh losses were estimated at from 5000 to 8000. This battle ended the first Sikh War.
SOBRIQUET, a nickname or a fancy name, usually a familiar name given by others as distinct from a “pseudonym” assumed as a disguise. Two early variants are found, sotbriquet and soubriquet; the latter form is still often used, though it is not the correct modern French spelling. The first form suggests a derivation from sot, foolish, and briquet, a French adaptation of Ital. brichetto, diminutive of bricco, ass, knave, possibly connected with briccone, rogue, which is supposed to be a derivative of Ger. brechen, to break; but Skeat considers this spelling to be due to popular etymology, and the real origin is to be sought in the form soubriquet. Littré gives an early 14th century soubsbriquet as meaning a “chuck under the chin,” and this would be derived from soubs, mod. sous (Lat. sub), under, and briquet or bruchel, the brisket, or lower part of the throat.
SOCAGE, a free tenement held in fee simple by services of an economic kind, such as the payment of rent or the performance of some agricultural work, was termed in medieval English law a socage tenement. In a borough a similar holding was called a burgage tenement. Medieval law books derived the term from socus, ploughshare, and took it to denote primarily agricultural work. This is clearly a misconception. The term is derived from O. Eng. soc, which means primarily suit, but can also signify jurisdiction and a franchise district. Historically two principal periods may be distinguished in the evolution of the tenure. At the close of the Anglo-Saxon epoch we find a group of freemen differentiated from the ordinary ceorls because of their greater independence and better personal standing. They are classified as sokemen in opposition to the villani in Domesday Book, and are chiefly to be found in the Danelaw and in East Anglia. There can hardly be a doubt that previously most of the Saxon ceorls in other parts of England enjoyed a similar condition. In consequence of the Norman Conquest and of the formation of the common law the tenure was developed into the lowest form of freehold. Legal protection in the public courts for the tenure and services deemed certain, appear as its characteristic feature in contrast to villainage. Certainty and legal protection were so essential that even villain holdings were treated as villain socage when legal protection was obtainable for it, as was actually the case with the peasants on Ancient demesne who could sue their lords by the little writ of right and the Monstraverunt. The Old English origins of the tenure are still apparent even at this time in the shape of some of its incidents, especially in the absence of feudal wardship and marriage. Minors inheriting socage come under the guardianship not of the lord but of the nearest male relative not entitled to succession. An heiress in socage was free to contract marriage without the interference of the lord. Customs of succession were also peculiar in many cases of socage tenure, and the feudal rule of primogeniture was not generally enforced. Commutation, the enfranchisement of copyholds, and the abolition of military tenures in the reign of Charles II. led to a gradual absorption of socage in the general class of freehold tenures.
F. W. Maitland, Domesday Book and Beyond, 66 ff.; P. Vinogradoff, Villainage in England, 113 ff., 196ff.; English Society in the 11thCentury, 431 ff.
SOCIAL CONTRACT, in political philosophy, a term applied to the theory of the origin of society associated chiefly with the names of Hobbes, Locke and Rousseau, though it can be traced back to the Greek Sophists. According to Hobbes (Leviathan), men lived originally in a state of nature in which there were no recognized criteria of right and wrong, no distinction of meum and tuum. Each person took for himself all that he could; man's life was “solitary, poor, nasty, brutish and short.” The state of nature was therefore a state of war, which was ended by men agreeing to give their liberty into the hands of a sovereign, who thenceforward was absolute. Locke (Treatise on Government) differed from Hobbes in so far as he described the pre-social state as one of freedom, and held that private property must have been recognized, though there was no security. Rousseau (Contrat social) held that in the pre-social state man was unwarlike and even timid. Laws resulted from the combination of men who agreed for mutual protection to surrender individual freedom of action. Government must therefore rest on the consent of the governed, the volonte générale. Though it is quite obvious that the theory of a social contract (or compact,