Building, the County Court House, Sioux Falls College (Baptist; co-educational; founded in 1883), All Saints School (Protestant Episcopal), for girls, and a Lutheran Normal School (1889). The city is the see of a Roman Catholic and of a Protestant Episcopal bishop. The river falls here about 100 ft. in half a mile and provides good water power for manufactures. The total value of the factory products increased from $883,624 in 1900 to $1,897,790 in 1905, or 114.8%. Sioux Falls is a jobbing and wholesaling centre for South Dakota and for the adjacent parts of Iowa and of Minnesota. A quartzite sandstone, commonly known as jasper or “red granite,” is extensively quarried in the vicinity, and cattle raising and farming are important industries of the surrounding country. A settlement was made at Sioux Falls in 1856, but this was abandoned about six years later on account of trouble with the Indians. A permanent settlement was established in 1867, and Sioux Falls was incorporated as a village in 1877 and was chartered as a city in 1883.
SIPHANTO, Siphéno or Siphno (anc. Siphnos), an island of the Greek Archipelago, in the department of the Cyclades, 30 m S.W. of Syra. It has an area of 28 sq. m., and the population of the commune is 3777 (1907). A ridge of limestone hills—whose principal summits, Hagios Elias and Hagios Simeon, are crowned by old Byzantine churches—runs through the island; for about 2 m. along the western slope stretches a series of villages, each white-washed house with its own garden and orchard. One of these, called after the name of an ancient town Apollonia, is the modern capital; Kastro is an " old-world Italian town " with medieval castle and fortifications, and an old town-hall bearing date 1365. Inscriptions found on the spot show that Kastro stands on the site of the ancient city of Siphnos; and Mr Bent identifies the other ancient town of Minoa with the place on the coast where a Hellenic white marble tower is distinguished as the Pharos or lighthouse, and another as the tower of St John. Churches and convents of Byzantine architecture are scattered about the island. One building of this class is especially interesting—the school of the Holy Tomb or school of Siphnos, founded by Greek refugees from Byzantium at the time of the iconoclastic persecutions, and afterwards a great centre of intellectual culture for the Hellenic world. The endowments of the school are now made over to the gymnasium of Syra. In ancient times Siphnos was famous for its gold and silver mines, the site of which is still easily recognized by the excavations and refuse-heaps. As in antiquity so now the potters of the island are known throughout, the Archipelago. Siphnos was said to have been colonized by Ionians from Athens. It refused tribute to Xerxes, and sent one ship to fight on the Greek side at Salamis.
The wealth of the ancient Siphniotes was shown by their treasury at Delphi, where they deposited the tenth of their gold and silver; but, says the legend, they once failed to do this, and Apollo in his anger flooded their mines. That the mines were invaded by the sea is still evident; and by Strabo's time the inhabitants of the island were noted for their poverty. During the Venetian period it was ruled first by the Da Corogna family and after 1456 by the Gazzadini, who were expelled by the Turks in 1617.
SIPHON, or Syphon (Lat. sipho; Gr. <t'i<j>wv, a tube), an instrument, usually in the form of a bent tube, for conveying liquid over the edge of a vessel and delivering it at a lower level. The action depends upon the difference of the pressure on the liquid at the extremities of the tube, the flow being towards the lower level and ceasing when the levels eoincide. The instrument affords a ready method of transferring liquids. The tube is made of glass, indiarubber, copper or lead, according to the liquid which is to be transferred. The simple siphon is used by filling it with the liquid to be decanted, closing the longer limb with the finger and plunging the shorter into the liquid; and it must be filled for each time of using. Innumerable forms have been devised adapted for all purposes, and provided with arrange- ments for filling the tube, or for keeping it full and starting it into action automatically when required. Pipes conveying the water of an aqueduct across a valley and following the contour of the sides are sometimes called siphons, though they do not depend on the principle of the above instrument. In the siphon used as a container for aerated waters a tube passes through the neck of the vessel, one end terminating in a curved spout while the other reaches to the bottom of the interior. On this tube is a spring valve which is opened by pressing a lever. The vessel is filled through the spout, and the water is driven out by the pressure of the gas it contains, when the valve is opened. The " Regency portable fountain, " patented in 1825 by Charles Plinth, was the prototype of the modern siphon, from which it differed in having a stopcock in place of a spring valve. The " siphon champenois " of Deleuze and Dutillet (1829) was a hollow corkscrew, with valve, which was passed through the cork into a bottle of effervescent liquid, and the “vase siphoïde” of Antoine Perpigna (Savaresse pere), patented in 1837, was essentially the modern siphon, its head being fitted with a valve which was closed by a spring.
SIPPARA (Zimbir in Sumerian, Sippar in Assyro-Babylonian), an ancient Babylonian city on the east bank of the Euphrates, north of Babylon. It was divided into two quarters, “Sippar of the Sun-god” (see Shamash) and “Sippar of the goddess Anunit,” the former of which was discovered by Hormuzd Rassam in 1881 at Abu-Habba, 16 m. S.E. of Bagdad. Two other Sippars are mentioned in the inscriptions, one of them being “Sippar of Eden,” which must have been an additional quarter of the city. It is possible that one of them should be identified with Agade or Akkad, the capital of the first Semitic Babylonian Empire. The two Sippars of the Sun-god and Anunit are referred to in the Old Testament as Sepharvaim. A large number of cuneiform tablets and other monuments has been found in the ruins of the temple of the 'Sun-god which was called E-Babara by the Sumerians, Bit-Uri by the Semites. The Chaldaean Noah is said by Berossus to have buried the records, of the antediluvian world here—doubtless because the name of Sippar was supposed to be connected with sipru, “a writing”—and according to Abydenus (Fr. 9) Nebuchadrezzar excavated a great reservoir in the neighbourhood. Here too was the Babylonian camp in the reign of Nabonidos, and Pliny (N.H. vi. 30) states that it was the seat of a university.
SIPUNCULOIDEA, marine animals of uncertain affinities, formerly associated with the Echiuroidea—(q.v.) in the group Gephyrea. Externally, the body of a Sipunculoid presents no projections: its surface is as a rule even, and often glistening, and the colour varies from whitish through yellow to dark brown. The anterior one-quarter or one-third of the body is capable of being retracted into the remainder, as the tip of a glove-finger may be pushed into the rest, and this retractile part is termed the introvert. At the tip of the introvert the mouth opens, and is surrounded in Sipunculus by a funnel-shaped, ciliated lophophore (figs. 1 and 2). In Phascolosoma and Phascolion this funnel-shaped structure has broken up into a more or less definite group of tentacles, which in Dendrostoma are arranged in four groups. In Aspidosiphon and Physcosoma the tentacles are usually arranged in a horse-shoe, which may be double, overhanging the mouth dorsally. On the surface of the funnel-shaped lophophore are numerous ciliated grooves, and each of the tentacles in the tentaculated forms has a similar groove directed towards the mouth. These grooves doubtless serve to direct currents of water, carrying with them small organisms towards the mouth.
The skin consists of a layer of cuticle, easily stripped off, secreted by an ectodermal layer one cell thick. Within this is usually a sheath of connective tissue, which surrounds a layer of circular muscles; the latter may be split up into separate bundles, but more usually form a uniform sheet. Within the circular muscles is a layer of longitudinal muscles, very often broken into bundles, the number of which is often of specific importance. Oblique muscles sometimes lie between the circular and longitudinal sheaths. On the inner surface is a layer of peritoneal epithelium, which is frequently ciliated, and at the bases of the retractor muscles is heaped up and modified into the reproductive organs. The ectoderm is in some genera modified to form certain excretory glands, which usually take the form of papillae with an apical opening. These papillae give the surface a roughened aspect; the use of their secretion is unknown. They are best developed in Physcosoma.
When the body of a Sipunculoid is opened, it is seen that the body-cavity is spacious and full of a corpusculated fluid, in which the various organs of the body float. The most conspicuous of these is