SEINE-ET-MARNE 328 SEJANUS Seine-et-Oise;; area, 185 square miles. The surface is generally level, with few hills — Mount Valerien, 450 feet (strongly- fortified), and Montmartre, 344 feet, be- ing the highest. The soil is calcareous, but rendered productive by manure sup- plied from the capital. It is traversed by the river Seine. Products, principally vegetables and fruits for the Paris mar- kets; capital, Paris. Pop. about 4,150,000. SEINE-ET-MARNE, a department in the N. E. of France, comprising a part of the old province 'of Ile-de-France, hav- ing N. the departments Oise and Aisne, E. Aube and Marne, S. Yonne and Loiret, and W. Loiret and Seine-et-Oise; area, 2,275 square miles. The surface is un- dulating, and the soil fertile. Rivers, Seine, Marne, Yonne, and Ourcq. Pro- ducts, wheat, oats, rye, barley, potatoes, etc. Numerous cattle and sheep are raised. Manufactures before the World War, cotton and linen fabrics, hardware and cutlery, earthenware, leather and paper. Chief towns, Melun, the capital, Coulommiers, Fontainebleau, Meaux, and Provins. The department suffered se- verely in the German invasion of France in 1914. Meaux was the point nearest to Paris reached by the German armies. Pop. about 363,500. SEINE-ET-OISE, a department of the N. of France, having N. the department of Oise, E. Seine-et-Marne, S. Loiret, and W. Eure and Eure-et-Loire; area, 2,184 square miles. The surface is undulating, and the soil generally fertile. Rivers, Seine, Marne, and Oise. Products, wheat, oats, fruit, vegetables, and cattle. Manu- factures, woolens and printed fabrics, Sevres porcelain, leather, chemicals, and hardware. Chief towns, Versailles, the capital, Mantes, Pontoise, Rambouillet, Etampes, and Corbeil. Pop. about 818,000. SEINE-INFERIEURE, a maritime department of the N. of France, former- ly comprising most of the province of Normandy, having N. and W. the British Channel, E. the departments of Somme and Oise, S. Eure and Calvados; area, 2,448 square miles. The surface is hilly and well wooded. The soil is generally fertile. Rivers, the Seine and its afflu- ents. Products, wheats, oats, barley, rye, flax, hemp, hops, and fruits. Manufac- tures, woolens and cottons, shipbuilding. Chief towns, Rouen, the capital, Dieppe, Havre, Yvetot. Fop. about 877,000. SEIR FISH, or SEER FISH, the Cybi- um gutatum, one of the Scombridse from East Indian seas. In form and size it resembles a salmon, and its flesh, though white, is firm, and very similar to salmon in flavor. SEISIN, or SEIZIN, a right to lands and tenements. In common law seisin signifies possession, as to seize is to take possession of a thing. Seisin is properly applied to estates of freehold only, so that a man is said to be seized of an estate of inheritance, but to be possessed of a chattel interest. There is a seisin in deed, or in fact, when an actual pos- session is taken, and a seisin in law where the lands have descended to a per- son but he has not yet actually taken possession of them. Seisin in deed is obtained by actually entering into the lands. In some of the States, as Penn- sylvania, Massachusetts, Ohio, and Con- necticut, seisin means merely ownership; and the distinction between seisin in deed or in law is not known in practice. SEISMOLOGY, the study of earth- quakes. Though seismology can scarcely be said to have existed before the early part of the 19th century, it has a rapidly growing bibliography, and is accumulat- ing a store of facts and observations on which generalizations may be based. See Earthquake. SEISMOGRAPH, a seismometer; an instrument for recording the period, ex- tent, and direction of each of the vibra- tions which constitute an earthquake. For a complete seismography, three dis- tinct sets of apparatus are required: (1) To record horizontal motion; (2) to re- cord vertical motion; and (3) to record time. The horizontal and vertical mo- tions must be written on the same re- ceiver, and if possible side by side, while at the instant at which the time is re- corded a mark must be made on the diagram which is being drawn by the seismograph. The first instruments were merely modifications of the seismoscope, but successive improvements have been introduced, and the seismograph has been brought to a high pitch of perfection. Some of the best, if not the best forms known are in use in the Imperial Ob- servatory at Tokio, Japan. SEISTAN, or HAMOON, LAKE, a large, irregularly shaped, shallow lake or swamp in the W. of Afghanistan, close to the frontier of the Persian province of Khorassan, a division of which prov- ince (mainly steppe) is named Seistan after it. The lake is not a single expanse of water, but is divided into three de- pressions. A great part of the area is generally dry; but, as the basin has no outlet, when the Helmund and its other feeders are in flood this lake regularly overflows its boundaries, fertilizing large tracts of country. SEJANUS, .ffiLIUS, the son of a Ro- man knight, and noted as the favorite of
