Caspian Sea

Caspian Sea, The. The largest inland sea of the world, lying partly in Europe and partly in Asia, and extending from lat. 36° 40' to 47° 20' N. - a length of 740 miles - and from long. 46° 50' to 55° 10' E.: having an average breadth at the centre of 210 miles, and at its north extremity, where it throws out an arm to the E., a breadth of 430 miles, and has an area of 180,000 square miles. The area of the Caspian must have been, at a not far distant geological period, of much greater extent than now, and it was probably connected with the Black Sea on the W. and the Sea of Aral on the E. Its present level is 84 ft. beneath that of the Black Sea, and 248 ft. below that of the Sea of Aral. The Caspian has three natural basins, a northern and shallow one, which receives the large rivers Volga and Ural, and partly owing to the great quantity of alluvium brought down by them, and partly owing to the great evaporation that takes place, is in process of gradual transformation into salt marsh, in spite of the great volume of water brought down by those rivers. The middle and deep portion of the sea, and the saltest, extends to the Peninsula of Apsheron, where the ridge of the Caucasus enters the sea, and passes as a submarine ridge to the Balkan Peninsula on the eastern side. On the E. side, a bold coast-line formed by the edge of a plateau lying between the Caspian and the Aral recedes, and a large shallow bay is formed, which is terminated by the Balkan Mountains on the south, and is almost cut off from the main sea. This middle basin varies from a depth of 400 fathoms in the centre to one of 30 fathoms upon the ridge above-mentioned. The middle basin receives the Terek, and some smaller rivers which flow through the plain that lies between the Caucasus and the Caspian. The southern basin extends from Cape Apsheron on the W., and follows the shore-line made by the Elburz Mountains round the S. extremity of the sea as far as Astrabad - a Persian town in the S.E. This part receives the Kur, which drains the southern slopes of the Caucasus, and receives the Aras (the ancient Araxes) in its lower course. This river Aras is the boundary between Russian and Persian territory. In the gap that lies between the point where the Elburz range trends from the sea, and the point where the Balkan Mountains touch the sea, the Attrek flows in, and the ancient course of the Oxus is plainly marked as having once led to the Caspian and not as now to the Aral. Another remarkable depression seems to show a former communication between the Caspian and a now dried-up bay of the Aral. The northern shores of the Caspian fade almost imperceptibly into the slope of the steppes. A system of canals between the feeders of the Volga and those of the Duna and Lake Ladoga unites the Caspian with the Baltic. There is a great range of temperature in the Caspian, and in winter the northern, and sometimes part of the middle basin are frozen over. Though there are no tides in the Caspian, it is subject to violent storms of wind which render navigation dangerous. The admixture of sea and river fish in the Caspian is remarkable. Among the former there are seals and herrings and salmon, and the sturgeon with its congeners - so valuable as an article of commerce both for their flesh, and for the caviare and isinglass they supply - is an estuary fish. Naphtha and petroleum abound on the shores; and the Peninsula of Apsheron, with its town of Baku, is saturated with naphtha. The Russians possess three sides of the sea, and have a fleet upon it, and a line of steam packets; and the towns of Astrakhan, Derbend, Baku, and Krasnovodsk, from the last of which a railway runs to Merv and Samarcand, while from Baku a railway runs to the Black Sea. The southern shore is Persian.