252 BALTIMORE of the atmosphere upon different portions of the surface of the sea ; the greatest height of the water corresponding to the greatest de- pression of the barometrical column, and the greatest variation of the barometer in that re- gion, 2^ inches, corresponding to a rise and fall of 34 inches in the water. The waters of the Baltic are much less salt than those of the North sea or the Atlantic ocean ; the rela- tive proportion may be stated as about ^j- to jig- in the North sea. The entire sea is every year more or less encumbered with ice, and its straits are usually impassable from December to April. Severe frosts have made the sea several times passable on the ice in its widest parts, be- tween Denmark and Prussia, especially in the 14th and 15th centuries. In 1809 a Russian army crossed the gulf of Bothnia on the ice. There seems to be no doubt that the Baltic is de- creasing. The innumerable lakes which lie be- tween it and the White sea are but the remnants of what was once a continuous sea. This is proven by the existence of similar animals in those lakes, although these are no longer salt. A gradual drainage is no doubt lessening the vol- ume of all the bodies of water still left in the basin of the Baltic. It is in the south that such changes have been most remarked in modern times. Lubeck, which when originally built was a seaport town, is now 12 m. from the shore. The isle of Rugen is nearly joined to the German shore, and annually extends its bounds, while the names of its various parts show that not long since that which is now one large island was a cluster of small islets. Olof Dalin, a Swedish mathematician, calculated the rise of the shore at one inch per annum, and this is probably not too high. The Baltic is extremely rich in fish of various kinds. Seals are found in considerable numbers, and are chas- ed for their oil and skins. Whales are sometimes seen. Along the shores of East Prussia and the isle of Rugen quantities of amber are col- lected. The countries surrounding the Baltic are all rich in useful natural products, and its waters are therefore crowded with the ships of all nations. The ancients were hut slightly acquainted with the Baltic. The origin of the name Baltic is not certainly known, some ety- mologists deriving it from the Danish belt, a girdle ; some from the Lithuanian balta, white, in allusion to the great quantity of snow which annually falls in its neighborhood. Others have referred it to the Balti, the family name of the kings of the Visigoths. The name, however, is old, and appears to have been first used by Adam of Bremen, who described the sea in the llth century. The most important ports on the Baltic and its various arms are St. Petersburg, Riga, Memel, Konigsberg, Dantzic, Stralsund, Lubeck, Copenhagen, Carlscrona, and Stockholm. BALTIMORE, a northern county of Maryland, bounded N. by Pennsylvania and S. by the Patapsco ; area, 718 sq. m. ; pop. in 1871, 330,741, of whom 47,921 were colored. The larger portion of the surface is undulating, with wooded ridges enclosing fertile valleys, and with hold hills often rising to a height of 800 ft. above tide water. The principal varie- ties of rock are granite, gneiss, hornblende, limestone, and a ledge of primitive rock run- ning through the southeastern portion of the county. On the Great and Little Gunpowder, the Patapsco, Gwynn's and Jones's fulls are large cotton, woollen, and carpet factories, furnaces, founderies, paper and flour mills. Copper and iron are found in considerable quantities, and in this and Harford counties are the most productive mines of chrome in the United States. In the neighborhood of Texas and Cockeysville are extensive quarries of marble, from which came the large mono- liths of the capital at Washington, and the fine-grained alum marble used in building the patent office. The soil is moderately rich. The chief productions in 1870 were 264,568 bushels of wheat, 31,182 of rye, 856,754 of Indian corn, 375,063 of oats, 201,754 of pota- toes, 35,791 tons of hay, and 544,888 Ibs. of butter. The value of the principal manufac- tures in 1866 was : flour and meal, $2,425,887 ; cotton, $2,113,414; machinery, $1,100,000; woollens, $435,250; iron, $612,594; paper, $297,400; hides and leather, $294,981 ; liquors, $162,277. The county seat was transferred in 1854 from Baltimore to Towsontown. BALTIMORE, a city of Baltimore county, Md., ranking sixth in the United States for size and population, situated in lat. 39 17' N., Ion. 76 37' W., on an arm of the Patapsco river, 14 m. from Chesapeake hay, 178 m. from the Atlan- tic, 38 m. by rail N. E. of Washington, 97 m. S.W. of Philadelphia, and 185 m. S.W. of New York. The population in 1790 was 13,503; 1800, 26,514; 1810, 35,538; 1820, 62,738; 1830, 80,625; 1840, 102,313; 1850, 169,054; 1860, 212,418; 1870, 267,354. In 1870, 227,794 were whites and 39,558 colored; 210,870 were natives of the United States, and 56,484 of foreign countries. The arm of the Patapsco on which the city is situated is about 3 m. long, varying in width from | to If m., having its extreme breadth opposite the eastern part of the city, a suburb called Canton. This in- let gives an easy access to the city, and a har- bor sufficiently capacious to contain 2,000 ves- sels. The harbor is divided into an outer and inner bay ; the inner bay is styled the basin, and has but 12 feet of water. The outer bay consists of a harbor between Fell's Point and Canton on the north and east, and Whetstone Point opposite, on the south, and is capable of floating the largest merchant ships. Owing to the accumulation of deposit for many years, the harbor had at one time become shoal in numerous parts, but by proper dredging it has been made available for steamers of the largest class. The entrance to the port is defended by Fort McIIenry, situated on a point of land between the harbor and the Patapsco. This was successfully defended against the British
