The universal geography : earth and its inhabitants

THE BALTIC. 21No mountains of floating ice are seen in the Baltic, as in the polar seasbut here and there detached masses rising from 14 to 16 feet above thesurface present a faint image of the fragments of glaciers met with in the watersto the south of Spitsbergen and Greenland. These masses, like those of thoglacial epoch, are occasionally charged with stones and other detritus, thus on asmall scale continuing the transport of erratic boulders, at one time of suchimportance in the geological history of Scandinavia, Finland, and Germany.Scientific records quote a great number of facts bearing witness to this displacementof rocks borne southwards by tho broken masses of ice. Blocks of granite,weighing many millions of pounds, have been thus transported from the coast otFinland to Ilogland Island.*The law of decreasing temperature observed in the Atlantic prevails also inthe Baltic, at least in summer. But the transition is here much more rapid, theinland sea being but slightly affected by the action of the warm currents whichtemper the waters of the northern seas. The lower strata vary in temperature,as in the Atlantic, and are usually very near freezing point. Thus the plummetreaching the bottom in a depth of 50 to 100 fathoms in a very short space traversesliquid strata varying at least 18°.The Baltic is nowhere as deep as the Skager Eak. Between Copenhagenand Bornholm the line never reaches a depth of 32 fathoms ; east of Bornholm,and in the same latitude, it falls to 66 ; but the average is about 44, withno more than 8 fathoms on the Stolpe and some other submarine banks.Farther north, where the Baltic is widest, the depth increases with itsarea. The greatest depression discovered by the Pomcrania in 1871 lies betweenGotland and "Windau, where a depth of 126 fathoms was reached, previous butincorrect soundings having given 200 fathoms. All the harbours, both in thesouth and north, are shallow, being inaccessible to vessels drawing over 16to 20 feet. Still, as a whole, the Baltic is deeper than the North Sca.t Itsbed has, so to say, not yet been levelled, still presenting numerous inequalities,in this respect resembling tho beds of the countless fresh-water lakes in Swedenand Finland.There are no appreciable tides in the Baltic. South of the Straits navigationtakes no account of them, though naturalists are able to verify their presencein the Mecklenburg and Pomeranian ports, determining their rise to withina fraction of an inch. Thus in the harbour of WIsmar the difference betweenebb and flow is estimated at about 3 5 inches. The variation diminishescontinually eastwards, at last escaping the most careful observations. Suchfaint oscillations are as nothing compared with the changes produced by theatmospheric currents. The strong and continuous west winds cause the waterto fall from 4 to 5 feet X in Kiel Harbour, and on the low shores of the Baltic the* Von Baer ; Forchhammer ; Ant. von Etzel, " Die Ostsee."t Area of the Baltic 13S,230 square miles.Mean depth (Meyer)207 feet.Approximate contents29,544, 506 cubic yards.% Mbbius, ''Das Thierleben am Boden der dcutschen Ost und Nord See."VOL. V. 1)