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Show 228 SUPPOSED DIMINUTION OF I 'd d y between t 11 e ti.m e of Pliny and the ninth cehn tury, was a1 r t t wh1. c11 1. t I.S k now n to have risen above t e sea to the exten o . the rate of depression could not have been at the latter perwd, d d ~ r it ought to have fallen much ·J! s was preten e ' IO unl!orm, .a th inth and eighteenth century. more rapidly betwe~n . el n roofs relied on by Celsius and his :Many of the le?r~Ic~ha~ they did not distinguish b~t ween followers, s?ow c th: water by deposition of fresh sediment, the shallo~m? 0~ of de th caused by subsidence of the and the dimmutwn Pt 1·t appeared that the accessions B tl · own statemen s, f sea. YI lde ir nd t 11 e 1o ss of depth ' were at the mouths o o·f new a·n c' ear ta.m d eep b ays, into which it is wel·l kn·o wn that nvers, or m . d b currents. As illustratmg, how-sand and mud are carrie. y f the Gulf of Bothnia into land, 1 dual conversiOn o ever, t le gra . e reat attention. Thus, for example, their observatiOns des£erv gh t t Pitea half a mile was gained h · ted out the act, t a a . . t ey pom d at Lulea no less than a mile m twentyin forty-five years,. ant orts on the same coast, had become ~ight ye~~s. A~c~es7ae!'able 'tracts of the gulf were rendered mland cities. 0 . f fift ears-many old thr~e feet shallower ~n t l:~a':u:~ein~o dr/la~d-small islands fishmg-grounds had een . gt Accordino to Linnreus, the d b · · d to the contmen · o ~a een rl~:d on the eastern side of Gothland near Hobur~, mcrease o three toises annually for ninety years . was ·aa bouht twoh aonrO 'eS I. t was asser ted that along the so.u thernd Besi es t ese c o '1 . t' 1 ·ly 1·n west Prussia an l f the Ba tic par Icu ai shore, a so, 0 · h s an d s'u n k sh 1' ps had been discovered far P. omerama,d an1c h or h these occurrence s wei·e partly accounted mland ; an a t oug f . b d yet the tradition seems for b y .t h e s1' ltm' g up o nver- e s, d at a remote f d' t that a bay of the sea penetrate ' worthy o ere I ' h . hat direction. These, period, much farther to thfe so~t . ~~ ~nterest although they and many other facts, are o geo oglCa , 1 . ' afford no confirmation to the theory of d C~ SI~Sfrom the alleged His most plausible arguments w~re herivBe thni'an and other exposure of certa·m m· su1 a r rocks m t e o tirely covered . d 1 d t have been once en bays, wlnch were ec are o d 11 truded themselves with water, but which had gra ua ·f pr~he course of about more and more above the waves, unti' m * Linn. de tell. habit. iucrem. TilE LEVEL OF THE BALTIC. 229 a century and a half, they grew to be eight feet high. Of this phenomenon, the fol1owing explanation was offered by his opponents. The islands in question consisted of sand and drift-stones, and the waves, during great tempests, threw up new matter upon them, or converted shoals into islands. Sometimes, also, icebergs, heavily laden with rock, were stranded on a shoal or driven up on a low island; and when they melted away, they left a mass of debris, many feet in height. Drowallius, and other Swedish naturalists, pointed out that some of these islands wet·e lower than formerly; so that, by reference to this kind of evidence, there was equally good reason for contending that the level of the Baltic was gradually rising. They also added another curious and very conclusive proof of the permanency of the water-level for many centuries. On the Finland coast were some large pines, growing close to the water's edge; these were cut down, and, by counting the concentric rings of annual growth, as seen in a transverse section of the trunk, it was demonstrated that they had stood there for four hundred years. Now, according to the Celsian hypothesis, the sea had sunk fifteen feet during that period, so that the germination and early growth of these pines must have been for many seasons below the level of the water. In like manner it was shewn, that the lower walls of many ancient castles, such as those of Sonderburg and Abo, reached then to the water's edge, and must, therefore, according to the theory of Celsius, have been originally constructed below the level of the sea. Another unanswerable argument in proof of the stability of the level of the Baltic, was drawn from the island of Saltholm, not far from Copenhagen. This isle is so low that, in autumn and winter, it is permanently overflowed; and is only dry in summer, when it serves for pasturing cattle. It appears, from documents of the vear 1~80, that this island was then also in the same state, and ~xactly on a level with the mean height of the sea, instead of being twenty feet under water, as it ought to have been according to the computation of Celsius. Severa] towns, also, on the shores of the Baltic, as Lubeck, Wismar, Rostock, Stralsund, and others, after six and even eight hundred years, are as little elevated above the sea as at the era of their foundation, being now close to the water's edge. The lowest part of Dantzic was no higher than the mean level |