560 ENCEOACHMENTS OF THE SEA. 



the weatlier and on other varying circumstances, that no general 

 rate can be assigned to it. 



At Agger, near the western end of the Liimf jord, in Jutland, 

 the coast was washed away, between the years 1815 and 1839, at 

 the rate of more than eighteen feet a year. The advance of the 

 sea appears to have been something less rapid for a centm-y be- 

 fore ; but from 1840 to 185Y, it gained upon the land no less than 

 thirty feet a year. At other points of the shore of Jutland the 

 loss is smaller, but the sea is encroaching generally upon the whole 

 line of the coast.* 



The Liimf jord. 



The irruption of the sea into the fresh-water lagoon of Liim- 

 f jord in Jutland, in 1825 — one of the most remarkable encroach- 

 ments of the ocean in modern times — ^is expressly ascribed to 

 "mismanagement of the dunes" on the narrow neck of land 

 which separated the fjord from the IS^orth Sea. At earlier periods 

 the sea had swept across the isthmus, and even burst through it, 

 but the channel had been filled up again, sometimes by artificial 

 means, sometimes by the operation of natural causes, and on all 

 these occasions effects were produced very similar to those result- 

 ing from the formation of the new channel in 1825, which still 

 remains open.f Within comparatively recent historical ages, the 

 Liimf jord has thus been several times alternately filled with fresh 

 and with salt water, and man has produced, by neglecting the dunes, 

 or at least might have prevented by maintaining them, changes 

 identical with those which are usually ascribed to the action of 

 great geological causes, and sometimes supposed to have required 

 vast periods of time for their accompHshment. 



"This breach," says Forchhammer, "which converted the 

 Liimf jord into a sound, and the northern part of Jutland into an 

 island, occasioned remarkable changes. The first and most strik- 

 ing phenomenon was the sudden destruction of almost all the 



* Andresen, Om Klitformationen, pp. 68-73. 



f Id., pp. 231, 233. Andresen's work, though printed in 1861, was finished 

 in 1859. Lyell {Antiquity of Man, 1863, p. 14) says : " Even in the course of 

 the present century, the salt- waters have made one irruption into the Baltic by 

 the Liimf jord, although they have been now again excluded." 



