202 ON ALLUVIAL FORMATIONS. 



course throughout that wide space. Lastly, in the year 

 1362, the isles of Fora and Sylt, then forming but one, 

 were divided, and Nord Strand, then a marsch united to 

 the coast, was separated from it. 



During a long time, the inhabitants who survived 

 these catastrophes, and their successors, were so much 

 discouraged, that they attempted nothing more than to 

 surround with, dikes like the former such spaces of their 

 meadow-land as appeared the least exposed to these ra- 

 vages, leaving the rest to its fate. But the common 

 course of causes continually tending to extend and to 

 raise the grassy parts of the sand-banks, and no extra- 

 ordinary combination of circumstances having interrupt- 

 ed these natural operations, later generations, farther 

 advanced in the arts, undertook to secure to themselves 

 the possession of those new grounds. In 1525/. they 

 turned their attention to the indentations made, during 

 the preceding catastrophes, in the borders of the marsches ; 

 the waves, confined in these narrow spaces, sometimes 

 threatening to cut their way into the interior part. In 

 the front of all the creeks of this kind they planted 

 stakes, which they interlaced with osiers, leaving a cer- 

 tain space between the lines. The waves, thus broken, 

 could no longer do injury to the marsch; and their se- 

 diments being deposited on both sides of this open fence, 

 very solid fore-lands were there formed. In 1550, they 

 raised the dikes considerably higher, employing wheelbar- 

 rows, the use of which was only then introduced. For 

 this purpose they much enlarged and deepened the inte- 

 rior canals, in order to obtain more earth, not merely to 

 add to the height of the dikes, but to extend their base on 

 the outer side. At last they began to cover -these dikes 

 with straw ropes ; but this great preservative of dikes 

 was at first ill managed; and the use of it was so slowly 



