368 SAND-PLAINS OF BELGIUM. [March 



it is left dry. Then it is exposed to the sharp sea-breeze, which seems 

 almost never to rest. This seizes on all the finer constituents of the 

 deposit ; and when the gale rises to a storm, it does this with those 

 somewhat larger, and bears both away farther inland. And as the 

 wind is thus subjected to many different weakening influences from 

 the varied form and contour, and composition of the land, as a 

 consequence it drops its lading of sand, etc., in various ways and 

 different places, whereby in course of time there is towered up along 

 the strand a wild and often mountain-like range of sand-hills, to 

 which the designation of sea strand-dunes is given. 



"As every dune acts to some extent as a protecting wall to the 

 land lying beyond, it follows that the sand-dunes shoot out their 

 boundary on the landward side ; and in like manner the fringe of 

 sand-dunes lining the sea is in different places of very different 

 breadths. As in sand-plains the sea is in consequence uninterrupted 

 through artificially - created obstacles, it comes to pass that iu 

 front of these there are ever formed new dunes, whereliy the edging 

 is broadened. And often it happens that a similar broadening of 

 this is occasioned by the travelling of the naked dunes into the 

 interior of the country. When, again, we find the old dunes being 

 thus broken up, we sometimes find the breadth of the belt formed 

 by them diminished. 



" Also, we find, when the material of the broken-up dunes obtains 

 an adjacent resting-place, that the strand-dunes assume the figure 

 of three lesser ranges of sand-hills with intermediate connections. 

 First, the lower dunes, which receive immediately the new material 

 brought by the waves ; secondly, the high dunes behind these, 

 which, when tliey have attained their maximum size, subsequently 

 receive the drift - sand, and thus are raised higher and higher, 

 and so supply shelter from the sand and the wind to the lands 

 beyond ; and tliirdly, the inner dunes, that is, the range of lower 

 sand-hills lying behind the high dunes formed from these sand- 

 masses. 



" As the .sea-breeze is more variably .strong and violent than are 

 tlie winds blowing over consolidated land, the strand-dunes take a 

 much wilder form than do inland dunes, and in consequence of the 

 restriction on the supply of material in these, they attain a greater 

 elevation than do they; and from the same circumstance, the division 

 just mentioned of the strand-dunes into three ranges is scientifically 

 correct, and more distinctly to be traced in nature." 



{To he continued.) 



