FOREIGN CORRESPONDENCE. 



81 



distance of several kilometres, covering fields and vineyards to the 

 depth of two or three feet, suffocating vegetation, and transforming 

 the richest cultivation into a desert waste. 



The only effectual means of counteracting this evil is to plant 

 tamarisks along the coast, so as to form a barrier. But instances are 

 frequent where neither plantations nor walls have been sufficient to 

 prevent the sands from covering roads and fields. Last August two 

 houses, several storeys high, about a mile from Agde (Herault), were 

 completely buried under the sands. The houses happened to be unin- 

 habited at the time, so that no lives were lost ; fortunately also a 

 north wind succeeded to the opposite one which had brought the sand, 

 and blew it away again. 



M. Marcel de Serres, in studying this phenomenon, has observed 

 that these shifting sands form two distinct zones : the first, con- 

 sisting of very fine sand, contains very few shells or scarcely any organic 

 matter; the second contains a large proportion of shells, rounded 

 shingle, and fragments of rock. This second zone remains near the 

 coast, whilst the former one is carried inland, as before stated. Not- 

 withstanding their disastrous effects, these sands, when mixed with 

 rich mould, make an excellent soil for growing vines. 



In a former number of The Geologist we intimated that we would 

 return again to the geology of the Belgian shores. The short note of 

 M. Marcel de Serres furnishes us with the occasion of adding a few 

 more remarks on the sand-hills of the coast of Flanders. These too, 

 in spite of the influence of vegetation, have encroached upon the land 

 to a considerable extent, and gradually progress each year a little 

 towards the interior. It is a well-known fact that the town of 

 Ostend originated in a little village, or rather in a few fishermen's 

 huts, built behind the dunes, wjiich protected them from the strong 

 winds, but at the present day Ostend stands out into the sea. It 

 holds its ground, although the town is considerably below high-tide 

 level, by means of a magnificent pier, built of the black limestone of 

 Toimiay, and constantly kept in good repair. In other localities 

 upon the Flemish coast the sea has encroached dangerously ; for 

 instance, in the Dutch village of Scheveningue some of the buildings 

 are washed by the waves.* 



The only means of impeding the sand-hills in their destructive 

 progress consists in promoting the growth of certain plants on the 

 dunes. Three or four plants are particularly beneficial in this respect, 

 as regards the coast of Flanders ; and botanical remarks upon this 

 coast will be likewise applicable to the sandy portions of the English 

 shores. They are certain grasses, especially Eiymus arenarius (Upright 

 Sea Lyme-grass) and Arundo arenaria (Sea Beed), the long creeping 

 roots, or rather rhizomes of which bind the sand together, furnish it 



* With respect to these remarkable changes, consult the valuable work of MM. 

 Belpaire, entitled : — De la plaine maritime depuis Boulogne jusqu'au Banemark, 

 <tc., par MM. Antoine et AlpJionse Belpaire. Anvers, chez Max. Kornicker. — 

 T. L. P. 



VOL. II. 



G 



