FOREIGN CORRESPONDENCE. 
81 
distance of several kilometres, covering fields and vineyards to the 
depth of two or three feet, suffocating vegetation, and transforming 
tlie 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 
frequei:t 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 fi-om Agde (Herault), were 
completely buried under the sands. The houses happened to be uniu- 
liabited at the time, so that no lives were lost ; fortunately also a 
north wind succeeded to the opposite cue which bad 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. Tliis 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, Vmilt behind the dunes, which 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 
Tournay, 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 iipou 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 Heed), 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 plains maritime depuis Boulogne jusqi(,'au Danemark, 
d-c, par MM. Antoine et Alphonse Belpaire. An vers, chez Max. Kornicker. — 
T. L. P. 
VOL. II. 
G 
