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which we are now concerned. Here, too, as in Cornwall, vil- 
lages have been covered up by the sand. From the amount of 
calcareous matter which it contains, the sand often produces 
a fertile soil. At Cape Breton the dunes have been planted 
with vineyards for the last two hundred years. 
On the eastern and northern shores of the Baltic there are 
large areas of sand ; and so, too, there are along the shores of 
the North Sea, in a nearly continuous line, as far as the Strait 
of Dover. The dunes on these coasts rarely rise to a great 
height above the sea; 100 feet is quite an exceptional ele- 
vation ; the more common height is about 40 or 50 feet. 
What is wanting in elevation is more than atoned for in breadth. 
Denmark, Schleswig, and Holstein contain together about 260 
square miles of dune-sand, which sometimes extends upwards 
of six miles from the coast.* There are patches of sand in the 
Bas Boulonnais ; but further south, to beyond the mouth of 
the Somme, the area of sand is extensive. Here, too, in 
travelling south, we first meet with high dunes. Near 
Neufchatel (about six miles south of Boulogne) the dunes are 
nearly two miles wide, and attain a height of over 400 feet ; 
possibly the sand has here accumulated over pre-existing hills 
•of chalk. 
Equal in interest to any, and second in importance to none, 
are the dunes of Gascony — known as 44 Les Landes.” These 
extend from the mouth of the Gironde to that of the Adour, a 
distance of nearly 150 miles ; in some places they are six miles 
wide, and rise to heights of over 300 feet. Until planted with 
fir-trees ( Finns maritima ), about the beginning of this cen- 
tury, the sand was in constant motion ; steadily advancing on 
the land, covering fields and villages on its way. The mouth 
of the Adour has undergone some changes in consequence of 
the shifting sands. Originally, as now, the river entered the 
sea at Bayonne ; but in the sixteenth century the sands diverted 
its mouth to about twenty miles further north, at Vieux Boucan. 
It is said that the inhabitants of Bayonne made a passage 
through the sand, thus restoring the river to its former course 
and their city to its old importance. 
It is doubtful to what extent, if any, these and similar dunes 
were originally wooded. It has been supposed that during the 
times of the old forest growth they were covered with trees 
which have been mainly destroyed by man. But if this were 
so, we should expect to find some traces of the old forests 
brought to light during the more modern shiftings of the sands. 
* For this statement, as well as for much of the information which follows, 
I am indebted to the valuable work of Mr. G. P. Marsh, “ The Earth as 
modified by Human Action ” (a New Edition of “ Man and Nature ”), 1874. 
