DUNES NATURALLY WOODED. 579 
selves with forests, and the rapidity with which their surface is 
covered by various species of sand-plants, and finally by trees, 
where man and cattle and burrowing animals are excluded 
from them, renders it highly probable that they would, as a 
general rule, protect themselves, if left to the undisturbed ac- 
tion of natural causes. The sand-hills of the Frische Nehrung, 
on the coast of Prussia, were formerly wooded down to the 
water’s edge, and it was only in the last century that, in conse- 
' quence of the destruction of their forests, they became moving 
sands.* There is every reason to believe that the dunes of the 
Netherlands were clothed with trees until after the Roman in- 
yasion. The old geographers, in describing these countries, 
speak of vast forests extending to the very brink of the sea; but 
drifting coast dunes are first mentioned by the chroniclers of 
the Middle Ages, and so far as we know they have assumed a 
destructive character in consequence of the improvidence of 
man. t+ The history of the dunes of Michigan, so far as I have 
* “In the Middle Ages,” says Willibald Alexis, as quoted by Miiller, Das 
Buch der Pflanzenwelt, i., p. 16, ‘‘the Nehrung was extending itself further, 
and the narrow opening near Lochstadt had filled itself up with sand. A 
great pine forest bound with its roots the dune sand and the heath uninter- 
ruptediy from Danzig to Pillau. King Frederick William I. was once in want 
of money. A certain Herr von Korff promised to procure it for him, without 
loan or taxes, if he could be allowed to remove something quite useless. He 
thinned out the forests of Prussia, which then, indeed, possessed little pecu- 
niary value; but he felled the entire woods of the Frische Nehrung, so far 
as they lay within the Prussian territory. The financial operation was a suc- 
cess. The king had money, but in the material effects which resulted from 
it, the state received irreparable injury. The sea-winds rush over the bared 
hills; the Frische Haff is half-choked with sand; the channel between El- 
bing, the sea, and Kénigsberg is endangered, and the fisheries in the Haff in- 
jured. The operation of Herr von Korff brought the king 200,000 thalers. 
The state would now willingly expend millions to restore the forests again.” 
+ Srarine, Voormaals en Thans, p. 231. Had the dunes of the Nether- 
landish and French coasts, at the period of the Roman invasion, resembled 
the moving sand-hills of the present day, it is inconceivable that they could 
have escaped the notice of so acute a physical geographer as Strabo; and the 
absolute silence of Cesar, Ptolemy, and the encyclopedic Pliny, respecting 
them, would be not less inexplicable, 
