418 DRAINING OF THE LAKE OF HAARLEM. 
rated from the sea by a chain of low islands, which the sand 
washed up by the tides has since connected with the mainland 
and converted into a continuous line of coast. The best 
authorities, however, find geological evidence that the surface 
occupied by the lake was originally a marshy tract containing 
within its limits little solid ground, but many ponds and inlets, 
and much floating as well as fixed fen. 
In consequence of the cutting of turf for fuel, and the de- 
struction of the few trees and shrubs which held the loose soil 
together with their roots, the ponds are supposed to have grad- 
ually extended themselves, until the action of the wind upon 
their enlarged surface gave their waves sufficient force to over- 
come the resistance of the feeble barriers which separated 
them, and to unite them all into a single lake. Popular tradi- 
tion, itis true, ascribes the formation of the Lake of Haarlem 
to a single irruption of the sea, at a remote period, and con- 
nects it with one or another of the destructive inundations of 
which the Netherland chronicles describe so many; but on a 
map of the year 1551, a chain of four smaller waters occupies 
nearly the ground afterwards covered by the Lake of Haarlem, 
and they have most probably been united by gradual encroach- 
ments resulting from the improvident practices above referred 
to, though no doubt the consummation may have been hastened 
by floods, and by the neglect to maintain dikes, or the inten- 
tional destruction of them, in the long wars of the sixteenth 
century. 
The Lake of Haarlem was a body of water not far from 
fifteen miles in length, by seven in greatest width, lying be- 
tween the cities of Amsterdam and Leyden, running parallel 
with the coast of Holland at the distance of about five miles 
from the sea, and covering an area of about 45,000 acres. By 
means of the Ij, it communicated with the Zuiderzee, the 
Mediterranean of the Netherlands, and its surface was little 
above the mean elevation of that of the sea. Whenever, there- 
fore, the waters of the Zuiderzee were acted upon by strong 
north-west winds, those of the Lake of Haarlem were raised pro- 
