HYDROGEAPIIY. 



463 



have been recovered. History takes but little note of these reclamations, for, 

 unlike irruptions of the sea, which destroy the work of generations in a single 

 day, they do not strike the imagination. But the Dutch dyker pursues his task 

 unmindful of the applause of the world, and no sooner has the ocean won a victory 

 than he goes to work to retrieve the disaster. 



The first dykes are supposed to have been constructed by the Northmen, but 

 none of these earlier works of defence survived the disasters of the fifteenth century. 

 It was only when the Dutch had won their independence that the great national 



Fi"'. 258. — The Windmills at Zaanpam. 



task of conquering the ocean was vigorously taken in hand. The draining 

 of the Lake of Zyp, near Alkmaar, 13,820 acres in extent, was, in 1553, the 

 greatest achievement up to that time. The Dutch engineers became famous, 

 and other countries frequently availed themselves of their services. In recent 

 years the work of reclamation has been progressing at an increasing rate. 

 Between 1815 and 1875 142,849 acres of cultivable land have been added to 

 the area of Holland, being at the rate of 6-4 acres daily. The 940,000 acres of 

 land reclaimed to the north of the Maas represent a value, at the rate of £24 an 

 acre, of £23,560,000. 



