HYDEOGEAPHY. 



469 



sufficient quantity of mud against it the land will be enclosed ; and this process, 

 it is believed, may be continued until the mouth of the Zuider Zee is reached. 



But far bolder in conception is the proposed drainage of the southern half of 

 the Zuider Zee, which a carefal inquiry has shown to be quite feasible. The main 

 dyke is to stretch across the sea from a point a little to the south of the Yssel 

 mouth, to Enkhuizen, on the coast opposite. It will be 25 miles in length. A 

 ship canal will connect Amsterdam with a port at Enkhuizen, but the principal 

 harbour will be constructed at the back of the island of Urk, which lies in the 

 centre of the dyke. 



The average depth of the portion of the Zuider Zee to be drained is 11*4 feet, 

 and the water contents to be pumped out will therefore be 247,000 million cubic 



Fig. 264. — The Projected Harbour of Urk. 

 Scale 1 : 35,000. 



DEPTH IB FEET 



_______ HalfaMUe. 



feet, irrespectively of 53,000 million cubic feet annually arising from surplus rains. 

 The new polder will be intersected by 2,500 miles of roads and 27,340 miles of 

 canals and drains. Its area will be 486,000 acres, its cost £16,000,000, or £33 an 

 acre ; not a large amount, if we bear in mind that four-fifths of the land to be 

 recovered consist of fertile clayey soil. 



A bolder scheme still than that of draining the Zuider Zee advocates the union 

 of all the islands of Zealand with the mainland, by embanking and draining the 

 estuaries, with the exception of three, which are to form outlets for the Maas, the 

 Rhine, and the Schelde. If realised, Holland would not only gain a large extent 

 of cultivable land, but would at the same time secure better water highways. 



