406 DRAINING OF THE LAKE OF HAAELEM. 



cities of Amsterdam and Leyden, running parallel witli the coast 

 of Holland at tlie 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 

 ISTetherlands, and its surface was little above the mean elevation 

 of that of the sea. Whenever, therefore, the waters of the Zuider- 

 zee were acted upon by strong northwest winds, those of the 

 Lake of Haarlem were raised proportionally and driven south- 

 wards, while winds from the south tended to create a flow in the 

 opposite direction. The shores of the lake were everywhere 

 low, and though between the years 1Y67 and 1848 more than 

 $1,700,000 had been expended in checking its encroachments, it 

 often burst its barriers, and produced destructive inundations. 

 In Kovember, 1836, a south wind brought its waters to the very 

 gates of Amsterdam, and in December of the same year, in a 

 northwest gale, they overflowed twenty thousand acres of land 

 at the southern extremity of the lake, and flooded a part of the 

 city of Leyden. The depth of water in the lake did not in gen- 

 eral exceed fourteen feet, but the bottom was a semi-fluid ooze 

 or slime, which partook of the agitation of the waves, and added 

 considerably to their mechanical force. Serious fears were enter- 

 tained that the lake would form a junction with the inland waters 

 of the Legmeer and Mijdrecht, swallow up a vast extent of valu- 

 able soil, and finally endanger the security of a large proportion 

 of the land which the industry of Holland had gained in the 

 course of centuries from the ocean. 



Eor this reason, and for the sake of the large addition the bot- 

 tom of the lake would make to the cultivable soil of the state, it 

 was resolved to drain it, and the preliminary ste23s for that pur- 

 pose were commenced in the year 1840. The first operation was 

 to surround the entire lake with a ring-canal and dike, in order 

 to cut ofl the communication with the Ij, and to exclude the 

 water of the streams and morasses which discharged themselves 

 into it from the land side. The dike was composed of different 

 materials, according to the means of supply at different points, 

 such as sand from the coast-dunes, earth and turf excavated from 

 the line of the ring-canal, and floating turf,* fascines being every- 



* In England and New England, where the marshes have been already 

 drained or are of comparatively small extent, the existence of large floating 



