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GERMANY. 



arm of the river at that time flowed along the western heights, in a channel now 

 known as the Old Oder. Frederick II. caused a canal to be excavated along the 

 eastern margin of the swamp, and at an average distance of 15 miles from the 

 old river, thus enclosing an extensive island, which has, however, only partially 

 been drained. The Warthe, the principal tributary river of the Oder, passes 

 through a similar Bruch, or swamp, 40 miles in length, and on an average 10 in 



Fier. 177. — The Ooerbruch. 



2 Mlles. 



width. This river, too, Frederick II. attempted to " regulate " by draining the 

 swamps into the Elbe below Kiistriu, but his scheme has not proved completely 

 successful, and the riverine land is exposed to frequent floods. The Oder is 

 little utilised as a navigable channel. Its upper course, owing to shallows and 

 irregularities of current, can be navigated only with difficulty, and even between 

 Glogau and Frankfort the season of its availability for fully laden barges is limited 

 to forty-two days in the year. For three months annually all traffic is stopped 



