122 THE AMERICAN BEAVER. 



First section of 84 feet 3 feet high. 



Second 



Thii-a 



Fourth 



Fifth 



Sixth 



100 " 2 



100 " 1 foot 6 inches. 



100 " 1 foot. 



100 " 9 inches. 



67 " 6 " 



Total length, 551 feet. 



For two hundred feet on the east end of the dam, 

 which was its lowest part, it was carried up the stream 

 parallel with its course, and a few rods in front of the 

 rising ground which formed its bank. Here it was 

 constructed almost entirely of mud and sod. This 

 left a narrow channel of water along the crest of the 

 dam, which answered the purposes of a canal, the 

 ground being a swamp on either side. In places it 

 was simply a ditch, excavated in the soft wet earth, 

 the materials being thrown up in the form of a con- 

 tinuous embankment on the lower side, thus forming 

 a low dam with a narrow water channel on the upper 

 side. The excavation was from two to three feet 

 deep, and the embankment rose about six inches high. 

 This seems scarcely credible, especially as it resembled 

 so closely the work of the spade, but nevertheless it 

 was the handiwork of beavers. 



A mile and a half southwest of the mine last 

 named, there is another very fine beaver dam three 

 hundred and eighty feet long, and unusually high 

 and broad throughout its entire extent. It will aver- 

 age three feet high for two hundred feet, and at the 

 centre it is four feet high, and quite massive. The 

 amount of solid materials in this structure is not less 

 than in that at Grass Lake. Mr. John Armstrong, 

 before mentioned, with whom I spent a part of a 

 night upon this dam, captured thirteen beavers upon 



