BEAVER CANALS, MEADOWS, AND TRAILS. 195 



small stream. In the third place, they often term- 

 inate in dry hard earth at the foot of the rising 

 ground. There is not, in the fourtli place, the slight- 

 est current in these canals showing that they are fed 

 by springs. In the fifth place, surface water, filtering 

 through grounds substantially level, never could cut 

 such uniform, and, much less, such deep ctiannels. 

 And in the sixth and last place, roots of trees, four 

 inches in diameter, are found cut off and removed to 

 afford an unobstructed channel. In like manner, 

 alder bushes, which branch low, as well as send out 

 strong roots, are found cut off in large numbers where 

 they overhang and line their borders. An inspection 

 and comparison of a number of these canals leave no 

 doubt whatever of their artificial character. 



The first canal to be described, and which is shown 

 in Plate XYIII., is on the north side of the pond rep- 

 resented in the preceding plate. For the distance 

 of four hundred and fifty feet it is cut through level 

 ground, and filled with water from the pond. There 

 are knolls or hummocks scattered over the surface in 

 which tamarack and spruce trees are rooted; but 

 there is no perceptible ascent until the first dam is 

 reached, when there is a rise of about a foot. The 

 banks of the canal, which are vertical, rise a few 

 inches above the level of the water with which it is 

 filled. Up to this dam it is perfectly evident that the 

 water in the canal is supplied from the pond. Twenty- 

 five feet above there is a second rise of about a foot, 

 and here we find a second dam, extending over seventy- 

 five feet beyond the canal on one side, and twenty- 

 seven on the other. As here used, these dams are 

 exceedingly ingenious. They were designed to receive 



