The Builders. 89 



and meeting at a sharp bevel. The inner sides of the 

 teeth are softer and wear away faster than the outer, 

 so that the bevel remains the same ; and the action of 

 the upper and lower teeth over each other keeps them 

 always sharp. They grow so rapidly that a beaver 

 must be constantly wood cutting to keep them worn 

 down to comfortable size. 



Often on wild streams you find a stick floating 

 down to meet you showing a fresh cut. You grab it, 

 of course, and say : " Somebody is camped above here. 

 That stick has just been cut with a sharp knife." But 

 look closer ; see that faint rids^e the whole lenQ-th of 

 the cut, as if the knife had a tiny gap in its edge. 

 That is where the beaver's two upper teeth meet, and 

 the edge is not cpiite perfect. He cut that stick, 

 thicker than a man's thumb, at a single bite. To 

 cut an alder having the diameter of a teacup is the 

 work of a minute for the same tools; and a towering 

 birch tree falls in a remarkably short time when 

 attacked by three or four beavers. Around the stump 

 of such a tree you find a pile of two-inch chips, thick, 

 white, clean cut, and arched to the curve of the bea- 

 ver's teeth. Judge the workman by his chips, and 

 this is a good workman. 



When the dam is built the beaver cuts his winter 

 food-wood. A colony of the creatures will often fell 

 a whole grove of young birch or poplar on the bank 



