00-KOO-HOO PLAYS THE GAME 125 



to, to increase the depth and expansion of the pond, and thus 

 the dam grows from a small one of a few yards in length to a 

 big one of several hundred feet — sometimes to even four or five 

 hundred feet in length — that may bank up the water four or 

 five feet above the stream just outside the dam, and turn the 

 pond into a great reservoir covering hundreds of acres of land. 



The dam is more often built of branches laid parallel to the 

 current with their butts pointing up stream, and weighted 

 down with mud and stones; thus layer after layer is added until 

 the structure rises to the desired height and strength. Some 

 dams contain hundreds of tons of material. They are usually 

 built upon a solid bottom, not of rock — though big, stationary 

 boulders often are included in the construction for the extra 

 support they furnish. When thus used, boulders often cause 

 the beavers to divert the hne of the dam out of its usual graceful 

 and scientific curve that well withstands the pressure from 

 even a large body of water. 



The beavers excavate canals — sometimes hundreds of feet 

 in length — to enable them to reach more easily and float home 

 the wood they have cut from freshly felled trees lying far 

 beyond the reaches of their pond. The canals measure from 

 two to three feet in width and a foot to a foot and a half in 

 depth, and are not only surprisingly clean-cut and straight 

 but occasionally they are even provided with locks, or rather 

 httle dams, to raise the water from one level to another — 

 generally about a foot at a time — to off'set the disadvantage of 

 the wood lying on higher and more distant ground than is 

 reached by the waters of the residential pond. Sometimes 

 their canals are fed by springs, but more often by the drainage 

 of rainwater. The building of many of their dams and canals 

 displays remarkable skill and a fine sense of engineering, to- 

 gether with a spirit of perseverance that is astomiding. Is it 

 any wonder that the Indians say that the beavers were once 

 human beings, whom, for the punishment of some miscon- 



