AMPHIBIOUS QUADRUPEDS. 255 



branches, to make it lie close and even, and serve 

 as the principal beam of their fabric.* 



This dike, or causey, is sometimes ten, and 

 sometimes twelve feet thick at the foundation. 

 It descends in a declivity or slope on that side 

 next the water, which gravitates upon the work 

 in proportion to the height, and presses it with a 

 prodigious force towards the earth. The opposite 

 side is erected perpendicular, like our walls ; and 

 that declivity, which, at the bottom, or basis, is 

 about twelve feet broad, diminishes towards the 

 top, where it is no more than two feet broad, or 

 thereabouts. The materials whereof this mole 

 consists, are wood and clay. The beavers cut, 

 with surprising ease, large pieces of wood, some 

 as thick as one's arm or thigh, and about four, 

 five, or six feet in length, or sometimes more, ac- 

 cording as the slope ascends. They drive one 

 end of these stakes into the ground, at a small 

 distance one from the other, intermingling a few 

 with them that are smaller and more pliant. As 

 the water, however, would find a passage through 

 the intervals or spaces between them, and leave 

 the reservoir dry, they have recourse to a clay, 

 which they know where to find, and with which 

 they stop up all the cavities both within and 

 without, so that the water is duly confined. They 

 continue to raise the dike in proportion to the 

 elevation of the water, and the plenty which they 

 have of it. They are conscious likewise that the 

 conveyance of their materials by land would not 



* Spectacle de la Nature. 

 47 



