86 BEAVERS. 



because th^y cut the wood necessary for their building above the 

 spot where they work, and then the current carries it where it 

 is required. If the water is stagnant, they at once commence 

 their houses; but if it is running, they assemble often two or three 

 hundred in a gang, and first form a shelving dam or dyke, to 

 maintain the water at an equal height: this dam is formed of 

 branches interlaced with each other, the intervals of which are 

 filled with stones and mud, and plastered over with a thick solid 

 coat ; it is commonly ten or twelve feet thick at the base, and is 

 sometimes of very considerable extent. At the expiration of a few 

 years it is usually covered with vegetation and thus converted 

 into a substantial hedge. The dam being finished, they separate 

 into small parties of two or three families and set about con- 

 structing their huts, which are built against the dam in the same 

 manner, but with less solidity ; each hut accommodates two or 

 three families ; it has two stories, the upper one being dry for the 

 residence of 'the animals, and the lower one under water, for the 

 store of bark upon which they feed. Only the latter opens ex- 

 ternally, and the entrance is entirely under water. Their work 

 is carried on in the night only, but with astonishing rapidity. 

 When the season of snow approaches, the Castors assemble in 

 great numbers and set about repairing the huts which they 

 had abandoned in the spring, or construct new ones.] 



52. [Beavers, whose coat is ordinarily of a uniform reddish 

 brown, but sometimes of a beautiful black and at others white, 

 are provided with a great abundance of a grayish, soft down of ex- 

 treme fineness, which is concealed beneath long silky hairs, which 

 resisting the water, or not becoming wet, protects them against 

 cold and humidity ; but this fur, which is so useful to them, often 

 becomes the cause of their destruction ; because it is of great 

 use to man, and to procure it these animals are actively pursued. 



53. Beaver skins are an important article of commerce ; they 

 are used as fur, and in the manufacture of hats; the most beau- 

 tiful are from those animals that are killed in winter in the coldest 

 parts of North America. A single skin furnishes about a pound 

 and a half of down which, in France, is worth from thirty-five 

 to forty dollars the pound. As many as one hundred and fifty- 

 thousand of these skins have been imported into Europe in a 

 single year. 



54. Castoreum, an article of commerce also furnished by these 

 animals, is a solid, fragile substance of a strong nauseous odour 



52. What is the colour of the Beaver? Why arc Heavers hunted f 



53. Wlut is the use of Beaver skins ? Are they cheap? 



54. What is Castoreum? 



