348 



BEAVER. 



The timber which they use in the construction of 

 both their houses and dams, is very generally drift 

 wood, of which large quantities are always to be met 

 with in the rivers of these wild countries. This of 

 course requires no felling ; and when they find it in 

 the water they can contrive to tow along a large 

 piece ; but if it is on the dry bank at some distance, 

 they must cut in lengths, and bear it on their shoul- 

 ders in the manner which has been already stated. 

 When they have to fell their own timber, they usually 

 have recourse to soft wood, as willow, poplar, and 

 birch ; and they rarely cut any piece even of the 

 drift wood, of more than two or three inches in 

 diameter. Small sizes are indeed preferred ; and here 

 again their instinct is true to mechanical principle, 

 because the working is lighter and the work itself is 

 more compact. The dam is formed with a broad base 

 and a slope both ways, till it is considerably narrower 

 at top ; but however much the level of the bottom may 

 vary, that of the top is made the same all the way; 

 and while, by means of their dam, the colony of bea- 

 vers will sometimes obtain a depth of several feet of 

 water, the current over the top of the dam will be so 

 spread in breadth, that a man may cross without very 

 much wetting his feet. 



It is said that the position of the dam is tempered 

 to the velocity of the current ; and this is certainly 

 no more wonderful than the fact of a dam being made. 

 If the current is slow, the dam is said to be carried 

 straight across ; but if it is rapid, the dam is an oblique 

 line, or a curve with its convexity upward to the 

 stream. This again is true to the mechanical prin- 

 ciple, and true to the adaptation of means to purpose, 

 and of effort to effect, which we so constantly find in 

 nature. The dam straight across is the shortest pos- 

 sible, and therefore costs the least labour ; but it is 

 the one upon which an equal volume and velocity of 

 wafer would act the most powerfully : therefore it is 

 u?ed in those cases where the force of the current is 

 least. The oblique or curved darn is more laborious 

 in the construction, because it must be longer for the 

 same breadth of river ; but as the action of the water 

 upon it diminishes in proportion to the obliquity with 

 which the current meets it, it resists better than the 

 straight dam, and its resistance increases with its 

 obliquity : therefore it is used against the more rapid 

 arid powerful currents. 



But notwithstanding this perfect accordance of 

 instinct with those principles, on account of a far less 

 perfect degree of which, human engineers are apt to 

 be somewhat vain of their science, the beaver is not 

 nature's master. There are combinations of circum- 

 stances, in which the beaver and his dam form no 

 part ; and when these occur, the flood comes rolling 

 on in its power, and not only breaks down the dam, 

 but sweeps away the habitation of the beaver, and all 

 the store of his winter wealth. So true is it that 

 when, in the single instance, reason or instinct appears 

 to our understanding of the matter to have done its 

 best, something unknown to us (though not unknown 

 to nature) comes round and hurls to destruction all 

 that reason plans in the one case, or that instinct 

 executes without plan in the other ; and when we 

 imagine that we have established our position upon 

 the surest basis, our philosophy is driven to the 

 humbling observation of the poet, 



" The best laid schemes o' mice an' men, 



Gang aft aglee ; " 



while we can say no more al'Otit the matter than 

 simply that such is the fact. 



The huts of the beavers are constructed of the 

 same materials as these dams. These houses are im- 

 mediately on the bank, if that is moderately high, and 

 the water proportionally deep, which are circumstances 

 which usually go together; but if the bank is low and 

 the water shallow, they chance a situation a little far- 

 ther off. This appears to be in order that the floor of 

 the hut, which is always excavated a little below the 

 surrounding surface, may.be above the height of the 

 ordinary floods. The securing of a uniform tempera- 

 ture, not too low, appears to be the cause of the par- 

 tial excavation of the hut; and the same practice is 

 followed by the people of the north, when they form 

 their winter habitations of earthy matters, and not of 

 snow. The houses of Iceland, the Feroe islands, and 

 the original ones of Shetland, the Hebrides, and even 

 many parts of the Highlands of Scotland, are formed 

 by partial excavation ; and though they do not accord 

 with southern notions of a comfortable dwelling, they 

 are much more uniformly warm in winter and cool iit 

 summer, than houses raised entirely on the surface, or 

 with their floors elevated above it. These houses 

 are generally entered by a long and low porch, 

 which is the case with the houses of the beavers, 

 though the entrances of them are at some distance 

 below the surface of the water. 



When a family or society of beavers begin to con- 

 struct a house (tor houses are not made by solitary 

 ones), they at first dig a foundation proportional to the 

 number which it is to accommodate ; and the walls 

 are formed of the earth arrd stones which are dug orrt 

 of the foundation, mixed with billets of wood, crossing 

 each other, and thus binding or tying the other 

 materials, so as to prevent them from being separated 

 by the weather. The walls are made of considerable 

 thickness, and so compactly put together, and all the 

 interstices so filled with mud, that they are both water 

 and air tight. When the walls have been raised to 

 the proper height, they are closed in by a sort of dome 

 root, so that the structure is externally something in 

 the shape of a hay-cock. The centre of the floor is a 

 little raised, so that the place where the animals repose 

 may be dry, notwithstanding any moisture which may 

 trickle down the walls. Of this, however, there can 

 be but little, owing to the compactness of the fabric. 

 The principal entrance or entrances (tor there are 

 sometimes two, or even more) are below the surface 

 of the water, to which they exteird sloping trom the 

 edifice itself, and generally have the opening about 

 three feet below the surface, which, in average situa- 

 tions, secures the animals an access to the waier, not- 

 withstanding the frost. A water entrance of this 

 description is called "the angle," by the beaver 

 hunters ; but besides these, there is usually, and pro- 

 bably in all cases, a smaller opening toward the 

 land. Without this last there would be danger of 

 suffocation. There does not, however, appear to he. 

 any ctrrrerrt of air, so that, even in very severe wea- 

 ther, the habitation of the beaver must be snug and 

 warm. 



Authors have stated that these houses have some- 

 times more than one story, and that they are divided 

 laterally by partitions ; but there does not appear to 

 be anv truth in the statement. Their houses are, 

 upon the whole, very rude structures, tar inferior to 

 the nests of some birds, which have no working tools, 

 save the mandibles of their little bills. 



The winter stores of provisions, which consist of 

 branches of trees, from which the animals gnaw the 



