Uniformity of the work. 145 



work of the Beaver to meet different conditions of 

 life, than the Honey-bee is called upon to exhibit. 

 But the uniformity, with which Beavers do their 

 work in any given place, and their uniform change 

 of method under different conditions, seem to point 

 to that variation of the instinctive principle, to 

 v/hich we have already referred, rather than to free 

 intelligence, — a variation no greater than is found 

 even in the growth of plants, to adapt them to dif- 

 ferent conditions of Hfe, but which, because in ani- 

 mals it is connected with volition, is very likely to 

 be regarded as a sufficient proof of comprehension in 

 the actor. 



The Muskrat, which is nearly allied to the Bea- 

 ver, has the same sort of variation in his habits to 

 meet the conditions where he is placed. But the 

 variation is so uniform that the animal is plainly 

 under some guiding power which is to him a law of 

 action. Muskrats, whose ancestors have for gener- 

 ations burrowed in the banks of the stream, will at 

 once begin to build houses, if a dam is raised so 

 that they can no longer burrow. And those houses 

 will be built like all other Muskrat houses, the world 

 over. That is, there will be that generic likeness 

 which shows that the lodge is built under the im- 

 pulse and guidance of some principle entirely dif- 

 ferent from the power of comprehension and con- 

 trivance, seen among men. Since it is impossible 

 that all animals of the same species should find 

 places exactly alike to build in, the impulse and 

 guidance, which for a better name we call Instinct, 

 would be folly itself, if it did not vary sufficiently 

 7 



