176 EXTRACTS FUOM KOTE-BOOKS. CH. XXXI . 



fectly understood by tliem as if they could commu- 

 nicate by words. 



It is difficult to determine how far we are right 

 iu endeavouring utterly to destroy one kind of ani- 

 mal or bird in order to increase another species. 

 Nature, if left to herself, keeps up a fair equilibrium 

 and proportion amongst all her productions ; and, 

 without doubt, if the world were left to itself with- 

 out the interference of mankind, there would never 

 be an luidue jiroportion of any one kind of living 

 creature : the birds of prey would keep down the 

 granivorous birds from increasing till they devoured 

 all the fruits of the earth ; and the carnivorous 

 birds and beasts would never entirely extirpate any 

 other species, as their own numbers would be les- 

 sened by want of food before this could happen ;, 

 besides which, we see that unless artificial means 

 are resorted to, the number of living animals always 

 bears proportion to, and is regulated by the supply 

 of food which oiFers itself ; and, as these supplies 

 fail, there is a natural tendency for the consumers 

 to cease increasing, or to betake themselves to other 

 regions. But when man comes in as an active agent, 

 he gradually extirpates all beasts and birds of prey 

 for the purpose of protecting and causing to increase 

 the weaker but more useful animals and birds. In 

 this country, for instance, we can no more afford to 



