NATURAL HISTORY. 47 



Avorld are left to themselves, independently of human policy, there is 

 an equilibrium kept up among the animals by themselves. But this 

 natural government does not concern the human ; and, as no use arises 

 from it [to man], it rather becomes matter of curiosity to consider it. 

 But, to make this natural disposition of animals subservient to human 

 society, we are to consider only those animals that destroy other animals 

 that are hurtful to that society and are of no hurt themselves ; or, at 

 least, [if the animals so destroyed are not hurtful, yet] the good that 

 arises from them is more than the evil. 



It is very remarkable that this [relation] has been so little attended to, 

 as very great advantages would arise from it ; and it is still more re- 

 markable that those animals that are of most use in this respect [in 

 destroying other animals] are some of the most inoffensive, and yet are 

 supposed to be the most offensive and are the most dreaded by the 

 people in general. 



Natural historians are more pleased if they can class an animal, than 

 they would be if they could show any use such animal could be to society. 

 Indeed all philosophy would be of much more use than it is at present 

 if it was adapted to common life : but this is letting themselves [the 

 philosophers] too low ; therefore they must seem learned by some jargon 

 or other. I shall here keep as free of that as possible, and adapt this 

 [Essay] to the ignorant, or rather to those that have an opportunity of 

 applying it to practice. 



The animals that I shall talk of are of the Insectivorous and Vermi- 

 vorous kinds ; viz. the snake, the viper, the lizard, the hedgehog, the 

 frog, the toad, the mole, and the bat. These animals live entirely upon 

 worms, snails, beetles, flies, butterflies, both in their grub- and fly- 

 state, spiders, grasshoppers, ants, locusts, mice. Now, few of these 

 creatures are of any use that we know of; but we shall suppose that 

 they are of use : yet, from our first observation we must suppose that 

 they are not of so much use as harm if left to themselves ; or, in other 

 words, as the use arising to the others in destroying them [i. e. of no 

 other use than as prey to their destroyers] : else we must be obliged 

 to suppose the others [destroyers] to be of no use. 



Many worms seem to live upon earth ; but that is of its fattest parts : 

 for, we find them most plentiful in fat ground ; and, indeed, we might 

 reasonably suppose so. As most animals naturally take that which is 

 most substantial, what service they (worms) can be of in living upon 

 earth I cannot say ; but we at once see the hurt that must arise from it. 

 Gardeners suppose them hurtful, which is the reason of their destroying 

 them. Snails would seem to be more hurtful than worms ; for, though 

 they do not eat the fat of the earth which is to produce vegetables, yet 



