152 On the Caterpillar which 



or we return from the effect to the cause, and this is the 

 sum of our knowledge. The key of nature is not com- 

 mitted to us, by which we might unlock the door of her 

 secrets, and surprise her in her work-shop. We can 

 ascend to truth only by industriously and warily piling 

 fact on fact. 



Smellie coincides with the writers already quoted* 

 in his account of the vindictive and malevolent disposi- 

 tions of Caterpillars. He, however, is a mere copyist, and 

 only details what others have observed. He does no- 

 thing more than repeat the experiments of others. His 

 history of their mutual attacks on each other, their cruel 

 wars, and the destruction of the weaker by the stronger, 

 is only a repetition of what Reaumur and others had 

 long since given to the world. But from these accounts 

 we nevertheless deduce a probability, that the malevo- 

 lence, and force, and weapons, which served to inflict 

 mutual death in their own species, might not be altoge- 

 ther useless in carrying on attacks against other animals, 

 between which and themselves there might not be too 

 great a disproportion. 



Smellie is silent on the genera spoken of by Reaumur. 

 He .speaks generally, and, in a very confused, unintelli- 

 gible manner, tells us of Caterpillars becoming flics and 

 butterflies in the same sentence. We are frequently at 

 a loss to attach any definite meaning to his words. This 

 is not a small fault with either a historian or philoso- 

 pher. This writer copies the anatomical opinion, that 

 the circulation in the Caterpillar is from the tail to the 

 head, and in the Chrysalid from the head to the tail. I am 



