INSTINCTS. 201 



prise when familiarity has once laid the sentiment asleep. 

 But could we forget all that we know, and which our spar- 

 rows never knew, about oviparous generation — could we 

 divest ourselves of every information but what we derived 

 from reasoning upon the appearances or quality discovered 

 in the. objects presented to us, I am convinced that harle- 

 quin coming out of an egg upon the stage is not more aston- 

 ishing to a child, than the hatching of a chicken both would 

 be, and ought to be, to a philosopher. 



But admit the sparrow by some means to know that 

 within that egg was concealed the principle of a future bird ; 

 from wdiat chemist was she to learn that icarmth was nec- 

 essary to bring it to maturity, or that the degree of warmth 

 imparted by the temperature of her own body w'as the de- 

 gree required ? 



To suppose, therefore, that the female bird acts in tliis 

 process from a sagacity and reason of her ow^i, is to suppose 

 her to arrive at conclusions which there are no premises to 

 justify. If our sparrow, sitting upon her eggs, expect young 

 sparrow^s to come out of them, she forms, I will venture to 

 say, a wdld and extravagant expectation, in opp ition to 

 present appearances and to probability. She must have 

 penetrated into the order of nature further than any facul 

 ties of ours will carry us ; and it has been w^ell observed 

 that this deep sagacity, if it be sagacity, subsists in conjunc 

 tion with grea^ stupidity, even in relation to the same sub- 

 ject. "A ch .mical operation," says Addison, " could not be 

 followed wdilj greater art or diligence than is seen in hatch 

 ing a chickfi' , yet is the process carried on without the 

 least glimm' ring of thought or common-sense. The hen 

 will mistake a piece of chalk for an egg — is insensible o{ 

 the increaiif or diminution of their number — does not dis- 

 tingaish between her own and those of another species — is 

 fri/^htciicd when her supposititious breed of ducklings take 

 ibe watoL'." 



Fnt il will be said, that what reason could not do for the 

 9* 



