300 FACULTIES OF BIRDS. 



ing generally or locally, is that of health, preservation, 

 or reproduction. The agency by which it operates 

 is that which we denominate, or should denominate, 

 INSTINCT, and the actions by which its sole and 

 uniform aim is accomplished are what we mean, or 

 should mean, by INSTINCTIVE ACTIONS; or, to speak 

 somewhat more precisely, instinct is the operation of 

 the living- principle, whenever manifestly directing; its 

 operations to the health, preservation, or reproduction 

 of a living* frame, or any part of such frame. 



4< The law of instinct, then, is the law of the living 

 principle ; instinctive actions are the actions of the 

 living principle; and either is that power which cha- 

 racteristically distinguishes organized from unorga- 

 nized matter, and pervades and regulates the former, 

 as gravitation pervades and regulates the latter, uni- 

 formly operating by definite means, in definite cir- 

 cumstances, to the general welfare of the individual 

 system or of its separate organs ; advancing them 

 to perfection, preserving them in it, or laying a foun- 

 dation for their reproduction, as the nature of the 

 case may require. It applies equally to plants and 

 to animals, and to every part of the plant as well as to 

 every part of the animal, so long as such part con- 

 tinues alive. It is this which maintains from age to 

 age, with so much nicety and precision, the % dis- 

 tinctive characters of different kinds and species; 

 which, as is noticed in a preceding study, carries off 

 the waste or worn-out matter, supplies it with new, 

 and in a thousand instances suggests the mode of 

 cure, or even effects the cure itself, in cases of injury 

 or disease. It is 'the Divinity that stirs within us' 

 of Stahl, the vis medicatrix naturae of Hoffman and 

 Cullen and the physicians of our own day. It is 

 hence the strawberry travels from spot to spot, and 

 the cod or the cuckoo, with a wider range, from 

 shore to shore, or from climate to climate*." 

 * Book of Nature, ii. 134. 



