2 INTRODUCTION. . 



the application of the science itself. Of this kind is the 

 connexion produced amongst the natural objects by the 

 Theory of the System, or the second principal head of the 

 present work. Natural History by no means considers 

 those connexions among different bodies, in which some of 

 them produce alterations in the others, or contain the causes 

 of certain events. 



The peculiar character of History, consists in being a nar- 

 rative or a relation of facts, arranged according to the suc- 

 cession of time. Natural History has nothing to relate, 

 and takes no notice of the succession of events. 



The impropriety of the words Natural History, has ex- 

 ercised a prejudicial influence upon the developement 

 and the progress of the science itself, and has given rise 

 to many misconceptions. All these misconceptions disap- 

 pear as soon as the notion of Natural History is circum- 

 scribed within proper limits. Supposing the existence of a 

 definition of this kind, the name of Natural History can 

 be retained, particularly since it has not, till now, been 

 superseded by another more appropriate expression. 



. 3. NATURAL-HISTORICAL PROPERTIES. 



The properties of a body, in as far as they are 

 considered and made use of in Natural History, 

 are called Natural-Historical Properties. 



The Natural-Historical properties are those with which 

 , Nature has endowed the bodies which it produces, pro- 

 vided these properties, as well as the bodies themselves, 

 remain unaltered during their examination. A body is 

 said to be in its natural state, while it continues to shew 

 these properties. The natural state of a body is either 

 constant, or it is variable during a certain period of time. 

 In the first case, Natural History at once selects such of 

 the invariable properties, as may serve its purpose agree- 

 ably to the principles of the science. In the second, it de- 

 termines before hand the state of the highest perfection, 

 or of the full developement of these bodies, and then makes 



