THEIR MODE OF ACTION. 



peculiar compounds, which are generated in animals and vegeta- 

 bles, is chemical affinity ; but the cause by which they are pre - 

 vented from arranging themselves according to the degrees of 

 their natural attractions — the cause, therefore, by which they are 

 made to assume their peculiar order and form in the body, is the 

 vital principle. 



After the removal of the cause which produced their union — 

 that is, after the extinction of life — most organic atoms retain 

 their condition, form, and nature, only by a vis inertia ; for a 

 great law of nature proves that matter does not possess the power 

 of spontaneous action. A body in motion loses its motion only 

 when a resistance is opposed to it : and a body at rest cannot be 

 put in motion, or into any action whatever, without the operation 

 of some exterior cause. 



The same numerous causes which are opposed to the forma- 

 tion of complex organic molecules, under ordinary circumstances, 

 occasion their decomposition and transformations when the only 

 antagonist power, the vital principle, no longer counteracts the 

 influence of those causes. Contact with air and the most feeble 

 chemical action now effect changes in the complex molecules ; 

 even contact with any body, the particles of which are under- 

 going motion or transposition, is often sufficient to destroy their 

 state of rest, and to disturb their statical equilibrium in the 

 attractions of their constituent elements. An immediate con- 

 sequence of this is, that they arrange themselves according to the 

 different degrees of their mutual attractions, and that new com- 

 pounds are formed, in which chemical affinity has the ascendency, 

 and opposes any further change, as long as the conditions undo* 

 which these compounds were formed remain unaltered. 



