S72 POISONS, CONTAGIONS, MIASMS. 



energy depends in this case on a chemical action. Light, heat, 

 electricity, or other influences, may increase, diminish, or arrest 

 this action, but they are not its efficient cause. 



In this way the vital principle governs the chemical powers in 

 the living body, and this is particularly apparent with regard to 

 vegetable life. All those substances to which we apply the 

 general name of food, and all the bodies formed from them in the 

 organism, are chemical compounds. The vital principle has, 

 therefore, no other resistance to overcome, in order to convert 

 these substances into component parts of the organism, than the 

 chemical powers by which their constituents are held together. 

 If the food possessed life, not merely the chemical forces, but this 

 vitality, would offer resistance to the vital force of the organism 

 it nourished. 



The equilibrium in the chemical attractions of the constituents 

 of the food is disturbed by the vital principle of the plant, as we 

 know it may be by many other causes. But the union of its ele- 

 ments, so as to produce new combinations and forms, indicates 

 the presence of a peculiar mode of attraction, and the existence 

 of a power distinct from all other powers of nature, namely, the 

 vital principle. 



The vital principle opposes to the continual action of the 

 atmospheric moisture and temperature upon the organism, a re- 

 sistance which is, up to a certain point, invincible. It is by the 

 constant neutralization and renewal of these external influences 

 that life and motion are maintained. 



The greatest wonder in the living organism is the fact that an 

 unfathomable Wisdom has made the cause of a continual decom- 

 position or destruction, namely, the support of the process of re- 

 spiration, to be the means of renewing the organism, and ot 

 resisting all the other atmospheric influences, such as those of 

 moisture and changes of temperature. 



When a chemical compound of simple constitution is introduced 

 into the stomach, or any other part of the organism, it must ex- 

 ercise a chemical action upon all substances with which it comes 

 in contact ; for we know the peculiar character of such a body 

 to be an aptitude and power to enter into combinations and effect 

 decompositions. 



