tt " < l AKJMA1TE AND INANIMATE BODIES. 



certain fixed and invariable properties, they stand 

 uniformly in the same relation to each other, and 

 act invariably according to the same general laws, so 

 that what is once ascertained of them can be pre- 

 dicted with certainty to hold true for ever after ; 

 and, therefore, in conducting our investigations, we 

 know that the same effects will always follow the 

 same causes with mathematical precision. But 

 when the same elementary material becomes part 

 of a living body, this rule no longer holds : the laws 

 of chymical and physical action are greatly modified, 

 or, for a time, counteracted, and the now organized 

 matter obeys the laws of vegetable or animal life, 

 and is not again subjected to those of chymical 

 action, either till eliminated from the body, or till 

 life is extinct ; and, in point of fact, the putrefaction 

 which instantly follows the extinction of the vital 

 principle is neither more nor less than the ordinary 

 laws of inanimate matter resuming their dominion 

 when no longer opposed by a higher power. 



An example or two will render the difference more 

 apparent. All bodies gravitate towards the earth, 

 according to a well-known and invariable law. But 

 animals are able to resist this law, so far as to pre- 

 serve an attitude at variance with its tendency, or 

 even to rise, like the eagle, many thousand feet in 

 the air in opposition to their natural weight ; but, 

 on the extinction of life, they lose this power, and 

 again become subject to the full influence of gravi- 

 tation. In the same way, many anin,als preserve 

 an -elevated and steady temperature, whether ex- 

 posed to severe cold or to excessive heat ; but when 

 life ceases, rapidly assume that of the objects by 

 which they are surrounded. A human being may, 

 for instance, be exposed to the intensest cold of the 

 Polar Regions without having his own internal tem- 

 perature reduced by a single degree so long as life 

 endures ; but from the moment he ceases to exist, 

 his body begins to part with its heat, and ere long it 



