ANIMAL HEAT. 341 



Such is a large part of the chemistry of re- 

 spiration. Professor Schonbein throws out the 

 hint that ozone may perform an important part 

 in the chemistry of respiration. Other philo- 

 sophers have engaged themselves with the 

 question By what agency are these processes 

 carried on? but hitherto only to arrive at con- 

 flicting results, and to indulge in unsatisfactory 

 speculations. 



Let us now put the following inquiry: If a 

 thermometer were placed under the tongue of 

 an Arctic seaman, and the degree marked by 

 the instrument compared with that indicated by 

 another placed in the mouth of a Hindoo, or 

 any other inhabitant of the burning tropics, 

 would there be any difference between the two 

 points ? In the one case, an icy air seventy or 

 eighty degrees below the temperature natural 

 to the body, would surround the individual ; in 

 the other, a scorching heat, many degrees above 

 that temperature, might envelope him. Yet, 

 notwithstanding this extreme degree of con- 

 trast in external circumstances, there would be 

 actually no difference, or but a very trifling 

 one, between the degree of heat indicated in 

 each case ! 



This wonderful truth informs us of two 

 things 1st. That the animal frame has an in^ 

 ternal source of heat, unaffected by external 



