126 ADDITIONAL NOTES. 



nance of the nervous power, or the irritability of 

 the muscles,) and that it may thus be only indi- 

 rectly concerned in the calorific function ? 



But setting these speculations aside, it may be 

 observed that respiration is only one of many 

 chemical processes which take place in the 

 animal body, some of which may be supposed to 

 cause an evolution of heat, and others to have a 

 directly opposite eifect ; and if we refer to these, 

 as connected with the higher temperature of 

 warm-blooded animals, we should consider, not 

 what may be the actual quantity produced by 

 any one of them, but what is the amount pro- 

 duced on the whole, after making allowance for 

 that which is wasted by perspiration, and in 

 other ways. 



If we cannot, on purely chemical principles, 

 explain why the integrity of the nervous system 

 is necessary to the maintenance of animal heat, 

 neither can we explain the result of those very 

 remarkable experiments lately made by M. Ber- 

 nard, in which he found that a slight mechanical 

 injury of a certain part of the medulla ollongata, 

 causes a secretion of sugar by the kidneys ; nor 

 why one state of mind augments the secretion of 

 the lachrymal gland, while another deranges the 

 secretions of the stomach and liver. 



But may not the fact admit of another ex- 

 planation ? However unsuccessful the attempts 

 actually to identify the nervous power with elec- 

 tricity may have proved to be, there can be no 



