54 PRINCIPLES OF VEtERINARV SIfRGfiRY 



more water after its temperature has been reduced to normal 

 by cold baths, than a healthy animal. This experiment alone 

 is ample proof that fever depends largely upon increased 

 generation of heat, in fact that it is due to augmented oxida- 

 tion of the blood and the tissues. The increased elimination 

 of urea and other products, even when nifcrogenized food is 

 withheld, still further confirms the hypothesis. And fur- 

 thermore there is always an increased elimination of carbonic 

 acid — the end product of combustion — in a fever patient. 



Fever being due to both diminished loss and increased 

 production of heat, the real cause must be found in a disturb- 

 ance of the regulating apparatus, — the nervous system. It is 

 well known that the animal body is capable of, and in fact 

 does, generate enough heat in twenty-four hours to coagulate 

 the living protoplasm ; that is to say, the body would be 

 burned up in less than twenty-four hours were it not for the 

 inhibition to which the mechanism is subjected. Exception- 

 ally high temperatures are often supposed to be caused by im- 

 perfect elimination of heat, which statement cannot be en- 

 tirely contradicted, but the fact that fever does not run riot 

 and burn up the body when the eliminating mechanism is 

 completely suspended points to the existence of an internal 

 governor, the disturbance of which is the actual cause of ele- 

 vations of temperature. 



High temperature must not, however, be confused with 

 increased combustion. A very high temperature may be 

 caused by only a nominal degree of increased combustion, 

 when the elimination is impaired, while on the other hand 

 a nominal elevation of the temperature may in reality ema- 

 nate from a markedly increased combustion because of the 

 normal state of elimination. 



Heat-production being the chief factor in fever, the ques- 

 tion of its cause naturally arises. In this connection various 

 theories have been advanced.. The oldest one ascribes fever 



