526 PHYSIOLOGY. 



ing every period of a physician's life. The constant level of tem- 

 perature in man is accounted for by two theories: One that it is 

 due to changes in heat-production; the other, held by a minority, 

 that it is kept so by changes in heat-dissipation under the varying 

 conditions of external temperature. 



In a case of fever generated by the malarial parasite I found 

 with the human calorimeter an increased production of heat as the 

 primary cause of the fever. In the case of fever generated by the 

 subcutaneous injection of putrid blood I found a fever caused by an 

 increased production of heat in the animal. 



As a rule, it is true that fever is set up by an increase of heat- 

 production beyond that of heat-dissipation. But when this is once 

 established the fever continues, not from an excessive production, 

 but from an altered relation between heat-production and heat- 

 dissipation. 



That the basal thermogenic centers, the corpus striatum and 

 tuber cinereum, play a prominent part in the production of fever is 

 proved by the fact that putrid blood and betatetrahydronaphthylamin 

 both produce a rise of temperature. They are powerless after a sec- 

 tion behind the tuber cinereum to elevate the temperature. 



Antipyrin reduces the temperature by an action upon the cor- 

 pora striata. 



Experiments in my laboratory by Dr. W. S. Carter proved .that 

 whilst the temperature of the body has a rhythm, there was no 

 rhythm in either heat-production or heat-dissipation. 



All recent researches go to show that fever is not a fire that is 

 continuously kept up by an excessive oxidation of the constituents 

 of the human body. For instance, if the amount of water flowing 

 into a vessel partly filled with water is equal to 2, and the amount 

 going out is equal to 2, the level of the water will be the same. But 

 if the amount of water going into the vessel is equal to 3 and the 

 amount going out equal to 2, the level of the water will rise. If, 

 however, the amount going into the vessel should suddenly fall to 1 

 and the amount going out should do the same, the level of the water 

 would be nearly the same as before. If, now, you substitute for the 

 amount of water going in the amount of heat produced, and for the 

 water going out the amount of heat dissipated, and the level of the 

 water as the height of temperature, it is easy to see how a dimin- 

 ished production and dissipation of heat due to want of food and the 

 waste of the body by the fever process, may still keep up a high 



