MAINTENANCE OF THE BODY TEMPERATURE 375 



standard if heat production is increased without a com- 

 pensating increase in heat loss. It will also rise with a 

 uniform heat production if heat loss is interfered with. 

 The fever of the Cornish miners, to which we have re- 

 ferred, illustrates more particularly the second difficulty. 

 The metabolism was not too high to be offset by thermo- 

 taxis if the external conditions had been reasonable. 

 The combination of high temperature with high humidity 

 led to an accumulation of heat in the tissues. 



It may be said of fever in general that it is not so much 

 the result of high metabolism as of a failure of the 

 mechanisms of heat dissipation. It is true that the 

 heat production of the restless patient with his rapid 

 heart and breathing is higher than it would be if he were 

 well and lying comfortably in bed. But it is by no means 

 so high as it might be if he were well and taking exercise. 

 The best statement that we can make regarding fever is 

 that the trouble is with the nerve centers through which 

 the balance between thermogenesis and thermotaxis is 

 normally maintained. When a fever is holding a steady 

 course the balance is, in fact, preserved as delicately as 

 in health. It is the false standard to which the system is 

 held which is the real characteristic. 



It will be well to point out here something which may 

 have been gathered from statements made earlier in the 

 book. This is the fact that our sensations are altogether 

 unreliable as indicators of the body temperature. They 

 are entirely dependent upon the skin. If the surface of 

 the body is warm we say that we are warm. The glow 

 produced by alcohol furnishes this impression, but what 

 is actually sensed on such occasions is the flux of heat 

 from within the body to the exterior. The subject feels 

 warm because heat is escaping through his skin. Sub- 

 normal temperatures have often been recorded when the 

 influence of alcohol has been coupled with exposure to 

 cold. 



Conversely, when the circulation in the skin is abnor- 

 mally reduced the feeling is likely to be one of chilliness, but 





