AND ANIMAL LIFE. 



CHAP. IX. 



The Influence of Disease on the Production of Heat. 



CCX. To do justice to this subject would 

 require more time than I can at present devote 

 to it, and more correct and multiplied data than 

 the records of medical science furnish. The va- 

 rious states of the pulse, the appearance and quan- 

 tity of the excretions, the expression of the coun- 

 tenance, the colour of the skin, the operation of 

 the mental powers, and many other conditions 

 of the system, have been anxiously inquired 

 after and carefully studied when symptoms of 

 disease were urgent, while the changes in the 

 temperature of the body, or in the distribution 

 of the blood, have never been objects of minute 

 consideration. 



CCXI. We cannot expect to derive much exact 

 knowledge from the ancients ; their ideas con- 

 cerning the source of heat were crude and falla- 

 cious, and their acquaintance with the most im- 

 portant laws of the animal economy, or of the 

 obvious connections of the different organs, or of 

 the degrees of influence which one part of the 

 body exercises over another, was necessarily 

 bounded or empirical. If we turn to the moderns, 

 we have abundance of valuable facts in almost 



