274 Medicine, 



tion, and the various degrees of exhaustion of sen- 

 sorial power, or torpor from accumulation of sen- 

 sorial power, will be found to ensue. 



After premising these general principles, and de- 

 ducing from them many important doctrines con- 

 cerning; the sound and diseased states of the ani- 

 mal system, Dr. Darwin proceeds to offer his 

 theory of fever, which, whatever may have been 

 the remote cause of it, he supposes to consist in the 

 increase or di:miniition of direct or reverse associated 

 viotions. It commences in a particular organ, oc- 

 cupies one or more disordered tribes or trains of as- 

 sociate motions, and is more or less complicated 

 according to the number of such disordered tribes. 



Dr. Darwin's doctrine of fever may therefore 

 be considered as follows. When the torpor of any 

 part of the system, owing to deficient irritation, oc- 

 casioned either by the subdue tion of the natural 

 stimuli, and consequent accumulation of sensorial 

 power, or by the application of powerful stimuli 

 and consequent exhaustion of the same living prin- 

 ciple, is such as to occasion diminished action of 

 that part, the following effects will take place: 

 the next link of the tribe of associate motions falls 

 also into a torpor, from defect of excitement of 

 the sensorial powder of association, and so the sub- 

 sequent one, till a general torpor affects the sys- 

 tem. This constitutes the cold paroxysm of fever. 

 This general torpor remains till the accumulation 

 of the sensorial power of association is formed, 

 which overbalances that defect of excitement of as- 

 sociation, and then the torpor ceases, and the hot 

 fit of fever is produced. When the torpor of the 

 part first affected is occasioned by the subduction 

 of the natural stimuli, this is likewise thrown inta 

 increased action during the hot fit. But if it arise 

 from exhaustion of sensorial power, the part re- 

 mains in a torpid state during the hot fit. The torpor 



