S 40 Medicine, [Chap. IV. 



tained in the natural degree. The first may take 

 place either in consequence of excess of sensorial 

 power, the stimuli being in their accustomed de- 

 gree ; or in consequence of excess of stimuli, the 

 sensorial power being in its natural degree ; or in 

 consequence of excess of both. The second may 

 arise either from want of sensorial power, the 

 stimulus being in its usual degree -, or, from sub- 

 duction of stimuli, the sensorial power being in its 

 natural quantity ; or from want of sensorial power 

 and subduction of stimuli. The third takes place, 

 when both the sensorial power and the stimuli are 

 in proper degree. In some cases, the .morbidly in- 

 creased, as well as the morbidly diminished, actions 

 of the mtroductory link of a circle of associate mo- 

 tions are followed by similar actions of the other 

 links ; at other times, by contrary actions : in the 

 former case there is direct, in the latter reverse, 

 sympathy. The morbidly diminished actions aris- 

 ing from subduction of stimuli are sooner relieved 

 than such as are occasioned by want of sensorial 

 power. The morbidly increased actions which 

 arise from excess of sensorial power are more vio- 

 lent than those which are produced by excess of 

 stimuli. Hence inilammatory diseases are com- 

 monly preceded by subduction of stimuli, and con- 

 «3quent accumulation of sensorial power. But 

 when excess of sensorial ])ower is acted upon by 

 excess o^ stimuli, the exertion which follows is 

 far greater and more destructive. Hence the mor- 

 tiiicatiou of frozen limbs Vvhen brought near the 

 fire. 



According to Dr. Darwin, all those parts which 

 arc subjected, during health, to perpetual action, as 



