492 PRACTICE OF PHYSIC. 



the action of the heart and larger arteries, is, for the time, extreme- 

 ly weakened. Together with this, the languor, inactivity, and 

 debility of the animal motions, the imperfect sensations, the 

 feeling of cold, while the body is truly warm, and some other 

 symptoms, all shew that the energy of the brain is, on this oc- 

 casion, greatly weakened ; and I presume that, as the weakness 

 of the action of the heart can hardly be imputed to any other 

 cause, this weakness also is a proof of the diminished energy of 

 the brain. " So I conclude, that a debility of the nervous power 

 forms the beginning of the cold fit, and lays the foundation of 

 all the other phenomena."" 



XXXVI. I shall hereafter endeavour to shew, that the most 

 noted of the remote causes of fever, as contagion, miasmata, cold, 

 and fear, are of a sedative nature, and therefore render it probable 

 that a debility is induced. Likewise, when the paroxysms of a 

 fever have ceased to be repeated, they may again be renewed, 

 and are most commonly renewed by the application of debilitat- 

 ing powers. " This is illustrated in the case of tertians, which 

 cease for a period or two, and then recur, commonly after the 

 application of some debilitating power, as cold, fatigue, &c. 

 Celsus remarked the power of habit in such cases, and founded 

 a prudent precept on it." And farther, the debility which sub- 

 sists in the animal motions and other functions through the 

 whole of the fever, renders it pretty certain that sedative or 

 debilitating powers have been applied to the body. 



XXXVII. It is therefore evident, that there are three states 

 which always take place in fever ; a state of debility, a state of 

 cold, and a state of heat ; and as these three states regularly 

 and constantly succeed each other in the order we have men- 

 tioned them, it is presumed that they are in the series of cause 

 and effect with respect to one another. This we hold as a mat- 

 ter of fact, even although we should not be able to explain in 

 what manner, or by what mechanical means these states several- 

 ly produce each other. 



" Dr. Hoffmann's system goes no further than the spasm and 

 hot fit, not taking in debility at all ; and I own that I have as- 

 sumed the existence of this state of debility previous to the spasm 

 before it has been clearly proved to exist in every case. When 

 we come to consider the cases of inflammation and hacmorrhagy, 



