FEVER. 



A STUDY IN MORBID AND NORMAL PHYSIOLOGY. 



CHAPTER I. 



THE ESSENTIAL SYMPTOM OF FEYER. 



In approaching a phvsioloijical or pathological process for the purpose of 

 studying its mechanism and nature, its essential symptom sliould, if possible, be first 

 determined as a guide in the unravelling of the mysteries of the process. Fever 

 has been defined to be "an acute derangement of all the i'unctions" ; this it cer- 

 tainly is. Yet the definition gives to the mind no idea of the phenomena of fever. 

 When these are analyzed, it will be found that the most important of them are 

 capable of being grouped in four sets: acceleration of the heart's beat, and dis- 

 turbance of the circulation; nervous disturbance; elevation of bodily temperature; 

 disturbance of nutrition, including secretion. 



It is evident that these four symptomatic groups may have one of two relations: 

 one condition may be the cause of the other, or they may all be simply the result 

 of a common cause. If it can be found by experimentation that each of these 

 conditions can be singly provoked without the remaining conditions being at the 

 same time evolved, it is at once rendered exceedingly probable tliat the relation 

 between these conditions is not causal, i. e., that no one condition is the cause of 

 the others, and that their interdependence does not extend beyond their being the 

 result of some common cause. On the other hand, if experimentation sliows that 

 one of these symptoms or conditions is capable of producing the other conditions, 

 the natural inference is that this is a primary condition, and is really the cause of 

 the others, which are, therefore, secondary states or symptoms of fever. 



The nervous disturbances of fever may be summed up as paresis or convulsions, 

 stupor, coma, delirium. Clinical experience abundantly demonstrates that these 

 do not necessarily induce high temperature or accelerated circulation. The 

 proof of this is so evident that it is not necessary to do more than to allude to it. 

 Again, it is equally sure that increased activity of circulation is not sufficient to 

 induce the high temperature of fever. It is, indeed, true that increased activity of 

 blood movement has some effect upon the animal heat, but tliis effect is, compara- 

 tively speaking, slight. By means of excessive exercise, or liy the use of certain 



1 March, 18S0. ( 1 ) 



