238 THE CONTAGIOUS TYPHUS 



rary functions; it pursues its phases, its 

 periods ; and as the functional derangements 

 differ at these several epochs from the deve- 

 lopment of the morbid phenomena, the course 

 of medicine which is employed to check them 

 cannot always be the same. Starting, there- 

 fore, from practical data, we will attend the 

 disease in its gradual advance that is to say, 

 in its distinct periods and will afterwards 

 explain certain predominant symptoms, which, 

 owing to their importance, must likewise fix 

 the attention of the careful therapeutist. 

 It will be remembered that we have recogr- 



o 



nised four periods in the regular course of 

 typhus : 



1st, a period of incubation ; 



2nd, a period of initiation ; 



3rd, a period of duration ; 



4th, a period of decline. 

 But, in the first place, before beginning the 

 treatment, every farmer or grazier, or cattle- 

 owner, who keeps a certain number of cattle, 

 should divide his herd into several classes, in 

 order to regulate and methodize the cares to 

 be given to the sick. 



Thus, he will form a first class, comprising 



