INFECTIOUS GERMS. 261 



inconceivable how this can occur ; and yet perhaps 

 it is no more inconceivable or mysterious than 

 most diseases, which, after all, are but derange- 

 ments of the chemical reactions or forces of the 

 animal economy. 



We can manage and control chemical changes 

 quite perfectly when they occur in inorganic bod- 

 ies, and, thanks to science, we can manage tolera- 

 bly well those which occur in the human or animal 

 organization when they happen under ordinary 

 conditions, and are not of too violent a nature. 

 There is a class of reagents called " remedies," 

 which, when rightly used, serve to control in some 

 degree destructive chemical action in the body. 

 We have learned that the poisonous germs which 

 we have had under consideration cannot maintain 

 their vitality in the presence of certain chemical 

 agents, among which are carbolic and cresylic 

 acids, sulphurous acid, the chlorides of some of the 

 metals, etc. These destroy the life of spores, as 

 arsenic or prussic acid destroys life in the human 

 body, and therefore they are the proper agents to 

 employ to arrest the spread of infectious diseases. 

 By using proper caution, by observing the laws of 

 hygiene, by keeping the body clean, and the blood 

 in good condition, by plenty of air and exercise, 

 we can in a considerable degree fortify ourselves 

 against the attacks of poisonous germinal affections. 



