CHAPTER IV. 



Disinfection — Antiseptics — Inorganic salts as disinfectants — The 

 value of corrosive sublimate — Heat. 



In contradistinction to sterilization, disinfection im- 

 plies the destruction of bacteria by chemical processes. 

 In the destruction of bacteria by means of chemical 

 substances, there occurs most probably a definite chemical 

 reaction ; that is to say, the characteristics of both the 

 bacteria and the agent employed in their destruction are 

 lost in the production of a third body, the result of their 

 combination. It is impossible to say with absolute cer- 

 tainty, as yet, that this is the case, but the evidence that 

 is rapidly accruing from the more recent studies upon 

 disinfectants and their mode of action point strongly to 

 the accuracy of this belief. This reaction, in which the 

 typical structures of both bodies concerned is lost, takes 

 place between the agent employed for disinfection and 

 the protoplasm of the bacteria. For example, in the 

 reaction that is seen to take place between the salts 

 of mercury and albuminous bodies there results a third 

 compound, which has neither the characteristics of mer- 

 cury nor of albumin, but partakes of the peculiarities 

 of both ; it is a combination of albumin and mercury 

 known by the indefinite term "albuminate of mercury." 

 Some such reaction as this occurs when the soluble 

 salts of mercury are brought in contact with bacteria. 

 This view has recently been strengthened by the experi- 

 ments of Geppert, in which the reaction was caused to 



