CHEMICAL STERILIZATION AND DISINFECTION. 85 



view has been strengthened by the experiments of 

 Geppert, in which the reaction was caused to take place 

 between the spores of the anthrax bacillus and a solu- 

 tion of mercuric chloride, the result being the apparent 

 destruction of the vitality of the spores by the forma- 

 tion of this third, inert compound. In these experiments 

 it was shown that though this combination had taken 

 place, still it did not of necessity imply the death of 

 the spores, for if by proper means the combination of 

 mercury with their protoplasm was broken up, many 

 of the spores resumed their vitality, with all their pre- 

 vious disease-producing and cultural peculiarities. Gep- 

 pert employed a solution of ammonium sulphide for 

 the purpose of destroying the combination of spore- 

 protoplasm and mercury ; the mercury was precipi- 

 tated from the protoplasm as an insoluble sulphide, 

 and the protoplasm of the spores returned to its original 

 condition. These and other somewhat similar experi- 

 ments have given a new impulse to the study of disin- 

 fectants, and in the light shed by them many of our 

 previously formed ideas concerning the action of disin- 

 fecting agents have been modified. 



The process of disinfection is not a catalytic one 

 i. e., occurring simply as a result of the presence of the 

 disinfecting body, which is not itself decomposed during 

 its process of destruction but is, as said, a definite chem- 

 ical reaction occurring within more or less fixed limits ; 

 that is to say, with a given amount of the disinfect- 

 ant just so much work, expressed in terms of destruc- 

 tion of bacteria can be accomplished. 



Another point in favor of this view is the increased 

 energy of the reaction with elevation of temperature. 

 Just as in many other chemical phenomena the inten- 



