94 BACTERIOLOGY 



general the case; but the evidence that is rapidly accruing 

 from studies upon disinfectants and their mode of action 

 points strongly to the accuracy of this belief. This reaction, 

 in which the typical structures of both bodies concerned are 

 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 mer- 

 cury and albuminous bodies there results a third compound, 

 which has neither all the characteristics of mercury nor of 

 albumin, but partakes of some of the peculiarities of both; 

 it is a combination of albumin and mercury, commonly 

 known by the indefinite term "albuminate of mercury." 

 Some such reaction as this apparently occurs when the 

 soluble salts of mercury are brought in contact with 

 bacteria. This view has been strengthened by the experi- 

 ments of Geppert, in which the reaction was caused to take 

 place between the spores of the anthrax bacillus and a 

 solution of mercuric chloride, the result being the apparent 

 destruction of the vitality of the spores by the formation 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 previous disease-producing and 

 cultural peculiarities. Geppert employed a solution of am- 

 monium sulphide for the purpose of destroying the combi- 

 nation of spore-protoplasm and mercury; the mercury was 

 precipitated from the protoplasm as an insoluble sulphide, 

 and the protoplasm of the spores returned to its original 

 condition. These and other somewhat similar experiments 

 have given a new impulse to the study of disinfectants, and 



