REACTION OF CELLS 69 



dissociation. The same is true for the hydrogen 

 ion of acids or the hydroxyl ion of bases. They 

 also determined the progress of the disinfection with 

 time. Madsen and Nyman found that this progress 

 corresponds to a monomolecular reaction, and showed 

 that this is also the case when hot water acts on 

 anthrax spores (1907). At about the same time 

 (1908 and 1910) Miss Harriette Chick carried out 

 a very elaborate research on this question and came to 

 similar results when different poisons were used, such 

 as phenol, mercuric chloride, hot water, and normal 

 rabbit's serum. Even when bacteria are killed by 

 drying, the monomolecular law is followed, as Paul 

 found when he kept dried staphylococci at ordinary 

 room temperature. In contrast with this the bacteria 

 remained alive for months at the temperature of 

 boiling liquid air. Miss Chick has also calculated 

 some figures given by Clark and Gage (1903) re- 

 garding the killing of bacteria in sunlight, and even 

 there found the law of monomolecular reactions to 

 hold good. 



In order to prove this I borrow some diagrams 

 from Miss Chick's paper delivered to the Eighth 

 International Congress of Applied Chemistry (vol. 

 xxvi. p. 167, 19 1 2). These diagrams concern the 

 killing of anthrax spores with 5 per cent phenol at 

 333° C. (Miss H. Chick, Fig. 15), or with on per 

 cent mercuric chloride at 18 C. (Kronig and Paul, 

 Fig. 16), the killing of Bacillus typhosus with 06 per 

 cent phenol at 20° C. (Miss H. Chick, Fig. 17), the 

 killing of this bacterium by means of hot water at 



