CHANGES WROUGHT IN PATHOLOGY 135 



organized living matter through his colloidal condition 

 seemed close at hand even to GRAHAM. 



The continued application ' of colloidal chemistry to 

 biological problems soon shows, however, the limits which 

 are set upon it. We are able to see this in the case of 

 the antibodies also. How much a knowledge of the 

 colloids contributes toward an understanding of their 

 varied reactions and even the solution of the riddle of 

 their specific sensitiveness toward each other seems most 

 apparent. Our new methods are of no use, however, 

 as soon as we try to discover the secret mechanism by 

 means of which the cells produce a suitable antitoxin 

 against any definite toxin. To repeat the words of 

 GRUBER: " Whence comes this astonishing purposeful- 

 ness, this predetermined harmony, this specific adapta- 

 tion of substance to antisubstance, which one would 

 a priori consider entirely impossible?" 



It must seem remarkable that, instead of exhausting 

 one's self in chemical analogies, one has not sought a more 

 intimate connection * with those phenomena which arise 

 from a direct observation of living matter. Beginning 

 with his classical investigations of the physiology of the 

 senses, EWALD HERING has developed a theory of the 

 changes that go on in living matter, which through abun- 

 dant use of the principle of mobile equilibrium has fore- 

 shadowed modern chemical dynamics. We need only to 

 recall how, according to HERING, the sensations of 

 antagonistic colors correspond with antagonistic reactions 

 in the visual substance which mutually suppress each 

 other. When we consider that the substances of the 



* Only LANDSTEINER makes a similar suggestion. 



