THE COLLOIDAL STATE. 63 



matter. They may be readily illustrated by a few 

 examples. 

 The equations 



A+m =B 



75 Aftflt A ? 



A=l+m+n+ . . . 



represent, when m and m' indicate differently placed 

 O or H 2 O groups, cases in which, as in la, oxidatio n 



FIG. i. FIG. 2. 



and reduction, or hydration and splitting off of water, 

 follow a heterodrome course; or, as in Ila, cases in which 

 the decomposition products are different from the sub- 

 stances employed in the synthesis. 



The principle of antagonistic reactions remains the 

 same whether they take place under the influence of 

 substances that increase the velocity of the reactions, so- 

 called catalyzers,* or not. In the organism we have 

 acting as such catalytic agents mostly ferments, which 

 are capable of acting only upon certain substances, and 



* No doubt the catalyzers determine also the direction of a reaction, in 

 that the reaction follows a qualitatively different course under the influence 

 of different catalytic substances. If one holds fast to the above-mentioned 

 (OSTWALD'S) definition of catalysis, then we would be dealing in this 

 case with several simultaneously possible reactions, of which different 

 ones are accelerated by different catalyzers, while the rest remain not 

 discoverable. 



