1 62 LECTURES ON IMMUNITY 



tion phenomenon like that of ammonia, is evident from 

 Pauli's investigations. On the addition of acid the wander- 

 ing of the albumen to the cathode at first increases with 

 the quantity of acid added, and then reaches a maximal 

 value. The stronger hydrochloric acid has a greater action 

 than the weaker acetic acid. Evidently the albuminous 

 substance has the character of a weak base and therefore 

 the formation of salt is greater if we use hydrochloric 

 than if we use acetic acid, and a limit of the wandering is 

 reached when the substance is practically neutralised. 



In an analogous manner the sera investigated by Pauli 

 behave with alkalies. The wandering to the anode in- 

 creases with the quantity of alkali added, until a limit is 

 reached. In this case evidently no hydroxyl ions are 

 annexed to the albuminous substance, but instead its "acid" 

 carboxyl group gives off a hydrogen ion and is thereby 

 itself charged negatively as an albuminate ion. 



Pauli found that neutral salts do not give a charge to 

 the serum, but KH 2 PO 4 , which has an acid reaction, and 

 Na 2 HPO 4 , Na 3 PO 4 , NaHCO 3 , and Na 2 CO 3 , which have 

 an alkaline reaction, exert an influence like a weak acid or 

 as weak bases. This is quite clear as long as we regard 

 the albuminous substances as amphoteric electrolytes ; but 

 if we regard them as colloidal particles, we cannot predict 

 anything with respect to the influence of these substances. 

 It is quite incomprehensible how this latter view has been 

 so often preferred. 



The behaviour of albumose, pepton, and of egg-white as 

 bases has been very thoroughly investigated by Sjoqvist, 1 



1 Sjoqvist : Skandinavisches Archiv f. physioL Chemie, Bd. V., p. 59 

 (1895). 



