24 



MACDOUGAL— ACTION OF BASES AND SALTS 



took place in the potassium solution at PH of 6.6 and in the acid at 

 PH of 3 and 2. It is evident, without a detailed analysis of these 

 results, that many features beside hydrogen ion conc;ntratio.-i are 

 involved. 



All of the foregoing tests had as their chief purpose the deter- 

 mination of the reactions of plasmatic constituents and the experi- 

 ments were extended to include the swellings of a biocolloid includ- 

 ing both pentosans and gelatine with the addition of salis, but 

 without the third colloidal component, the soaps, which we now have 

 ample reason to believe play a very important part in the mechanism 

 of living matter. A mixture of gelatine 3 parts and agar 2 parts 

 was made in the usual manner with the addition of salts as in the 

 preparations of agar and of gelatine separately. The increases 

 when h^'drated in various solutions were as noted in Table VIIL 



TABLE VIIL 



The more prominent reactions are those of the gelatine element 

 as would be expected in accordance with which the highest concen- 

 tration is in the most concentrated solution of the acid. It is notable 

 that as in the gelatine-agar salt-free plate depression occurred in 

 acid at PH 3 and that at PH 4.2 the swelling was still below that of 

 water. Practically applied to the living cell this would mean that 

 hydration lessened with increasing acidity to the region of PH 3 

 beyond which the active cell would rarely go. Sodium and calcium 

 exerted similar effects, but the swelling in potassium at o.oooi M 

 was equivalent to that in water while at o.ooi M it was greater. A 

 review of the results presented in this paper would show many 

 special results from the action of this salt. 



The recently published results of experiments upon the coagu- 



