JACQUES LOEB 



281 



gelatinate. It may be well to point out this analogy by making the 

 experimental methods in both cases as much ahke as possible. 



To solutions of m/256 Na2S04 were added the same concentrations 

 of salt as in the gelatin experiments; namely, 0, 0.1, 0.2, 0.4, 0.8, 1.6, 

 3.2, 6.4, 12.8, and 25.6 cc. of m/4 salt in 100 cc. of solution. These 

 solutions were put into collodion bags and the latter were put into 

 the solutions of the same salts as those in which the Na2S04 was made 



g 



•55 



■■3 



IS 



180 

 160 

 140 

 120 

 100 



80 



60 

 :g 40 



20 

 



n .TLILJL Ji n. H 



4000 2000 1000 500 250 125 62 



Concentration of alkali added 



Fig. 5. Depressing effect of the addition of alkali to 1 per cent Na gelatinate 

 of pH = 8.4 upon the initial rate of diffusion of water into the gelatin solution. 

 Ca(0H)2 depresses more than KOH. 



up. This means, that when 100 cc. of the solution in the collodion 

 bag were a mixture of m/256 Na2S04 in m/2,000 KCl, the outside 

 solution was m/2,000 KCl (without Na2S04), and so on. This was 

 done to make the experiments in every point like the gelatin experi- 

 ments, in which the outside solution also contained the same concen- 

 tration of salt which was added to the gelatin solution. It was found 

 that the addition of salts and of alkali depresses the initial rate of 



