JACQUES L. -;B 



217 



with the increasing, hydrogen ion conct nt'^tion reaching a maximum 

 at pH 3.6 or 3.0 respectively, and tha tl^he rate of diffusion falls 

 again with a further increase in the ' Fdrogen ion concentration. 

 m/256 Na2S04 shows little "attraction" *)r water, and m/128 cane 

 sugar practically none. 



LS 2D 22 24 2.6 2S 3.0 3.2 3.4 3.6 3.8 4.0 42 44 46 4Q 5.0 



Fig. 2. Influence of hydrogen ion concentration on initial rate of diffusion 

 of liquid from a solution of HNO3 through a gelatin-coated collodion membrane 

 into a m/128 solution of cane sugar, m/256 NaCl, CaClo, CeCla, or NaaSOi of the 

 same hydrogen ion concentration. Abscissa) are the pH; ordinates, rise of level 

 of liquid in manometer connected with the salt solution, after 1 hour. Water 

 negatively charged. 



The writer has recently measured the potential differences between 

 the inside salt solution and the outside solution at the end of an hour 

 with the aid of a Compton electrometer (calomel electrodes with 



