ORAN L. RABER 537 



Measurements of the conductivity (permeability) were taken at the 

 end of 5, 25, 45, 65, 85, and 105 minutes in the salt solution except in 

 certain solutions (citrate, phosphate, and tartrate) where the resist- 

 ance diminished very rapidly. 



The results are shown in Fig. 1 , the curve for each salt representing 

 an average of ten experiments. The probable error of the mean (as 

 based on Peter's formula) is always under 10 per cent, and for 75 

 per cent of the points is under 5 per cent. 



It will be noted that the effect of these anions upon the increase in 

 permeability as seen at the end of the experiment is in the series I, 

 Br, SCN, CI, NO3, acetate, SO4, tartrate, PO4, citrate. 



This differs from the Hofmeister series in that the effect of SCN is 

 noticeably more than that of the iodide while the two effects were 

 indistinguishable by Hofmeister, and also in that the relative posi- 

 tions of chloride and nitrate are reversed in this work from that 

 found by both Pauli and Hofmeister. That these positions, however, 

 are not invariable has been shown by Hober who obtained so called 

 "transition series" by varying the hydrogen ion concentration^ and 

 the concentration of the salt.^ It may be noted, however, that at the 

 end of the 25, 45, and 65 minute periods, when the disturbance affect- 

 ing the experiment at the start has subsided and before possible 

 disturbing factors due to the purely mechanical deterioration of the 

 tissue have appeared, the position of the nitrate is above that of the 

 chloride. 



It is also seen that there is a distinct grouping into two or three 

 groups. The iodide, bromide, sulfocyanide, chloride, and nitrate 

 behave very similarly, while the acetate, sulfate, tartrate, phosphate, 

 and citrate have a much more striking effect. In order to have solu- 

 tions of the same conductivity as the sea water used, it was found 

 necessary, as already mentioned, to employ different concentrations. 

 But it is also desirable to make a comparison on the basis of the same 

 molecular concentration. Since the concentration of two of the 

 salts was close to 0.52 m and since this is the concentration of sodium 



^ Hober, R., Physikalische Chemie der Zelle und der Gewebe, Leipsic, 4th edi- 

 tion, 1914, 323. 



^ Hober, R., Physikalische Chemie der Zelle und der Gewebe, Leipsic, 4th edi- 

 tion, 1914, 324. 



