ON ELECTROLYSIS IN ITS PHYSICAL AND CHEMICAL BEARINGS. 387 



'8. To § 4 you say that the Winiamson-Olausius hypothesis would have been 

 soon abandoned if it had not con-esponded with the fundamental laws of Faraday, 

 Richter, &c. So far as I know, no one has hitherto raised the question ; besides 

 it is of very great importance to deduce various laws from a single point of view. 



' 9. As to law (20), which is still very discussable, I have had no opportunity 

 of going off into digressions in the treatise, but refer to Hittorf and Bleekrode. I 

 treat the whole question as open, and share also the view that the conductivity of 

 these bodies has been proved to be mainly, though not exclusively, due to the 

 presence of saline impurities. One is only able at present to decide matters like 

 this on a chemical basis. 



' With compliments, &c., 



'Syante Aerhenius. 

 ' Wurzburg, November 1886.' 



Viscosity and Conductivity. 



\Tlie following letter from Dr. Akrhekius, though of late date, so directly bears on 

 subjects referred to by Prof. Kohlrausch (p. 343) that it is best inserted noiv. 



0. L.] 



WuRZBUEG : Januarij 4, 1887. 



Some time ago I thought of publishing the numbers given below, which may 

 have a certain amount of interest in elucidating the question as to the connection 

 between conductivity and internal resistance. In discussing the question with 

 Prof. Kohlrausch I have been confirmed in my hypothesis, and, in accordance as 

 much with his desire as with my own, I send the following communication. 



In the subjoined table the names of the solutions examined (all of normal 

 strength) are set forth in the first column ; in the second column the conductivity 

 (\) of these solutions (from Kohlrausch's last memoir) ; and in the third column 

 ihe viscosities (p) determined by myself. The fluids I investigated are identical 

 with the solutions employed by Kohlrausch in his conducti\dty determinations. 

 The numbers for the internal friction are given for 17'6° C, reduced to the 

 internal friction of distilled water at 17'6° as unit. I cannot here describe the 

 method of investigation, but may refer to the paper which I have communicated 

 to Wiedemann's ' Annalen.' . The errors of observation probably do not amount to 

 <)'5 per cent. 



The numbers entered in the fourth column are some further experiments by 

 Kreichgauer, assistant to Prof. Kohlrausch ; they may be in error to the extent of 

 one or two per cent. The number for potassium acetate was not observed directlv, 



c c2 



