228 Prof. L. Kahlenberg on the 



unjustifiable. This becomes particularly apparent from the 

 researches of Patten *, and recently C. J. Reed f has pre- 

 sented the subject in a very able manner before the American 

 Electrochemical Society. The Kohlrausch law of the additive 

 character of the molecular conductivity of solutions at very 

 high dilutions holds at best only for a limited class of aqueous 

 solutions : it is, of course, founded upon the calculations of 

 molecular conductivity, which, it has been pointed out, are 

 objectionable. The whole matter of the calculation of so-called 

 molecular conductivities of solutions at different concentrations 

 being open to serious objection, it is not at all' surprising that 

 such a relation between electrical conductivity of solutions 

 and their freezing-points or boiling-points as is claimed by 

 the theory of electrolytic dissociation does not exist. 



Faraday continually emphasized the view that in electro- 

 lysis the products do not appear at the electrodes because 

 they are attracted there by the latter. His idea was that the 

 products are ejected at the electrodes by the electrical energy 

 acting as an axis of force driving the products out in the two 

 directions, the electrodes serving simply as doors. In a special 

 paper on electrochemical theories, to which the reader is 

 referred J, I have entered somewhat more fully into a consi- 

 deration of theories of electrolysis. 



During the past year I have been engaged in osmotic expe- 

 riments, which included both qualitative investigations and 

 quantitative measurements of osmotic pressures. The latter 

 determinations were made with semi-permeable membranes. 

 The details of the apparatus used, and the results obtained, 

 will soon be published in a special paper. Here I would like 

 to state, however, that it was found that whether osmosis will 

 take place or not depends on the nature of the membrane 

 and the liquids bathing it ; and the direction and magnitude 

 of the osmotic pressure is also dependent upon the nature of 

 the membrane and the liquids in contact with it. The quan- 

 titative measurements of osmotic pressure made with semi- 

 permeable membranes yielded results which are not such as 

 the gas laws require. It is especially noteworthy that cases 

 have been found in which at constant temperature the osmotic 

 pressure diminishes very rapidly as the solution is diluted, 

 becoming practically nil for solutions about one-twentieth 

 normal. The results of the osmotic experiments are readily 

 explained by the view that the membrane imbibes or unites 

 with the solvent, because of the affinity existing betsveen them, 



* Journ. phys. Chem. vi. p. 5-54 (1904). 



t Trans. Amer. Electrochem. Soc. v. p. 103 (1004). 



X Trans. Amer. Electrochem. Soc. i. p. 119(1902). 





