THE number of NATURE which appeared on January 30 contains an abstract of a paper by L. Kahlenberg entitled 'The Theory of Electrolytic Dissociation as viewed in the Light of Facts recently Ascertained.' In the paper referred to is a kind of summary of observations which have been made on non-aqueous solutions, from the consideration of which the author draws the conclusion that the electrolytic dissociation theory is untenable in the case of non-aqueous solutions.