Introduction. 
397 
as calculated from the boiling point or the cryscopic, and from 
the conductivity determinations, is not nearly as close as in the 
case of aqueous solutions. In many cases the boiling point de¬ 
terminations show practically no dissociation, while the solu¬ 
tion conducts well. It must be remembered, however, that a 
slight amount of dissociation cannot be detected by the boiling 
point method; and where the conductivity is slight, the disso¬ 
ciation might be sufficient to account for it. However, this 
difficulty would not be experienced in solutions that conduct 
well. Since these methods are used to determine the degree of 
dissociation and the results show so slight an agreement in non- 
aqueous solutions, it seems but proper to ask which of these 
methods shows the correct degree of dissociation; and one might 
further ask which of the methods is a measure of the dissocia¬ 
tive power of the solvent. 
A number of auxiliary theories have been advanced to explain 
many of the facts observed in ■ relation to the conductivity of 
non-aqueous solutions. Nernst 1 calls attention to the fact that 
solvents which conduct electricity have a high specific inductive 
capacity. Briihl 2 concludes that the dissociative power of solv¬ 
ents is dependent upon spare valences; that is, the solvents 
that yield solutions which conduct, are unsaturated compounds. 
Dutoit and Aston 3 claim that only those solvents the molecules 
of which are polymerized, yield conducting solutions. Abegg 
points out that even these theories are not sufficient to explain 
satisfactorily the phenomenon of the electrical conductivity of 
non-aqueous solutions. These theories will be discussed more 
fully subsequently. 
In face of the data that have been collected, and in view of 
the fact that such a large number of chemists to-day do not ac¬ 
cept the electrolytic dissociation theory as applied to aqueous 
solutions, one may well hesitate to apply this theory to non- 
aqueous solutions, until there is a sufficiently firm experimental 
basis to justify it. The chief object of this investigation is 
1 Zeit. phys. Chem. 14, 622; 1891. 
2 Zeit. phys. Chem. 18, 514; 1895; 27, 317; 1898; Ber. Chem. Ges ., 
Berlin 30,162; 1897. 
3 Comptes rendus , 125, 240; 1897. 
