150 DISCUSSION OF EVIDENCE. 



as solvent, the rise in its boiling-point produced by a given amount 

 of dissolved substance would be larger than if all the alcohol were 

 playing the part of solvent. 



Further, if the dissolved substance combines with a part of the 

 alcohol, the more concentrated the solution the greater the total 

 amount of alcohol held in combination. This would explain the 

 increase in the molecular rise in the boiling-point with increase in tha 

 concentration of the solution. This suggestion of combination between 

 a part of the solvent and the dissolved substance explains the facts 

 in alcoholic solutions just as well as the hydrate theory explains the 

 facts in aqueous solutions. 



The work of Jones and Getman in solutions in ethyl alcohol as the 

 solvent was extended by Jones and McMaster to methyl alcohol. 

 They also extended the work in ethyl alcohol as the solvent. They 

 repeated a part of the work of Jones and Getman in ethyl alcohol and 

 obtained results of the same general character as had been found by 

 the earlier workers. 



They used the boiling-point method with methyl alcohol as the 

 solvent, and the chloride, bromide, and nitrate of lithium as the dis- 

 solved salts. The molecular rise in the boiling-point, even in the most 

 dilute solutions, was greater than could be accounted for by the disso- 

 ciation. This is, of course, entirely incapable of accounting for the 

 increase in the molecular rise with increase in the concentration of the 

 solution, which manifests itself in the case of every salt studied in this 

 solvent, dissociation decreasing with increase in concentration, which 

 would tend to diminish the molecular rise in the boiling-point. 



The magnitude of the molecular rise in the most concentrated solu- 

 tions is very large indeed. It is almost twice the boiling-point constant, 

 or normal molecular rise for this solvent; and the dissociation of such 

 solutions is certainly not more than 25 to 30 per cent, and probably 

 less than this value. 



We interpreted these results as we did those in ethyl alcohol as the 

 solvent there is combination between a part of the alcohol present 

 and the dissolved substance, forming methyl alcoholates. As the con- 

 centration increases, more and more alcohol is held in combination 

 by the dissolved substance; consequently, there is an increase in the 

 molecular rise of the boiling-point. 



It thus seems that evidence was furnished of combination between 

 methyl alcohol and the dissolved substance, on the one hand, and 

 ethyl alcohol and the dissolved substance on the other. As we shall 

 see later, evidence has been obtained of combination between acetone 

 and substances dissolved in it; and other solvents have been and are 

 being brought within the scope of this work. 



In every case thus far investigated there seems to be good evidence 

 in favor of the view that there is combination between the dissolved 



