igo4] Mills — Molecular Attraction. 101 



this subject. This paper presents additional evidence in 

 favor of the theory, and it is the intention of the author to 

 extend the work to the ten esters for which measurements 

 have been made by Prof. Young-. The "other assumptions of 

 doubtful validity" upon which the present theory is based, 

 referred to in that review, were mentioned in the original 

 paper as they are in this (here they are numbered, however, 

 so that he who runs may read), without attempt at proof. 

 True equations are seldom deduced from wrong- assumptions, 

 and if we can establish the truth of the equation the assump- 

 tions will probably be admitted by those who now doubt their 

 truth. All of the assumptions made, except possibly the law 

 of attraction assumed, are, we are inclined to believe, reg-arded 

 favorably by scientists on other grounds. Concerning- the 

 statement made in that review that "the author does not 

 point out the simple relations between the densities of vapor 

 and liquid, and the difference in their specific heats, which 

 would be the direct consequence of his equations," we would 

 say that we are of course aware that the equations that we 

 have deduced can be combined with certain other thermody- 

 namical, empirical and rational equations, so as to produce 

 certain relations. (See for instance, equation 13 of this 

 paper, which equation is similar to the relation, p = bt — a, 

 of Professors Ramsay and Young-.) The theory itself here 

 given is capable of further direct and very promising- applica- 

 tion. The author hopes shortly to complete and publish a 

 paper calling attention to some of these extensions of the 

 theory. 



For the measurements used we are indebted almost entirely 

 to the labors of Profs. Ramsay and Young-, and Prof. Young. 

 After months of laborious acquaintance with these measure- 

 ments we cannot conclude this paper without giving expres- 

 sion to the sincere admiration excited by the accuracy and 

 completeness of the data they have furnished. And we would 

 express a thanks, heartfelt, and echoed doubtless by hundreds 

 of workers elsewhere, for their labors. 



