467 



The author, in conclusion, calls attention to the importance of 

 considering the chemical character in comparing the boiling-points 

 of the volatile organic bases, and shows the necessity of distinguish- 

 ing between the primary, secondary, and tertiary monamines in order 

 to exhibit constant differences of boiling-point for this class of sub- 

 stances. He discusses the boiling-points of the several bases, 

 CnH^-sN and C n H w + 3 N, and points out how in many cases the 

 particular class to which a base belongs may be ascertained by the 

 determination of the boiling-point. 



The comprehensive recognition of definite relations between com- 

 position and boiling-point is for the present chiefly limited to organic 

 compounds. But for the majority of these compounds, and indeed 

 for the most important ones, this relation assumes the form of a 

 simple law, which, more especially for the monatomic alcohols, 

 C w H m O 2 , for the monobasic acids, C w H m O 4 , and for the compound 

 ethers generated by the union of the two previous classes, is proved 

 in the most general manner ; so much so, indeed, that in many cases 

 the determination of the boiling-point furnishes most material assist- 

 ance in fixing the true position and character of a compound. 



The author points out more especially that the simplest and most 

 comprehensive relations have been recognized for those classes of 

 organic compounds which have been longest known and most accu- 

 rately investigated, and that even for those classes the generality and 

 simplicity of the relation, on account of numerous boiling-points in- 

 correctly observed at an earlier date, appeared in the commencement 

 doubtful, and could be more fully acknowledged only after a consi- 

 derable number of new determinations. Thus he considers himself 

 justified in hoping that also in other classes of compounds, in which 

 simple and comprehensive relations have not hitherto been traced, 

 these relations will become perceptible as soon as the verification of 

 the boiling-points of terms already known, and the examination of 

 new terms, shall have laid a broader foundation for our conclusions. 



