( 64 ) 



phase and solid phases, hut hardly ever with regard to tlie equilibria 

 between liquid and vapour. 



I, therefore, proposed to further investigate this relation in the 

 case of vapour pressure- and boiling-point curves on a series of 



examples in which the nature and the degree of the complex mole- 

 cules varied, in order to obtain a more definite idea of the changes 

 which these curves undergo as compared with the simple case in 

 which the binary system consists only of two kinds of molecules. 



Such an example is furnished bj' the system sulphur-chlorine, the 

 boiling-point curves of which are given in the accompanying figure, 

 which is constructed from determinations made by Mr. Atex. 



