1910-11.] Study of the Constitution of Calomel Vapour. 
185 
bulblet apparatus,* gave results in which the agreement was almost as 
good (average divergence —3*3 mm.). 
The results show, therefore, (1) that the vapour is composed wholly of 
mercury and corrosive sublimate, HgCl and Hg 2 Cl 2 being alike absent ; 
(2) that calomel dissolves in mercury with a molecular weight corre- 
sponding to the formula HgCl ; (3) that the isoteniscope may he used 
in the quantitative investigation of chemical problems. 
The University of Chicago, 
June 1910. 
* Proceedings , vol. xxx. p. 437. 
{Issued separately December 29, 1910.) 
