﻿596 



Mr. T. Carlton Sutton on the 



Chlorobenzene. 





1 

 Mill's Constant. 



Calculated by Biot's formula. 



Calculated by 



Temperature. 



, * s 



Applebey's 





Eecalc. from 



formula. 





Calc. 1905. revised data 1909. 

 79-46 799 





130° C 



85-9 



160° 



80-83 80-9 



85-6 



190° 



81-34 81-5 



84-5 



220° 



81-84 82-2 



83-9 



240° 



83-06 82-8 



84-0 



270° 



84-93 82-5 



85-4 



Bromobenzene. 



100° C 



56-93 



59-8 



150° 



54-10 54-6 



59-6 



180° 



54-98 55-0 



59-6 



210° 



55-9 55-7 



59-2 



230° 



56-25 56-0 



587 



250° 



56-44 55-8 



58-8 



260° 



56-92 56-1 



58-7 



270° 



57-15 562 



58-6 



Iodobenzene. 



190° C 



41-87 42-9 



45-9 



220° 



43-64 43-5 



46-0 



250° 



44-38 43-6 



465 



270° 



45-10 43-2 



469 



Mills has twice calculated the values of fi' , employing 

 Biot's formula to represent the connexion between saturation- 

 pressure and temperature. The calculations of 1905 show 

 irregularities in the values obtained in these same cases, 

 chlorobenzene, bromobenzene, and iodobenzene. The recal- 

 culations of 1909, based on Young's revised data, show 

 irregularities that are smaller, but are still much greater 

 than those given by other substances. When the modified 

 van der Waals' equation is used, these irregularities still 

 occur. It will be seen that they are smaller than in the 

 previous cases, though only slightly so. What seems more 

 important is the fact that, in general, maximum values 

 obtained by means of Biot's formula correspond to minimum 

 values obtained by the van der Waals' relation, and so on. 

 This suggests that the error is due to some change in the 

 liquids not accounted for by either of the formulae. 



It seems therefore that in the case of these non-associated 



