438 DR. C. H. LEES ON THE THERMAL CONDUCTIVITIES OP SOLIDS 



Xx 



*s 



<K 



20% 





#t 



M 



40% 60% 



Constitution. 



MrP . 



60% 



5O 



2-O 



1-0 



A reference to the values obtained for the thermal conductivities of solutions of a 

 gas or a solid in water, will show that the above law does not apply to cases in which 

 one constituent of the mixture changes its physical state on mixing. Further work 

 is necessary before any law can be stated, but it seems probable that if the thermal 

 conductivity of the gas or solid when liquefied were known and used as that of the 

 material entering into solution, the above law would be found to cover solution as 

 well as physical mixture. 



PAET V. CHANGE OF CONDUCTIVITIES OF MIXTURES WITH TEMPERATUEE. 



In order to determine the effect of temperature on the thermal conductivities ot 

 mixtures, experiments were made on several of the 50 per cent, mixtures of liquids 

 mentioned in the preceding section. They were carried out with the enclosed 

 apparatus, fig. 11, p. 419. The observations and results are given in the following 

 tables and curves : 



