156 



It is also possible to tell the apiiroximate composition of both liciuid and 

 vapor (or distillate) at any moment during the distillation of a mixture. 

 This application has proved interesting in interpreting the behavior of alcohol- 

 water mixtures during distillation and partial condensation in the writer's 

 laboratory classes. 



It is the intention to continue the experiments by examining mixtures 

 containing over 92 per cent, of alcohol; the observations will require greater 

 accuracy, and a differential thermometer graduated in hundredths of a degree 

 will be employed. 



Purdue University, 



Lafayette, Ind. 



