29 



(2) The graphical method of expressing the data gives a ready 

 means of interpreting the results and comparing various turpentines. 



(3) The large amount of data obtained makes the results very 

 reliable. 



(4) The low temperature at which the distillation is carried out 

 reduces the danger of alteration of the sample during the analysis. 



(5) The distillation is similar to certain technical distilling proc- 

 esses which have been found to give excellent results in practice, and 

 suggests the possible results of applying such methods to the refining 

 of turpentines. 



Approved: 



JAMES WILSON, Secretary. 



WASHINGTON, D. C., May 8, 1908. 



[Cir. 152] 



O 



