ANALYSIS, REFINING, AND COMPOSITION. 



23 



with and without water and the specific gravity and index of refrac- 

 tion were determined at regular intervals; in both cases a well-cooled 

 reflux condenser was used so that the loss was negligible. The effects 

 of boiling under these two sets of conditions are shown graphically 

 in figure 9. By boiling with water at a temperature of about J)i C., 

 the specific gravity of the turpentine was increased very slightly the 

 first hour and after that decreased very slightly every hour until the 

 boiling was stopped. By the boiling without the presence of water 

 at a temperature of about 162 C., the gravity increased at the rate 



.881 .882 .883 SPECIFIC GEAVlTY 

 MO.OFEEF. ATI5C. L4155 -U760 



AT I5C. 



FIG. 9. Effect of boiling with water 

 (steam distillation) and of boiling 

 without water (direct distillation) 

 on the specific gravity and index of 

 refraction of crude wood turpentine. 



.bkA .865 5PCCFIC ee&VITY ATI5C 



L4"7lO U7I5 IND. OF- PER AT I5C. 



FIG. 10. Effect of boiling with 

 water (steam distillation) and of 

 boiling without water (direct dis- 

 tillation on the specific gravity 

 and index of refraction of refined 

 wood turpentine. 



of 0.00045 per hour for the first two hours, and then at a njuch slower 

 rate. The index of refraction was increased considerably by both 

 methods of boiling during the first two hours and then more slowly. 



BEFINED WOOD TURPENTINE. 



The results from a similar series of experiments on another turpen- 

 tine (turpentine No. 5, the analysis of which is shown in fig. 7) are 

 expressed graphically in figure 10. Here the changes in the physical 

 properties due to methods of boiling are less than were shown in 



