36 



WOOD TURPENTINES. 



PRODUCTS OF DISTILLATION. 



The analyses of the products obtained from the distillation of 

 crude turpentine No. 1 are shown in figures 23, 24, and 25. 



HEADS. 



The heads (fig. 23) vary greatly in composition, and approx- 

 imately the first 70 per cent have higher indices of refraction, and 



125 130 135 140 145 150 155 160 

 O .86 .67 .88 .89 .90 .91 .92 .93 

 O 1464 1-466 U68 1470 1.472 L474 1.476 U4.78 



FIG. 23. Boiling point, specific 

 gravity, and index of refraction 

 curves for " heads " obtained in 

 refining of crude turpentine No. 1. 



160 165 170 175 180 185 190 195 

 O .86 n 6 9 30 .91 .92 .93 

 1468 1470 L472 UT4. U76 U78 U80 



FIG. 24. Boiling point, specific 

 gravity, and index of refraction 

 curves for " hearts " obtained in 

 refining of crude turpentine 

 No. 1. 



lower boiling points, than the first fraction of the hearts; this por- 

 tion of the distillate also had a darker color and more disagreeable 

 odor than the fractions above 70 per cent. That portion above 70 

 per cent could well be included in the hearts without affecting the 

 properties of the latter, but probably it is not possible to separate 

 completely so small an amount of heads as were present in the crude, 

 2.5 to 3.0 per cent, without removing some of the hearts at the same 

 time. 1 



1 The heads, on account of the method of their production, could not contain any 

 ieavy oils, and the higher physical properties of the residue in this analysis (and in the 

 analyses of all the other heads) must be due to polymerization during the distillation 

 (see p. 26). 



