ANALYSIS, RKKINJNC, AND COMPOSITION. 



different; they indicate that there are three main constituents of this 

 turpentine sufficiently different in boiling points and other properties 

 so that approximate determinations can be made of the proportion 

 of each, these proportions being about SO per cent of pinene, 15 per 

 cent of dipentene, and 5 per cent of heavy residue. In the distilla- 

 tion by the first two methods the dipentene was not sufficiently well 

 separated from the other constituents so that its presence was sharply 

 indicated, the very slight and very gradual decrease in the specific 

 gravity over the first 80 

 per cent of the distilla- 

 tion being the only sign 

 of the presence of such 

 a substance. 



Another comparison 

 of the results obtained 

 by steam and direct dis- 

 tillation, both through a 

 dephlegmator, is given 

 in figure 8, in this case 

 on a still more complex 

 turpentine. The curves 

 obtained by the direct 

 distillation with a Le 

 Bel-Henninger de- 

 phlegmator indicate 

 that this turpentine is 

 composed of about 11 

 per cent " light oils " 

 (with boiling points be- 

 low those of pinene), 

 about 32 per cent of pi- 

 nene, about 22 per cent 

 of dipentene, and 35 per 

 cent of heavy oils. The 

 separation between the pinene and the dipentene was not very sharply 

 indicated that is, the breaks in the direction of the curves are not 

 very marked but the amount of light oils, of turpentine oils (pinene 

 and dipentene), and of heavy oils are quite accurately determined. 

 In the steam-distillation curves, however, no sharp separation of 

 the turpentine into its constituents are shown; that is, there are no 

 sharp breaks in the curves. The presence of dipentene is not even 

 indicated qualitatively, and the proportion of heavy oils (as in 

 fig. 6) can not be judged within 8 to 12 per cent. 



These examples of the results obtained in the fractionation of three 

 different turpentines by different methods of distillation have shown 



96 97 98 99 BOtLIMS POINT-STEAM DISTILLATION 



SPCCIFIC GEAVITY &f> 7 8 .89 50 .91 .92 .93 



SDeX OF EEFI2ACT1OM 1468 W1O W1Z L4T4 U16 1418 UC 1*82 



FIG. 7. Comparison of fractionation obtained by (1) 

 steam distillation with a Geer dephlegmator, (2) 

 direct distillation with a Le Bel-Henninger dephleg- 

 niator, and (3) direct distillation without a 

 dephlegmator. 



