158 PROCEEDINGS OF THE AMERICAN ACADEMY. 



0.1610 gram of the oil gave 0.5057 gram CO2, and 0.1989 gram H2O. 



C 85.67 



H 13.72 



Before treatment with the acid, a determination of specific gravity at 

 20° gave 0.7785. After purification with the acid the specific gravity 

 was diminished to 0.7572, nearly the same value as that found in the cor- 

 responding fraction of Ohio oil. The penetrating odor of the crude dis- 

 tillate, resembling that of the aromatic hydrocarbons, disappeared entirely 

 after treatment with the fuming acid, and the purified oil gave only the 

 faint characteristic odor of the petroleum hydrocarbons C„H2„+2- The 

 acid was blackened and gave ofE much sulphurous acid. 30 grams gave 

 by this treatment 23.4 grams of the purified oil with a loss of 22 per cent. 

 It is interesting to note the higher specific gravity of the unpurified dis- 

 tillate 163°-164° in all these oils — Pennsylvania, Canadian, and Ohio 

 — than that of the higher distillate, 174°. This clearly indicates a larger 

 percentage of mesitylene and perliaps of decanaphtene. The difficulty 

 in removing entirely the heavier body would seem to indicate a trace of 

 the latter. 



After the last distillation, the oil was again treated with the fuming 

 acid and dried over sodium for analysis : — 



0.1723 gram of the oil gave 0.5358 gram COo, and 0.2304 gram HoO. 



Found. 



84.82 

 14.85 



The oil was again subjected to the action of the acid and analyzed: — 



0.1561 gram of the oil gave 0.4847 gram CO., and 0.2127 gram HoO. 



C 84.67 



H 15.14 



The slight change in the percentages of carbon and hydrogen evidently 

 shows the presence of a heavy body that is but slowly affected by the 

 acid. This impurity cannot be mesitylene, since this hydrocarbon dissolves 

 readily in the fuming acid. Another portion of the crude distillate was 

 next vigorously agitated with a mixture of nitric and sulphuric acids, 

 allowing the temperature to rise spontaneously nearly to 100°. As soon 

 as the principal action ceased, the mixture cooled and an oily nitro body 



