MABERY. — ON THE COMPOSITION OF PETROLEUM. 333 



Calculated for C^jIIij- Found. 



101.7 162.1 



A fraction that collected in considerable quantity at 2G3°-2G5°, 

 3U mm., after treatment with sulphuric acid in gasoline solution and 

 nitration at— 10°, gave as its specific gravity at 20°, 0.8864. A com- 

 bustion gave the following percentages of carbon and hydrogen : 



0.1470 gram of the oil gave 0.4670 gram CO2 and 0.1752 gram II2O. 



Calculated for CojII^j. Found. 



C 86.75 86.68 



H 13.25 13.32 



The molecular weight of this hydrocarbon was not determined for the 

 same reasons as the piecediug. A determination of the index of refrac- 

 tion gave 1.4802, corresponding to the following molecular refraction: 



Calculated for C24II44. Found. 



106.5 106.3 



A fraction collected in quantity of 40 grams at 275°-278°, 30 mm., 

 that was filtered at — 10°, and the thick viscous oil purified with acid. 

 It gave as its specific gravity at 20°, 0.8912. A combustion gave per- 

 centages of carbon and hydrogen required for the series C„H2„_4: 



0.1547 gram of the oil gave 0.4914 gram CO., and 0.1814 gram H.^O. 



The molecular weight of this hydrocarbon was not determined. The 

 index of refraction was found to be 1.4810, and the molecular refraction 

 as follows : 



Calculated for C2:iH4g. Found. 



110.9 110.5 



"While the precise formulas of the last three hydrocarbons are not 

 determined with as complete data as those preceding, it is evident that 

 the determinations establish the series CnH2n-4' 



Ohio petroleum is therefore composed chiefly of the series CnHsn+a? 

 CnHo,,, C„H2n-2? ^ud the series CnH.,„_4. It resembles Pennsylvania 

 petroleum in the large proportion of solid paraflRne hydrocarbons. But 

 the greater portion of the portions boiling above 216° consists of the 



