MABERY. — THE COMPOSITION OF PETROLEUM. 587 



60°, 0.8341 70°, 0.8320 80°, 0.8310 



The oil was agitated several times with concentrated sulphuric acid 

 until the acid was not much colored, and washed with sodic hydrate and 

 water, and finally with salt brine. On account of the high specific 

 gravity of the oil some heavy solution such as brine or calcic chloride 

 was necessary to separate the water and oil. The oil was dried for 

 examination over calcic chloride and metallic sodium. 



A combustion of the oil gave the following percentages of carbon and 

 hydrogen : — 



0.1508 grm. of the oil gave 0.4711 grms. C0 2 and 0.1945 grm. H 2 0. 



A part of the carbonic dioxide was evidently lost, but the results point 

 to the series C n H 2n , which represents the composition of the oil, much the 

 larger part of the distillate. 



A portion of the distillate was cooled to —10°, and filtered cold to 

 separate the crystalline solid. The solubility of the solid hydrocarbon 

 seemed to diminish rapidly with lower temperatures, consequently a 

 small proportion of the solid remains in the oil below — 10°. After 

 pressing and crystallizing from ether and alcohol, the solid melted at 45°. 

 Krafft's hydrocarbon, C 23 H 48 , melted at 47°. 7. Two determinations of 

 its specific gravity at 60° gave (1) 0.7894, (2) 0.7900. 



A combustion of the solid gave results for the series C n H 2n+2 : — 



0.1515 grm. of the substance gave 0.4710 grm. C0 2 and 0.1989 grm. H 2 0. 



Calculated for C^H^. Found. 



C 85.20 85.06 



H 14.80 14.64 



» 



A determination of its molecular weight at the boiling point of benzol 

 was made : — 



1.1208 grm. of the substance and 23.08 grms. benzol gave a rise of 

 0°,412. 



Calculated for C^H^. Found. 



324 327 



