MABERY. —THE COMPOSITION OF PETROLEUM. 593 



A combustion gave the following percentages of carbon and hy- 

 drogen : — 



0.1508 grm. of the substance gave 0.4703 grm. C0 2 and 0.2032 grra. 

 H 2 0. 



Calculated for C 28 U"38- Found. 



C 85.28 85.07 



H 14.72 14.97 



The molecular weight at the boiling point of benzol corresponded 

 to the formula C 2s Il5 8 . 



3.070 grms. of the solid hydrocarbon and 26.21 grms. benzol gave a 

 depression of 0°.7538. 



Calculated for C^llsg. Found. 



394 399 



The very thick oil separated by filtration gave as its specific gravity 

 at 20, 0.8G94. A combustion gave percentages of carbon and hydrogen 

 required for the series, C n II 2n _ 2 . 



0.1500 grm. of the oil gave 0.4729 grm. CO, and 0.1836 grm. H.,0. 



Calculated for Found. 



Casing C ;e II-n Cj g (l r ^. 



C 85.28 85.70 86.02 85.96 



H 14.72 14.30 13.98 13.60 



The molecular weight was found at the boiling point of benzol. 



I. 2.6792 grms. of the oil and 29.85 grm. benzol gave a rise of 0°.5826. 

 II. 1.9196 grms. of the oil and 27.98 grm. benzol gave a rise of 0°.4459. 



Calculated for Found. 



C 28 II r4 . I II. 



392 396 394.4 



The index of refraction was found to be 1.480, which corresponds to 

 the molecular refractions : — 



Calculated for C^Hsg. Found. 



127 126.78 



It will be observed that the two liquid hydrocarbons last described 

 have been shown to belong to a series C D II 2a _ 2 . Results already ob- 

 vol. xxxvii. — 38 



