MABERY. — COMPOSITION OF PETROLEUM. 281 



tion of constituents of the crude oil. It is therefore possible to continue 

 the distillation of the hydrocarbons even as high as tridekanaphtene 

 under atmospheric pressure after the first distillation. In continuing the 

 distillation, 35 grams collected at 230°-232°, specific gravity 0.8511. 

 After purification with fuming sulphuric acid it gave as its specific grav- 

 ity 0.8134 at 20°. A combustion gave the following results : — 



0.1511 grm. of the oil gave 0.4733 grm. C0 2 and 0.1937 grm. H 2 0. 



Calculated for C 13 H 26 . Found. 



C 85.70 85.41 



H 14.30 14.24 



This formula was also verified by a determination of its- molecular 

 weisrht : — 



1.2712 grm. of the oil and 25.24 grms. benzol gave a depression of 1°.370. 



Calculated for C 13 H 26 . Found. 



182 180 



A determination of the index of refraction gave 1.4745, and the molec- 

 ular refraction 60.254 ; calculated for C 13 H 2G , 59.839. 



Tetradekanaphtene, C 14 H 28 . 



A considerable quantity of distillate collected at 144°-146°, which 

 gave as its specific gravity before purification 0.8428, and after purifica- 

 tion 0.8154. A combustion gave percentages of carbon and hydrogen 

 required for the formula C^H^. 



0.1462 grm. of the oil gave 0.4600 grm. C0 2 and 0.1824 grm. H 2 0. 



Calculated for C,,!!^. Found. 



C 85.70 85.81 



H 14.30 13.87 



A determination of molecular weight at the freezing point gave a value 

 required for tetradekanaphtene : — 



1.3356 grm. of the oil and 24.22 grms. benzol gave adepression of 1°.394. 



Calculated for C 14 H 23 . Found. 



196 194 



The index of refraction of this hydrocarbon was found to be 1.4423, 

 and the molecular refraction 63.75 ; required for C 14 H 2 8, 64.44. 



