258 PROCEEDINGS OF THE AMERICAN ACADEMY. 



illation to avoid loss in transferring to the combustion tube, and as will 

 appear later, the highest temperature that the hardest tube will stand is 

 necessary lor complete combustion. These results seem to indicate that 

 tli«- nil was a mixture of hexane and bexamethylene. The slight change 

 in specific gravitj after tr< atment with tinning sulphuric acid and potassic 

 hydrate shows that the benzol bad been almost completely removed. 

 The fractions at 68 appear to be the last in California oil containing 

 members <>t the series C II 8 . Since .small quantities of distillates 

 collected in the viciuitj of 60 . 38 .and in one specimen at 30°, it is 

 inc hable that the very light gasoline from California oil has the same 

 composition a- that from Pennsylvania oil. 



Tin- specific gravity of hexane. 0.6630 at lb' . and of bexamethylene, 

 0.690, also indicate that the fraction t.b°-70 o is a mixture of these two 

 hydrocarbons. 



lit itami.tiiylkm:. C 7 1I u . 



The distillate collected at 9G°-98° amounted to fifty grams. Before 

 purification it gave as it< specific gravity 0.7499, and after purification, 

 H.7 US. The specific gravity of heptane boiling at this point is 0.64 tO 

 r2" ..")). Beilstein and Kurbatoff gave 0.742 at 18° as the specific grav- 

 ity of beptanaphtene. A combustion gave the following percentages of 

 carbon and hydrogen : — 



(Mil:; grm. of the purified oil gave 0.4142 grm. C0 2 and 0.1814 



A determination of the vapor density of the fraction 9G°-98° by col- 

 lecting the vap..r over memirv gave a value corresponding to the molec- 

 ular weight of heptamethylene. The determination was made by the 

 method of Y. Meyer, in vacuo, essentially according to the modification 

 of Lunge and Neuberg:* — 



l.i| grm. of the ,,il gave 22.9 C.C. under a tension of 373 mm. and 

 at 2 1 . 



rc : ii u . Pound 



3.40 8.40 



• Ber. deutach. Gesell., 1891, 7-J'.'. 



