278 PROCEEDINGS OF THE AMERICAN ACADEMY. 



The distillates 65°-70° from Torrey, Scott's Hill, and Fresno oils were 

 put together and carefully distilled a number of times in order to separate 

 so far as possible the hydrocarbon boiling at 68° or 69° from other 

 admixtures, and the fraction 68° -69° was thoroughly treated with fum- 

 ing sulphuric acid, warming gently and allowing it to stand with the acid 

 over night. Before treatment the specific gravity at 20° was 0.7005, 

 and after treatment, 0.6929. The following results were obtained by 

 analysis : — 



I. 0.2-122 grm. of the oil gave 0.7596 grm. COo and 0.3234 grm. HoO. 



In this analysis the combustion tube was filled with oxygen before the 

 oil was volatilized, and the temperature was kept as high as the tube 

 would stand. There seems therefore to be little doubt that the hydro- 

 carbon in California petroleum boiling at 68°-69° is composed chiefly 

 of hexamethylene. 



Since small quantities of distillates remained in the vicinity of 90°-91°, 

 it suggested the possibility that isoheptane might form a part of this 

 product. But its high specific gravity, 0.7303 at 20°, isoheptane 0.6819 

 (17°. 5), and the composition showed by analysis, excluded isoheptane in 

 any considerable quantity. 



0.1273 grm. of the oil gave 0.3987 grm. COo and 0.1665 grm. HgO. 



Especial precautions were taken in this analysis to have the tem- 

 perature of the combustion as hot as possible, and the tube was filled 

 with oxygen before the oil volatilized. The proportions of carbon and 

 hydrogen indicating the absence of isoheptane could not have been due 

 to the presence of benzol, since the oil was treated several times with 

 fuming sulphuric acid. The volatile portions of California petroleum, 

 therefore, contain at most very small proportions of the hydrocarbons, 

 C„H2„+2, and these if present consist almost exclusively of members 

 below normal hexane. Further confirmation of these formulae is given 

 by the chlorine derivatives, which will be described in another paper. 



