Chemistry of California Petroleum--Prutztnan. 241 
paraffins and olefins in the heavier portions. The petro- 
leums of the Caucasus are stated to consist principally of 
the naphthene group, while some German petroleums are. 
stated to contain notable proportions of h}'drocarbons of 
the benzine series. A^arious observerst have found in Cali- 
fornia petroleum all of these constituents, and as a discus- 
sion of this very abstract question would be out of place 
here, reference is given to the original papers for justifica- 
tion of the statement that most California petroleums, or 
rather their distillation products, contain hydrocarbons of 
all the following series : paraffins, olefins, probably acety- 
lenes and other highly unsaturated compounds, naphthenes 
(cycloparaffins), and aromatic (benzene) compounds. 
A very few of the local oils give a light distillate which 
appears, from its specific gravity and other physical proper- 
ties, to consist largely of paraffins, but the major part of 
our oils give a light distillate which is much heavier than a 
mixture of paraffins of corresponding boiling point could 
be. By acting on these gasolines and kerosenes, the ole- 
fins may be removed, and as sulphuric acid used in excess 
absorbs but a very small proportion, it may be assumed 
that the olefins are not present in large quantity. After 
rigorous treatment with sulphuric acid, a varying but large 
proportion of the oil is acted on by nitric acid, forming a 
stable nitro-compound, and leaving a residue which can not 
be further alTected. This residue is very much lighter than 
the original oil, and from its resistance to all reagents prob- 
ably consists of pure paraffins. The portion removed by 
nitric acid may be either benzenes or naphthenes. or both. 
It is probable that the latter is the case, though the per- 
centage of benzenes must usually be quite small, as the 
gravity of benzene proper (C^H^) is about 28° Be., and 
the boiling point 80°, while the grayity of local petroleum, 
distillate boiling at this temperature is well above 70° Be. 
tConsult— 
A. S. Cooper. Mining and Scientific Press, 82-123; Bulletin 16, State Min- 
ing Bureau. 
Felix Lengfeld and Edmund O'Neill. Amer. Chem. Jour., 15-19. 
Charles F. Mabery. Am. Chem. Jour., 19-796; Am. Chem. Jour., 25- 
253; Jour. See. Chem. Ind., 19-502. 
S. F. Peckham. Am. Jour. Science., 3-48-250; Science, 23-74. 
Clinton Richardson. Jour. Soc. Chem. Ind., 19-123. 
Frederick Salathe. 13th Report of the State Mineralogist. 
