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50 MABERY—THE COMPOSITION OF PETROLEUM.  [April3, 
I have a large amount of unpublished data on the sulphur and 
nitrogen compounds in petroleum. Although I have had the sul- 
phur compounds under examination for nineteen years, I am not 
yet sure as to the form of the higher series. In a paper presented 
to the New York Section of the Society of Chemical Industry two 
years ago, and published in the Soctety Journad, a brief account of 
the sulphur and nitrogen compounds was given. It was explained 
that these bodies are members of a series C,H,,S, and that they 
oxidize into sulphones and very readily into sulphuric acid. These 
bodies are doubtless ring compounds, as was then suggested, similar 
to the thiophenes. 
California petroleum contains a larger proportion of nitrogen 
base than any other, so faras known. Two per cent. of nitrogen, 
the amount contained in several specimens of crude oils examined, 
corresponds to twenty or twenty-five per cent. of the basic oils, or 
about one-quarter of the crude oil consists of the nitrogen com- 
pounds. In structure these bodies are tetra- or octohydro-ring 
compounds in homologous series. The tetrahydro-condition is 
shown by their instability. 
It is, therefore, apparent that a similar condition of instability 
prevails in the methylenes, and in the sulphur and nitrogen com- 
pounds from heavy petroleum. The sulphur and nitrogen bodies 
are found in considerable quantities only in such petroleum as is 
mainly composed of the methylenes or series poorer in hydrogen. 
Another interesting series of bodies found in California, but not 
in Eastern oils, at least to the same extent, are the phenols, which 
are present in considerable quantities in some of the California oil. 
NATURAL FORMATION OF PETROLEUM. 
Muchas has been said on this attractive subject, a broader knowl- 
edge of facts is necessary before definite conclusions can be 
reached. What is known forms the basis for only one explanation 
concerning the formation of petroleum, and that is that it was 
formed from vegetable or animal matter by slow decay or breaking 
down from the complex forms of vegetable or animal life under 
the influence of natural forces, with no great elevation in tempera- 
ture such as is necessary for distillation. 
Mendelejeff's theory of the formation from carbides at high tem- 
peratures, recently asserted with greater force on the basis of 
