MABERY. — SULPHUR PETROLEUMS. 7 



Engler looks upon these acids as formed by oxidation of other con- 

 stituents of the crude oil. According to the results of Markownikoff 

 and Ogloblin,* the fraction 7o°-8o° from Caucasus oil contains 0.76 

 per cent of oxj^gen com[)Ounds, and the fraction 220°— 230°, 5.21 per 

 cent. These oxygen compounds are in part acid, in part neutral, and 

 in part phenol. The acids CioHiaCOOH and CnHjiCOOH were ob- 

 tained as colorless oils ; f Markownikoff and Ogloblin regarded these 

 substances as naphtene carboxylic acids. 



Most petroleums have been shown by analysis to contain nitrogen, 

 usually in minute quantities. In distillates from Pennsylvania oil, 

 Beilby t found 0.U8 per cent in the residuum or tar, and 0.375 per cent 

 in the coke. Since the tar was one tenth of the crude oil, the latter 

 contained 0.008 per cent of nitrogen. In crude Russian oil Beilby 

 found 0.05 per cent. Peckham § found in West Virginia oil 0.54 per 

 cent, in Mecca oil, 0.23 per cent, and in California oil, 0.56-1.1 per 

 cent of nitrogen. In Egyptian oil, Kast and Kunkler || reported 0.3 

 per cent of nitrogen, 1.21 per cent of sulphur, and 0.92 per cent of 

 oxygen. Weller IT detected certain alkaloid bases in paraffine oil, and 

 Bandrowski** described a thick, transparent liquid solidifying at 20°, 

 ■which he obtained by agitating Galician oil during several weeks with 

 sulphuric acid. This substance gave a platinum salt containing 19.7 

 per cent of platinum. Upon neutralizing a sulphuric extract obtained 

 in refining with calcic hydrate and distilling with steam, Zalozieckift 

 obtained an oil containing nitrogen that formed a platosochloride 

 whose percentage composition corresponded with that of tetrahydro- 

 corridine (CloHigNCOaPtCIa, or to the formula (doHaiNCOoPtClg ; 

 another insoluble platoso compound was shown by analysis to have 

 the composition represented either by the formula (CioHi5NCl)2PtCl2 

 or (CioHi.NCO^PtCl^. 



Several hydrocarbons have been described as occurring in the less 

 volatile portions of American petroleum. Hemilian :i:| obtained from 

 the high boiling fractions "petrocene," a crystalline body melting 



* Ann. Cliim. Phys., [6.], II. 372. 



t Ber. der deutsch. chem. Gesellsch., 1883, p. 1873. 



t Journ. Soc. Chem. Ind., 1891, p. 120. 



§ Geological Survey of California, Appendix to Vol. XL., p. 89. 



II Chem. Centralb., 1890, p. 932. 

 1 Ber. der deutsch. chem. Gesellsch , 1887, p. 2097. 

 ** Monatsheft fur Chem., VIII. 224. 

 tt Ibid., XIII. 498. 

 Jt Ber. der deutsch. chem. Gesellsch., 1876, p. 1604. 



