252 Peckham — Nitrogen Content of California Bitumen. 



from infiltration of rain-water and accompanying oxj^gen, by 

 overlying formations. 



The manner in which this nitrogen is combined was not then 

 made a subject of research. It was however my conviction at 

 that time, based largely upon observations made upon the spot, 

 and judged in connection with these results of analysis, that 

 the nitrogen must in some manner be held in combination by 

 bonds that are easily broken, and that in the re-arrangement 

 that followed, the nitrogen content either became free, or 

 entered more stable forms of combination, after the manner 

 in which the process of fermentation converts complex nitro- 

 genous compounds into simpler forms. Here this matter rested 

 for many years. 



In April, 1892, in the laboratory of the University of Michi- 

 gan I distilled some of the same samples of Wheeler's Canon 

 petroleum in which I had determined the nitrogen more than 

 twenty years before. The distillation was conducted at a tem- 

 perature approaching the red heat and furnished products of 

 destructive distillation. While observing the effects of various 

 reagents upon the distillates, which I was handling in very 

 small quantities, I noticed the very peculiar and persistent odor 

 of pyriclin. The appearance of this substance under the condi- 

 tions present did not surprise me. I considered it to be a 

 product of the destructive distillation of the petroleum at a 

 temperature approaching the red heat.* 



After I returned to California last October and made the 

 acquaintance of Dr. Frederick Salathe, he one day showed me 

 a small vial containing a black oil, that was in appearance Dip- 

 pel's oil. He said that he had obtained the oil by washing a 

 distillate of California petroleum with dilute sulphuric acid, 

 and further that all of the crude oils found in the neighbor- 

 hood of Santa Paula yielded basic oils to dilute sulphuric acid. 

 Dr. Salathe seemed to be impressed with the importance of his 

 discovery as demonstrating beyond any question the animal 

 origin of the bitumens ; a proposition to which I gave instant 

 assent. 



The importance of this discovery immediately impressed me 

 from the technological side, and I urged the doctor to ascer- 

 tain what results would follow the removal of the basic oils 

 from the various commercial products found in the refinery. 



In the laboratory I soon treated both crude oils and their 

 distillates, and found that the basic oils in their natural condi- 

 tion were combined with an exceedingly viscous feebly acid 

 tar. When the crude oils are treated with dilute acid, this acid 

 radical forms a hydrate which produces with the other constitu- 



*This Journal, vol. xlvii, p. 30, Jan. 1894. 



