B. Silliman on Petroleum from California, 343 
difference being apparently due to the greater or less degree of 
_ evaporation and oxydation of the products consequent on ex- 
_ posure to the warm air of a very dry climate. The specimens 
~ thus far examined from California are all from surface springs. 
_ When the oil is drawn from artesian borings the same change 
_ of density will undoubtedly be observed as in Pennsylvania. I 
- found the surface oil of Oil Creek, in 1855, having a density of 
_ $80 to 885, thick in warm weather as thin molasses, and in cold 
_ Weather quite viscid. The flow of wells in the same region is 
_ Dow quite thin, and has a density of -800 to ‘850. 
_ Appended are the results of Mr. Warren’s examination of the 
Same California oil now under consideration. 
_ “To Prof. Sturman, New Haven. 
“Dear Sir—The results of my examination of the erude California 
Petroleum which you sent me through Messrs. Spear, Burke & Co., of this 
tity, and which bore the seal of Messrs. Wyeth & Bro., are as follows: 
“Specific gravity at 17¢. 0°864—=33° Beaumé. 
1280 c.c. of the crude substance subjected to 
_ Wy process of fractional condensation, gave— 
_ 4lee. of light oil between 93° and 100°C. 
Se gi 100° and 140°C. 
— $25 “ Burning oil “ 140° and 310°C. sp. grit B. 
ae From this point the distillation was conducted in the ordinary 
Dol manne a common retort, no thermometer being used. 
Paro. lubricating oil of sp. gr. 294° Beaumé. 
293 & “ & “« 9g? és 
Specific grav- 
ity not taken.’ 
N72 ¢.¢, = 93-8 per cent of total product. 
ai What I have called light oil is not very volatile, and would not, I 
— ink, rank in the market as naphtha, at least not that taken between 
1» and 140°C. and it-is my opinion that the burning oil would take 
the Whole of the light oil, and still bear the commercial fire test. In that 
A some of the lighter of the lubricating il probably might be run into 
_ tie burning oil, so that the yield of the latter would be over 50 per cent. 
‘Boston, March 31, 1865.” 
Fy 
The specific gravity of the mixture determined by me is 0°753=58° Beaumé.—S. 
