MABERY. — CONSTITUENTS OP PETROLEUM. 133 



173° decane, a considerable quantity collected at 170°-171°, 80mm., 

 which distilled at 235° 240°, 717 mm. Its composition was shown 

 by analysis : — 



0.2008 gram of the oil gave 0.4121 gram CO., and 0.1641 gram HoO. 

 0.2540 gram of the oil gave 0.3532 gram AgCl. 



Found. 

 T. II. 



55.96 



9.08 



34.38 



This substance is, therefore, a dichlordecaue. The quantity of the 

 dichlordecane was barely sufficient for a determination of its specific 

 gravity; it gave at 20°, 1.0126. 



The presence of a decane at 174° seems therefore to be established 

 in Pennsylvania petroleum, confirming the observations of Warren, who 

 alone of all those who have examined American petroleum found a 

 body at this point. If Pelouze and Cahours had carried their course 

 of distillations sufficiently far, they could not have failed to discover 

 this body, since it forms such a large proportion of the higher boiling 

 petroleum distillate. Those chemists did, however, collect a distillate 

 at 180°-182° which gave analytical values and a vapor density very 

 closely supporting the formula C11H24. For some time I was in doubt 

 as to whether a distillate might not persist at this point, and it was 

 only after a prolonged series of separations that it was possible to 

 separate the distillates 180°-182° entirely into higher and lower limits, 

 thus supporting the conclusion of Warren, that Pennsylvania petro- 

 leum contains no hydrocarbon in appreciable quantity boiling in the 

 vicinity of 180°. 



Hendecane, C11H04, 196°. 



With increasing boiling points the distillates showed less stability, as 

 indicated by more color in the residue in a long course of distillations, 

 althounrh this was not sufficient to interfere with the collection of a 

 homogeneous body within narrow limits of temperature. Between 189° 

 and 192° distillates early began to accumulate, and the quantity gradually 

 increased until 150 c.c. was obtained which distilled entirely at 190°- 

 191° under 730 mm. 



On standing over sodium, a portion of this distillate deposited a red- 

 dish flocculent precipitate in very appreciable quantity, which indeed was 



