MABERY AND QUAYLE. — CANADIAN PETROLEUM. 109 



gents, as has been more fully described in another paper. A distillate 

 194°— 196° from Pennsylvania petroleum gave 0.02 per ceut bromine ab- 

 sorbed ; another 209°-210° 0.09 per cent ; a distillate 209°-210° Ohio puri- 

 fied in the same manner gave 0.03 per cent bromine, and a Canadian 

 distillate, 0.12 per cent. These results may be accepted as showing no 

 absorption of bromine, since this method is not capable of indicating such 

 small percentages. That the quantity of sulphur remaining in the crude 

 oil after treating with fuming sulphuric acid was too small to affect the 

 amount of bromine absorbed is shown by the low percentage of sulphur, 

 0.09, and in the distillate 200-230 atmospheric pressure, 0.001 per cent. 



When the complex composition of American petroleum is borne in 

 mind, and the probability of substitution in the less volatile portions, the 

 difficulties in testing for unsaturated hydrocarbons are evident. Conse- 

 quently all discussion of this subject by those best informed has been 

 undertaken with reservation, while those of others partake more of the 

 nature of speculation on results which the authors were content merely 

 with presenting, without attempting explanations which the facts were 

 insufficient to justify. 



We have had good evidence that unsaturated hydrocarbons are con- 

 tained in distillates prepared from crude petroleum. Polymerization 

 on standing, the formation of dark colored heavy oils, can only be 

 explained by changes in unsaturated hydrocarbons or unsaturated sul- 

 phides. Heptylene was described in another paper as a constituent of 

 Ohio oil. 



Since the products described in this paper were contained in the oil 

 extracted with sulphuric acid from burning oil distillate, we have assured 

 ourselves by experiments already described that ordinary concentrated 

 sulphuric acid such as is used in refining burning oil distillates, removes 

 without decomposition, from such distillates, the unsaturated hydrocar- 

 bons as well as the sulphur compounds; and consequently that the sludge 

 oil after carefully separating from the acid contained constituents of the 

 crude oil and not products of decomposition. 



In fractioning in vacuo as previously explained, a considerable propor- 

 tion of the distillates from the sludge oil collected below 100°, which 

 could be distilled without decomposition under atmospheric pressure. 

 These portions were therefore carried through .ten distillations under at- 

 mospheric pressure, and the portions distilling below 150° in vacuo also 

 through ten additional separations in vacuo. On account of great pres- 

 sure of other work, these distillates stood three years before their study 

 was resumed, although when first obtained they received sufficient atten- 



