MABERY. COMPOSITION OF PETROLEUM. 287 



35.78, calculated from the elements, assigning to the cyanogen group 

 the value 5.33, which was determined from ethyl cyanide, C 2 H 5 CN. 

 The theoretical molecular refraction for the nitril calculated on the 

 same basis is 36.45. 



The nitril was saponified by heating it to 110° with concentrated 

 hydrochloric acid. The acid formed had the odor of alphatoluic acid, 

 but the amount obtained was not sufficient for complete examination. 



When heptamethylene chloride was brought together with metallic 

 sodium, a vigorous action soon set in with the evolution of oreat heat, 

 sufficient to cause the decomposition of the products unless it was con- 

 trolled by cooling. This reaction was best carried on by dissolving the 

 chloride in ether, adding the sodium in slight excess over the calculated 

 amount, and keeping the solution cold. In two hours the reaction was 

 complete. The products included an unsaturated hydrocarbon, boiling 

 point 97°, and another hydrocarbon, boiling point approximately 220°- 

 230°. That the hydrocarbon boiling at 97° was unsaturated was shown 

 by the formation of a bromine addition product ; bromine added readily 

 in the cold with no escape of hydrobromic acid. A Carius determina- 

 tion of the bromine in this product gave the following result : — 



0.2045 grm. of the oil gave 0.3023 grm. AgBr. 



Calculated for C 7 H I2 Br,. Found. 



Br 62.5 62.9 



The specific gravity of the dibrom-derivative at 20° was 1.648. A 

 determination of its molecular weight was made : — 



0.9233 grm. of the oil and 25.3 grms. of benzol gave a depression of 



0°.725. 



Calculated for C 7 H 12 Br 2 . Found. 



256 247 



The odor of the unsaturated hydrocarbon was very sharp and pene- 

 trating, very different from that of the paraffine and methylene hydro- 

 carbons, but resembling the olefines. In further proof that it contained 

 doubly bonded carbon, it was titrated with the Hiibl reagent, an alcoholic 

 solution of iodine and mercuric chloride. The amount of iodine absorbed 

 was approximately equivalent to two atoms of iodine for each molecule 

 of the hydrocarbon. When heated with hydriodic acid, the monoiodide 

 was readily formed. The specific gravity of the unsaturated hydrocarbon 



