of Heat and Pressure upon the Paraffins. 



193 



the probable presence of octylene, the boiling-point of which is given by 

 Bouis at 125°. and by Pelonze and Cahours at 118-120°, The reaction 

 with bromine yielded the following data : — 



Amount of hydrocarbon taken ........ 41 e grms. 



Amount of bromine needed 34*0 „ 



Equivalent of octylene 24*1 „ 



On the addition of bromine the hydrocarbon darkened rapidly in colour, 

 and a small quantity of tarry matter collected at the bottom of the flask. 

 As it was impossible to distil the mixture under the ordinary atmospheric 

 pressure, the bromide being decomposed by a very slight elevation of 

 temperature, it was treated with alcoholic potash, and distilled per ascvn- 

 sum for some hours until a few drops thrown into water floated upon its 

 surface. Water was then added, the lighted portion separated, dried, 

 and fractionated. The largest amount came over between 120° and 140°, 

 the next fraction from 140-160° being much smaller in quantity, whilst 

 scarcely any liquid distilled over between 160° and 180°. After this point 

 the thermometer became more stationary, and a fraction almost as large 

 as that at 120-140° came over between 180° and 200°. This, on renewed 

 distillation, boiled at 185-190° ; it had a feeble garlic smell, and was 

 heavier than water. Analysis showed that it had approximately the 

 composition C 8 H i5 Br. 



I. 0-4755 grm. bromide gave 0*4165 grm. silver bromide and -0180 grm. 

 reduced silver. 



II. 0*4600 grm. bromide gave 0*4100 grm. silver bromide and 

 0*0150 grm, reduced silver. 



Found. 



Calculated. , — K s 



I. II. 



Br 41-8 40-1 40-7 



According to Eubien*, by whom this compound was first described, its 

 boiling-point is 185°. 



The fraction boiling between 120° and 140° on repeated distillation was 

 separated into octane, boiling at 122-125°, and a liquid of an alliaceous 

 odour boiling constantly at 130-135°, which absorbed bromine with 

 avidity. This in all probability was caprylidene, the boiling-point of 

 Avhich has already been found by Eubien Qoc. cit.) to be 133-134° ; its 

 formation was doubtless due to the prolonged action of the alcoholic 

 potash on the C 8 H 15 Br. 



Action of chlorine on mixed hydrocarbons boiling at 122-125°. — 34 grms. 

 of the hydrocarbons were weighed out into a small distillation-flask, 

 immersed in a mixture of ice and salt, and a gentle stream of chlorine 

 sent through the liquid in the dark. The chlorine was rapidly absorbed, 

 and for the first hour but little hydrochloric acid was disengaged ; during 



* Ann. Ch. Phann.vol, cxiii. p. 294, 



