1695.] The Action of Heat upon EtJiylette. 397 



Table III. Temperature, 900 C. Rate of Flow, 40 c.c. 



Calculating the percentage for the change in volume, we obtain the 

 following figures : 



The original gas contained 96' 7 per cent, of ethylene, so that the 

 percentages of unsaturated hydrocarbons decomposed are 



On collecting these results in one table 



