590 
Proceedings of ike Royal Society 
After saturation, the fluid was almost colourless, having only a 
pink tinge of iodine. The two above fluids can (after washing 
with dilute KOH and drying) with some difficulty be fractionated. 
C 2 H 4 C1 2 boils at 85° (Fittig). 
C 2 H 4 C1I „ 147° (Maxwell Simpson). 
Preparation of Acetylene (C 2 H 2 ) from Ethylene Dibromide 
(C 2 H 4 Br 2 ). 
Having prepared about a kilo, of C 2 H 4 Br 2 , 1 decomposed it accord- 
ing to the method described by Sabanjeff (Annalen, Band 178). 
Briefly described, this method is as follows : — Into a thick flask of 
about one litre capacity, more than half filled with a concentrated 
alcoholic solution of KOH, and heated over a water-bath to 100° or 
thereabouts, C 2 H 4 Br 2 , pure or diluted with alcohol, is slowly and 
regularly dropped from a separating funnel. The C 2 H 2 disengaged, 
passes off through an upright Liebig’s condenser, also affixed to the 
flask, by which means most of the monobrom-ethylene (C 2 H 3 Br) 
formed at first, and carried away along with the C 2 H 2 , is returned to 
the flask. Some of it, however, escapes undecomposed from this flask 
into a second one, also containing alcoholic KOH, and fitted with 
