593 
of Edinburgh , Session 1877 - 78 . 
combine very slowly, tbe iodine must be distributed in numerous 
small flasks, which ought to be hung on a glass rod, horizontally 
placed, to admit of their being shaken from time to time. (See 
Sabanjeff, Annalen, Band 178 ; also Semenoff (for C 2 H 4 I 2 ), 
Zeitschrift fiir Chemie, 1864.) 
Sabanjeff states that he, while preparing the iodide in this 
manner, got at the same time a large quantity of a liquid 
iodide (also of the formula C 2 H 2 I 2 ). He supposes the one to 
CHI CH 2 . 
be 1 1 and the other 1 1 Curiously enough, I only obtained a 
CHI CI 2 . 
few drops of a liquid which could at all correspond to this second 
iodide. Whether it was the iodide, or a product of the action of 
the iodine in the alcohol, &c., I cannot say. The quantity got was 
too small. 
The chief object which I had in view in preparing the preceding 
acetylene compounds (chlor-iodide, iodide, also tetrabromide, &c.), 
was that from them I might be able to obtain the corresponding 
cyanogen ones, which, if got and treated with an alkali, would 
probably have yielded chloro- (or iodo-) acrylic, and fumaric or 
maleic acids. I have not, however, as yet succeeded in obtaining 
them. 
Whether C 2 H 2 combines with iodide of cyanogen when the latter 
is dissolved in alcohol, I cannot yet say. It does not with dry 
ICK 
All attempts to obtain the cyanogen compounds of C 2 H 2 by 
heating in sealed tubes (at temperatures ranging from 120° to 0°25) 
chlor-iodide or iodide of acetylene with the various cyanides {KCN, 
AgCN, (AgCH + KChT), H 2 (CN 2 ),} or with ICN and a metal, were 
fruitless. 
When H 2 (CN) 2 was used, generally no reaction occurred, and in 
nearly all the other cases ammonium salts were formed in large 
quantity. I had unfortunately only a small quantity of the chlor- 
iodide at my disposal. 
Acetylene does not seem to be absorbed if passed into a hot 
solution of “ nascent” formic acid, i.e. } a solution containing KCN 
and KOH. 
