184 Mr. F. Guthrie on Iodide of Acetyle. 
upon considerably more than an equivalent of dry phosphorus in 
a dry, long-necked flask, and dry iodine added in small quan- 
tities at a time in rather more than equivalent weight. The flask 
is then warmed till action has ceased. The liquid contaiming 
uncombined iodine is poured into a retort contaming a piece of 
dry phosphorus, and placed in an inverted position in connexion 
with a condenser. After boiling for a few minutes, the retort 
is reverted and the contents distilled off. The boiling-point 
remains tolerably constant at 108° C.; the temperature may, 
however, be pushed to 120° C., at which point the residue in 
the retort is inconsiderable. The distillate is vigorously shaken 
with mercury until it becomes transparent, and then quickly 
decanted and rectified at 108° C. However cautiously the di- 
stillation be effected, a portion of the iodide appears to suffer 
decomposition ; hydriodic acid escapes, and a solid residue con- 
taining iodine is left in the retort. This is probably a substitu- 
tion product, containing iodine in place of hydrogen. 
In the above manner, by acting on 33 ozs. anhydrous acetic 
acid, with 9} ozs. iodine and about 1 oz. phosphorus, I obtained 
5 ozs. of iodide of acetyle. 
Iodide of acetyle is a transparent liquid of brown colour. This 
coloration is specific, and does not arise from dissolved iodine, 
for it cannot be removed by agitation with mercury. It boils at 
108° C. at 757 millims., and has the specific gravity 1:98 at 
17°C. Its vapour-density could not be determined with accu- 
racy, owing to the above-mentioned fact of its not being perfectly 
volatile without decomposition. It fumes strongly in the air, 
has a most suffocating odour, and an intensely acid and corro- 
sive taste. Water decomposes it instantly and with violence, 
hydriodic and acetic acids being formed. To this reaction is 
due the energetic action it has on organic bodies containing the 
elements of water. 
In the analysis of this body, the carbon and hydrogen were 
determined in the usual manner, moderately heated copper- 
turnings being employed in the anterior of the combustion-tube 
to arrest volatilized iodine. The iodine was estimated as iodide 
of silver. For this purpose a bulb containing a weighed quan- 
tity of liquid, and provided with two capillary tubes, was im- 
mersed in a solution of nitrate of silver. The point of the lower 
tube being then broken against the side of the vessel, and that 
of the upper with the fingers, the air was forced gradually 
through, and the bulb subsequently washed into the silver 
solution. 
Burnt with oxide of copper, °7827 grm. gave ‘4416 grm. car- 
bonic acid and ‘1641 grm. water. 
‘3038 grm. yielded ‘4140 grm. iodide of silver. 
