wr. Inglis’s Extracts from his Prize Essay on Iodine. 13 
of nitrogen is precipitated; so that if we suppose it to bea 
hydriodate, then we should not require to say that hydriodic 
acid and iodide of nitrogen were formed at the moment of so- 
lution, but that they existed in the compound ready formed, 
and that in consequence of the greater affinity which hydriodic 
acid has for water than for the iodide, they separate, and the 
iodide precipitates, whilst the acid is held in solution, as I found 
to be frequently the case when experimenting on the double 
iodides to be noticed hereafter. 
If, instead of using the iodine alone with the aqua ammonia, 
there be added equal parts of a strong tincture of iodine and 
the ammonia, then I found that instead of the dark detonating 
ioduret, there was formed an iodide of carbon, similar to that 
formed by the tincture of iodine, and the alcoholic solution of 
potash. ‘The periodide of carbon by this process is obtained 
in pretty large plates. 1 equivalent of ammonia +1 of alco- 
hol + 6 of iodine are required, and there result 1 atom of 
nitrogen gas (which is evolved and found in the upper por- 
tion of the vessel), 1 atom of water, 2 of iodide of carbon, and 
3 of hydriodic acid, which latter unites with the excess of am- 
monia remaining in the solution. Its presence is indicated by 
the addition of bichloride of mercury, and a little muriatic acid 
to saturate any excess of ammonia which might redissolve the 
red periodide of mercury which is precipitated. 
The black detonating teriodide of nitrogen is decomposed 
by almost every substance: oils and fatty matter do not cause 
its detonation as they do that of the chloride of nitrogen. The 
strong mineral acids all explode it when in a perfectly dry 
state. 
I allowed aqua ammoniz to remain over the iodide of nitro- 
gen, in which there was no trace of free iodine, for several 
weeks; the iodide was decomposed, almost half of the vessel 
in which I had it was filled with nitrogen, and small crystal- 
line points were seen floating in the fluid, at the same time that 
a yellowish deposition was seen at the bottom. Alcohol when 
allowed to remain in contact with the iodide, decomposes it. 
Nitrogen is evolved, the liquid becomes of a deep red colour, 
and iodide of carbon is formed, the smell of which is per- 
ceived in the fluid. Pure water is even reacted on by, or re- 
acts with, the elements of this iodide. I found azote given off 
as before, the water assumed a ruby tint, and small crystals of 
iodine were precipitated. 
The most probable cause of the explosive power of the 
iodide of nitrogen is this: Nitrogen requires an immense 
power to liquefy it. Indeed, by condensation it has never yet 
been done; but chlorine and iodine possess this power; the 
