Miscellanies. 377 
yessel I used was a rather large and tall flask, having a narrow orifice. 
In one trial I used twenty five grains of iodine, and half an ounce 
measure of fuming nitric acid; and in another, I employed twice 
these quantities of the materials. After introducing the iodine and 
acid into the flask, the liquid was made to boil. As soon as any 
iodine sublimed and condensed on the sides of the vessel, it was 
washed back again into the liquid by agitation. After the process 
had been continued some time, a precipitation of white crystalline 
grains was observed to take place; and the operation of boiling and 
washing back the sublimed iodine was continued until the free iodine 
had to a great extent disappeared. The whole was then decanted 
into a shallow basin, and evaporated to dryness. Any free iodine 
which had remained was soon dissipated by the heat. The residue 
of the evaporation consisted of whitish crystalline grains, which were 
iodic acid, retaining a little nitric acid, from which they appeared to 
be freed by one or two solutions in water, and re-evaporations, when 
they lost much of their crystalline appearance, and became a whitish 
deliquescent mass, occasionally with a slight purplish tint, from a ten- 
dency to decomposition by the heat of evaporation. 
The general properties of the matter thus obtained, sufficiently 
identified it with iodic acid. Exposed to a sufficient heat, it was 
decomposed, and iodine sublimed. Its solution in water gave a pre- 
cipitate with nitrate of silver, soluble in ammonia. Saturated with 
potash, it gave by evaporation a salt composed of grouped cubical 
crystals, and deflagrating on hot charcoal. 
The quantity of the acid obtained by this process, of course, must 
vary, according to the care taken to prevent the dissipation and loss 
of iodine. Where no particular precautions were taken to prevent 
its loss in the state of vapor, and where the process was not col 
tinued until the entire disappearance of iodine, the quantity of acid 
obtained approached that of the iodine employed. In operating with 
the relative proportions of iodine and acid which I have mentioned, 
Ihave no doubt that 2 farther addition of iodine might be made to 
the liquid, after the acidification of what had been at first introduced ; 
and the process might then be farther continued, asbefore- = 
I find, conformably to the observation of M. Serullas, that iodic 
acid does not attack gold. Its solution seems to have no action on 
that metal even when aided by heat. It is equally inert in regard to 
platinum. Zine is at first attacked by it with effervescence, especial- 
ly when diluted ; but the action ceases almost immediately, appa- 
Vor. XXI.—No. 2. 48 
