and Observations on Iodine. 4,^1 
evaporating the clear liquor until it began to de|x)sit crystals. 
In this way I have procured substances which, when well 
washed in distilled water, afforded no iodine to nitric acid, 
which yielded chlorine and chlorionic acid when acted upon by 
luuriatic acid, and which when distilled afforded much oxy- 
gene and some iodine, and left substances which appeared to 
be mixtures of the earths with compounds that afforded iodine 
to sulphuric acid, producing a smell of sulphurous acid gas, 
and which probably consisted of the metals of the earths united 
to iodine. 
The triple compounds from lime and magnesia were soluble 
without affording iodine in sulphuric acid; but on evaporating 
the acid, at the time that the vessel of platinum in which the 
experiment was made became dry and almost red hot, the 
violet vapour was perceived. Even the triple compound from 
baryta did not afford iodine or oxygene by treatment with 
sulphuric acid, except under the same circumstances. 
3. When I first discovered that the triple compounds dis- 
solved in acids without effervescence, I thought it probable 
that the effect depended upon the formation of a compound 
of oxygene and iodine, similar to euchlorine, or the oxy- 
chloric acid, and which remained dissolved in the fluid ; and 
on this idea 1 made a number of experiments with the hope 
of obtaining such a combination in a detached form. 
I distilled the solution of the triple compound of potassium 
in sulphuric acid, but the only gaseous product I obtained was 
oxygene. Sulphuric acid and iodine condensed in the cool part 
of the apparatus, and the residuum was acid sulphate of 
potassa. 
Conceiving that a compound of oxygene and iodine might 
