IODIDE OF QUTXIUM, ETC. 
305 
not always, a slight yellow tint was produced in the liquid. On 
cooling beautiful stellated groups of crystals were formed, bearing 
a resemblance to the disulphate of quinia. Occasionally but few 
crystals were formed, but in place of them an amorphous resin-like 
substance adhered to the sides of the vessel. It was considered 
preferable to obtain the iodide in the latter form, as it could be 
made into pills without an excipient. The pills after being made 
a short time become firm and hard. 
In reflecting on Dr. Tully's formula, it occurred to me that a 
sub-iodide of quinium, or perhaps an oxy-iodide, was formed while 
an equivalent of iodide of potassium was in excess, as the mother- 
liquid contains much of the latter salt as indicated by corrosive 
sublimate. It then appeared to me that in order to form the prot- 
iodide the neutral sulphate of quinia should be used. I then added 
half an equivalent of sulphuric acid to one equivalent of disulphate 
of quinia in sufficient water, and afterwards one equivalent of 
iodide of potassium, when a transparent yellow liquid resulted, 
which on standing a short time assumed a gelatinous consistence. 
By pressure the greater part of the liquid was separated, leaving 
a light yellow mass that was easily pulverizable when dry, but 
not crystallized. The expressed liquid again became gelatinous 
from the separation of more of the salt. 
I afterwards formed a double iodide of quinium and potassium, 
by adding to the solution of neutral sulphate of quinia as much 
iodide of potassium as was equal to two equivalents ; a yellow pre- 
cipitate occurred, which became crystalline on standing, and as- 
sumed the form of small feathery prismatic crystals. This salt 
probably contains water of crystallization, as the product obtained 
is greater than on theory it should be, if anhydrous. 
By similar and parallel processes, protiodide of cinchonium 
and double iodide of cinchonium and potassium were made. I 
formed what I suppose are the deutiodides of cinchonium and qui- 
nium, by precipitating the potassium from the double iodide of 
these bases and potassium, by means of an alcoholic solution of 
tartaric acid, in the form of bitartrate of potassa. The solution 
after being filtered was evaporated spontaneously. The salt of 
quinia is in the form of a deep brown amorphous mass : that of 
cinchonia in fan-shaped clusters of crystals. 
A solution of iodide of cinchonium and potassium in alcohol, is 
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