ON IMPORTATIONS OF IODINE. 
195 
case presented of an adulterated article of iodine, though it is 
said to be frequently adulterated with black oxide of man- 
ganese, plumbago, coal, slate, sand, &c, and M. Herberger 
found in one sample, native sulphuret of antimony, and in 
another more than half the article composed of artificial 
graphite ! * Dr. Christison, however, never met with any 
of these adulterations in his observations, and Dr. Pereira 
says, " in no samples of iodine which I have examined have 
I ever found any of these substances. 1 ? (Mat. Med., i. 225.) 
As iodine is obtained from an aqueous solution, as it is 
moreover volatile, (for though its point of volatilization is 
347°, its vapor passes over to a considerable extent with 
that of water at 212°,)t it might naturally be inferred that it 
would be found very difficult, — without considerable loss. — 
to separate the iodine from this moisture. 
Accordingly, this article, as met with in commerce, almost 
always contains a greater or less proportion of water, — the 
quantity of which is appreciable with tolerable precision 
by simple inspection, and unless considerable, in no wise 
affects its usefulness, as its chemical and medical properties 
remain unchanged ; the only disadvantage being that the 
variableness of its amount of moisture interferes with uni- 
formity in the strength of its medicinal preparations. Where 
the degree of dampness is well ascertained it obviously 
could not diminish the therapeutic value of its solutions, 
the principal form indeed in which it is administered. 
Within a few years past, a process has been success- 
fully applied of resubliming this substance, and obtaining 
it nearly or quite anhydrous ; thus presenting the pharma- 
ceutist (at an advanced price of course) with a pure article. 
I am informed by one of the leading chemical manufac- 
turers of our city, that it has been but a very few years 
since this improvement in the manufacture, or rather in the 
* Am. Jour. Pharm., vol. xviii., 77. 
t Iodine evaporates at ordinary temperatures, and much more 
rapidly when damp, than when dry. 
