282 
ORIGINAL COMMUNICATIONS. 
extremely moist; this, as before announced, is a fraud, done 
with the intention of increasing the weight of the substance. 
From this circumstance, and being less pure in other respects, 
the chemical action is not so intense when mixed with the 
iron. 
This article is now supplanted in commerce by one of 
purer quality from a celebrated French house, in whose hands 
it is a monopoly. This French iodine is presented in the 
form of beautiful laminae, having a strong metallic lustre, and 
so dry as not to be coherent, or to color the bottles in which it 
is contained. It evaporates by heat, without leaving any 
residue. 
As this combination decomposes very soon by contact with 
the air and action of light, it should be kept in dark bottles, 
filled up to the stopper, and enclosing several coils of iron wire 
of the height of the bottle; these serve a better purpose than 
the filings for combining with the disengaged iodine, as in the 
latter form its action is intercepted by a coating of oxide of 
iron falling upon it as it lays at the bottom. Vials of this 
preparation, sent from the store when prescribed, are some- 
limes brought back again, in consequence of its unexpected 
change in appearance. In this case, filtration through paper 
will, in a few minutes, restore it from an apparent muddiness to 
perfect limpidity. 
Murcurial Ointment* 
Much has been written upon this subject, and the labors of 
experimenters have all been directed to the same object, viz., 
the attainment of a method for preparing an ointment with 
mercury of perfect homogeneousness, in as short space of 
time as possible, and with an eye to economy of labor. A 
variety of substances have been recommended for the more 
complete extinction of the mercury, but with the exception of 
two, they are all liable to objections; these are suet and rancid 
grease, which have, in a measure, fulfilled the promised results. 
A better substitute has been recently found in spermaceti, by 
Mr. Lalaude, of France, who, from the employment annually 
