IODIDE Oh" POTASSIUM. 
109 
fusion, as in experiments ten and eleven, should communicate 
to it a gelatinous consistence. When exposed for evaporation 
it lost its consistence and became perfectly fluid. 
1 
ART. XIX.-REMARKS ON THE METHODS OF PREPARING 
IODIDE OF POTASSIUM. By Benjamin F. H(eckley. 
An Inaugural Essay, J 
Of all the preparations of iodine, none has attracted more 
attention or been more extensively employed than the iodide 
of potassium. This arises, no doubt, from the numerous 
advantages w^hich this preparation possesses over many of the 
other iodides. The principal of these advantages are the 
following: — It is not decomposed by exposure to the atmos- 
phere; it is very soluble in water, and but slightly, if at all, 
deliquescent ; its elements are not separated by heat, and it 
may readily be obtained in a state of purity. It is also the 
iodide generally used for procuring others which are in- 
soluble. 
The increasing demand for this article has induced me to 
examine into some of the processes which have been devised 
for procuring it in a state of purity. 
This iodide is officinal in the United States and Dublin 
Pharmacopoeias. The name given to it by the former, is 
Potassii lodidum, and by the latter, Potassae Hydriodas. The 
first is the more correct, since it is (at least when not in solu- 
tion) an iodide, and not a hydriodate. 
The process of the United States Pharmacopoeia for pre- 
paring this iodide, is the same, in principle, as that recom- 
mended by Turner in 1825, and is as follows : 
