ON CHLORIDE" OF IRON AND SODIUM, ETC. 
137 
OBSERVATIONS ON CHLORIDE OF IRON AND SODIUM, AND 
OTHER DOUBLE SALTS OF IRON. 
By Frederic A. Cochran, of Baltimore, Maryland. 
Some time during February 1851, while preparing chloride of 
iron and ammonia, it appeared to me that chloride of iron and 
sodium might be a valuable salt of iron ; and not being aware that 
such a combination had been formed, I consulted the various works 
on Materia Medica and Pharmacy, but was unable to find any ac- 
count of it. Therefore, I prepared about half a pound by dissolv- 
ing the common carbonate of iron (peroxide) in hydrochloric 
acid, and adding to it a cold solution of crystallized carbonate of 
soda, so long as the peroxide of iron which it precipitated was 
readily re-dissolved. By this means I formed a very dark red 
nearly neutral solution of chloride of iron and sodium, almost taste- 
less, and only slightly astringent. This solution in a porcelain 
dish was placed on a boiling water bath to evaporate, and about 
the time for a pellicle to form, believing that the salt was 
amorphous, I was somewhat surprised to see all the solution 
converted into a magma possessing the common characteristics 
of hydrated peroxide of iron. It seemed to be decomposed, but 
as it was readily and entirely soluble in cold water, the evapora- 
tion was continued while its strong affinity for water caused it to 
dry slowly and in masses, which, however, whea dry, were easily 
reduced to powder, and not sensibly deliquescent in the air. This 
powder very nearly resembled peroxide of iron in appearance, 
was slightly saline and styptic to the taste, and in small quantity 
was entirely soluble in cold water, forming a solution of a clear 
claret color. About an ounce of this powder was loosely wrapped 
in a single piece of thin porous paper, and kept exposed in the 
air during " all the seasons and their change," and the paper is 
now only slightly stained yellow, and the powder, as if having 
absorbed a little moisture, is in dry pulverulent lumps. This 
powder is not quite so soluble as it was a year ago when it was 
made, and its solution does not now indicate the presence of iron 
with a solution of ferrocyanuret of potassium as it did slightly at 
that time. 
Reflection and experiment have induced me to believe that it 
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