ON CHLORIDE OF IRON AND SODIUM, ETC. 
139 
Dissolve the sesquioxide of iron in the hydrochloric acid in a 
porcelain dish without heat, and the bicarbonate of soda separately 
in the boiling water, and when the solution shall have cooled, add 
it gradually to the solution of iron, stirring after each addition, 
until the peroxide of iron which it precipitates shall cease to be 
readily re-dissolved. As this solution niters very slowly, it may 
be decanted after standing an hour. It should then be evaporated 
at a temperature not exceeding 150° F., and the residue reduced 
to powder and kept in glass stoppered bottles. If the bicarbonate 
of soda contain 40 per cent, of soda the quantity is only enough. 
Prepared in this manner ten grains of the dry powder dissolved 
entirely in an ounce of pure water, and formed a permanent pale 
red solution nearly tasteless, from which the salt was obtained 
unchanged by evaporation. But if twenty grains or a larger quan- 
tity be added to an ounce of water it forms a semi-solution, in 
which after a day or two, peroxide of iron sinks, leaving a clear 
nearly colorless supernatant solution of chloride of sodium. 
Boiling water produces the same change in a very short time. It 
is insoluble in alcohol and ether, and incompatible with the as- 
tringent vegetable tinctures, infusions and extracts, and the caustic 
alkalies. Considered anhydrous it consists of one equivalent of 
chloride of iron 63.42, and one equivalent of chloride of sodium 
58.72. Its equivalent is therefore 122.14. It contains 33 per 
cent. , of peroxide of iron.* 
*Gmelin's Handbook, (Vol. V, page 268,) under the head, " Carbonate 
of Ferric Oxide and Pota3h," says, "when a ferric salt is supersaturated 
with strong carbonate of potash, the precipitated ferric hydrate is redis- 
solved and forms a blood red solution. This solution is decomposed with 
precipitation of ferric hydrate, both by heat and by dilution with water or 
solution of caustic potash. Freshly precipitated ferric hydrate is not soluble 
in strong carbonate of potash, so that the presence of the potash salt formed 
at the same time [chloride of poatssium] appears to be necessary to the 
solution." A corresponding soda salt is noticed at page 272, carbonate of 
soda being used in lieu of the potash carbonate. 
In bringing forward these quotations, it is with a view of throwing some 
light on the composition of Mr. Cochran's salt of chlorine, sodium and 
iron, as he does not appear to have made an analysis, but assumes it to be 
an anhydrous chloride of iron and sodium from the ingredients employed 
to form it. The numbers used by Mr. Cochran as the equivalents for 
chloride of iron, indicate the proto-chloride, whilst he considers that the 
