188 
ON THE TARTRATE OF IRON AND POTASSA. 
ounce. It is intended by some physicians as a substitute for 
the weaker solution of morphia, in being more palatable : be- 
sides the solution very soon decomposes, and becomes cover- 
ed with a mucilaginous film, which can only be avoided by 
adding a few drops of alcohol; this however, is objected to, 
on account of the taste. 
ART. XXX1II.-ON THE TARTRATE OF IRON AND POTASSA. 
By William Procter, Jr. 
This preparation has been much neglected, doubtless on 
account of the difficulty of obtaining it of a good quality. 
Many processes and formulas have been published for its 
manufacture, but hitherto, none without objections. Accord- 
ing to the Edinburgh and Dublin Pharmacopoeias, metallic 
iron is mixed with bi-tartrate of potassa and water, and the 
mixture exposed to the air for several weeks, during which 
the iron becomes peroxidized, and united with the excess of 
acid in the bi-tartrate. By solution and evaporation a double 
tartrate of iron and potassa results. If no other objection 
could be urged against this process, the length of time requir- 
ed renders it ineligible. 
Our Pharmacopoeia of 1830, directs precipitated carbonate 
of iron to be boiled with bi-tartrate of potassa, and the solu- 
tion which contains the double tartrate is evaporated to dry- 
ness. In this process the objection is that the sesquioxide of 
iron is not presented in a state favorable to ready combina- 
tion, and but a small product is obtained. 
The late London Pharmacopoeia, (1836,) contains a process 
of which the following is a sketch. Sesquioxide of iron, (the 
precipitated carbonate of our Pharmacopoeia,) is dissolved in 
hydrochloric acid ; the solution thus formed mixed with a 
large quantity of water. The sesquioxide of iron is then 
