HOW MUCH IRON DOES MISTURA FERRI AROMATICA CONTAIN P 429 
Cryst. ternitrate of bismuth . . 18£ oz. 
Citric acid.20 oz. 
Liq. ammoQ. fort.1 pint, or q. s. 
Distilled water. q. s. 
The citric acid is dissolved in two pints of the water, and the crystals of nitrate 
added. They rapidly dissolve, and after a little time a white precipitate begins 
to form. As soon as the nitrate has dissolved, the ammonia diluted with an 
equal bulk of water is added, little by little, until the precipitate is dissolved, 
and the liquid is neutral. The resulting solution is, if necessary, filtered, and 
diluted to the volume of one gallon. 
It will be observed that I employ rather more citric acid than the P. B. 
orders. This I find to be desirable when the crystals are employed in lieu of 
the nitric solution. 
The quantities for a pint are as follows:—Ternitrate of bismuth 995 grs.; 
citric acid 2^ oz.; liq. ammonise and water q. s. 
It might have been an advantage if Mr. Tichborne’s process had been given 
in the Pharmacopoeia instead of the present one, but this would have neces¬ 
sitated the introduction of the crystallized ternitrate as a distinct preparation, 
and the authors may have considered that confusion would arise if two nitrates 
of bismuth were officinal. 
HOW MUCH IRON DOES MISTURA FERRI AROMATICA 
CONTAIN P 
BY JOHN T. MILLER. 
I was lately asked the above question. In order to obtain some reliable 
information on the point, the following experiments were tried :— 
Powdered cinchona bark of good quality, fine iron wire (No. 36) free from 
oxide, calumba root, and cloves, in the quantities given in the formula, were 
macerated in 12 fluid ounces of peppermint water. The bottle stood in a 
warm room, and was often shaken. At the end of the third day the fluid was 
filtered off, and brought up to the specified measure by adding to it the washings 
of the residue. The inky-looking liquor was evaporated to dryness, the organic 
matter burnt off, the ash dissolved in strong hydrochloric acid, the ferric chloride 
reduced by zinc, and the iron then determined volumetrically by a solution of 
permanganate of potash. 
Several such experiments were made, in which different samples of cinchona 
bark were used. In another operation the iron wire was accurately weighed at 
the commencement, and -when the maceration was finished the metal was with¬ 
drawn from the mixture, well cleansed with boiling water, quickly dried, and 
then re-weighed. The loss was 3-2 grains. But scarcely 1 grain of this iron 
was found in the filtrate; the remainder had gone down in an insoluble state, 
and was left on the filter. A second trial with a different specimen of bark 
gave a similar result. 
In another experiment, fine, bright iron-filings were substituted for the wire. 
The product was the richest of all in iron, the weight found being 1-3 grains. 
Leaving out of account this last case, the conclusion arrived at was, that the 
Aromatic Mixture of Iron of the British Pharmacopoeia may contain from 0’7 
grain to 1 grain of iron in 16 fluid ounces. The quantity may occasionally 
exceed 1 grain, but will, I imagine, usually fall short of it. Much, no doubt, 
depends on the quality of the cinchona bark, the fineness of the wire, and on 
the temperature during maceration. A medicine like this, which contains in 
the usual dose only a small fraction of a grain of iron, can hardly be of much 
