302 
PHARMACEUTICAL MEETING. 
cipitation with sulphide of ammonium was employed to determine the amount 
of bismuth present; this gave, on washing and drying, 0-327 grammes of BiS 3 in 
the fluid half-ounce, which represents 1-114 grains of the teroxide as being pre¬ 
sent in the drachm. Now, although the circular which accompanies the Liq. 
Bismuthi states that 5j is equivalent to a full dose (fifteen to twenty grains) 
of the insoluble trisnitrate, I do not think such can be the case. The idea evi¬ 
dently is that the metal, when in the soluble form, is much more active than the 
ordinary insoluble modification, and there can be no doubt that it is so to a cer¬ 
tain extent; but I should consider three grains to the drachm as the minimum 
dose : even more than this quantity may be easily introduced into such a solution 
as the above. The following is probably the mode pursued in making this solution : 
—430 grains of metallic bismuth are dissolved in a sufficient quantity of nitric 
acid, and this solution of ternitrate of bismuth is then precipitated with ammonia, 
and the resulting hydrated oxide well washed; 480 grains of citric acid are then 
exactly neutralized with ammonia, and the moist oxide is gradually added to the 
boiling solution of citrate of ammonia. The oxide is slowly but perfectly 
taken up. Ammonia is slightly evolved during the boiling, (probably from the 
decomposition of the citrate of ammonia per se,) but the solution becomes 
slightly acid, and remains so until the completion of the process. The solution 
is then neutralized with ammonia, and the whole is made to measure one pint. 
This solution will contain three grains of Bi 0 3 to the 5j. It is more elegantly 
made by dissolving the citrate of bismuth in citrate of ammonia.* 
Tartaric acid has also a similar action upon bismuth. 
There seems to be a limit to the solubility of chemically pure citrate of bis¬ 
muth ; but the solubility is wonderfully increased by the presence of mineral 
acids. This is, no doubt, due to the greater solubility of the salts formed by the 
latter acids in citrate of ammonia. 
The reactions of this bismuthic solution are as follows :— 
Ammonia and carbonate of ammonia give no precipitate. Potash and soda, or 
the carbonates of these alkalies, give precipitates insoluble in an excess of the 
precipitant. Nitric, sulphuric, and hydrochloric acids give precipitates soluble 
in an excess of the respective acids, and reprecipitable on neutralization w T ith 
ammonia. These precipitates are also soluble on the further addition of ammonia. 
Water gives no precipitate. Sulphide of ammonium throws down the whole of 
the bismuth as sulphide. 
As the reactions of citric and tartaric acids are at present little known, it is 
my intention to investigate the matter further, particularly with a view to its 
analytical bearing ; but in the meantime, I place before you the results of my in¬ 
vestigation of the Liq. Bismuthi. 
Mr. Schacht (of Clifton) said that although the author of the paper had not 
thought fit to mention his name in connection with the liquor bismuthi examined, 
there could be no doubt, from the quotation made from the circular, that the 
preparation the meeting had just heard so freely discussed was that made by him¬ 
self. Assuming this to be the case, he could state that the author had well per¬ 
formed his task in submitting it to analysis. The preparation, sold as liquor 
bismuthi (Schacht), consisted of bismuth oxide, citric acid, and ammonia, and 
the quantity of oxide of bismuth present was one grain in each fluid drachm. 
This, however, had been published in the ‘ Lancet’ several months ago. A fact 
so easy of investigation he had never attempted to keep secret, but, on the con¬ 
trary, he had told its composition to every medical man with whom he had con¬ 
versed on the subject. He had adopted the name “ Liquor Bismuthi (Schacht),” 
* Citrate of bismuth is a very insoluble salt, got by the double decomposition of citrate 
of potash or soda, and ternitrate of bismuth. The citrate, as made in this manner, is ex¬ 
tremely soluble in ammonia, or a solut ion of citrate of amiponia. 
