296 
EDITORIAL. 
Plumbum. — Iodide of Lead is introduced, and the nitrate is employed as 
its source, which is greatly preferable to the acetate, because the acetate of 
potassa resulting, when the latter is used, acts as a solvent for the iodide 
and causes waste. 
Potassa. — Pure Carbonate of Potassa is made by heating the bicarbonate 
to redness, lixiviating and evaporating to dryness. Citrate of Potassa at last 
is a recognized preparation, and is made from the bicarbonate of potassa 
and citric acid. By employing the latter salt, the silica of the carbonate is 
avoided. In the note to the formula for Liquor Potasses Citratis, or neutral 
mixture, it is stated that that preparation may be made from citrate of po- 
tassa and water, but it thus contains no carbonic acid, which is considered 
a desirable ingredient. This may be remedied by dissolving the citrate in 
carbonic acid water. Cyanuret of Potassium is now made by Liebig's formula, 
which yields it sufficiently pure for medical use and is a more manageable 
process. Iodide of Potassium is directed to be made by saturating a solution 
of potassa with iodine, evaporating to dryness, and heating the residue 
to redness, mixed with charcoal powder. The residue is lixiviated, and 
yields by evaporation a pure-white salt. 
Spiritus. — In Compound Spirit of Juniper, Spirit of Pimento, and Spirit of 
Rosemary, the volatile oils are merely dissolved in the alcohol without dis- 
tillation. 
Syrupus. — Syrup of Gum Arabic, we are glad to see, has found a place, after 
being omitted in the edition of 1840. The gum is directed unpowdered, to 
enable the apothecary to select it. Syrup of Citric Acid is a substitute for 
syrup of lemons, than which it is much less acid. Syrup of Garlic is now 
made without heat, and a specified quantity of the acetic liquor is directed. 
There are two formulae for Syrup of Rhatany: — In one the solution of extrac- 
tive matter is obtained by direct solution from the root ; in the other, the ex- 
tract is dissolved in water and filtered. As only the best root will yield two 
ounces of extract to the pound, it follows that the syrup made directly from 
the root is liable to vary in strength. It is better therefore to employ the ex- 
tract when it is of aqueous origin. The formulae for Syrups of Rhubarb, Ipecac, 
Seneka, Tola and Ginger, have been modified advantageously. Wild Cherry 
Syrup is new in the work. The first 500 copies of the Pharmacopoeia that were 
issued contained an error in the second formula for Compound Syrup of Sar- 
saparilla, the words two pints being used instead of ten pints. In the remain- 
der of the issue the leaf was reprinted correct. Those whose copies contain 
the error should correct it with the pen. 
Tinctura. — Tincture of Aconite Boot has been made weaker than Fle- 
ming's, being twelve ounces to two pints. It requires careful manipulation 
to exhaust the root with the small proportion of menstruum, and we have 
found digestion at 150° in a corked bottle to aid very much. Tincture of Pe- 
ruvian Bark is made from Yellow Bark. The Compound Tincture from Red 
bark. Tincture of Jalap is weaker in theory, but of the same strength in 
reality. If Tincture of Nux Vomica is made by displacement, the nux vomica 
should be in fine powder. The formula for Tinctura Saponis Cmphorata 
has been improved by the addition of water. 
