PHARMACEUTICAL NOTICES. 
185 
tained containing the full equivalent of carbonic acid, and of 
course proportionably soluble in acids. 
Fermentation in Syrups. 
The almost inevitable state of fermentation into which many 
of our syrups enter, during the warmest season of the year, 
is but too well known, and often puts the pharmaceutist to 
considerable inconvenience. This more particularly relates 
to those syrups which contain much vegetable matter in solu- 
tion, independent of the sugar, which forms the basis of the 
preparations. 
Elias Durand some time ago communicated to me the 
fact, that Hoffman's anodyne, through the agency of the 
oil of wine which it contains, possessed the remarkable 
property of completely arresting fermentation in syrups, and 
preventing it before it has commenced. He finds that syrup 
of gum arabic, which is very liable to ferment and change, 
may be kept without difficulty, by the addition of 1.3 per 
cent, of Hoffman's anodyne, or about 1 part to 75 of syrup. 
Whatever part the oil of wine may act, in preventing fermen- 
tation, the same power is possessed by sulphuric and nitric 
ethers, and alcohol. A vegetable infusion containing about 10 
per cent, of solid matter in solution, was kept for many 
months, without apparently the slightest change, by the 
presence of a small quantity of sulphuric ether. 
A pectoral syrup, containing an unusually large amount of 
vegetable matter in solution, such as gum, extractive, etc., 
which was found to ferment even in moderately warm wea- 
ther, was wholly prevented from so doing, even during the 
warmest days of the past summer, by the addition of six per 
cent, of spirit of nitric ether. 
The superior advantage, however, of the Hoffman's ano- 
dyne, is due to the smallness of the proportion requisite, and 
to the slight volatility of the oil of wine, which consequently 
will continue its influence longer than the ethers. 
An additional evidence may be adduced in the case of 
brown mixture, which, when made without spirit of nitric 
Vol. vii, — No. nr. 24 
