EMPLASTRUM BELLADONNA. 
G85 
ascertained that they could not get the price of the opium such as they sold 
some years ago, and that now, to meet the price, there was one part of original 
opium mixed with three parts of something else. 
Mr. Williams stated that Persian opium used to be introduced in the form 
of sticks. He examined a few pounds some time ago, and found it contained 
12 per cent, of morphia. It was a beautiful opium, but still quite unsaleable 
for ordinary purposes. Reverting to the subject of hydrate of chloral, he re¬ 
marked that, notwithstanding what the Vice-President had said against the 
syrup, there was no doubt it would come into general use, aud become au article 
of commerce. It might be important to know how to test it, and see whether 
it contained 10 grains to a drachm or not. He had made syrup with glycerine 
and with sugar, and he preferred the glycerine to the sugar. If a small quan¬ 
tity, say half an ounce, of syrup be diluted with water, and mixed with a small 
quantity of ammonia, shaken up, warmed in a flask, then poured into a gra¬ 
duated tube, and allowed to stand, chloroform would be produced, which would 
separate in a distinct stratum, aud they could read off the amount of this which 
the syrup yielded. 
The following communications were read, but the lateness of the hour 
allowed of no opportunity for discussing them. 
EMPLASTRUM BELLADONNA. 
BY T. \V. GISSING. 
A few months since some questions appeared from me in the ‘ Pharmaceu¬ 
tical Journal’ respecting the preparation of emp. belladonnse. I preferred 
putting those questions to giving my own experience, hoping that some of 
my brother pharmaceutists would give theirs. In this I have been disap¬ 
pointed. My attention has been again called to the subject by the remarks of 
Prof. Redwood at the last pharmaceutical meeting. 
I think any one who reads the formula for emp. belladonna in the British 
Pharmacopoeia must at once see that the product must always be varying and 
uncertain. I will not digress to discuss the general question of aqueous ex- 
tracts, but it certainly wants thorough investigation. Suffice it that the Phar¬ 
macopoeia orders three ounces of aqueous extract of belladonna to be treated 
with six ounces of rectified spirit, and the resulting alcoholic extract to be mixed 
with three ounces of resin plaster. 
My experience of this is, that almost all samples of aqueous extract differ in 
the amount of alcoholic extract they yield; consequently, the plaister can never 
be of the same strength. Again, a fresh-made aqueous extract will yield more 
to alcohol than one that has been made twelve months. It would have been 
far better if the compilers of the Pharmacopoeia had ordered a given quantity 
of alcoholic extract to each pound of plaister, we should then have had something 
like uniformity of strength. As it is, I question whether any of the wholesale 
houses strictly follow the Pharmacopoeia formula in making their plaister ; or 
if they do, the varying yield from the aqueous extract may be the cause of their 
various prices for what is professedly the same preparation. 
The complaints about the present plaister running from under the edge of 
the leather arise, I think, from an injudicious spreading (too much plaister 
being put on), and from an insufficient margin. Careful selection of a stout , 
soft leather will, I think, remove the objection of the plaister penetrating 
through it. Certainly in all ways (except strength) the present plaister, in 
use, is an improvement upon the old. 
Wakefield , April 4 th, 1870. 
