ON EXTRACT OF HENBANE. 
245 
ON EXTRACT OF HENBANE. 
By Mr. Charles Cracknell. 
(Prom the Transactions of the Pharmaceutical Society, London.) 
I have selected extract of henbane for my subject this evening, 
not only on account of its being one of the most useful and most 
powerful extracts prepared from any indigenous plant, but because 
it elucidates what I am about to state, and exhibits the differences 
I am about to describe in a more marked degree than any other 
extract, and consequently requires the greatest amount of care in 
the preparation of it. 
In order to render myself as clearly understood as possible, I 
shall speak separately of the three most important circumstances 
to be attended to in the making of the extract. 
Firstly. — The selection of the herb. 
Secondly. — The expression and evaporation of the juice. 
Thirdly. — The result. 
First then the selection of the herb — and this is manifestly a 
very important, division of my subject, for a good product is not 
likely to be obtained from a bad or unfit material — yet, notwith- 
standing its importance, it is the very thing least attended to. Our 
Pharmacopoeia (I hope soon to have the pleasure of saying our 
late Pharmacopoeia) gives a license for gathering the plant which 
I cannot but think quite unjustifiable, and which defies at least all 
uniformity of result, and most writers on the subject confine them- 
selves to the manufacture of the extract. For reasons to be pre- 
sently stated, I believe that henbane is only in a fit state for ex- 
tract during a very short period, that is to say, when the flowers 
at the summits of the plants and its branches are blown, but before 
they show any symptom of fading. Tf the plants have been care- 
fully gathered and sent to London, and have not grown amongst 
high weeds, the leaves will then be green to the bottom of the 
central stem, the seed vessels and seeds which are formed will be 
soft and juicy, and the weight of the plant will reside in the leaves 
and stems : if it be allowed to stasd a little longer the lower 
leaves become more or less yellow — the seed vessels, particularly 
the lower ones, become hard and prickly — the seeds assume a 
brownish color, and on holding the plant by the lower part of the 
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