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SELECTED ARTICLES. 
conclure qir il est des teintures que ne jouissent pas tonjours des 
proprietes primitives des substances dont elles sont composees. 
Ce fait est d'autant plus a considerer, que depuis que dessic- 
cation des plantes a ete en grande partie confieades personnes 
etrangers a la pharmacie, ces substances sont liverees au com- 
merce dans un etat de deterioration veritablement penible a 
constater."* 
If two tinctures be made, one with proof and the other with 
rectified spirit, on equal quantities of the same coarse powder 
of foxglove, the former will, after equal digestion, be brown, 
and the latter a brillant green; the taste of both will be ex- 
ceedingly bitter. If the residue of both be filtered off, and 
an equal quantity of rectified spirit be digested on each, the 
residuum of that on which proof spirit had been previously 
digested will afford a brilliant green tincture, and the other a 
tincture of pale hue. Thus the green matter of the leaf is but 
little soluble in proof spirit, although largely soluble in recti- 
fied spirit. We do not know whether this is merely chro- 
mulite, or whether it is this substance, combined with the 
active principles, if there be more than one; and hence, in this 
state of uncertainty, it is prudent to retain the green matter. 
The resin, which is supposed by some to be the medicinal 
agent, the essential oil, the fixed oil, the fatty substance, and 
the bitter principle, are all soluble in rectified spirit; but we 
are not so certain that they are equally soluble in proof. 
This point settled, the plan which I propose is easily exe- 
cuted; it requires no skill, and can scarcely fail, if common 
care be taken. It consists in plucking the proper leaves off 
the living plant on the spot where it grows, instantly throw- 
ing them into the strongest alcohol, digesting for six weeks, 
pressing out the tincture, and filtering it. Here all the 
sources of deterioration are obviated, and we preserve the 
virtues of the recent plant unimpaired. 
The ratio of the recent plant to the rectified spirit may be 
so contrived that the resulting tincture shall correspond with 
♦Bulletin des travaux de la Sociele de Pharmacie de Paris Octobre, 1830. 
