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SELECTED ARTICLES. 
all the other principles. Haase also supposes the resin to be 
the active ingredient. 
In the present state of our knowledge of this subject, it is 
not in our power to determine which of these views is the 
correct one; and hence, in the modes of conservation and ex- 
traction which we employ, it is prudent to have regard, if 
possible, to all of them, and not to rely upon any one of 
them in particular. Thus were we to admit of the state- 
ment of Dulong, that the active principle of foxglove is 
insoluble in either, we must conclude that the choice of ether as 
a menstruum is improper, that the tincture formed by it is 
powerless, and that the active principle is excluded. Yet the 
French Codex, of 1816, as well as that of 1835, directed the 
ethereal tincture of digitalis; so also the Pharmacopoeia 
Belgica, the Pharmacopoeia Hannoverana, the Pharmacopoeia 
Regni Poloniae, (1817,) the Pharmacopoeia Borussica, and the 
Pharmacopoeia Saxonica; it is also sanctioned in the Pharma- 
copoeia of Brugnatelli, in that of Cadet de Gassicourt, and of 
Van Mons. But if we rely on the affirmation of Brault and 
Poggiole, that the active principle is soluble in sulphuric ether 
the foregoing authorities have given adequate formulae. 
Again, if the active principle is insoluble in water, as asserted 
by Brault and Poggiole, though contradicted by Dulong, the 
decoction and infusion of digitalis of the American and Euro- 
pean Pharmacopoeias are worthless; and the tinctura digitalis 
aquosa aetherea, added by Niemann to the Dutch Pharmaco- 
poeia, and also introduced into the Pharm. Man. Anvers, 
1812, is doubly absurd, as it employs both water and ether. 
In place, therefore, of relying on this or that authority, 
when they differ so widely as to the principle on which the 
medicinal powers depend, the more prudent course will be to 
use such process of extraction only as will deprive the sub- 
ject of the greatest number of its principles, care being taken 
that none of them shall be excluded, unless such as are mani- 
festly inert. 
In the following observations, I shall confine myself to the 
