10S 
ON ALCOHOLIC TINCTURES. 
11. Belladonna. 
grs. 
1 pt. 15 gr. by 60 gr. or 4 pts. ale. at 80° total ext. 1-90 
" 60 : ' 4 " 56 H 2-35 
" 75 " 5 " id. " 2*46 
" 90 " 6 " id. " 2-49 
" 75 " 5 u 45 " 2-50 
" 90 " 6 « id. " 2-44 
We see, in this case, that alcohol at 80° dissolves less 
matter than alcohol at 56°, and that five parts of the latter 
dissolve rather more than four. Which of these solvents 
has dissolved the greatest quantity of the active principle ? 
Atropine is extremely soluble in concentrated alcohol ; 
but we also know that this active principle also exists in the 
plant in a state of combination, perfectly soluble in water; 
on this account, alcohol, at 56°, has been admitted by the 
Codex in the preparation of this tincture. Besides, the tinc- 
ture prepared with alcohol at 80° is green, and consequent- 
ly, loaded w T ith chlorophylle, an inert substance ; while the 
other tinctures contain an imperceptible quantity of this 
principle. We also see that there is no sensible difference 
between the quantity^ of extract obtained by means of alco- 
hol at 56° and alcohol at 45°. 
12. Stramonium. 
grs. 
1 pt. 15 gr. by 60 gr. or 4 pt. ale. at 80° total ext. 2-36 
" 60 " 4 " 56 " 3-05 
" 75 " 5 " id. " 3-15 
" 90 " 6 " id. " 3-14 
" 75 " 5 " 45 " 3-95 
" 90 " 6 " id. " 4-10 
The active principle of this substance, as well as that of 
belladonna, on the same account, is extremely soluble in 
water, the Codex, therefore, directs the use of alcohol at 56° 
in the preparation of this tincture. But these experiments 
prove that the difference between the quantity of matter 
