ON ALCOHOLIC TINCTURES. 
2-9 
considering the small number of the exceptions, in general, 
to adopt five parts of the solvent. 
4. The proportion of alcohol is always sufficient when it 
well covers the matters submitted to its action, when these 
matters are herbaceous, as leaves; but in other cases it is not 
enough. 
I must observe, that whenever the difference between 
the quantity of the matter dissolved by the alcohol of the 
strength of prescribed by the "codex," and that I have em- 
ployed, has been so trifling as to be insignificant, I thought 
it right to adhere to the strength recommended in that for- 
mulary, to avoid almost useless changes. 
EXPERIMENTS. 1. YELLOW BARK. 
1 pt. or 15 grs. by 60 gr. or 4 pts. alcohol at 80° total, ext. of tinct. 1-63 
it 
a 
75 
a 
5 pts. " 
80 id. 
1-55 
a 
i. 
id. 
a 
id. 
id. 
1-59 
a 
a 
90 
a 
6 pts. " 
id. 
« 
1-47 
ft 
75 
a 
5 " " 
70° 
1-42 
a 
a 
60 
u 
4 « a 
56° 
ct 
1-43 
u 
75 
a 
5 " « 
id. 
a 
1-74 
it 
a 
90 
a 
6 " « 
id. 
a 
1-68 
a 
75 
4 « » 
45° 
u 
1-50 
it 
a 
90 
a 
6 " « 
id. 
a 
1-78 
The quantity of the akaloi'ds was ascertained in the manner 
I have already described. 
150 grammes of the tincture, with 1 part of bark to 5 parts 
alcohol at 80° weight of precipitate, . . . 2*451 
150 grains of tinct. with 1 pt. bark and 5 pts. alcohol, at 
56°, ... . . . . . 0*696 
The first calculation made under different circumstances, gave 
for alcohol at 80°, 1-797 
And for alcohol at 56°, . . . . . 2-641 
We see, by these results, that alcohol at 80°, although it 
does not contain the largest quantity of extract, removes, 
however, a much larger amount of the active principle than 
weaker alcohoL 
3* 
