July 8, 1871.] 
THE PHARMACEUTICAL JOURNAL AND TRANSACTION?. 
25 
and the moistened powder put through a sieve of about 
twelve meshes to the inch before the packing. The 
packing and percolating was then done with all the care 
and skill which the writer’s experience could suggest, so 
that the results are considered to be much better than an 
average practice would give. Each pint of percolate 
was weighed in a flask marked in the narrow part of the 
neck, and the menstruum at the same temperature was 
weighed in the same flask, and the difference in weight 
set down in the column under that heading. The same 
powder, managed in the same way, was percolated at 
once; and another portion, after macerating four days, 
with no practical difference in result; whilst a macera¬ 
tion of twenty-four hours after the third or fourth pint 
of percolate had passed, would always increase the dif¬ 
ference somewhat, and would often increase them much. 
Changes of temperature, also, by changing the solvent 
power of the menstruum, caused the differences to rise 
and fall somewhat, coincident with changes of weather. 
A simple inspection of the proportion of the extract con¬ 
tained in the first pint of each percolate will probably 
expose the fallacy that any amount of expert skill and 
management could ever make that pint represent the 
whole efficacy of the drug. In percolating the powder 
of good aconite root by a very slow and careful percola¬ 
tion, the characteristic numbing impression upon the 
tongue was distinctly though faintly perceptible by the 
application of a few drops from the thirteenth pint. The 
bitterness of cinchona was perceptible in the seventeenth 
pint; but neither the taste nor odour of wild cherry 
bark were perceptible in the sixteenth pint, though the 
amount of extract contained was large. Ergot was ne¬ 
cessarily percolated in coarse powder (No. GO), and was 
easily and rapidly exhausted; but the dried residue pow¬ 
dered finer gave a notable proportion of extract, which, 
for want of time, was not determined. Not so with 
lupulin, however, which, percolated in its natural con¬ 
dition of coarse powder, left a light residue, from which 
no ordinary management could extract anything more. 
The percolation of lupulin was very regular and uniform, 
and maceration at any stage of the process had no per¬ 
ceptible effect. Effective percolations of dandelion-root 
are very slow, and therefore very perfect; and like those 
of sarsaparilla, often become slower as they approach 
completion. 
The great difference in the rate of exhaustion in the 
studied by itself, 
paper, the solid e 
Erom results given in a previous 
medicinal value as found in different parts of the per¬ 
colate, but becomes weaker towards the end. When this 
ceases to be of practical value, or, in other words, where 
the percolation should terminate, was not determined. 
Among the examples given it will be seen that if the 
Pharmacopoeia used fine powder and slow percolation, it 
would, in the case of dandelion, obtain 86 per cent, of; 
the total extract; and it is probable that this is some¬ 
where near or beyond the limit of practical utility. If 
so, it might be directed that fluid extracts as a class of 
preparations should not contain less than 80 per cent, of 
the total solid extract which the drugs were capable of ; 
yielding to the given menstruum; and the limit of per¬ 
colation necessary to obtain this is shown by one of the 
linos of the table. But where this 80 per cent, of the 
solid extract has been obtained, it is not within the com¬ 
pass of a pint, but is contained in a number of pints, 
never less than nor more than 11. 
To get these various large quantities within the mea¬ 
sure of a pint each without the use of heat, and with the 
least loss of menstruum, is the next and great requisite, 
without which they are not fluid extracts. 
To accomplish this, there appears to be no choice of 
means. There is one way, and only one way, known to 
the writer by which it may be done, and that is by re¬ 
percolation, or percolating fresh portions of the drug 
with percolate from previous portions, until the normal 
difference in weight between equal volumes of the men¬ 
struum and percolate is attained. 
This process is somewhat complex and troublesome, 
and requires knowledge and skill; and, worse than all, 
requires that a stock of weak percolate of different densi¬ 
ties be carried from one making to the next for each fluid 
extract. But, as it appears to be absolutely the only 
means of accomplishing the end well and properly, there 
is no choice between it and those means which give re¬ 
sults too imperfect for the present state of pharmacy. 
[To be continued .) 
GLYCERINE; ITS QUALITY AS IT EXISTS IN 
COMMERCE. 
BY JOSEPH P. REMINGTON, PHILADELPHIA. 
This powerful solvent and useful medicine, though but 
lately called from its seclusion in the cabinet in answer 
to the demands of this progressive age, has rapidly in¬ 
gratiated itself into the esteem of the chemist, pharma¬ 
cist, and the public at large. 
It continues to widen its sphere of usefulness; we hear 
of new applications constantly ; and its bland manners 
and insinuating disposition have won for it a host of 
friends, and an ever-increasing popularity. 
It serves its mission as faithfully on the dressing-table 
of a lady as it does in our gas meters ; as well as an ex¬ 
cipient for pill-masses as it does as a substitute for molasses 
in printers’ rollers, and its range of applications between 
these extremes is varied and extensive. 
Its production, with a view to improve the quality and 
lower the price, has been attended with success, as we 
all know. A glycerine which will answer almost every 
purpose (except for internal administration), can be pro¬ 
cured for twenty-five cents per pound; and one fit for 
any purpose for sixty cents per pound. 
One of the principal reasons for bringing this matter 
forward, is to detail a comparative examination of the 
different brands in the market, which examination was 
at first undertaken for the writer’s own satisfaction, but 
which may prove not uninteresting to the Association. 
1 
I | rTj 
j ns 
p 
? 
II « 
For Strength. 
Sp. Gr. 
% 
Colour. 
Odour when 
warm. 
Nitrate of 
Silver. 
l 
1-253 
None. 
None. 
No precip. 
0 
1-240 
Yellowish. 
Fatty. 
Heavy wh. pre. 
3 
1-250 
Yellowish. 
Slight. 
Hose colour. 
4 
1-254 
None. 
Empyreumatie. 
No precip. 
5 
1-250 
Quite dark. 
Like glue. 
White precip. 
6 
1-245 
None. 
Slight. 
Eose colour. 
Brands. 
Sulphuric 
Acid. 
For Sulphate 
of Lime. 
For Lime Salts 
Ox. Ammon. 
Ferrocyanide 
of Iron. 
1 
j 
1 
1 
O 
3 
4 
5 
6 
Slightly discol. 
Discoloured. 
Discoloured. 
Discoloured. 
Slightly discol. 
Discoloured. 
No precip. 
No precip. 
No precip. 
No precip. 
No preeip. 
No precip. 
No precipitate. 
Slight precip. 
No precipitate. 
No precipitate. 
White precip. 
No precipitate. 
Opalescence. 
Clear. 
Opalescence. 
Precipitate. 
Slight precip. 
No precip. 
OC 
rj 
Q 
C5 
u 
« 
ITydro-sulph. 
of Ammon. 
Chloride of 
Barium. 
For Ethyl- 
Butyrate. 
For Sugar. 
1 
2 
3 
4 
5 
G 
No precip. 
No precip. 
No precip. 
No precip. 
No precip. 
Slight precip. 
No precip. 
Slight precip. 
Precipitate. 
No preeip. 
Opalescent. 
No precip. 
Slight odour. 
Strong odour. 
Slight odour. 
Veryslight odour 
Slight odour. 
Slight odour. 
Free fr. sugar. 
Free fr. sugar. 
Free fr. sugar. 
Free fr. sugar. 
Free fr. sugar. 
Free fr. sugar. 
