EXTRACTS OF THE BRITISH PHARMACOPOEIA. 
305 
The extract of calumbo being a novelty in the British Pharmacopoeia, I 
have selected it as the first upon which to say a few words, and in order that 
I may be as clear as possible, I must trespass upon you the form and process 
as laid down in the British Pharmacopoeia. Take of calumbo, in powder, one 
pound, proof spirit, four pints ; macerate the calumbo in two pints of the 
spirit for twenty-four hours ; pack in a percolator, and pass the remainder of 
the spirit slowly through it, distil off the spirit, and evaporate the residue to 
a proper consistence. This extract has probably been taken from the Prus¬ 
sian Pharmacopoeia, but unfortunately whilst borrowing the idea and the 
proportions, the compilers of our national Pharmacopoeia have forgotten to 
copy the directions. Now the first and perhaps principal point to be noticed 
in the process given is this, that having macerated the calumbo in the first 
portion of the spirit, and having packed in the percolator, and poured on the 
remainder of the spirit, and having allowed as much of the spirituous liquor 
or tincture to pass through as will, there is no direction given for displacing 
that portion which remains absorbed by the marc, either by a -weaker spirit 
or water, or by the simple operation of expression, as directed in the pre¬ 
paration of tinctures. This was probably an oversight, but nevertheless, what 
are the natural consequences which arise from following such directions P Just 
this : the calumbo is not more than half exhausted, about one-fifth of the 
proof spirit remains absorbed by it, and after distilling off from the tincture 
which has percolated through as much spirit as can be before evaporating the 
residue, there is a loss of something like eighteen ounces of rectified spirit 
out of the fifty used, and a product, after evaporating down, of one ounce and 
a half of extract, in appearance somewhat resembling leather, and at a cost of 
something like two shillings an ounce when made upon a small scale. 
If we now continue our operations upon the marc by passing through it 
some hot water at a temperature of about 160° Fahrenheit, until it passes 
through without much bitterness,—for it is almost impossible entirely to ex¬ 
haust it,—there will be obtained by evaporating the liquid another ounce and 
a half of a somewhat similar extract, but not so tough, making together, three 
ounces, from sixteen ounces of the root employed. 
This simply proves that the Pharmacopoeia process is a wasteful one, and 
does not obtain for the operator all that might be expected. 
Now taking it for granted (and I am not quite satisfied about it) that spirit 
is necessaiy, and proof spirit the best menstruum for exhausting calumbo and 
making a good extract, let sufficient be used, and let all the tincture—for it is 
virtuall} 7- a tincture—be displaced either by pressure or water, previous to the 
second part of the process, that of distilling off the spirit; nearly the whole 
of the spirit might then be recovered, and there can be no valid reason, that 
I know of, why water should not be used for displacing the tincture,—for 
granted that a little mixes up with the spirituous portion in passing through 
the percolator, it cannot in any way injure the product, as water is really, in 
any case, the menstruum which is evaporated down with the extract after the 
spirit has been distilled off 
The next point which I desire you to consider is this : is spirit essential in 
making good extract of calumbo ? I believe it is not. It appears to me that 
there is nothing in the composition of calumbo which requires the use of 
spirit for the extraction of its bitter. According to Planche and Buchner, 
calumbo consists of from 10 to 13 parts of bitter matter, 6 parts of animal 
matter, 9 parts of gum, 33 of starch, and 39 of woody fibre, with a trace of 
volatile oil. The bitter matter is soluble in cold water, and that appears to 
be what is required. I have been in the habit of making extract of calumbo 
by percolation with cold water for some time, and long before the British 
Pharmacopoeia was published ; the product has averaged from two and a half 
