Axnil 5, 1873.] 
THE PHARMACEUTICAL JOURNAL AND TRANSACTIONS. 
733 
This infusion was prescribed as a stimulant in 
paralysis. 
In a paper read before this Society in 1845 (Pharm. 
Journ. Vol. V. 1st series, p. 62), I directed attention 
to the fact that if this infusion be made with boiling 
water, care being taken that the vessel used is of the 
same temperature, the result will be quite devoid ol 
pungency, and consequently without value as a the¬ 
rapeutic agent. I then stated that “it is of the 
utmost importance that the laws which govern the 
formation of this volatile oil should be well under¬ 
stood.” This infusion has been omitted since the 
Pharmacopoeia of 1851. 
We now arrive at the British Pharmacopoeia, and 
find that both black and white mustard continue 
official, and that there is a further slight alteration, 
not in the ingredients or their proportions, but in the 
directions for making the mustard cataplasm. 
Cataplasma Sinapis. 
Take of— 
Mustard in powder . . . . 2| oz. 
Linseed Meal.oz. 
Boiling Water.10 fluid oz. 
Mix the linseed meal gradually with the water, and add 
the mustard with constant stirring. 
The alteration here is, that the linseed meal is first 
mixed with water and the mustard added afterwards, 
the temperature being thus reduced. This is another 
step in the right direction, and I shall have occasion 
by-and-bye to refer to it again. 
Black mustard contains two proximate principles, 
myrosin and myronic acid, the latteri n combina¬ 
tion with potash, and it is to their mutual reaction 
that the formation of the volatile oil is due. Myro¬ 
sin is an albuminous substance, soluble in cold and 
in lukewarm water, but coagulated by heat, alcohol, 
and acids. Here we have a reason for the successive 
alterations in the mustard cataplasm. 
If black mustard flour be mixed with cold water, 
or water at a temperature below 100° F., the whole 
of the volatile oil it is capable of yielding may be 
obtained from it. If the temperature of the water 
be 140° or thereabouts, it does not yield more than 
half the quantity, and at 180° very little oil can be 
distilled from it. These variations are due to the 
partial or entire coagulation of the myrosin present. 
In making the cataplasm of the British Pharmaco¬ 
poeia, I find that when the linseed meal is added to 
the boiling water the temperature is reduced to 180°, 
and after the addition of the mustard to 160°. Either 
of these temperatures is too high for the full deve¬ 
lopment of the volatile oil. 
I would suggest here an alteration in the direc¬ 
tions. Let the mustard be first mixed with two 
or three ounces of water under 100° or lukewarm. 
Boil the remaining part of the water, with , which 
mix the linseed meal, and add this to the mustard, 
which has had time to develop its pungency. The 
temperature of the cataplasm will then be about 120°. 
It will be found at once fully efficient and about 
double the strength of that made by the present for¬ 
mula ; and this, in many instances, may be of the 
utmost importance. 
It is the speedy action which gives to a mustard 
poultice an advantage over a blister. 
Mustard flour has never, I believe, been prepared 
by the pharmacist for medicinal use, and I may as¬ 
sume that this is never likely to be done in the phar¬ 
macy. Its preparation will be left to the manufac¬ 
turer, who has special appliances for the purpose. 
In reference to this part of the subject, I cannot do 
better than quote the concise description of Dr. Pe¬ 
reira :— u The seeds of both black and white mustard 
are first crushed between rolls, and then pounded in 
mortars. The pounded seeds are then sifted. The 
residue in the sieve is called dressings or siftings; 
what passes through is impure flour of mustard. 
The latter by a second sifting yields pure flour of 
mustard and a second quantity of dressings. By 
pressure, the dressings or siftings yield a fixed oil 
(fixed oil of mustard), which is used for mixing with 
rape and other oils.” 
The black and white mustard seeds are crushed 
separately, and then mixed in definite proportions. 
There is a special object in this to which I shall have 
occasion again to allude. The fixed oil has some re¬ 
putation as an external remedy in rheumatism, due 
probably to a little volatile oil developed in it ; but 
the demand is very limited, the bulk of it melts away 
into the rape oils of commerce, and the marc, as a 
solid cake, is sold for manure, and report says that it 
sometimes finds its way accidentally ( ?) into linseed 
cake. Formerly, when black pepper paid a duty, 
this mustard bran or dressings was extensively used 
in its adulteration. Through the courtesy of Messrs. 
Dewar and Sons, mustard manufacturers, of New- 
castle-on-Tyne, I am enabled to place on the table 
samples of genuine mustard flour. I have here 
black mustard flour, white mustard flour, brown 
and white mixed, and another sample of the same 
from which a further portion of the husk has been 
sifted,* and also husks to which the name of dressings 
has been applied, and from which the fixed oil is 
expressed ; a sample of the fixed oil and of the 
mustard cake are likewise on the table. 
The question will naturally occur, why mix white 
with black seeds ? The explanation is this. The 
quantity of myrosin in the black mustard seed is 
not sufficient for the decomposition of all the myro- 
nate of potassium present, and as the white mustard 
seed contains a large quantity of myrosin and no 
myronate of potassium, it is added with advantage 
and economy. If water be added to pure flour of 
black mustard seed, the essential oil allowed to form 
and then removed, a further addition, of flour of 
white mustard seed will again give rise to more 
essential oil, and thus prove that all the myronate 
has not been decomposed by the quantity of myro¬ 
sin naturally present in the black seed; and I be¬ 
lieve that by decomposing this excess of myronate of 
* In a letter received from Mr. Frazer respecting this 
latter article he says :— 
“ It must now be some twenty or twenty-five years since 
we adopted Dewar of Newcastle’s pure brown mustard as 
the sole article of mustard kept by my firm m Glasgow. 
For two or three years we had to fight against a widespread 
prejudice in the public mind against its deeper colour than 
that of the article commonly in use, as also against the 
dark specks present in it. 
“ Finding this prejudice to be so strong as practically to 
render the sale of it almost impossible, I suggested to Mr. 
Dewar so to modify, if practicable, his process of manu¬ 
facture, as to reduce the amount of dark specks to a 
minimum. . ,._» 
“ Mr. Dewar did so, and the result was the production ot 
a mustard at once absolutely genuine, and yet so near to 
the colour of that in ordinary use, that at length we were 
able to induce the public to give it a fair trial. 
“ Since then we have kept nothing but the pure article, 
and the results are such as amply to compensate us for the 
patience we had to exercise in its introduction. 
