Twenty grains of Magnesia, and the same quantity of chalk, were
separately neutralized with distilled vinegar, and their effects on ox
gall compared with that of thirty grains of the artificial Epsom salt
dissolved in a sufficient quantity of water. The bile in this solution
became putrid in about sixty hours. That in the solutions made in the
vegetable acid retained its sweetness for several days longer.
These experiments, which terminated so very differently from what I had
expected, seem to justify, in some degree, the practice of giving the
testaceous and absorbent medicines in fevers of a putrescent type, at
the same time that they point out some of that class which ought to
be avoided, and evince how fallacious a method it is to judge of the
effects of medicines _a priori_.
As the bile is, by many, supposed to be the great source of putrid
diseases, ought not the antiseptics which may be prescribed in these
cases, to be such as more particularly impede the corruption of this
fluid, rather than that of flesh?
On account of the superiour antisepticity of the calcined Magnesia
to most of the absorbents, and its greater purity and solubility,
together with the probability of its acting as an evacuant, as well as
a corrector of putrid bile, does it not appear to merit a preference
to all other medicines of this class?
In diseases where an acid cacochymy prevails, and an alkalescent diet,
such as wild fowl, fish, &c. is prescribed, but from the scarcity of
these articles in some countries, cannot be complied with; may not
taking Magnesia or the testaceous powders, immediately before or after
meal time, coincide with this intention, by increasing the putrefactive
fermentation of other animal food in the stomach, which in these
disorders is almost totally subdued by the superabundant acid?
But where animal food is used in putrescent diseases, either through
necessity, or the obstinacy of the patient, ought not Magnesia, in an
uncalcined state, and all the calcareous and testaceous earths to be
carefully abstained from?
Dr. Percival, in a volume of very ingenious experiments and
observations which have been before referred to, has mentioned a
physician of his acquaintance, who always observed his stools to be
more particularly offensive after having taken Magnesia. Might not
this proceed from the action of the Magnesia on the animal food he had
eaten; and is it not reasonable to suppose that the effect might have
been very different where a vegetable or milk diet had been used, as is
generally the case in putrid fevers, and in young children?
I know a person whose stools are, in common, very little tinged with
bile, who after taking calcined Magnesia, evacuates fæces of a very
bilious appearance, though less foetid than usual. It is a fact
worthy of observation, that in the experiments which were made with
calcined Magnesia and bile, the latter was absorbed by, and had united
with the former; and another remarkable circumstance was, that the
watery part of all the mixtures which resisted putrefaction, acquired a
very pungent, saline taste.