person who is proved to have administered poison. When the
administration is proved, little evidence is in general required to
establish the intent. It is sufficient that the giver knew the substance
administered was of a deadly nature; and in regard to any of the common
poisons this knowledge is sufficiently constituted by his simply knowing
its name.
In some cases, however, the exact nature of the poison is not
established with certainty; and then something else may be required to
prove the prisoner’s knowledge, and through that knowledge his intent.
In the case of Charles Munn, formerly alluded to [p. 50], arsenic was
the poison presumed to have been taken by the deceased. But the purchase
or possession of it by the prisoner was not for some time satisfactorily
established; neither was there any chemical evidence, the deceased
having lived forty days and upwards after taking the poison. It was
proved, however, that whatever it was which had been administered, the
prisoner knew very well that what he gave was deleterious; because he
persuaded the deceased, who was pregnant by him, to take it by assigning
to it properties which no drug either possesses, or is so much as
thought by the vulgar to possess. On one occasion he persuaded her that
it would show whether she was with child, and on another that it would
prevent people from knowing she was with child. In such cases, then,
good evidence may be derived from the arguments used by the giver to
persuade his victim to take the poison; and sometimes, as in the
instance now mentioned, it will lie with the medical witness to inform
the court whether or not the reasons assigned are false.
Sometimes it has been pleaded by the prisoner that he gave the poison by
mistake. In all such cases, if he descends to particulars, which he
cannot help doing, there is every likelihood that the falsehood of the
defence will be made evident by the particulars of the story not
agreeing with other particulars of the moral or medical evidence. At
present it is only necessary to allude to inconsistencies in his story
with the medical facts. No general rules can be laid down on the method
of investigating a case with a view to evidence of this kind: I must be
satisfied with an illustration from an actual occurrence. On the trial
of Mr. Hodgson, a surgeon, at the Durham Autumn Assizes in 1824, for
attempting to poison his wife, it was clearly proved, that pills
containing corrosive sublimate, and compounded by the prisoner, were
given by him to her in place of pills of calomel and opium, which had
been ordered by her physician. But it was pleaded by him, that, being at
the time intoxicated, he had mistaken, for the shop-bottle which
contained opium, the corrosive-sublimate bottle which stood next it.
This was certainly an improbable error, considering the opium was in
powder, and the sublimate in crystals. But it was not the only one which
he alleged he had committed. Not long after his wife took ill, the
physician sent the prisoner to the shop to prepare for her a laudanum
draught, with water for the menstruum. When the prisoner returned with
it, the physician, in consequence of observing it to be muddy, was led
to taste it, before he gave it to the sick lady: and finding it had the
taste of corrosive sublimate, he preserved it, analyzed it, and
discovered that it did contain that poison. The prisoner stated in
defence, that he had a second time committed a mistake, and instead of
water had accidentally used for the menstruum a corrosive-sublimate
injection, which he had previously prepared for a sailor. This was
proved to have been impossible; for the injection contained only five
grains to the ounce, while the draught, which did not exceed one ounce,
contained fourteen grains.[129]
I believe it must be allowed, that, as the medical inquiries preparatory
to trial are commonly conducted without the inspector being made
acquainted with the moral circumstances in detail, it is rarely possible
for him to foresee what points should be attended to, with the view of
illustrating the intent. But the case now related will show that it is
impossible for him to render his inquiries too minute or comprehensive;
and more particularly, it shows the propriety of ascertaining, whenever
it is possible, not only the nature but likewise the quantity of the
poison.