Science and the Criminal

by C. Ainsworth Mitchell

The effect of antimony is very similar, and it was owing to this fact that it was possible in the Chapman poisoning case to prove that some of the victims had been poisoned with antimony.

Organic poisons such as prussic acid and vegetable alkaloids are much less stable in character, though they are not so fugitive as some poisoners have supposed, and the presence of alkaloidal poisons in the system has been proved months after death.

In the celebrated Palmer case, to which reference has already been made, Palmer, who was a doctor, made use of strychnine, and, although he was convicted upon the medical and other evidence, Taylor, the official analyst, was unable to detect the poison in the remains. On these grounds and the evidence of other chemists who asserted that they could detect the slightest trace of strychnine, and that had that poison been given it must have passed into the system, the defence was set up that no strychnine had been given, and that the prisoner was entitled to an acquittal.

All that can be fairly deduced from the chemical evidence, however, is that no very large amount of strychnine was present, and that the method of separating alkaloids used by Taylor half a century ago was not capable of detecting traces of strychnine. So far, then, as regards chemical analysis, Palmer had succeeded in administering a poison in sufficient quantity to kill, but to escape detection.

With the more delicate methods of analysis now at the disposal of the chemist this would no longer be possible, for it has been repeatedly proved that it is possible to detect a minute trace of that alkaloid in the body many months after death.

The other details of this case are interesting as forming a very complete chain of evidence.

Palmer, as has been mentioned, was a medical man living at Rugeley, where he had formerly had a practice. For some time prior to the trial he had given up medicine and devoted himself to horse-racing, with the result that he had lost heavily, and by the summer of 1855 owed about £20,000, which he had borrowed at an exorbitant rate of interest from different moneylenders.

As security for these amounts he had given promissory notes, in which he had forged the signature of his mother. It was his intention to have paid the most pressing of his creditors out of the proceeds of an insurance upon the life of his brother, who died in August of the same year.

The insurance company, however, from certain circumstances that had reached their ears, had a suspicion of fraud in connection with this policy, and refused to pay the sum insured.

The holders of the bills, therefore, prepared writs against Palmer and his mother, which were to be issued unless they received the promised money, and it was, therefore, a matter of urgency for Palmer to find a means of satisfying them.