As a thief in the night

by R. Austin Freeman

“Why a summary?” I objected. “I would rather have it in extenso if it will not weary you to relate it.”

“It will be more likely to weary you,” he replied. “But if you are equal to a lengthy exposition, let us take to our easy chairs and combine bodily comfort with forensic discourse.”

We drew up the two arm-chairs before the hearth, and when Polton had made up the fire and placed between us a small table furnished with a decanter and glasses, Thorndyke began his exposition.

“This case is in some respects one of the most curious and interesting that I have met with in the whole of my experience of medico-legal practice. At the first glance, as I told you at the time, the problem that it presented seemed hopelessly beyond solution. All the evidence appeared to be in the past and utterly irrecoverable. The vital questions were concerned with events that had passed unrecorded and of which there seemed to be no possibility that they could ever be disinterred from the oblivion in which they were buried. Looking back now on the body of evidence that has gradually accumulated, I am astonished at the way in which the apparently forgotten past has given up its secrets, one after another, until it has carried its revelation from surmise to probability and from probability at last to incontestible proof.

“The inquiry divides itself into certain definite stages, each of which added new matter to that which had gone before. We begin, naturally, with the inquest on Harold Monkhouse, and we may consider this in three aspects: the ascertained condition of the body; the evidence of the witnesses; and the state of affairs disclosed by the proceedings viewed as a whole.

“First, as to the body: there appeared to be no doubt that Monkhouse died from arsenical poisoning, but there was no clear evidence as to how the poison had been administered. It was assumed that it had been taken in food or in medicine—that it had been swallowed—and no alternative method of administration was suggested or considered. But on studying the medical witnesses’ evidence, and comparing it with the descriptions of the patient’s symptoms, I was disposed to doubt whether the poison had actually been taken by the mouth at all.”

“Why,” I exclaimed, “how else could it have been taken?”

“There are quite a number of different ways in which poisonous doses of arsenic can be taken. Finely powdered arsenic is readily absorbed by the skin. There have been several deaths from the use of ‘violet powder’ contaminated with arsenic, and clothing containing powdered arsenic would produce poisonous effects. Then there are certain arsenical gases—notably arsine, or arseniureted hydrogen—which are intensely poisonous and which possibly account for a part of the symptoms in poisoning from arsenical wall-papers. There seemed to me to be some suggestion of arsenical gas in Monkhouse’s case, but it was obviously not pure gas-poisoning. The impression conveyed to me was that of a mixed poisoning; that the arsenic had been partly inhaled and partly applied to the skin, but very little, if any, taken by the mouth.”

“You are not forgetting that arsenic was actually found in the stomach?”

“No. But the quantity was very minute; and a minute quantity is of no significance. One of the many odd and misleading facts about arsenic poisoning is that, in whatever way the drug is taken, a small quantity is always found in the stomach and there are always some signs of gastric irritation. The explanation seems to be that arsenic which has got into the blood in any way—through the skin, the lungs or otherwise—tends to be eliminated in part through the stomach. At any rate, the fact is that the presence of minute quantities of arsenic in the stomach affords no evidence that the poison was swallowed.”