Forgive the intrusion. I found your blog. Hoping you will read this and offer an assessment.
I am researching a reported suicide that took place in the early 20th century. I have an abstract of the autopsy report. I believe the suicide was actually a murder, that the scene was set by the murderer and that cause of death was not by Potassium Cyanide. Here is an excerpt:
"“These two brothers occupied a bedroom and kept house at xxxx. xxxxx was formerly a Roman Catholic priest disposed for immorality. Since leaving the pulpit Fr. xxxxx had been going to the bad, drinking and using his time chiefly in accumulating moral filth to throw at his bishop and other of his clerical brethren. The two were last seen alive at nightfall Dec. 7 by their brother. The latter came by appointment at 2:30 PM Dec. 10 and found the men dead lying in a reposeful altitude on the outside of the bed with their clothes on."
Autopsy: Decomposition in full progress. Blood and tissue fluid suggesting potassium cyanide. No sign of caustic irritant poison in stomach and intestines. Congestion of lungs, liver, spleen and kidneys. Both bodies alike in appearance. Chemical analysis failed to get desired reactions.
A strange case indeed, some thoughts:
As you seem to allude to, ingestion of potassium cyanide in toxic amounts usually causes erosions in the esophagus and stomach. The lack of that finding would cast doubt on ingestion of potassium cyanide in toxic amounts, intentional or not.
Death from cyanide inhalation would require the room being sealed fairly tightly (cloth in the gaps around the door, etc.). In a suicide by cyanide inhalation that “addition” to the room would have been found by the individual who found the bodies and others as they arrived on the scene.
Another point to consider here is that a cyanide death by ingestion or by inhalation is not a pleasant, calm death. To find the 2 victims “lying in a reposeful attitude” would be most consistent with their having been placed in “repose” after death, unless some very “peaceful” toxin/drug was taken. Just to mention something that should be obvious, pairs of people do not die of natural causes peacefully in their sleep next to each other.
The autopsy findings (e.g. organ congestion and the bodies “alike in appearance”) would be quite consistent with a toxin or drug-related death. Not knowing the ambient temperature (hotter temperatures speeding up the process of decomposition), it is possible that a cellular (cytochrome) poison would explain the hastened decomposition (the most common cellular toxins are cyanide and carbon monoxide), but the lack of erosions and lack of room “sealing” would seem to argue against cyanide as the cause of death. It is more likely that the bodies were in a hot enough environment to hasten decomposition (as a teacher of mine used to say: when you hear hoof beats think horses, not zebras).
So, all-in-all, I would agree that potassium cyanide is an unlikely cause of death in this case and, considering the information you provide, murder would be a definite possibility (that should certainly have been further investigated at the time).
Updated: One thing occurred to me after I fired off the reply email: in the early 20th century we really didn’t have all the “very peaceful” drug/toxins that we have today to kill ourselves and others. That, too, would limit many of the suicide options we have today being a cause in this case.