What does it say that I read the opium chapter this night, after having woken up at 4:00AM (against all habit)?
I can see the temptation in using Sad Cypress as the anchor book for this chapter, and I'm glad Harkup gave an unambiguous spoiler warning this time around before proceeding to give away the final twist, in order to be able to address a compound that Christie uses in this novel (and which she only mentions by name in Poirot's final round-up of the suspects). Still, it's not like this is the only book by Christie where morphine plays a prominent role, and Harkup would have been able to do without a spoiler completely by choosing, say, By the Pricking of My Thumbs (which was likely inspired by one of the real life cases Harkup addresses anyway), discuss morphine, heroin / diamorphine and codeine exactly the way she does here, and then, without specifically identifying Sad Cypress, tag on a paragraph beginning with "In another book, the poisoner ..." -- and then proceed to describing the solution of Sad Cypress. Ah, well. But, as I said, at least this time around there's a clear spoiler warning ... which should absolutely be heeded by anybody who hasn't read Sad Cypress yet.
Notes on the previous chapters:
I'm now wondering whether the murderer in Ellis Peters's Monk's Hood would really have made it all the way to being found out by Brother Cadfael, a considerable time after the murder, without suffering the slightest effects of the drug himself.
And while I thought I couldn't possibly be more scared of both nicotine and opiates than I already am anyway, just reading about the chemistry involved all over again was a not-very-much-needed refresher of just how scary these really are. And, um, why kicking the habit (smoking) once and for all some 20 years ago was definitely the right thing to do.
Oh, FIE. Major spoiler alert.
In the "Hemlock" chapter, Harkup gives away -- without any prior warning whatsoever -- the identity of not one but two of the key suspects in Five Little Pigs who ultimately turn out to be innocent, and she also reveals the answer to the question that Poirot is chiefly asked to resolve. This concerns persons whom Christie builds up as particularly "promising" suspects with great skill throughout the novel, with many clues pointing in their direction, and the revelation that they are innocent (and how the clues pointing to them are actually red herrings, and what they really mean) is a key part of Poirot's eventual summing up. Even worse, knowing that -- and why -- these two persons didn't do it, and what the clues pointing to them actually mean, opens up direct lines of reasoning pointing to the true killer (whom Harkup doesn't reveal, but who is fairly easy to identify once you start questioning / rethinking those clues -- or at the very least, Harkup's hints also help eliminate other suspects).
If you haven't read Five Little Pigs yet, I strongly suggest you don't read the Hemlock chapter of Harkup's book until after you've read the novel. For all I can see so far, there are no cross-references to this chapter with other parts of A Is For Arsenic, so it's not like you're missing anything that you need to know to be able to follow the rest.
I just finished the digitalis chapter -- a fairly fast read, since for once this was one dealing with stuff of which I had at least a working knowledge going in. Christie herself discusses some of the basics re: digitalis in Appointment with Death and some of her short stories (most notably, The Herb of Death), and more importantly, one of the key characters in Dorothy L. Sayers's The Unpleasantness at the Bellona Club is a doctor -- the very same doctor who prescribed digitalis to his fellow club member, the victim, for his heart condition, in fact -- and he discusses the workings of digitalis with Lord Peter Wimsey in some detail after they've both "viewed" the body. Sayers was as obsessed as Christie about getting the chemistry of her novels involving poison right (she even co-wrote The Documents in the Case with a chemist, Robert Eustace, and they performed lab tests together to make sure the murder could really have been carried out the way they were, um, plotting it). It's obvious that she'd read up on digitalis as well.
Hmm, The Unpleasantness at the Bellona Club was published in 1928, and the RL case that Harkup thinks may have inspired Christie -- the Marie Becker murders -- happened in 1932. Mme. Becker, for her part, wouldn't happen to have been inspired by Sayers, would she?! At any rate, I'm fairly certain that Sayers was aware of the other case that Harkup mentions (Pommerais / Pauw); though the facts are not identical, there are certain elements of that case that also show up in The Unpleasantness at the Bellona Club.
Harkup recounts the story how Rasputin's enemies allegedly lured him to a lunch featuring
"cake and [Madeira] wine ... said to be laced with enough cynide to kill 'a monastery' of monks, but it left Rasputin unaffected. He was then shot, at least twice, but was still alive and fighting back against his would-be assassins. At this point he was beaten into submission, tied up in a carpet and dropped into the frozen Neva river. His body was recovered two days later, and a post-mortem revealed that he had died from drowning."
"There are a number of theories that might explain what happened that day:
1. His assassins were terrible poisoners and did not put enough cyanide in the food to kill him, or mistook an innocuous substance for cyanide salts.
2. Rasputin suffered from alcoholic gastritis.
3. Suspecting someone might try and poison him, Rasputin dosed himself regularly with small amounts of poison to build up an immunity to a larger, normally letha. dose.
4. The sugary cakes and wine acted as an antidote to the cyanide.
5. The story is made up and rasputin was killed by a single shot to the head fired by a British secret service agent."
The she analyzes options 1 - 4, concluding that
* As no samples were preserved and the story changed several times (gee, where have I seen that happen lately?), option 1 is impossible to either prove or disprove in hindsight;
* Option 2 is "reasonable and based on good science" in theory, but equally impossible to confirm because there is no conclusive proof that Rasputin did suffer from alcoholic gastritis;
* Option 3 -- the so-called Mithridatism, named for the king of Pontus (135–63 BC), who is alleged to have done this very thing -- would have worked for animal venom, but not for cyanide; and
* Option 4, while needing more research, at least sounds "promising" on the basis of the comparatively limited amount of knowledge available to date
... only to end her analysis with:
"The fifth Rasputin theory is, of course, the most likely explanation."