These are established facts. Make the assumption that his earlier association with Mrs. Silverdale was a guilty and not an innocent one, and see where that leads. It suggests the following:
(a) That they took special care to conceal their intimacy, since Silverdale would have been glad of a divorce.
(b) That they themselves did not wish for a divorce, possibly for financial reasons.
(c) That Hassendean was utilised as a shield for the real intrigue, without understanding that he was serving this purpose.
(d) That he took the bit in his teeth and resorted to hyoscine to gain his ends.
(e) That Markfield, on his way home from the Research Station that night, caught a glimpse of Hassendean driving Mrs. Silverdale out to the bungalow, and became suspicious.
(f) That he followed them and the tragedy ensued.
(g) That after the tragedy, Markfield realised the danger of his love-letters to Mrs. Silverdale which were in her room at Heatherfield.
(h) That the Heatherfield murder followed as a sequel to this.
Finally, there is the inscription in the ring which Mrs. Silverdale wore. Markfield has no initial "B" in his name; but the "B" might stand for some pet name which she used for him.
The net result of it all is that there are strong grounds for suspicion against him, but no real proof that one could put confidently before a jury.
Possibly he might be bluffed. I’ll try it.
One might put it down as a drawn game. We failed to hang Markfield, for the explosion killed him on the spot. Luckily, the effects were extraordinarily localised, and Flamborough and I got off alive, though badly damaged temporarily.
Markfield, one has to admit, was too clever for us at the last. From what a chemist has since told me, tetranitromethane detonates with extraordinary violence in presence of triethylamine, though it is perfectly safe to handle under normal conditions. Markfield had about half a pound or more of tetranitromethane in his conical flask; in his dropping funnel he had alcohol, or some other harmless liquid, colourless like triethylamine; and in his stoppered bottle he had triethylamine itself. While he talked to us, he ran the alcohol into the tetranitromethane—a perfectly harmless operation. Then, when he saw the game was up, he ran the funnel empty, and refilled it from the bottle. As we saw it, this was simply a preparation for continuing the experiment which we had already found to be harmless; but in practice it meant that he had only to turn his tap and mix the two liquids in order to get his explosion. He staged it so well that neither Flamborough nor I spotted what he was after.
The house was a perfect wreck, they tell me: doors and windows blown out, ceilings down, walls cracked. The room we were in was completely gutted by the explosion; and Markfield was torn in pieces. I didn’t see it, of course. The next thing I remember was waking up in a nursing home. Possibly it was cheap at the price of getting rid of Markfield. He was a good specimen of the callous murderer. The only soft spot in him seems to have been his passion for Yvonne Silverdale.
Alfred Walter Stewart, who wrote under the pen name J. J. Connington, was born in Glasgow, the youngest of three sons of Reverend Dr Stewart. He graduated from Glasgow University and pursued an academic career as a chemistry professor, working for the Admiralty during the First World War. Known for his ingenious and carefully worked-out puzzles and in-depth character development, he was admired by a host of his better-known contemporaries, including Dorothy L. Sayers and John Dickson Carr, who both paid tribute to his influence on their work. He married Jessie Lily Courts in 1916 and they had one daughter.
