“Ah!” Roger grinned. “Well, I’m one up on you there at any rate. Look at this!” He drew the little handkerchief out of his pocket-book, tossed it over to the other and explained how it had come into his possession.
“Yes,” agreed the inspector with a rueful air. “Yes, you’re certainly one up on me there, Mr. Sheringham.”
“That’s good,” said Roger with undisguised satisfaction. “Well, to continue. Apart from the information about Mrs. Vane’s visit, two other facts emerged: one, that Meadows changed his pipes once a week, to which no significance appears to attach, the other, that he was a very small smoker—and that’s very important indeed. I found out from the village shop, you see, that he bought a quarter-of-a-pound at a time, but only smoked it at the rate of an ounce a week. As he evidently emptied the whole lot into that tobacco-jar in his room which you sent away to be analysed, that would mean that the bottom contents of the jar would remain in place for between three and four weeks. For anybody conversant with his habits, this knowledge might be very useful indeed.”
The inspector nodded slowly. “Very ingenious, sir; very ingenious.”
“Glad you think so, Inspector,” Roger smiled. “I’m quite sure that praise from you is praise worth having. Well, that’s my theory. Mrs. Vane and Meadows, to cut a long story short, were both planning to murder each other. Meadows believed in direct methods; Mrs. Vane was more painstaking. Both their motives are obvious, I think. Meadows had been threatening her with exposure, no doubt, if she didn’t satisfy his financial demands, which, as Mrs. Vane with her knowledge of the type must have realised, would gradually grow bigger and bigger. She had retaliated by threatening to inform the police of his whereabouts, knowing that he was badly wanted by them on more than one charge. The result was that both had succeeded in thoroughly frightening the other, and each decided on the other’s elimination as the only escape from an intolerable situation. That’s perfectly reasonable, I think?”
“Perfectly,” assented the inspector at once.
“Damned cunning,” commented Anthony warmly.
“Thank you, Anthony. Well, as I said, Mrs. Vane was the more painstaking of the two. She elaborated her plan with, I think, considerable ingenuity. Her knowledge of poisons, you see, was probably two-fold; her father was with a firm of wholesale chemists, you said, and she might well have picked up a few tips from him, apart from what she could have got out of her husband’s books. She knew enough at any rate to recognise aconitine as pre-eminently her requirement. And she hit upon poison in the first place, I should have said, because she had an unlimited supply of all brands ready to her hand. What did she do, then? Simply this: having made an excuse for visiting her real husband’s rooms (necessarily in circumstances of profound secrecy), she sent him out of the room on some pretext, slipped the stuff into the bottom of his tobacco-jar, and went calmly away to await developments.”
“Which turned out to be somewhat different from what she’d expected,” supplied the inspector.
“Very much so. But of course she thought she was on velvet. She knew the fact of her having been to Meadows’ rooms that night would never leak out, because it was to his advantage to keep quiet about it (though it certainly was short-sighted of her to talk loudly enough to waken the landlady); and having placed the poison at the bottom of the jar, with two or three ounces of harmless stuff on top of it, she knew that it would be at least a fortnight before he would reach it, and by that time she would be miles away with a complete alibi established.”