And he related the cases in fuller detail.
“Odd,” said the doctor. “And you think this may turn out the same way. Still, in this case the death can’t very well have been natural—or why these elaborate efforts to cover it up?”
“It wasn’t,” said Parker; “the proof being that—as we now know—the plot was laid nearly two months ago.”
“But the method!” cried Wimsey, “the method! Hang it all—here are all we people with our brilliant brains and our professional reputations—and this half-trained girl out of a hospital can beat the lot of us. How was it done?”
“It’s probably something so simple and obvious that it’s never occurred to us,” said Parker. “The sort of principle you learn when you’re in the fourth form and never apply to anything. Rudimentary. Like that motorcycling imbecile we met up at Crofton, who sat in the rain and prayed for help because he’d never heard of an airlock in his feed. Now I daresay that boy had learnt—What’s the matter with you?”
“My God!” cried Wimsey. He smashed his hand down among the breakfast things, upsetting his cup. “My God! But that’s it! You’ve got it—you’ve done it—Obvious? God Almighty—it doesn’t need a doctor. A garage hand could have told you. People die of it every day. Of course, it was an airlock in the feed.”
“Bear up, doctor,” said Parker, “he’s always like this when he gets an idea. It wears off in time. D’you mind explaining yourself, old thing?”
Wimsey’s pallid face was flushed. He turned on the doctor.
“Look here,” he said, “the body’s a pumping engine, isn’t it? The jolly old heart pumps the blood round the arteries and back through the veins and so on, doesn’t it? That’s what keeps things working, what? Round and home again in two minutes—that sort of thing?”
“Certainly.”
“Little valve to let the blood out; ’nother little valve to let it in—just like an internal combustion engine, which it is?”
“Of course.”
“And s’posin’ that stops?”
“You die.”
“Yes. Now, look here. S’posin’ you take a good big hypodermic, empty, and dig it into one of the big arteries and push the handle—what would happen? What would happen, doctor? You’d be pumpin’ a big air-bubble into your engine feed, wouldn’t you? What would become of your circulation, then?”
“It would stop it,” said the doctor, without hesitation. “That is why nurses have to be particular to fill the syringe properly, especially when doing an intravenous injection.”
“I knew it was the kind of thing you learnt in the fourth form. Well, go on. Your circulation would stop—it would be like an embolism in its effect, wouldn’t it?”
“Only if it was in a main artery, of course. In a small vein the blood would find a way round. That is why” (this seemed to be the doctor’s favourite opening) “that is why it is so important that embolisms—blood-clots—should be dispersed as soon as possible and not left to wander about the system.”
“Yes—yes—but the air-bubble, doctor—in a main artery—say the femoral or the big vein in the bend of the elbow—that would stop the circulation, wouldn’t it? How soon?”
“Why, at once. The heart would stop beating.”
“And then?”
“You would die.”
“With what symptoms?”
“None to speak of. Just a gasp or two. The lungs would make a desperate effort to keep things going. Then you’d just stop. Like heart failure. It would be heart failure.”
“How well I know it … That sneeze in the carburettor—a gasping, as you say. And what would be the postmortem symptoms?”
“None. Just the appearances of heart failure. And, of course, the little mark of the needle, if you happened to be looking for it.”
“You’re sure of all this, doctor?” said Parker.
“Well, it’s simple, isn’t it? A plain problem in mechanics. Of course that would happen. It must happen.”
“Could it be proved?” insisted Parker.
“That’s more difficult.”
“We must try,” said Parker. “It’s ingenious, and it explains a lot of things. Doctor, will you go down to the mortuary again and see if you can find any puncture mark on the body. I really think you’ve got the explanation of the whole thing, Peter. Oh, dear! Who’s on the phone now? … What?—what?—oh, hell!—Well, that’s torn it. She’ll never come back now. Warn all the ports—send out an all-stations call—watch the railways and go through Bloomsbury with a tooth-comb—that’s the part she knows best. I’m coming straight up to Town now—yes, immediately. Right you are.” He hung up the receiver with a few brief, choice expressions.
“That adjectival imbecile, Pillington, has let out all he knows. The whole story is in the early editions of the Banner. We’re doing no good here. Mary Whittaker will know the game’s up, and she’ll be out of the country in two twos, if she isn’t already. Coming back to Town, Wimsey?”
“Naturally. Take you up in the car. Lose no time. Ring the bell for Bunter, would you? Oh, Bunter, we’re going up to Town. How soon can we start?”
“At once, my lord. I have been holding your lordship’s and Mr. Parker’s things ready packed from hour to hour, in case a hurried adjournment should be necessary.”
“Good man.”
“And there is a letter for you, Mr. Parker, sir.”
“Oh, thanks. Ah, yes. The fingerprints off the cheque. H’m. Two sets only—besides those of the cashier, of course—Cousin Hallelujah’s and a female set, presumably those of Mary Whittaker. Yes, obviously—here are the four fingers of the left hand, just as one would place them to hold the cheque flat while signing.”
“Pardon me, sir—but might I look at that photograph?”
“Certainly. Take a copy for yourself. I know it interests you as a photographer. Well, cheerio, doctor. See you in Town some time. Come on, Peter.”
Lord Peter came on. And that, as
