One end is conical, and there is a small hole at the apex which seems to contain a steel point; the other end is flat, but has in the centre a small square projection such as might fit a watch-key. I notice also a small hole in the side of the cylinder close to the flat end. The thing looks like a miniature shell, and appears to be hollow.”
“It is hollow,” said Thorndyke. “You must have observed that, when I held it up to drain, the water trickled out through the hole at the pointed end.”
“Yes, I noticed that.”
“Now take it up and shake it.”
I did so and felt some heavy object rattle inside it.
“There is some loose body inside it,” I said, “which fits it pretty closely, as it moves only in the long diameter.”
“Quite so; your description is excellent. And now, what is the nature of this projectile?”
“I should say it is a miniature shell or explosive bullet.”
“Wrong!” said Thorndyke. “A very natural inference, but a wrong one.”
“Then what is the thing?” I demanded, my curiosity still further aroused.
“I will show you,” he replied. “It is something much more subtle than an explosive bullet—which would really be a rather crude appliance—admirably thought out and thoroughly well executed. We have to deal with a most ingenious and capable man.”
I was fain to laugh at his enthusiastic appreciation of the methods of his would-be assassin, and the humour of the situation then appeared to dawn on him, for he said, with an apologetic smile—
“I am not expressing approval, you must understand, but merely professional admiration. It is this class of criminal that creates the necessity for my services. He is my patron, so to speak; my ultimate employer. For the common crook can be dealt with quite efficiently by the common policeman!”
While he was speaking he had been fitting the little cylinder between two pads of tissue-paper in the vice, which he now screwed up tight. Then, with the fine metal saw, he began to cut the projectile, lengthwise, into two slightly unequal parts. This operation took some time, especially since he was careful not to cut the loose body inside, but at length the section was completed and the interior of the cylinder exposed, when he released it from the vice and held it up before me with an expression of triumph.
“Now, what do you make it?” he demanded.
I took the object in my fingers and looked at it closely, but was at first more puzzled than before. The loose body I now saw to be a cylinder of lead about half an inch long, accurately fitting the inside of the cylinder but capable of slipping freely backwards and forwards. The steel point which I had noticed in the hole at the apex of the conical end, was now seen to be the pointed termination of a slender steel rod which projected fully an inch into the cavity of the cylinder, and the conical end itself was a solid mass of lead.
“Well?” queried Thorndyke, seeing that I was still silent.
“You tell me it is not an explosive bullet,” I replied, “otherwise I should have been confirmed in that opinion. I should have said that the percussion cap was carried by this lead plunger and struck on the end of that steel rod when the flight of the bullet was suddenly arrested.”
“Very good indeed,” said Thorndyke. “You are right so far that this is, in fact, the mechanism of a percussion shell.
“But look at this. You see this little rod was driven inside the bullet when the latter struck the wall. Let us replace it in its original position.”
He laid the end of a small flat file against the end of the rod and pressed it firmly, when the rod slid through the hole until it projected an inch beyond the apex of the cone. Then he handed the projectile back to me.
A single glance at the point of the steel rod made the whole thing clear, and I gave a whistle of consternation; for the “rod” was a fine tube with a sharply pointed end.
“The infernal scoundrel!” I exclaimed; “it is a hypodermic needle.”
“Yes. A veterinary hypodermic, of extra large bore. Now you see the subtlety and ingenuity of the whole thing. If he had had a reasonable chance he would certainly have succeeded.”
“You speak quite regretfully,” I said, laughing again at the oddity of his attitude towards the assassin.
“Not at all,” he replied. “I have the character of a single-handed player, but even the most self-reliant man can hardly make a post-mortem on himself. I am merely appreciating an admirable piece of mechanical design most efficiently carried out. Observe the completeness of the thing, and the way in which all the necessities of the case are foreseen and met. This projectile was discharged from a powerful air-gun—the walking-stick form—provided with a force-pump and key. The barrel of that gun was rifled.”
“How do you know that?” I asked.
“Well, to begin with, it would be useless to fit a needle to the projectile unless the latter was made to travel with the point forwards; but there is direct evidence that the barrel was rifled. You notice the little square projection on the back surface of the cylinder. That was evidently made to fit a washer or wad—probably a thin plate of soft metal which would be driven by the pressure from behind into the grooves of the rifling and thus give a spinning motion to the bullet. When the latter left the barrel, the wad would drop off, leaving it free.”
“I see. I was wondering what the square projection was for. It is, as you say, extremely ingenious.”
“Highly ingenious,” said Thorndyke, enthusiastically, “and so is the whole device. See how perfectly it would have worked but for a mere fluke and for the complication of your presence. Supposing that I had been alone, so that he could have approached to a shorter distance. In that case he would not have missed, and the thing would have been done. You see how it was intended to be done, I suppose?”
“I think so,” I answered; “but I should like to hear your account of the process.”
“Well, you see, he first finds out that I am returning by a late train—which he seems to have done—and he waits for me at the terminus. Meanwhile he fills the cylinder with a solution of a powerful alkaloidal poison, which is easily done by dipping the needle into the liquid and sucking at the small hole near the back end, when the piston will be drawn up and the liquid will follow it. You notice that the upper side of the piston is covered with vaseline—introduced through the hole, no doubt—which would prevent the poison from coming out into the mouth, and make the cylinder secure from leakage. On my arrival, he follows me on his bicycle until I pass through a sufficiently secluded neighbourhood. Then he approaches me, or passes me and waits round a corner, and shoots at pretty close range. It doesn’t matter where he hits me; all parts are equally vital, so he can aim at the middle of my back. Then the bullet comes spinning through the air point foremost; the needle passes through the clothing and enters the flesh, and, as the bullet is suddenly stopped, the heavy piston flies down by its own great momentum and squirts out a jet of the poison into the tissues. The bullet then disengages itself and drops on to the ground.
“Meanwhile, our friend has mounted his bicycle and is off, and when I feel the prick of the needle, I turn, and, without stopping to look for the bullet, immediately give chase. I am, of course, not able to overtake a man on a racing machine, but still I follow him some distance. Then the poison begins to take effect—the more rapidly from the violent exercise—and presently I drop insensible. Later on, my body is found. There are no marks of violence, and probably the needle-puncture escapes observation at the post-mortem, in which case the verdict will be death from heart-failure. Even if the poison and the puncture are discovered, there is no clue. The bullet lies some streets away, and is probably picked up by some boy or passing stranger, who cannot conjecture its use, and who would never connect it with the man who was found dead. You will admit that the whole plan has been worked out with surprising completeness and foresight.”
“Yes,”