"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."