“Try it yourself.”
“But you know—”
“You’re wrong. I don’t know, any more than I know how that fellow got out of the cave,” Jack interrupted.
While he was talking Bob had been examining the window opposite the door.
“No marks of anything here,” he announced. “This screen doesn’t seem to have been moved.”
“Of course it hasn’t. You don’t think that ghost would be as clumsy as all that, do you?”
“But how—”
“Tell me how he got out of the cave and I’ll tell you how that letter got here—maybe.”
“But, Jack, this is serious.”
“You bet your life it is.”