e that they did not themselves
either do the deed or connive at it. They rapidly and rather clumsily
met the situation. The mark was put by Barker's bloodstained slipper
upon the windowsill to suggest how the fugitive got away. They obviously
were the two who must have heard the sound of the gun; so they gave the
alarm exactly as they would have done, but a good half hour after the
event."

"And how do you propose to prove all this?"

"Well, if there were an outsider, he may be traced and taken. That would
be the most effective of all proofs. But if not--well, the resources of
science are far from being exhausted. I think that an evening alone in
that study would help me much."

"An evening alone!"

"I propose to go up there presently. I have arranged it with the
estimable Ames, who is by no means wholehearted about Barker. I shall
sit in that room and see if its atmosphere brings me inspiration. I'm
a believer in the genius loci. You smile, Friend Watson. Well, we shall
see. By the way, you have that big umbrella of yours, have you not?"

"It is here."

"Well, I'll borrow that if I may."

"Certainly--but what a wretched weapon! If there is danger--"

"Nothing serious, my dear Watson, or I should certainly ask for your
assistance. But I'll take the umbrella. At present I am only awaiting
the return of our colleagues from Tunbridge Wells, where they are at
present engaged in trying for a likely owner to the bicycle."

It was nightfall before Inspector MacDonald and White Mason came back
from their expedition, and they arrived exultant, reporting a great
advance in our investigation.

"Man, I'll admeet that I had my doubts if there was ever an outsider,"
said MacDonald, "but that's all past now. We've had the bicycle
identified, and we have a description of our man; so that's a long step
on our journey."

"It sounds to me like the beginning of the end," said Holmes. "I'm sure
I congratulate you both with all my heart."

"Well, I started from the fact that Mr. Douglas had seemed disturbed
since the day before, when he had been at Tunbridge Wells. It was at
Tunbridge Wells then that he had become conscious of some danger. It was
clear, therefore, that if a man had come over with a bicycle it was
from Tunbridge Wells that he might be expected to have come. We took the
bicycle over with us and showed it at the hotels. It was identified at
once by the manager of the Eagle Commercial as belonging to a man named