" with a smile, "to say nothing. If the police or
reporters got this, they'd swoop down on the trail and perhaps spoil
everything!"

"But Bernstine or his clerk will hear of the matter sooner or later,"
complained Pendleton. "And the police and reporters will then get in
on the thing anyhow."

"But there will be a delay," said his friend. "And that may be what we
need just now. Perhaps a few hours will mean success. You can never
tell. The best that we could get by explaining matters to Sime would
be a positive identification of Spatola, or the reverse. And we can
get that from him at any time. So you see, we lose nothing by
waiting."

"I guess that's so," Pendleton acknowledged, and again the car started
forward. At the huge entrance to a railroad station they drew up once
more.

Within, Ashton-Kirk inquired for the General Passenger Agent and was
directed to the ninth floor. The agent was a slim little man with huge
whiskers of snowy whiteness, and a most dignified manner.

"Oh, yes," he said, after glancing at the investigator's card. "I have
heard of you, of course. Who," with a little bow, "has not? Indeed, if
I remember aright, this road had the honor to employ you a few years
ago in a matter necessitating some little delicacy of handling. Am I
not right?"

"And I think it was you," said Ashton-Kirk, smoothly, "who provided me
with some very clearly cut facts which were of considerable service."

The little General Passenger Agent looked pleased and smoothed his
beautiful whiskers softly.

"I was most happy," said he.

"Just now," said Ashton-Kirk, "I am engaged in a matter of some
consequence, and once more you can be of assistance to me."

"Sit down," invited the other, readily. "Sit down, and command me."

Both Pendleton and the investigator sat down. The latter said to the
passenger agent:

"I understand that every railroad has a system by which it can tell
which conductor has punched a ticket."

"Oh, yes. A very simple one. You see the hole left by each punch is
different. One will cut a perfectly round hole, another will be
square, still another will be a triangle, and so on, indefinitely."

From his card case, Ashton-Kirk produced the small red particle which
he had found upon the desk of the murdered man.

"Here is a fragment cut from a ticket," he said. "It is shaped like a
keystone. I should like to know, if you can tell me, what train is
taken out by the conductor who uses the keysto