took place in that compartment?"

"Certainly, sir."

We followed the guard, and the moment he had imparted his news there
was a suppressed scream in the carriage. Instantly a lady came out,
followed by a florid-faced gentleman, who scowled at the guard. We
entered the now empty compartment, and Kombs said: "We would like to be
alone here until we reach Brewster."

"I'll see to that, sir," answered the guard, locking the door.

When the official moved away, I asked my friend what he expected to
find in the carriage that would cast any light on the case.

"Nothing," was his brief reply.

"Then why do you come?"

"Merely to corroborate the conclusions I have already arrived at."

"And may I ask what those conclusions are?"

"Certainly," replied the detective, with a touch of lassitude in his
voice. "I beg to call your attention, first, to the fact that this
train stands between two platforms, and can be entered from either
side. Any man familiar with the station for years would be aware of
that fact. This shows how Mr. Kipson entered the train just before it
started."

"But the door on this side is locked," I objected, trying it.

"Of course. But every season ticket-holder carries a key. This accounts
for the guard not seeing him, and for the absence of a ticket. Now let
me give you some information about the influenza. The patient's
temperature rises several degrees above normal, and he has a fever.
When the malady has run its course, the temperature falls to three-
quarters of a degree below normal. These, facts are unknown to you, I
imagine, because you are a doctor."

I admitted such was the case.

"Well, the consequence of this fall in temperature is that the
convalescent's mind turns toward thoughts of suicide. Then is the time
he should be watched by his friends. Then was the time Mr. Barrie
Kipson's friends did _not_ watch him. You remember the 21st, of
course. No? It was a most depressing day. Fog all around and mud under
foot. Very good. He resolves on suicide. He wishes to be unidentified,
if possible but forgets his season ticket. My experience is that a man
about to commit a crime always forgets something."

"But how do you account for the disappearance of the money?"

"The money has nothing to do with the matter. If he was a deep man, and
knew the stupidness of Scotland Yard, he probably sent the notes to an
enemy. If not, they may have been given to a friend. Nothing is more
calculated t