The doctor proceeded at once with his examination.  Mr. Hamilton Fynes, this mysterious person who had succeeded, indeed, in making a record journey, was leaning back in the corner of his seat, his arms folded, his head drooping a little, but his eyes still fixed in that unseeing stare.  His body yielded itself unnaturally to the touch.  For the main truth the doctor needed scarcely a glance at him.

“Is he dead?” the station-master asked.

“Stone-dead!” was the brief answer.

“Good God!” the station-master muttered.  “Good God!”

The doctor had thrown his handkerchief over the dead man’s face.  He was standing now looking at him thoughtfully.

“Did he die in his sleep, I wonder?” the station-master asked.  “It must have been horribly sudden!  Was it heart disease?”

The doctor did not reply for a moment.  He seemed to be thinking out some problem.

“The body had better be removed to the station mortuary,” he said at last.  “Then, if I were you, I should have the saloon shunted on to a siding and left absolutely untouched.  You had better place two of your station police in charge while you telephone to Scotland Yard.”

“To Scotland Yard?” the station-master exclaimed.

The doctor nodded.  He looked around as though to be sure that none of that anxious crowd outside could overhear.

“There’s no question of heart disease here,” he explained.  “The man has been murdered!”

The station-master was horrified,—­horrified and blankly incredulous.

“Murdered!” he repeated.  “Why, it’s impossible!  There was no one else on the train except the attendant—­not a single other person.  All my advices said one passenger only.”

The doctor touched the man’s coat with his finger, and the station-master saw what he had not seen before,—­saw what made him turn away, a little sick.  He was a strong man, but he was not used to this sort of thing, and he had barely recovered yet from the first shock of finding himself face to face with a dead man.  Outside, the crowd upon the platform was growing larger.  White faces were being pressed against the windows at the lower end of the saloon.

“There is no question about the man having been murdered,” the doctor said, and even his voice shook a little.  “His own hand could never have driven that knife home.  I can tell you, even, how it was done.  The man who stabbed him was in the compartment behind there, leaned over, and drove this thing down, just missing the shoulder.  There was no struggle or fight of any sort.  It was a diabolical deed!”

“Diabolical indeed!” the station-master echoed hoarsely.

“You had better give orders for us to be shunted down on to a siding just as we are,” the doctor continued, “and send one of your men to telephone to Scotland Yard.  Perhaps it would be as well, too, not to touch those papers until some one comes.  See that the attendant does not go home, or the guard.  They will probably be wanted to answer questions.”