He shook his head.  “I have never made a mistake as to that yet, sir.  I have never confused the spectre’s ring with the man’s.  The ghost’s ring is a strange vibration in the bell that it derives from nothing else, and I have not asserted that the bell stirs to the eye.  I don’t wonder that you failed to hear it.  But I heard it.”

“And did the spectre seem to be there, when you looked out?”

“It was there.”

“Both times?”

He repeated firmly:  “Both times.”

“Will you come to the door with me, and look for it now?”

He bit his under lip as though he were somewhat unwilling, but arose.  I opened the door, and stood on the step, while he stood in the doorway.  There was the Danger-light.  There was the dismal mouth of the tunnel.  There were the high, wet stone walls of the cutting.  There were the stars above them.

“Do you see it?” I asked him, taking particular note of his face.  His eyes were prominent and strained, but not very much more so, perhaps, than my own had been when I had directed them earnestly towards the same spot.

“No,” he answered.  “It is not there.”

“Agreed,” said I.

We went in again, shut the door, and resumed our seats.  I was thinking how best to improve this advantage, if it might be called one, when he took up the conversation in such a matter-of-course way, so assuming that there could be no serious question of fact between us, that I felt myself placed in the weakest of positions.

“By this time you will fully understand, sir,” he said, “that what troubles me so dreadfully is the question, What does the spectre mean?”

I was not sure, I told him, that I did fully understand.

“What is its warning against?” he said, ruminating, with his eyes on the fire, and only by times turning them on me.  “What is the danger?  Where is the danger?  There is danger overhanging somewhere on the Line.  Some dreadful calamity will happen.  It is not to be doubted this third time, after what has gone before.  But surely this is a cruel haunting of me.  What can I do?”

He pulled out his handkerchief, and wiped the drops from his heated forehead.

“If I telegraph Danger, on either side of me, or on both, I can give no reason for it,” he went on, wiping the palms of his hands.  “I should get into trouble, and do no good.  They would think I was mad.  This is the way it would work,—­Message:  ’Danger!  Take care!’ Answer:  ‘What Danger?  Where?’ Message:  ’Don’t know.  But, for God’s sake, take care!’ They would displace me.  What else could they do?”

His pain of mind was most pitiable to see.  It was the mental torture of a conscientious man, oppressed beyond endurance by an unintelligible responsibility involving life.