Harley stared at him uncomprehendingly.  “More than ever I fail to understand.”

“I can only ask you to be patient, Mr. Harley.  Time is a wonderful doctor, and I don’t say that in seven years the old wound hasn’t healed a bit.  But to-night you have, unknowingly, undone all that time had done.  I’m a man that has been down into hell.  I bought myself out.  I thought I knew where the pit was located.  I thought I was well away from it, Mr. Harley, and you have told me something tonight which makes me think that it isn’t where I supposed at all, but hidden down here right under our feet in London.  And we’re both standing on the edge!”

That Nicol Brinn was deeply moved no student of humanity could have doubted.  From beneath the stoic’s cloak another than the dare-devil millionaire whose crazy exploits were notorious had looked out.  Persistently the note of danger came to Paul Harley.  Those luxurious Piccadilly chambers were a focus upon which some malignant will was concentrated.  He became conscious of anger.  It was the anger of a just man who finds himself impotent—­the rage of Prometheus bound.

“Mr. Brinn!” he cried, “I accept unreservedly all that you have told me.  Its real significance I do not and cannot grasp.  But my theory that Sir Charles Abingdon was done to death has become a conviction.  That a like fate threatens yourself and possibly myself I begin to believe.”  He looked almost fiercely into the other’s dull eyes.  “My reputation east and west is that of a white man.  Mr. Brinn—­I ask you for your confidence.”

Nicol Brinn dropped his chin into his hand and resumed that unseeing stare into the open grate.  Paul Harley watched him intently.

“There isn’t any one I would rather confide in,” confessed the American.  “We are linked by a common danger.  But”—­he looked up—­“I must ask you again to be patient.  Give me time to think —­to make plans.  For your own part—­be cautious.  You witnessed the death of Sir Charles Abingdon.  You don’t think and perhaps I don’t think that it was natural; but whatever steps you may have taken to confirm your theories, I dare not hope that you will ever discover even a ghost of a clue.  I simply warn you, Mr. Harley.  You may go the same way.  So may I. Others have travelled that road before poor Abingdon.”

He suddenly stood up, all at once exhibiting to his watchful visitor that tremendous nervous energy which underlay his impassive manner.  “Good God!” he said, in a cold, even voice.  “To think that it is here in London.  What does it mean?”

He ceased speaking abruptly, and stood with his elbow resting on a corner of the mantelpiece.

“You speak of it being here,” prompted Harley.  “Is it consistent with your mysterious difficulties to inform me to what you refer?”

Nicol Brinn glanced aside at him.  “If I informed you of that,” he answered, “you would know all you want to know.  But neither you nor I would live to use the knowledge.  Give me time.  Let me think.”