By this time so bewildered had I become that I scarce knew whether to descend to meet this apparent madman or to remain where I was.

"Don't hesitate, Mr. Addison!" he cried, now beginning to recover his breath. "Do exactly as I tell you!"

"Good God!" I exclaimed.

I turned and ran to the door and on downstairs. For at last I had recognized the voice of this midnight runner. Throwing open the door, I held out my hand and the shabby-looking man extended his in return.

"Gatton!" I cried excitedly. "Gatton! What on earth does this mean? Why have you been masquerading in this fashion? I saw you here this morning and you never gave me the slightest sign of acknowledgment!"

"I never intended to!" panted the Inspector, staggering rather than walking up the stairs. "But I have performed one of the hardest tasks of my life to-night and have only succeeded by a few seconds!"

We were now at the door of my room, but:

"Don't go in!" said Gatton shortly. "Let me think what we must do."

"But I don't understand at all!"

"You will understand in a moment!" was the grim reply. "You would have understood already if you had lighted your candle."