“Do.  You will find all you need in the dining-room.  I directed Masters to leave ample there, in case the detectives might want food.”

“Shall I bring you something—­a whisky, and a biscuit?”

“No, no.  I need nothing.”

The doctor went his way, and passed an hour with meat and drink.  Then he felt an overpowering desire to sleep, but resisted it, lighted his pipe again, and, resumed his march in the hall.  He listened presently at the library door, and was gratified to hear a gentle but steady snore.  The sound pleased Mannering well.

He padded about once more, resolved to keep awake until the vigil was ended.  Then he would go to bed and sleep.  It was now past three o’clock on a still, winter night—­a lull and interval between yesterday’s storm and rough weather yet to come.  The doctor went out of doors for a time and tramped the terrace.  A waning moon had risen, and the night was mild and cloudy.

Bright light shot out like fans into the murk from the east and south windows of the Grey Room.  Returning to the house, the watcher listened at the foot of the staircase, and heard the mumble of men’s voices and the sound of feet.  They were changing the guard, and the detective in the corridor gave up his place to one from inside.  All was well so far.

Then Mannering went to the billiard-room, lolled on the settee for a time, and drowsed through another hour.  For a few minutes he lost consciousness, started up to blame his weakness, and looked at his watch.  But he had only slumbered for five minutes.

At six o’clock he told himself that it was morning, and went in again to Sir Walter.  The old man had wakened, and was sitting in quiet reflection until daylight should outline the great window above the dead.

“The night has been one of peace,” he declared.  “The spirit of poor May seemed near me, and I felt, too, as though his son were not far off, either.  Is all well with the watchers?”

“I leave you to inquire, but don’t go too near them.  Night fades over the woods, so the day can be said to have begun.”

“Doubtless the household will be stirring.  I shall go and inquire, if they will permit me to do so.  Oblige me by staying here a few minutes until I call my daughter.  I do not want our poor friend to be alone until he leaves us.”

“I will stay here for the present.  But don’t let Mary be called if she is sleeping, and turn in yourself for a few hours now.”

“I have slept off and on.”

Sir Walter left him and ascended to the corridor.  Already light moved wanly in the windows.

He stood at the top of the staircase and raised his voice.

“Is all well, gentlemen?” he asked loudly; but he received no answer.

“Is all well?” he cried again.

And then from the gloom emerged Inspector Frith.  He had doffed his gas mask.

Sir Walter switched on an electric light.