ll 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.

"Nothing, I trust, has happened?"

"Nothing whatever, Sir Walter. No sign or sound of anything out of the
common can be recorded."

"Thank Heaven--thank Heaven for that!"

"Though we had exhausted the possibilities of such a thing, we none
the less expected gas," explained the detective. "That seemed the
only conceivable means by which life might be destroyed in that room.
Therefore we wore gas masks of the latest pattern, supposed to defy any
gaseous combination ever turned out of a laboratory. It is well known
that new, destructive gases were discovered just before the end of the
war--gases said to be infinitely more speedy and deadly than any that
were employed. As to that, and whether the Government has the secret
of them, I cannot say. But no gas was liberated in the Grey Room last
night. Otherwise a rat in a trap and birds in a cage, which we kept by
us, would have felt it. The room is pure enough."

Sir Walter followed him down the corridor, and chatted with the other
men also. They had left the Grey Room and taken off their masks; they
looked weary and haggard in the waxing, white light of day.

"You've done your duty, and I am beyond measure thankful that no evil
has overtaken you. What can now be prepared for you in the way of food?"

They thanked him, and declared that in an hour they would be glad of
breakfast. Then Sir Walter went to his own apartments, rang, and gave
the needful directions. He joined Mary soon afterwards, and she shared
his thanksgivings. She was already dressed, and descended immediately to
Dr. Mannering.

Henry Lennox also appeared soon afterwards. He had already learned from
Fred Caunter that the watchers were safely through the night.

Chadlands was the scene of another inquest, and again a c