d then, you can stop here. Stand on one side, Twining, and
you, Mrs. Barnes. Both of you stand on the bare floor near the wall."

Considerably surprised, Mrs. Barnes did as she was told, and uttered a
cry when she saw the floor begin to move. Jennings, who was pressing a
button at the end of the room, stopped. "Take her upstairs, Twining.
She will alarm the gang!"

"Alarm who?" cried the cook, struggling with the inspector. "Whatever
do you mean? Shame--shame to 'old a defenceless lady. 'Elp!"

But her cries for help were unheeded. Twining bore her up the stairs
and summoned one of his men. In a few minutes Mrs. Barnes was safely
locked up in her own bedroom in the cottage, a prey to terrors. Poor
woman, being innocent, she could not understand the meaning of this
midnight visit, nor indeed the mysterious moving of the floor. It had
never happened so before within her recollection.

Twining came down with six men, leaving the others to guard the exits
from the house and garden. At the door of the sitting-room he stopped
at the head of those he was bringing. At his feet yawned a gulf in
which steps appeared. The whole of the centre of the floor had
disappeared into the wall opposite to the fireplace, and the rough
steps led down into a kind of passage that ran in the direction of the
unfinished house. "This is the entrance," said Jennings, "it works
from a concealed button on the wall. Electricity is used. You see why
the sides of the floor are left bare; the carpet has quite disappeared.
But we have no time to lose," he jumped down lightly. "Come along men,
hurry up."

"As we will be at a disadvantage, we may as well get our barkers out,"
said the inspector, and the men produced revolvers. Then they went
into the burrow at the tail of the intrepid Jennings.

That gentleman stole along the narrow passage: It ran straightly for a
few yards and then took a turn to the right. The ground continued to
slope for some distance until it terminated in a heavy door of wood.
Jennings fancied this might be locked, and felt a pang of
disappointment. But it proved to be merely closed to. Apparently the
coiners were so sure of their safety that they did not trouble to keep
the door locked. The detective opened it gently, and with the men
close at his heels stole forward. He held his revolver lightly in his
right hand, ready for emergencies. The passage was quite dark, but
being narrow, the men had no hesitati