man placed the things he carried in a closet partly filled with
rubbish. Then he flashed his light around carefully. Adam Adams got
down out of sight and placed his hand on the butt of his pistol. He
was resolved to take no more risks than were absolutely necessary.

Presently the light was lowered, and taking a peep Adam Adams saw the
man kneeling down and tugging away at an iron ring in the floor. Soon
a trapdoor came up, and the man, taking up his lantern, disappeared
from view, closing the trapdoor behind him.

The detective waited for several minutes and then stole forward in the
utter darkness. He had measured the distance perfectly and found the
iron ring with ease. He pulled upon it gently but firmly and raised
the secret door several inches.

A look below showed nothing but darkness. He strained his ears, and
heard a faint noise at a distance but could not determine whether it
was the flowing of the river over the stones or something else.

He got out his pistol and examined it with care, to make certain that
it was ready for use. Then, with a quick motion, he threw up the
trapdoor, dropped below, and closed the opening above him.

He felt as does a lion tamer stepping into a cage of beasts new to him.
He realized that he was on the verge of some important discovery, but
that this investigation might cost him his life.

He was on a narrow staircase. There were but ten steps and then he
found himself between two stone walls with the roof just above his
head. Not caring to take another drop into the unknown, he advanced
slowly, taking no step until he was sure of it.

Presently he came to a turn and then another. He could now see a light
shining ahead, coming from under a heavy wooden door. The barrier was
tightly closed. He tried it softly, to find it fastened on the other
side.

There was a strange whirr and a clicking in the apartment beyond, as if
some machinery was in motion. But then came a loud voice and the other
sounds stopped. By getting down on his hands and knees Adam Adams was
enabled to hear nearly all that was said in the place beyond the barred
door.

"I will listen to reports," said a voice which sounded much like that
of Matlock Styles. "Number One, have you performed the ghostly
manifestations?"

"I have, chief," was the answer.

"Did you notice anything unusual?"

"A boy and a girl on the other side of the river ran away as if the Old
Nick were after them."

"