a gigantic
rabbit warren. I judged the cliffs to be natural in character, but in
the labyrinth of passages and rooms upon which one first entered, much
artificial work had been done. In places columns of brick upheld the
roof, and the walls had been trimmed and levelled by a tool. I
guessed--for it was a point upon which Dream could tell me nothing--that
the lords of Thule had at one time some intention of making use of these
natural excavations, and that they had been frightened from their task
by the absurd superstition which Dream had recounted to me. I could not
believe in the marvellous amphibious monster that had come out of the
sea, and for fifty years or more had lived in the heart of these cliffs.

I told Dream of my doubts, but she was not to be shaken. The track of
the animal when it went in had been clearly visible, and no track had
been found to show that it had gone out again.

"On what then does it live?" I asked.

"Things that it finds in the water."

"But you tell me that it has never gone back to the sea again."

"Never. But far within the caves--much farther than I have ever
gone--there is a great lake. It lives there. I will take you to a place
where you can hear the roar of the water falling into the lake. Follow
me closely or you may lose yourself."

She took me through many winding passages until she reached a point
where she knelt and put her ear to the ground. She made me do the same.
I could certainly hear the sound of running water below me, but that did
not prove the existence of the lake, much less of the monster that was
supposed to inhabit the lake. I told her this, and she did not like it.

"When you found me in the forest," she said, "I was very sad because I
had spoken to no one for many days, and I was to die and there was no
escape. Then because of your companionship and because you seem to hope
and to fear nothing, I became lifted up again. It is necessary for you
to think as I think, or I shall grow sad again. Therefore you must
believe in the great serpent."

"We will not speak of him. Show me where you sleep."

She took me by a passage that rapidly grew narrower until I could hardly
force my way into the chamber beyond. It was a simple sleeping-apartment
containing a bed of dried bracken and nothing more.

"Yes," she said, "I chose this place because the passage was so narrow
and the great serpent which was in the lake was so big. Here he could
not get to me."

"And