iece.
See, here are the joints; I can feel them with my fingernail, though I
can scarce see them with my eyes. Let us count the number of the stones
used. Yes; there are nine in all from top to bottom, each of the same
width. Therefore the seventh from the top is the third counting from the
bottom. This is the stone which is the key."

So saying, Gaston set his knee against it and pressed with all his
might. Almost to his own surprise he felt it give as he did so, and
Raymond uttered a short cry of astonishment: for the whole of what had
looked like a solid wall revolved slowly inwards, revealing a
continuation of the passage which they had been traversing so long, only
that now the passage was plainly one in the interior of the house; for
the walls were of masonry, and the dimensions were far more regular.

"This is the secret door," said Gaston exultingly. "It is in truth a
cunning contrivance. Let me have the light here a moment, Brother. I
will see what the trick of the door upon this side is."

This point was quickly settled by an inspection of the ingenious
contrivance, which was one purely of balance, and not dependent either
upon springs or bolts. Probably it dated back from days when these
latter things were hardly known, and was so satisfactory in the working
that it had never been improved upon.

"The way to Basildene is always open to us," murmured Raymond, with a
quick thrill of exultation, as the brothers passed through the doorway
and let it close behind them; and then they forgot all else in the
excitement of the search after the woodman's miserable son.

What strange places they came upon in this underground region below the
ill-famed house! Plainly these cells had been built once for prisoners;
for there were fragments of rusty chains still fastened to the stone
floors, and in one spot a grinning skull lying broken in a corner sent
thrills of horror through the brothers' hearts. From time to time the
sound of that unearthly wailing reached their ears, though it was almost
impossible to divine from what direction it proceeded; and it had a far
less human sound now that the boys were within the precincts of the
house than had been the case when they were still outside.

Whether this was more alarming or less they hardly knew. Everything was
so strange and dreamlike that they could not tell whether or not all
were real. They pressed on eager to accomplish the object of their
search, resolved to do t