assage can't begin at the end of either of these, and
been built up."

"I dunno, sir. Folk in the past as had to do with them passages did all
they could to make 'em cunning."

"But they couldn't have made a passage through the moat."

"Of course not, sir; it must have gone under it."

"Then it couldn't have started from here."

"Why not, sir?" said Ben, with a low laugh; "what's to prevent there
being another dungeon like this on the other side of the wall there, one
with a trap-door in it leading down ever so many steps into another
place, and the passage begin ten or twenty foot deeper."

"Something like the powder-magazine is made?"

"That's it, sir. We're in the lower part of a big round tower, and we
know there's those floors above us one on top of the other, and we don't
know that the old Roylands who built this place mayn't have dug down and
down before they started it, and made one, two, or three floors below
where we stand."

"What? Dug right down? Impossible!"

"They dug down that time as deep into the old stone to make the big
well, sir."

"Of course; then it is possible."

"Possible, sir? Oh yes; look at the secret passages there are in some
old walls, made just in the thickness, and doors leading into 'em just
where you wouldn't expect 'em to be. Up a chimney, perhaps, or a side
of a window. I heered tell of one as was quite a narrow door, just big
enough for a man to pass through, and you didn't walk into it, because
it wasn't upright; but you got into it by crawling through a square hole
with a thin stone door which fell back after you were through. Then you
stood up, and could go half round the old house it was in."

"Well," said Roy, "if there is such a passage, we must find it; but if
it has been built up, we might have to pull half the place down."

"Yes, sir; but first of all, we'll have a good look in these cellars,
for it mayn't have been built up, and we may find it easily enough.
Begin then, and let's try."

Ben trimmed the candle with his forefinger and thumb, making the flame
brighter, and then holding the light close to the flat face of the wall,
they examined stone after stone; but as far as they could make out, they
had not been tampered with since the day the masons concluded their
task.

Then the curved walls right and left were examined quickly, as they were
little likely to contain a concealed opening; lastly, the flags on the
floor, and, finally, Ben drew his