. "Look!-- They're all
alike, with red backs and mottled sides." She opened one curiously.
"Why!--they're called 'Punch'! What a strange name! What kind of books
can they be?" And then, on further examination,--"Oh! I see. It's a
collection of English papers full of jokes and politics and that sort
of thing. And this one is from way back in 1850 Why, Cynthia, these are
the most _interesting_ things!--"

But Cynthia had already extracted another volume and was absorbed in it,
chuckling softly over the old-time humor. Joyce grouped the five candles
on the floor and they sat down beside them, from time to time pulling
out fresh volumes, reading aloud clever jokes to each other, and
enjoying themselves immensely, utterly unconscious of the passing
moments.

At length they found they had skimmed through all the volumes of
"Punch," the last of which was dated 1860, and had them piled up on the
floor beside them. This left a long space on the shelf from which they
came, and the methodical Cynthia presently rose to put them back. As she
fitted in the first volume, her eye was suddenly caught by something
back of the shelves, illuminated in the flickering candle-light.

"Joyce, come here!" she called in a voice of suppressed excitement. And
Joyce, who had wandered to another corner, came over in a hurry.

"What is it?"

"Look in there!" Joyce snatched a candle and held it close to the
opening made by the books. Then she gave a long, low whistle.

"What do you make of it?" demanded Cynthia.

"Just what it is! And that's as 'plain as a pikestaff'--a _keyhole_!"
Cynthia nodded.

"Yes, but what a strange place for it--back of those shelves!--" They
brought another candle and examined the wall back of the shelves more
carefully. There was certainly a keyhole--a rather small one--and around
it what appeared to be the paneling of a door, only partially visible
through the shreds of old, torn wall-paper that had once covered it.

"I have it!" cried Joyce, at length. "At least, I think this may be an
explanation. That's a small door, without a doubt,--perhaps to some
unused closet. Maybe there was a time, when this house was new, when
this room wasn't a library. Then somebody wanted to make it into a
library, and fill all this side of the room with book-shelves. But that
door was in the way. So they had it all papered over, and just put the
shelves in front of it, as though it had never been there. You see the
paper has fallen