in the course of their adventures in the Boarded-up House, they found
themselves before an insurmountable barrier.

The door was locked!

CHAPTER V

JOYCE MAKES A NEW DISCOVERY. SO DOES GOLIATH

Yes, the door was locked, and there was no vestige of a key. Joyce was
suddenly inspired with an idea.

"Let's try the keys of the other doors! I noticed that they most all had
keys in the locks. Perhaps one will fit this." They hunted up several
and worked with them all, but not one made the slightest impression on
this obstinate lock.

"Now isn't this provoking!" exclaimed Joyce. "The only room in the house
that we can't get in, and the most interesting of all, I'm certain! What
_shall_ we do?" Cynthia made no reply, but looked at her little silver
watch.

"Do you know that it's quarter-past six?" she asked quietly.

"Mercy, no! We've got to go at once then. How the time has gone!"
Reluctantly enough they hunted up Goliath, who in thorough boredom had
returned to his place on the hearth-rug in the big bedroom, gathered
together their candles, and found their way to the cellar. Cynthia had
thoughtfully requested a tin biscuit-box from the grocer, and in this
they packed their candles, thus protecting them against the ravages of
mice, and left them in the cellar near the window. Then they clambered
out.

"To-morrow's Saturday," said Joyce. "In the morning we'll go to the
library and look up that book of costumes. After lunch we'll go back to
the B. U. H. and finish exploring. There's the attic yet, and maybe we
can find that key, too!" With a gay good-by they separated each to her
home, on opposite sides of the Boarded-up House.

The result of their researches in the library, next morning, was not
wholly satisfactory. They found that the most recent fashion of
hoop-skirts or crinolines had prevailed all the way from 1840 to 1870,
or thereabouts. And while these dates limited, to a certain extent the
time of the mysterious happening, it did not help them very much. They
felt that they must look for some more definite clue.

That afternoon they entered the Boarded-up House for the third time.
They found Goliath already in the cellar, owing, no doubt, to the fact
that Bates's pup was patrolling the front yard. So they invited him to
accompany them, an invitation which he accepted with arched back and
resounding purr. Deciding to explore the attic first, they found that a
door from the upper hall opened on a st