air. They had been so confident that
the passage would surely be taking them to the outer world; to find
themselves once more at a full stop was a terrible blow.

"Must we go all that dreadful long way back?" wailed Cicely.

"I expect there is some door that we've passed without knowing it,"
replied Lindsay, rather chokily.

"Then we can never find it in the dark. It's no use. We shall both
starve to death here, and they'll discover our skeletons a hundred years
afterwards."

Cicely had utterly broken down, and was sobbing bitterly.

"We won't give up too soon," said Lindsay, whose sturdy courage stood
her in good stead on this occasion.

She had been feeling about here and there on the blank wall that faced
them, and her fingers at last encountered something that seemed like a
sliding bolt. She pushed it back eagerly. A door opened outwards,
letting in a blaze of light. To their utter amazement they were gazing
down into the picture gallery!

It did not take them many seconds to spring to the floor and turn round
to look through what aperture they had made their escape. It was the
portrait of Monica Courtenay that formed the secret exit. It had swung
out, frame and all, into the gallery, and appeared to be fitted with
hinges so as to close and unclose quite easily.

"Now I see why the picture shook in its frame that day!" exclaimed
Cicely. "I wonder we never thought of this before."

"And of course that was why she was supposed to guard the fortunes of
the Courtenays. No doubt they always kept their valuables in this
hiding-place, and only the head of the family would know the way to it."

"So old sayings do generally mean something, and aren't just nonsense."

"Let us go and tell at once. Everybody'll be wondering where we are.
They must be doing prep. now, and Miss Russell will be sitting with the
first class."

The headmistress's tranquil demeanour was not usually easily ruffled,
but she sprang up in excitement as her two missing pupils burst into the
library proclaiming the glorious news.

"Lindsay and Cicely! Where have you been? I was growing most uneasy at
your absence. You say you have actually found Sir Giles's treasure? It
is hardly to be credited. Girls, girls, try to calm yourselves and give
me an intelligible account!" as first one and then the other took up the
tale in disjointed sentences.

"We played hide-and-seek--and fell through the bottom of the
settle--there were great bags of gold