Boris. Until he knew more of
the lay of the land, he could not even make a real plan, but it was
possible, he thought, that something that was in his mind might easily
prove to be feasible.

It was easy, with his torch and the guiding arrows, to follow the
devious, winding course of the passage. He surmised that its ascents and
descents, which seemed arbitrary and unreasonable as he pursued them,
were due to other entrances than the one he knew. It would be necessary,
as he could understand, to have more than one means of getting in and
out of such a passage. And when he found himself at last going in a
straight path which sloped easily downward, he guessed that he was
beyond the house, and that he had come to a part of the passage that led
to the outer world.

Here there was a trace of dampness, but nothing like what might have
been expected in what was really a tunnel. Fred had to admire the
excellence of the construction work. The descent, as he knew from what
he had seen outside, must really be very sharp. But it was managed here
with turns and zigzags so that the grade was never very sharp.

Fred became suddenly conscious of a change in the air.

"I must be near the opening," he thought.

A couple of minutes proved that he was right. He now remembered that
Boris had not had time to tell him how the door or gate was operated.
But he decided not to go back at once, but to try to discover the secret
for himself. It had occurred to him that it was more than probable that
a sentry or two might be left in the house, and he had no mind to stay
in the passageway, helpless and useless, if Vladimir found it impossible
to let him out at once.

At the end of the passage he found a solid, seamless door. He decided at
once it must work on an axis of some sort and that it must be set in
motion by pressing a spring. And so, steadily and systematically, he
searched the whole door, until he struck the right spot at last. As the
door moved, he marked the spot with a tiny pencil mark. It swung
open--and he looked into the eyes of a startled German soldier, his
mouth wide open!

CHAPTER VII

A DARING RUSE

It would be hard to say which was more surprised--Fred or the soldier.
For just a moment they stood, both of them, perfectly still, staring at
one another with fallen jaws. And then Fred acted by pure instinct, and
without the semblance of a plan in his mind. He had played football in
school and on the team of hi