e of the aeroplane, was the first to see the
ground below.

"Land below!" he called to Hal.

"Anything in sight?" asked Hal.

"Not a thing. Coast seems to be perfectly clear. Trees near, too; so we
can hide the plane, if you go almost straight down."

Hal followed directions and a moment later the biplane came to rest upon
the ground as lightly as a bird.

Hal, Chester and Stubbs climbed out quickly.

"Guess we had better run the machine back among the trees," said Hal.
"Lend me a hand here."

It was the work of but a few moments. Hal walked some distance away and
surveyed the spot where the machine had been rolled. He walked around it
on all sides.

"O.K.," he said. "You wouldn't know it was there unless you happened to
be looking for it."

"Well, what now?" asked Chester.

"Guess we had better don those German uniforms and prowl about a bit."

"Snoop, eh," said Stubbs.

"Now look here, Stubbs," said Hal, "you just keep quiet and get into this
uniform we brought along for you."

Mumbling to himself, Stubbs obeyed.

Arrayed in the German uniforms--the attire of lieutenants--the three
advanced toward where they felt sure the main German entrenchments must
be. Hal glanced at his watch in the moonlight.

"Ten o'clock," he said. "Within three hours we should have learned all we
need to. As soon as we reach the German lines we shall separate. We'll
meet here again at two o'clock. Is that satisfactory?"

"Suits me," said Chester.

"Want to lose me, do you?" grumbled Stubbs. "Never mind, though. I'll be
here by the time you are."

"Pick up every scrap of information possible," Hal enjoined his
companions. "Don't take the trouble to write it down. Just impress it on
your memory."

The others nodded their understanding.

The three came now upon a light in the distance.

"Germans ahead, I guess," Chester whispered. "Careful and let all further
conversation be in German."

The lad was right. Advancing two hundred yards farther, the three friends
came upon the outlying sections of the big German camp. Sentinels moved
about in the darkness, their forms lighted up now and then by the flare
of campfires--for the night was very cold.

Once they were challenged by a sentry, but when the man looked at their
uniforms in the moonlight, he lowered his rifle and passed on.

"I'll go straight ahead," said Chester in a low voice. "Hal, you go north
and let Stubbs go south."

And thus it was arranged without fu