It was to drop news of captured, or dead, Allied airmen.

Then, as Tom, and the others watched, a little package was seen to
fall from the hovering aeroplane. It landed on the roof of one of
the hangars, bounced off and was picked up by an orderly, who
presented it to the commanding officer.

Quickly and eagerly it was opened. It contained some personal
belongings of Allied airmen who had been missing for the past week.
Some of them, the message from the German lines said, had been
killed by their falls after being shot down, and it was stated that
they had been decently buried. Others were wounded and in
hospitals.

"No word from Harry," said Tom, sadly, as the last of the relics
from the dead and the living were gone over.

"Well, I guess we may as well give him up," added Jack. "But we can
avenge him. That's all we have left, now."

"Yes," agreed Tom. "If we only--?"

A cry from some of those watching the German plane interrupted him.
The two air service boys looked up. Another small object was
falling. It landed with a thud, almost at the feet of Tom and Jack,
and the latter picked it up.

It was an aviator's glove; and as Jack held it up a note dropped
out. Quickly it was read, and the import of it was given to all in
a simultaneous shout of joy from Tom and Jack.