you. Take to the tunnel without hesitation
if there is an attack upon the house, or a search. I think you will be
safe as long as you are watchful, but you cannot be off your guard for
even a moment. The Germans will think that you went back with the
Cossacks but they will try to make sure."

"We will be careful," said Boris. "You are sure of what you have
learned? There will be no more than two army corps in this region?"

"That is certain. I have scouted for twenty miles to the west and I have
been along the railway lines. If there were more troops coming, I
should have discovered it. I am sure of that."

"And now you are going back toward our lines?"

"Yes. I may be of service to your father. And, in any case, I shall be
of more use if I am with the German advanced position than if I stayed
here, far in the rear. Good-bye!"

He departed through the tunnel. And then for Fred and Boris began a task
almost harder than any that could have been set. They had to wait. There
was nothing for them to do except sit in the little turret room. Below,
Vladimir and the others kept a sort of guard, but there seemed little
reason even for that.

From the turret, whence the wireless waves were sent pulsing out through
the air, a fine view of the surrounding country for a good many miles
was to be had. For the most part this was a level section, slightly
undulating, but with very few high spots. From their vantage point the
roads stretched out like ribbons or like lines on a map. Fred opened the
wireless and amused himself by listening. At first he could hear only a
confused jumble through the receivers that were clamped to his ear. Then
he changed his wave length, experimenting until he got a clear series of
dots and dashes.

"I think I'll take this down," he said to Boris. "It'll be like Greek to
us, of course, but it's all German wireless talk, and it all means
something. Perhaps if we're lucky, we'll stumble on to the key of the
code they're using, and that might be useful."

After a time Boris, who could receive well enough but was an inexpert
sender, relieved him, and Fred, taking the field glass, began to search
the horizon. Soon something caught his eye and held his attention. At
first he thought he saw troops moving, coming from the east. It seemed
strange that German troops should be in retreat so soon, but in a moment
he understood. He did not see soldiers moving along the road, but a
company of civilians, with car