o a cloud of dust, for Dean had started up the motorcycle
before he finished speaking and already was speeding away.

"Where now?" asked Jane.

"I don't know," he answered frankly, "I only know we are going the
direction the Hoffs went, and I want to gain on them before they get too
far ahead. The chap back there had told us all he knew and was beginning
to get curious, so I thought it better to vamoose."

"It's funny about his never seeing them coming back."

"Probably there is nothing mysterious about that. I have a notion they
always come up one side the river and down the other, taking the 125th
Street ferry home. That would not be a bad plan to help them in eluding
too curious observers. All these German spies are trained to leave as
blind a trail behind them as possible. The thing we have got to discover
is what brought them up here. We've just got to find out their
destination."

"I am afraid there is little chance of our doing that," insisted Jane.
"We've nothing to go on."

"We've learned something. We know that their destination is somewhere
between here and Fort Lee on this side of the river. That narrows down
the search considerably. That's more, too, than anybody else that the
Chief has had on their trail has learned. Something tells me that we are
getting warm right now. Obviously the place they come to must be nearer
West Point than it is New York. They would hardly take too roundabout a
course, even for the sake of hiding their tracks. Keep a sharp lookout
for tire tracks leaving the main road."

The route they were following quickly led them into a sparsely inhabited
mountainous district and instead of the concreted state highway they
found themselves on a hilly dirt road, full of ruts and loose stones
that made travel difficult. At times it was all Dean could do to manage
the machine, so that he had to leave most of the task of observing the
by-ways to Jane. For more than two miles they had seen neither house nor
barn. Once or twice they came upon little used lanes leading off through
the woods, but none of them showed any traces of the recent passing of
an automobile.

As they came dashing around a curve on a steep down-grade, where hardly
more than the semblance of a road had been cut into the hillside, Jane
caught her breath sharply. Above the roar of their own motor she thought
she heard some other noise, something that sounded like another car
near-by; yet neither behind nor ahead was the