“By questioning filling station attendants, we may be able to learn which way it went from the crossroads,” she urged.

“Come on, then,” said Salt.

Joe, faithful as ever, waited in his cab outside the mansion. Penny chose to ride beside him, as the front seat offered an unobstructed view of the road.

The cab turned away from the mansion and swept down the familiar twisting highway. At the first bend, the bright headlights illuminated a patch of snow along the ditch. Penny thought she saw a small, dark object lying on the ground.

“Stop the car!” she cried.

Joe brought the cab to a standstill a little farther down the road.

Penny leaped out and ran back to the ditch. Lying just at its edge was a leather portfolio. A glance satisfied her that it had belonged to her father.

“Salt! Louise!” she shouted. “I’ve found Dad’s satchel!”

The others came running. By that time Penny had examined the portfolio. It was empty.

“Just as I thought,” she muttered. “Those men were after the evidence Dad carried! And they got it, too!”