The Hardy boys grinned as they saw Chet step out into the road and swing himself lightly up on the back of the wagon. Mr. Billers was bringing some supplies back to the farm and Chet was hidden from view by a bag of flour.

As the wagon rumbled past, Chet sounded the automobile horn.

It shrieked sharply and insistently.

Mr. Billers, being a lazy man, did not even look behind. He simply tugged lightly at the reins and the horses edged over to the side of the road.