a chill ran through her. She felt a dull sense of foreboding. But the
next minute she shook it off. After all, why shouldn't Mr. Harding and
Mortlake be driving to the farm? Mr. Harding's financial dealings
comprised mortgages in every part of the island. It was quite probable
that the farmer was in some way involved in the old man's nets. Possibly
that was the reason of all that money being stored in the wall safe.

Refusing courteously an invitation extended by Miss Prescott to spend the
night at the homestead, Lieut. Bradbury was driven to the station by Roy,
after they had dropped Peggy, and just managed to make a New York train.

"I shall be back to-morrow," he said, "and have a look at Mortlake's
machines. Of course, the government wants to give everybody a fair field
and no favors."

"Oh, of course," assented Roy, pondering in his own mind what sort of a
machine this mysterious Mortlake craft was.

Suddenly there flashed across his mind a thought that had not occurred to
him hitherto. The _Golden Butterfly_ had been left under the shed at the
farm. What was there to prevent Harding and Mortlake from examining it and
acquainting themselves with the intricacies of the self-starting mechanism
and the automatic balancing device?

There was no question that the farm must have been their destination. Roy
blamed himself bitterly for not foreseeing this. He had half a mind to
return to the farm and bring the aeroplane home himself. But it was
growing dark, and a distant rumble seemed to presage the return of the
afternoon's storm.