it was, the news that the gang was out of jail had caused the aged inventor some alarm.
It was not without some anxiety that Tom arose the next morning, fearing he would hear news that the bank had been broken into, but no such alarming report circulated in Shopton. In fact having made some inquiries that day of Ned, he learned that no trace had been seen of the mysterious men. The police had been on the look-out, but they had seen nothing of them.
"Maybe, after all, they weren't the same ones," suggested Ned, when he paid Tom another visit the next night.
"Well, of course it's possible that they weren't," admitted the young inventor. "I'd be very glad to think so. Even if they were, your encounter with them may have scared them off; and that would be a good thing."
The next two weeks were busy ones for Tom and Mr. Sharp. Aided occasionally by Mr. Swift, and with Garret Jackson, the engineer, to lend a hand whenever needed, the aeronaut and the owner of the speedy Arrow made considerable progress on their airship.
"What is your father so busy over?" asked Mr. Sharp one day, when the new aluminum gas holder was about completed.
"I don't know," answered Tom, with a some-
