rious airship!" exclaimed the odd
man. "That was why the aeroplane moved about over your place. Those in
it hoped that the fire would not break out until you were all asleep,
and that the shed and the Humming-Bird would be destroyed before you
came to the rescue. Some of your enemies are still after you, Tom."

"And it was Andy Foger, I'll wager!" he cried. "He was in that
aircraft! Oh, I'll have a long score to settle with him!"

"Of course you can't be sure it was he," said Mr. Damon, "but I
wouldn't be a bit surprised but what it was. Andy is capable of such a
thing. He wanted to prevent you from taking part in the race."

"Well, he sha'n't!" cried Tom, and then he thought of his invalid
father. They made a further examination of the shed, and discovered
another empty bomb. Then Tom recalled having seen something drop from
the mysterious aeroplane as it passed over the shed.

"It was these bombs," he said. "We certainly had a narrow escape! Oh,
wait until I settle my score with Andy Foger!"

As there would be but little use for the aeroplane shed now, if Tom
sent his craft off to the meet, it was decided to repair it temporarily
only, until he returned.

Accordingly, a big tarpaulin was fastened over the hole in the roof.
Then Tom put a new wing tip on in place of the one that had been
scorched. He looked all over his sky racer, and decided that it was in
fit condition for the coming meet.

"I'll begin to take it apart for shipment, as soon as I hear from the
specialist that dad is well enough for me to go," he said.

It was a few hours after the discovery of the empty bomb that Tom saw
Dr. Gladby coming along. The physician was urging his horse to top
speed. Tom felt a vague fear in his heart.

"I've got a message from Dr. Hendrix, Tom," he said, as he stopped his
carriage, and approached the lad.

"When can he come?" asked the young inventor, eagerly.

"He can't get here, Tom."

"Can't get here! Why not?"

"Because the railroad bridge has collapsed, and there is no way to
come. He can't make any other connections to get here in time--in time
to do your father any good, Tom. He has just sent me a telegram to that
effect. Dr. Hendrix can't get here, and..." Dr. Gladby paused.

"Do you mean that my father may die if the operation is not performed?"
asked Tom, in a low voice.

"Yes," was the answer.

"But can't Dr. Hendrix drive here in an auto?" asked the lad. "Surely
there must be some way of g