"I don't know," and Mary seemed a bit put out by this
simple question. "What do you mean by his tricks?" she
asked, and a close observer might have thought she was
anxious to get away from the subject of Tom's enlistment.

"Oh, like that one when he sent you something in a box
labeled 'dynamite,' and gave us all a scare. You can't tell
what Tom Swift is going to do next. He's up to something
now, I'll wager, and I don't believe any good will come of
it"

"You didn't think so after he sent his wireless message,
and saved us from Earthquake Island," said Mary, smiling.

"Hum! Well, that was different," snapped Mr. Nestor. "This
time I'm sure he's up to some nonsense! The idea of crashing
down a fence! Why doesn't he enlist like the other chaps, or
sell Liberty Bonds like Ned Newton?" and Mr. Nestor looked
sharply at his daughter. "Ned gave up a big salary as the
Swifts financial man--a place he had held for a year--to go
back to the bank for less, just so he could help the
Government in the financial end of this war. Is Tom doing as
much for his country?"

"I'm sure I don't know," answered Mary; and soon after,
with averted face, she left the room.

"Hum! Queer goings on," mused Mr. Nestor. "Tom Swift may
be all right, but he's got an unbalanced streak in him that