"We'll try to be careful," answered Dick, with a grim smile. "We don't
want a tumble if we can help it."

"It is a grand sport," answered the head of the college. "Before long
I expect to see aeroplanes in constant use."

"Wouldn't you like to go up with us some day, Doctor?" questioned Tom,
slyly.

"Well-- er-- perhaps, Thomas. But not just yet. I wish-- er-- to see
them more in general use first." And then the doctor bowed the
students out.

The boys lost no time in preparing for the trip to Plankville. After a
somewhat hasty lunch they put on their flying suits and then went down
to where the Dartaway was housed, in one of the buildings attached to
the gymnasium.

"Looks to be all right," remarked Dick, after an inspection of the
flying machine, and while Sam and Tom were filling the gasoline tank
and the oil distributor.

The engine was tried out for a minute, and found to be in perfect
order. As usual, as soon as the explosions of the motor were heard, a
crowd commenced to gather, to see the start of the flight.

"Wish you luck!" cried Stanley.

"Say, look out that you don't forget how to stop and sail to the North
Pole!" sang out Spud Jackson.