were resorting to
dodging tactics, in an endeavor to escape. Now they would shoot
upward, and again toward the earth, varying the performance by
steering to the right or left. Ned had constantly to shift the light
to keep them in focus, so that Mr. Damon could see where to steer,
but, with all this handicap, the eccentric man did very well, and he
was never far out in his judgment.

"By Jove!" suddenly murmured Tom, as he tried once more in vain to
open a clogged valve. "I'm afraid we can't do it. Koku, lend a hand
here!" he exclaimed as the giant entered. "See if you can twist this
wrench around, but don't break off the handle, whatever you do."

"Me shove," replied the giant simply, as he grasped the big wrench.

Once more Ned glanced at the pressure gage. It showed seven hundred
pounds now, and there was only a margin of safety of one hundred
pounds more, ere a terrific explosion would occur. Still Tom had not
given the order to descend to earth.

"Are you going to make it, Tom?" asked the government agent,
anxiously, as he stood over the young inventor.

"I--I think so," panted Tom. "Are we near the Dominion line,"

"Pretty close," was the discouraging answer. "I'm afraid we can't
get 'em before they cross. Can you use any more speed?"

"I don't know. Ned, see if you can get another notch out of her."

With one hand Ned reached for the accelerator lever on the wall near
him, and pulled it to the last notch. The Falcon shot ahead with
increased speed, but, at the same instant there came a gasp from
Koku, and the sound of something breaking.

"There! He's done it!" cried Tom in despair. "I was afraid you'd be
too strong for that wrench, Koku. You've broken off the handle. Now
we'll never be able to loosen that valve."

Ned gave one more glance at the pressure gage. It showed seven
hundred and fifty pounds, and the needle was slowly moving onward.

"Hadn't we better descend," asked Mr. Whitford in a low voice.

"I--I guess so," answered Tom, despairingly. "Where are we?"

Ned flashed the light downward for an instant.

"Just crossing over the St. Regis Indian reservation again," he
replied. "We'll be in Canada in a few minutes more."

"Where are the smugglers?"

"Still ahead, and they're bearing off to the right."

"Going toward Montford," commented the government man. "We've lost
'em for to-night, anyhow, but they didn't get their goods landed, at
any rate."

"Send her down, Ned!" exclaimed Tom,