As he ran he kept his eyes upon the low building beyond. In this manner
he plainly saw the stooping figure of a man or boy making off in a
roundabout way so as to avoid him.

Frank's heart was burning with indignation because of this dastardly
attempt to ruin the gallant little airship that had so nobly stood all
tests and proven itself a splendid piece of workmanship.

"Oh, the contemptible coward! I'd just like to chase after him and get
my hands on him once!" was the thought that passed through his brain.

But he knew he could not. The scoundrel, no matter who it was, must be
allowed to escape in order that he turn his attention to the burning
shed and try to save the airship from destruction. Once the fire got
inside, there was enough of the dangerous gasoline about to insure the
speedy burning of the whole flimsy fabric, all but the motor itself.

So Frank kept headed straight for the hangar, trying to shut out the
sight of that crouching, fleeing figure. He continued to lift his sturdy
young voice in repeated shouts:

"Fire! Fire!"

Those in the house must hear; yes, and the neighbors, too. He might not
be able to master the flames alone and single handed, and would need
help. Besides, it was only right that Andy, being part owner in the
monoplane, should be made aware of its sudden peril.

As he thus drew near the low building he saw that the fire had already