"Haven't time to tell you now," flung back the running lad over his
shoulder. "I've got to catch Andy! Then I'll explain. He's trying to
get ahead of us. I guess, but we'll stop him!" Thereupon Tom flung
himself against the door of the airship shed. The young inventor
found the portal bolted, though it vibrated with the impact of his
body.

"Come out of there, Andy Foger!" cried Tom, pounding on the door.
"Come out, or I'll get an officer, and have you arrested!"

There was no answer.

"Come out, I say!" repeated Tom.

"Around th' back! Try th' back door!" suggested the miner, who had
hastened to Tom's side. "Maybe he's run out that way!"

Tom listened. There was no movement in the shop. Then the young
inventor sprinted around the side. He was just in time to see the
bully running away over the lots and fields in the rear of his
father's premises. Andy had climbed out of the back window of the
shed, into which Tom and Ned had peered that day, had climbed the
high fence, dropped down on the other side, and was now running away
with all the speed he could muster.

"Come back--!" began Tom, and then he realized that his enemy could
not hear him. The bully was too far away. At the same time our hero
realized that it would be useless to give chase, for Andy had too
much of a start. There was nothing to do but to turn back, and Tom
knew that his delay in trying to gain an entrance at the front door
had given Andy the very opportunity he needed to escape at the rear.

"Well, this is a bad turn of affairs," remarked the lad, as he faced
the puzzled miner.

"What is, Tom?"

"Him having that map. It shows the location of the valley of gold,
doesn't it, and tells how to get there?"

"That's what it does!"

"How did Andy happen to get it?"

"Jest as I told you. I was on my way t' your house, havin' inquired
at th' post-office, an' the man said that at your place there was a
big shed, where you kept your airships. I come along, an', of
course, when I see this house, an' the shed, an' had a glimpse of
th' airship, I, of course, thought it was your place. An', though
you'd never told me about it, I thought maybe this lad was in
business with you. So, like a blamed young tenderfoot, I blurted out
my business afore I thought, an' handed him the map for safe
keepin'. He took it, too, that's the worst of it."

"Yes, that's the worst of it," agreed Tom, "But I'll get it back, if
I have to cause his arrest, and search h