"Must have come to one side," he reasoned "I want to get to the front. Then, maybe, I can see a sign that will tell me what I want to know."
The lad turned to the left, and, presently came to another parapet. It was higher, and ornamented with terra-cotta bricks. This, evidently, was the front. As Tom peered over the edge of the little raised ledge, there flashed out below him hundreds of electric lights. The city illuminating plant was being repaired. Then Tom saw flashing below him one of those large signs made of incandescent lights. It was in front of the building, and as soon as our hero saw the words he knew where the airship had landed. For what he read, as he leaned over, was this:
MIDDLEVILLE ARCADE
Tom gave a cry.
"What's the matter?" called Mr. Sharp.
"I've discovered something," answered Tom, hurrying up to his friend. "We're on top of the Middleville Arcade building."
"What does that mean?"
"It means that we're not so very far from home, and in the midst of a fairly large city. But it means more than that."
"What?" demanded the balloonist, struck by
