"Don't you see?" persisted Hiram.
"See what?" asked Dave.
"A signal."
"You think so?"
"I surely do. Now, then, look sharp. There are figures about the fire. The fire is pitch or oil, or something that could be made to flame up quickly. One of the men threw something into it from a box. It was red fire."
"Why, yes," observed Dave slowly. "I'll admit that was some kind of a signal."
"For the airship," interrupted Hiram quickly. "Look, look again, Dave! One of the men is shading his eyes from the glare of the fire, and is looking straight up into the sky. Why, it's plain as day. They saw our airship when that searchlight caught us. They were waiting for an airship to come along."
"Another airship than ours, you mean?"
"That's it, and I'll bet the Drifter! They took ours for the Drifter. They want us to land. Why, see there, one of the fellows is looking through a field glass—as if he could make us out in the dark away up here!"
It did not take Dave long to drift to Hiram's way of thinking. The spot where the fire showed seemed to be a large yard of some kind, attached to a factory.