“And here it is, some of it!” Goggles was getting excited. “Let’s have a look at this other bag.” He dumped coarse dirt on a second paper. “Came from the bottom of those shoes,” he explained. “Yes, there it is—red sand, some oil mixed in—just what you’d find on a landing field. They’re the men all right.”
“Well, that’s something,” Johnny replied quietly.
“What are we going to do about it?” Goggles asked.
“Nothing just now. You can’t keep people from flying over your head.”
“But you’d think—Say!” Goggles’ tone changed. “There’s some sort of chemical in this dust from the sweeper. Two kinds. One’s coarse and gray. Other’s a fine white powder.
“Yes.” He examined the contents of a small envelope. “Some of the white powder is in the dust I took from the pocket of an old coat they left. Must have rubbed it off his hands into his pocket. People do that without thinking.”
“Goggles—” Johnny found it hard to control his voice, “could you make a bright light by touching off two powders?”
“I’ll say you could! All kinds of light.”
“Goggles—” Johnny’s tone was deeply serious, “you separate those chemicals from the rest of the dust as well as you can, then keep them—both kinds. It—it may be important.”
“I’ll do more than that,” Goggles agreed. “I’ll take them down to the laboratories. I’ll ask someone to test ’em out and tell me what they are. Maybe I’ll ask the ‘Prince.’”