As soon as Lang sent the powerful engine into speed, racing down the runway into the wind, lifting the elevators to catch the propeller blast and tip upward the nose, then flying level, just above the ground for those essential few seconds in which flying speed was regained before the climb, Al opened the conversation.

“Lang,” he cried, pitching his voice to offset the noise about them, “did you know what they are saying about the accident?”

Langley nodded.

“This seems to be a test flight,” he said. “But I’m really flying over to the airport, in the city suburbs—Barney wants you along to scatter and pick up talk there.”

“What’s the airport got to do with the mystery?”

“Barney thinks that mysterious crate we saw in the field might have something to do with it,” Lang responded to Curt’s question.

“But Barney told us not to go building theories,” Bob objected.

“He’s older, and better able to see things clearly,” Lang reminded him. “So we will climb pretty high, as if for test dives and slips, and skids, and barrel rolls—you’d better be sure to snap your safety belts—not right now, though. This crate slips pretty sharp. But——”

“I think we’re wasting time,” declared Bob, “flying to the airport.”

“Why?” asked Lang.