"What?" asked Jack.
Before answering, Fred again put the receivers over his own ears. The call still was being repeated.
"Our call," he informed them brusquely. "R-S-7—and there's no doubt that it's being sent out by that other plane. Shall I answer?"
"Not under any circumstance," Jack commanded, for the first time really exerting his prerogative as captain of the crew.
"They're saying something," interjected Fred, grabbing pencil and pad and beginning to write rapidly.
A moment later he laid aside the receivers and picked up the paper to read aloud. "Listen to this," he said. "Here's what I caught: 'R-S-7. If you can catch this, reply immediately. Mistake been made. Return at once.'"
"Who signs it?" Jack asked.
"No signature at all; they just kept repeating that message," said Fred.
"Well, let 'em keep on repeating it," Jack snapped out. "Poor idiots! They might know that scheme wouldn't work. They just want to get a line on where we are. If Bronson or anybody in authority wanted to reach us it would come in our code. It shows, though, that those fellows are determined to reach us for a mix-up if they can."