Michaelson came to the bridge and listened quietly to what Higgins had to say. His grave face registered no emotion but his eyes were grim.
"I can definitely tell you two things," he said at last. "One of them is that we are not in what could be called the future."
"But those two planes were better than anything we have invented!" Captain Higgins insisted. "The airplane was not invented until 1907. This has to be the future."
"Men invented airplanes in 1907," Michaelson said. Ever so slightly he emphasized the word "men."
Higgins stared at him. Slowly, as he realized the implication of what the scientist had said, his face began to change. "What are you driving at?" he said, his voice a whisper.
Michaelson spread his hands in a helpless gesture. "The Wright brothers invented the lighter-than-air ship early in the twentieth century," he said. "They were the first men to fly a plane, the first men of our race. But how do we know what happened on earth a million years ago, and I can definitely tell you that we are at least a million years in the past? The history that we know fairly well does not cover a span of more than five thousand years. How can we be certain what happened or did not happen on earth millions of years ago?"
The scientist spoke quietly, his voice almost a whisper. "We are before the time of the airplane. Yet we find airplanes? What do you think that might mean?"
"I—" Higgins faltered, his mind flinching away from facing the unknown gulfs of time. He forced his mind to heel. "It means there are people here in this time," he said huskily. "People, or something, who know how to make planes."
Michaelson nodded. "That would be my conclusion," he said.
"But that is impossible," Higgins flared. "If there had been civilizations in the past, we would have a record of them. I mean, we would have found their cities, even if the people had disappeared. We would have found traces of their factories, of their buildings—"