If the oldest recorded astronomy was already highly developed, who had done the work that preceded it? Jean Sylvain Bailly (1736–1793) took that question as evidence of a missing people. The Egyptians, Indians, and other ancient societies appeared to him as inheritors of knowledge whose beginnings lay elsewhere. Their observations might preserve clues to the homeland of teachers whose names and history had disappeared.
Astronomy gave the proposal a form more exact than a general appeal to lost wisdom. Observations of the heavens could be examined for signs of when and where they had been made. Bailly hoped to move from such clues to the conditions under which an earlier population had lived. A history absent from the surviving chronicles might be reconstructed from the knowledge passed down in its place.
His conclusions carried him into northern Asia and, in later speculation, toward an Arctic Atlantis in a once warmer world. He discussed the proposed early civilization with Voltaire (1694–1778), who was already interested in antiquity outside biblical chronology. Their sympathy on that larger question did not produce agreement about the northern homeland. Voltaire resisted a journey into the past that had become more extensive than the evidence seemed to warrant.
Bailly’s reconstruction joined the prestige of calculation to conjectures about migration, climate, and the survival of learning. The calculations did not establish every historical inference made from them, but they helped explain why a lost civilization could appear to be a serious subject of investigation. The first teachers no longer had to be recovered through a prophet’s name or a supposedly revealed book. Their successors’ knowledge itself could be presented as evidence that they had once existed.