Note 30 — THE TESTIMONY OF THE ROCKS. (continued 6)

If I do not introduce here the argument founded on the great age of certain gigantic trees, such as the Baobab of intertropical Africa, or the Taxodium of South America, it is not because I have any reason to challenge the estimates of Adamson or Candolle. The one tree may have lived its five thousand, the other its six thousand, years; but as the grounds have been disputed on which the calculations respecting their vast age have been founded, and as they cannot be reëxamined anew by the reader, I wholly omit the evidence, in the general question, which they have been supposed to furnish.