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this period of change so remotely distant, when I take into view some phenomena which have come under my observation since my residence in that country, together with others that have been related to me by gentlemen whose veracity I would be sorry to doubt.
In many places, the trees, instead of having their roots visibly diverging from their trunks, have them so buried in the earth, that they look like posts that have been driven into the ground by some powerful engine; and, in some of them, where accidental breaches in the banks of the river have exposed their roots, we can mark the extent of sediment accumulated by each year's inundation, from distinct sets of horizontal roots that burst from little fissures in their bark at regular distances, one above another. The distance between these roots differs in different situations, but in low situations I think about three inches might be estimated as the mean standard. From counting the several sets of these roots, in one or two trees, I concluded, that the short period of twenty-five years was sufficient to produce six feet of ground.
It will, perhaps, be said, that my geological inferences have been drawn from too slender premises, and that the laws which govern vegetables are too fortuitous in their issue, to afford data sufficiently determinate for our application in accounting for phenomena so thickly enveloped in the mists of time. My answer is, that St. Pierre[1] was not ashamed to enu-
- ↑ St. Pierre's Studies of Nature.
