Vestiges of the natural history of creation / ... greatly amended by the author ; an introduction by Rev. George B. Cheever. [Anon].

  • Robert Chambers
Date:
1845
Catalogue details

Licence: Public Domain Mark

Credit: Vestiges of the natural history of creation / ... greatly amended by the author ; an introduction by Rev. George B. Cheever. [Anon]. Source: Wellcome Collection.

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    The highest part of the oolitic formation presents some phenomena of an unusual and interesting character, which demand special notice. Immediately above the upper oolitic group in Buckinghamshire, in the vicinity of Wey- mouth, and other situations, there is a thin stratum, usually called by workmen the dirt-bed, which appears, from incon- testable evidence, to have been a soil, formed, like soils of the present day, in the course of time, upon a surface which had previously been the bottom of the sea. The dirt-bed contains exuvise of tropical trees, accumulated through time, as the forest shed its honors on the spot where it grew, and became itself decayed. Near Weymouth there is a piece of this stratum, in which stumps of trees remain rooted, mostly erect or slightly inclined, and from one to three feet high ; while trunks of the same forest, also silicified, lie imbedded on the surface of the soil in which they grew. Above this bed lie those which have been called the Wealden, from their full development in the Weald of Sus- sex ; and these as incontestably argue that the dry land forming the dirt-bed had next afterwards become the area of brackish estuaries, or lakes partially connected with the sea; for the Wealden strata contain exuvise of fresh- water tribes, besides those of the great saurians and chelo- nia. The area of this estuary comprehends the whole south-east province of England. A geologist thus confi- dently narrates the subsequent events : “ Much calcareous matter was first deposited [in this estuary], and in it were entombed myriads of shells, apparently analogous to those of the vivipara. Then came a thick envelope of sand, sometimes interstratified with mud ; and, finally, muddy matter prevailed. The solid surface beneath the waters
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