An
upper, called in Germany Keuper, which consists, atop, of the rich
red marl, below them, of sandstones, and of those vast deposits of
rock-salt, which have been long worked, and worked to such good
purpose, that a vast subsidence of land has just taken place near
Nantwich in Cheshire; and serious fears are entertained lest the town
itself may subside, to fill up the caverns below, from whence the
salt has been quarried. Underneath these beds again are those which
carry the building-stone of Runcorn. Now these beds altogether, in
Cheshire, at least, are about 3,400 feet thick; and were not laid
down in a year, or in a century either.
Below them lies a thousand feet of sandstones, known in Germany by
the name of "Bunter," from its mottled and spotted appearance. What
lies under them again, does not concern us just now.
I said that the geologists called these beds the Trias; that is, the
triple group. But as yet we have heard of only two parts of it.
Where is the third?
Not here, but in Germany. There, between the Keuper above and the
Bunter below, lies a great series of limestone beds, which, from the
abundance of fossils which they contain, go by the name of
Muschelkalk. A long epoch must therefore have intervened between the
laying down of the Bunter and of the Keuper.
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