and in mineralogical make-up that, "were it not for fossil evidence, one
would naturally suppose that a single formation was being dealt with"
(McConnell); and these conditions are "not merely local, but persistent
over wide areas" (A. Geikie), so that the "numerous examples" (Suess) of
these conditions "may well be cause for astonishment" (Suess).

A still more astonishing thing from the standpoint of the current
theories is that these conformable relations of incongruous strata are
often _repeated over and over again in the same vertical section_, the
same kind of bed reappearing alternately with others of an entirely
different "age," that is, appearing "as if _regularly interbedded"_ (A.
Geikie) with them, in a manifestly undisturbed series of strata.

Here again we have a very formidable series of facts whose gravamen is
directed wholly against the artificial distinctions in age between the
different groups of fossils; and their argument is an eloquent plea that
the fossils are neither older nor younger but all of a similar age.

5. Our last fact demands a somewhat more extended consideration; but it
may be stated in advance briefly as follows:

In very numerous cases and over hundreds and even thousands of square
miles, the conformable conditions specified in the previous fact are
exactly reproduced _upside down_; that is, very "old" rocks occur with
just as much appearance of natural conformability on top of very "young"
rocks, the area in some instances covering many hundreds of square
miles, and in one particular instance in Montana and Alberta covering
about five or six thousand square miles of area.

The first notable example of this phenomenon was discovered at Glarus,