thanks to the long-continued labours of the first two, and mainly to
those of Sir Charles Lyell, has gradually passed from the position of a
heresy to that of catholic doctrine.

Applied within the limits of the time registered by the known fraction of
the crust of the earth, I believe that uniformitarianism is unassailable.
The evidence that, in the enormous lapse of time between the deposition
of the lowest Laurentian strata and the present day, the forces which
have modified the surface of the crust of the earth were different in
kind, or greater in the intensity of their action, than those which are
now occupied in the same work, has yet to be produced. Such evidence as
we possess all tends in the contrary direction, and is in favour of the
same slow and gradual changes occurring then as now.

But this conclusion in nowise conflicts with the deductions of the
physicist from his no less clear and certain data. It may be certain that
this globe has cooled down from a condition in which life could not have
existed; it may be certain that, in so cooling, its contracting crust
must have undergone sudden convulsions, which were to our earthquakes as
an earthquake is to the vibration caused by the periodical eruption of a
Geyser; but in that case, the earth must, like other respectable parents,
have sowed her wild oats, and got through her turbulent youth, before we,
her children, have any knowledge of her.

So far as the evidence afforded by the superficial crust of the earth
goes, the modern geologist can, _ex animo_, repeat the saying of Hutton,
"We find no vestige of a beginning--no prospect of an end." However, he
will add, with Hutton, "But in thus tracing back the natural operations
which have succeeded each other, and mark to us the course of time past,
we come to a period in which we cannot see any further." And if he seek