As before said, we cannot wonder at the former general acceptance of Catastrophistic doctrines.

Even in the light of our present widely-increased knowledge, the series of geological monuments remains a broken and imperfect one; nor can we ever hope to fill up completely the numerous gaps with which the geological record is defaced.

Catastrophism was the natural method of accounting for these gaps, and, as we shall see, it possesses a basis of truth.

At present, however, catastrophism may be said to be nearly extinct, and its place is taken by the modern doctrine of "Continuity" or "Uniformity"-- a doctrine with which the name of Lyell must ever remain imperishably associated.
The fundamental thesis of the doctrine of Uniformity is, that, in spite of all apparent violations of continuity, the sequence of geological phenomena has in reality been a regular and uninterrupted one; and that the vast changes which can be shown to have passed over the earth in former periods have been the result of the slow and ceaseless working of the ordinary physical forces--acting with no greater intensity than they do now, but acting through enormously prolonged periods.

The essential element in the theory of Continuity is to be found in the allotment of indefinite time for the accomplishment of the known series of geological changes.