It is obviously the case, namely, that there are two possible explanations of all phenomena which lie so far concealed in "the dark backward and abysm of time," that we can have no direct knowledge of the manner in which they were produced.
We may, on the one hand, suppose them to be the result of some very powerful cause, acting through a short period of time.

That is Catastrophism.

Or, we may suppose them to be caused by a much weaker force operating through a proportionately prolonged period.
This is the view of the Uniformitarians.

It is a question of _energy_ versus _time_ and it is _time_ which is the true element of the case.

An earthquake may remove a mountain in the course of a few seconds; but the dropping of the gentle rain will do the same, if we extend its operations over a millennium.