James Hutton

James Hutton (1726 - 1797)
"The Father of Geology"

Advocated Uniformitarianism as a basis of geology

  Hutton was an early advocate of Uniformitarianism, the theory that geological formations could be explained by observable processes operating over very long periods of time. He presented his "Concerning the System of the Earth" in 1785, in which he argued

"The solid parts of the present land appear in general, to have been composed of the productions of the sea, and of other materials similar to those now found upon the shores. Hence we find reason to conclude:

    1st, That the land on which we rest is not simple and original, but that it is a composition, and had been formed by the operation of second causes.
    2nd, That before the present land was made, there had subsisted a world composed of sea and land, in which were tides and currents, with such operations at the bottom of the sea as now take place. And,
    Lastly, That while the present land was forming at the bottom of the ocean, the former land maintained plants and animals; at least the sea was then inhabited by animals, in a similar manner as it is at present.
 Hence we are led to conclude, that the greater part of our land, if not the whole had been produced by operations natural to this globe; but that in order to make this land a permanent body, resisting the operations of the waters, two things had been required;

    1st, The consolidation of masses formed by collections of loose or incoherent materials;
    2ndly, The elevation of those consolidated masses from the bottom of the sea, the place where they were collected, to the stations in which they now remain above the level of the ocean."

He famously concluded with the phrase, "The result, therefore, of our present enquiry is, that we find no vestige of a beginning,–no prospect of an end." Charles Lyell, who was strongly influenced by Hutton, also concluded, "The past is the key to the present."

Hutton made observations of several geological discontinuities, where rocks of different time were overlain on each other.


Discontinuity at Salisbury Crags near Edinburgh

Granite is upthrust through overlying metamorphic rock, so as to suggest molten igneous rock penetrating upward through rocks modified under pressure. Other discontinuities show layers of horizontal sedimentary sandstone overlain on layers tilted almost vertically.

Text material © 2020 by Steven M. Carr