Hutton's innovative 1785 theory based on Plutonism visualised an endless process of rocks forming under the sea, being uplifted and tilted, then eroded to form new strata under the s
In 1788 the sight of Hutton's Unconformity at Siccar Point convinced Playfair and Hall of this extremely slow cycle, and in that same year Hutton memorably wrote "we find no vestige of a beginning, no prospect of an end".
y, Hutton's comprehension of endless deep time as a crucial scientific concept was developed into uniformitarianism by Charles Lyell in his Principles of Geology (1830–33).