(Wikipedia). .

             At Siccar Point on the Berwickshire coast, Hutton noticed an unconformity in layers of sedimentary rocks. (Wikipedia). Now referred to as Hutton's Unconformity, this area helped Hutton understand the cyclical nature of geology. "The lower part of the cliff shows layers of grey shale tilted to lie almost vertically, then immediately above this the upper part of the cliff shows near horizontal layers of red sandstone." (Wikipedia). The layers led to Hutton's conclusion that there were cycles of deposition, interspersed with tilting and erosion, that led to the creation of different strata of rock. .

             By 1770, Hutton's interest in geology "had become an obsession, and his home was transformed into a vast museum of stones and fossils; it also contained a functioning laboratory for chemical analysis of his many geological specimens." (Aronson). On March 7, 1785 and April 4, 1875, Hutton's theory was read at meetings of the Royal Society of Edinburgh. (Wikipedia). Hutton's views were supported by an immense amount of research and observational data. It was later published in 1788 in Volume I of the Transactions of the Royal Society of Edinburgh. In 1795, Hutton published a two volume version of his theory, which consisted of his 1788 publication, material from several of Hutton's shorter papers, and a review of alternative theories. (Wikipedia). Unfortunately for Hutton, his scientific skills were not matched by his writing skills, and the publications did not hasten the spread of his theory outside of the scientific community.

             One reason for this may be that Hutton's theories directly opposed many of the theories of the day. For example, Abraham Gottlob Werner's Neptunist theory posited that all rocks came from a single enormous flood. On the contrary, Hutton's theory, later referred to as Plutonism posited that the hot core of the earth created new rock in a never-ending process.