On 3 June 1726, the Hutton family of Edinburgh welcomed a new member: little James. James Hutton would go on to become a scientist, physician, chemical naturalist, experimental agriculturalist, and the first person to put forth the idea of uniformitarianism—the assumtion that the same natural laws and processes that operate in the universe now have always operated in the past and apply everywhere in the universe. It’s one of the fundamental principles of geology, earning him the title ‘Father of Modern Geology.’
James was well educated, attending the University of Edinburgh at the age of 14 and training as a physician in Paris and Leyden, where he received his DM in 1749. He was back in Edinburgh in the mid 1750s and, with a friend, built up a profitable chemical works that manufactured crystalline salt used for dyeing, metalworking, and smelling salts. He also experimented with plant and animal husbandry on a farm he owned in Berwickshire, where he also started to become interested in meteorology and geology. He left the farm in 1764 to take a geological tour of the north of Scotland, and then moved back to Edinburgh in 1768.
In Edinburgh, he—rather appropriately—built a house overlooking Salisbury Crags and became one of the most influential people in the Scottish Enlightenment, becoming friends with John Playfair, David Hume, and Adam Smith. Because if one must have friends, they may as well be some of the foremost thinkers of your time, right?
Hutton continued studying the rock formations he saw around him, and after 25 years of work his Theory of the Earth; or an Investigation of the Laws Observable in the Composition, Dissolution, and Restoration of Land Upon the Globe was read to the Royal Society of Edinburgh in two parts (part one was, presumably, just the title). In his Theory, Hutton postulated that the earth was formed of organic mass and ‘collections of loose or incoherent materials’ that were eroded off the land by air and water, deposited as layers in the sea, and then formed into stone by heat and uplifted into new land. He spent the next few years travelling around Scotland, collecting evidence. The Theory was published in 1788, three years after it was first read.
Naturally, his ideas met with opposition. The popular theory of the time, known as the Neptunist theories, held that all rocks had been formed by a single flood, a notion in direct opposition to Hutton’s ideas. His theory also brought the concept of deep time into the discussion, which essentially meant that he was claiming the earth was much, much older than most people believed. Those who preferred a theological notion of the earth’s age weren’t happy about that at all (and they still aren’t).
His ideas, while not very widely read at the time, influenced Charles Lydell, who restated James’s concept of an infinitely repeating cycle in his books, which were eagerly read by a young geologist named Charles Darwin on his long journey aboard the Beagle.