James Hutton's 18th-century discovery at Siccar Point changed humanity's perspective on Earth's history and on time itself.
Siccar Point, probably the most famous geological site in the world, played a significant role in changing humanity's perspective on the history of the Earth, and even time itself. It was at this site that James Hutton, a Scottish farmer and polymath, discovered the concept of "deep time" by examining the layers of rock at the coastline. In the 18th century, almost everyone believed the Earth was somewhere between 4,000 and 10,000 years old, based on a literal interpretation of the Bible. According to BBC, Hutton believed that the Earth was far older, and it was a realization that would change the course of science.
As a classics student at the University of Edinburgh at just 14, Hutton already had a burgeoning interest in chemistry. He discovered how to isolate ammonium chloride from soot and began a business manufacturing it, which provided him with wealth for life. But Hutton's personal life had taken a turn for the worse after fathering an illegitimate son and being perceived as a man of "loose character" within Edinburgh society. He retreated to a series of farms near the Scottish-English border that he had inherited from his father, and his fascination with agriculture later turned his ever-questioning mind to the processes that formed the Earth and to the age of the Earth itself.
Hutton began to understand that the land was sculpted and shaped by gradual processes, all operating over immense timescales far longer than a few thousand years. After decades of observing and slowly piecing together his thoughts, he presented his findings in 1785 to a small academic group of philosophers at the Royal Society of Edinburgh. But to convince a wider audience, he knew he needed more evidence.
Hutton set off around Scotland seeking landscapes with clear junctions or unconformities, which he believed represented gaps in time between different geological features. As soon as he set eyes upon Siccar Point, he knew he had found what he had been searching for. His companion that day, philosopher and mathematician, John Playfair, later described the moment: "The mind seemed to grow giddy by looking so far back into the abyss of time."
The contrast between the vertical sheets of oceanic rock along the bottom of the cliff and the horizontal layers of sandstone high above was clearly visible. Hutton had discovered that the rocks forming the coastline at Siccar Point could not have been created in sudden cataclysms over just a few years or decades. The process must have taken much longer.
Today, we know that the oceanic greywacke rock was formed some 435 million years ago, while the sandstone was formed another 65 million years later. Hutton's realization that the formation and movement of these coastline rocks at Siccar Point couldn't have happened in sudden cataclysms over years or decades led him to conclude that the Earth was far older than people believed at the time.
Hutton's discovery of "deep time" at Siccar Point forever changed humanity's perspective on the history of the Earth and time itself. His work helped establish geology as a science, and it also influenced other fields of inquiry, from biology to history. Today, Siccar Point remains a site of historical and geographic importance and a place that attracts visitors from all over the world who want to see where Hutton made his groundbreaking discovery.