In the second half of the 18th century, Edinburgh was at the center of the Scottish Enlightenment, an extraordinary community of brilliant people united by two cardinal themes: the primacy of reason in the affairs of mankind and the conviction that the principal value of knowledge is to be of practical use to humanity. The Enlightenment community included, in addition to James Hutton, David Hume, possibly the greatest philosopher ever to write in the English language, Adam Smith, arguably the world’s greatest economist, Joseph Black, chemist and discoverer of carbon dioxide, and Adam Ferguson, who through his emphasis on a civil society initiated the discipline of sociology. These four and many more were companions who corresponded frequently and socialized with joy, especially in the (in)famous Oyster Club. Part of the magic that they created was that they all understood and enjoyed the breadth of each other’s expertise.
The flair of the Scots in the development of our collective knowledge was widely recognized in Europe and America. Thomas Jefferson, himself a man of the Enlightenment, wrote, “So far as science is concerned, no place in the world can pretend to competition with Edinburgh.” Ben Franklin who visited Scotland twice, in 1759 and 1771, recalled his earlier visit to Edinburgh as “the densest happiness” that he had ever experienced. The Scots reciprocated when Franklin received an honorary doctorate from the University of St. Andrews and was the first foreigner elected to the Royal Society of Edinburgh.
Who Was James Hutton?
Concept for the viewpoint overlooking Siccar Point. The vertical column is the proposed design for waypoints along the Deep Time Trail. Concept prepared by CMC Associates.
James Hutton was stricken by the polymath bug: a doctor of medicine as well as a farmer who brought new ploughing techniques to Scotland and studied crops, including the earliest varieties of potato, and developed the use of lime to improve soils. He measured the effect that altitude has on temperature and developed a theory of rain. He completed his education in Paris (where he probably received a geological education) and Leiden. He was also a successful chemist and businessman with a factory in Edinburgh making salammoniac, also known as aluminum chloride, which is used in dyeing. As a shareholder he used his geological expertise in the construction of the Forth and Clyde Canal.
He authored the first two volumes of a theory of the Earth, and a third volume was published posthumously. In addition, he wrote a three-volume treatise, “The Principles of Knowledge.” A hitherto unpublished treatise on agriculture will be published this year as part of the Hutton tercentenary celebrations. The latter establishes Hutton as that wonderful ideal – a practical scientist.
Deep Time, Among Other Geological Insights
It was during his years as a farmer in the south of Scotland that he developed his geological ideas from studying the land around his farms. He recognized that the soils were gradually being eroded by wind and rain and more soil formed from the rocks and organic matter. This was a slow process. He also recognized that the bedrock was made of two types of rock: the schistose and the red sandstone. Both were made of sand grains eroded from older rocks during the slow process of soil formation and erosion. He deduced that the schistose was harder and more deformed and that the red sandstones were younger and less deformed. His theory was that the schistose had been buried, heated, turned into rock and folded, uplifted and eroded and hence new sand formed, also later buried, heated, turned into rock and uplifted and eroded once more. A series of cycles with “no vestiges of a beginning and no sign of an end.” His theory needed evidence, and he deduced from mapping the two types of rock that he could find the junction – a classic, and maybe first use of our modern scientific method!
He set sail with two friends, John Playfair and James Hall and they found Siccar Point – a beautiful spot with a brilliant three-dimensional exposure of the unconformity. Playfair recorded the event with the words, “The mind seemed to grow giddy by looking so far back into the abyss of time.”
This was the first proof that the Earth is millions or billions of years old.
Hutton knew of a third type of rock forming the land of Scotland: granite. Existing consensus suggested that granite was the primeval rock, underlying all else and precipitated from a primal ocean. Hutton argued to the converse; granite and other related rocks had once been molten – magmatic and could be produced at any time in the history of the Earth. Rock exposures proving his point by demonstrating the intrusive nature of granite were located in Glen Tilt in the Highlands of Perthshire. Other exposures making his point were located on Edinburgh’s Salisbury Crags, although the igneous rocks here are not granite. So Hutton recognized the critical role that heat played in controlling the form of the planet.
“Irrefragable” indeed – a wondrous word that Hutton used to confirm and conclude his argument. He defines erosion and places it within the confines of his theory of the Earth. In so doing he adds another challenge to our search for the truth. Gaps in the record of the rocks that we now recognize as unconformities.
Some readers will have visited Siccar Point, as it is only 35 miles from Edinburgh, but it is not sign-posted and involves a walk across fields to the top of a steep grassy cliff, which defeats many visitors. There are some information boards, but for such an historically important site (the first to be described in the International Union of Geological Sciences’ “100 Most Important Historical Geological Sites”) there is so much more that can be done. We think that with better information and better access we can use the site to promote the importance and impact of geology on our lives. The nearby village of Cockburnspath marks the end of long-distance footpaths along the coast and the end of the Southern Uplands Way, which is a geological extension of the Iapetus Ocean and the Appalachian Way in America.
Hutton’s Enduring Legacy
The spectacular view of Hutton’s Unconformity from the cliff top view point. Photograph by Angus Miller
Hutton’s name was given to Scotland’s largest independent research institute in 2011, the James Hutton Institute, which today studies all the subjects he did, is home to the National Land and Soil Survey of Scotland and develops new crops and ways of managing our land. The institute also has world-class facilities, especially in mineralogy, that are used in exploration in various parts of the world.
To celebrate the tercentenary of Hutton’s birth, Edinburgh Geological Society has commissioned experts to put together a “Deep Time Trail” based on a series of way points with information about the route and the history of geology, and its impact on our lives. These points will highlight the role of geology in our lives, with information on the landscape, farming and key features: the largest cement works in the UK, which used the local limestone, shale and coal all from the same quarries; one of Scotland’s two nuclear power stations; an onshore and an offshore windfarm and, of course, the North Sea and its oil and gas resources.
We hope to get this new route to a viewpoint at the top of the cliff in place by the summer, with a further phase in 2027 to build a stairway down to the unconformity.
If you would like to make a donation toward the project, we estimate we require around $600,000. We plan to reward significant donations. We are delighted that we have copies of John Clerk of Eldin’s “Lost Drawings” from Hutton’s “Theory of the Earth,” donated by the family of John Clerk. Other unique gifts include a “Hutton Hat” – hand-knitted, showing Hutton’s three most significant outcrops (Glen Tilt, Siccar Point and Salisbury Crags).
We will be delighted to welcome our American colleagues to Edinburgh and help visitors visit Siccar Point and indeed other geological sites, particularly those linked to Hutton.
You can find more information and donate to the project via: www.crowdfunder.co.uk/p/siccar-point, which will run until the end of November.