HUTTON AND SCOTLAND
A MAN AND PLACE OF THEIR TIME
James Hutton, son of Scotland, wealthy dilettante-yes—but scientist extraordinaire who first established the then unimaginable antiquity of the Earth and from Scotland’s hills its weathered soils and outcrops comes the understanding of the unchanging earth processes that formed it!
WHY IN SCOTLAND?
SCOTLAND—EUROPE’S COMPRESSED “GRAND CANYON” OF GEOLOGY.
When you look at a colored geological map of Scotland you get the impression of an accordion squeezed together by some earthly forces driving the Scotch land mass as if a force compressed it into a giant sandwich from the northwest. Exposed to view are most of the rock types you might see were the Grand Canyon spread out flat.
That concept is not from the actual history of Scotland, since Scotland today is a hodgepodge of earth crust fragments from afar, pasted up against England and Wales —accreted there by the process of continental drift. The process of moving segments of 2 to 6 mile thick Earth crust over the surface of the underlying mantle at the rate at which your fingernails grow (@ one or two centimeters per year). The process has been on going for a period of over four and a half billon years. Scotland was with its patches of distant lands accreted together with patches of other crustal plates pressed on to it from afar. In a real sense, Scotland was a natural geological laboratory and Hutton (and others after him) made great use of its rock diversity.
Geologically Scotland is uncommonly complex and diverse being, formed of five distinctive terranes separated by five major fault zones. The fault zones are places where the rock types are discontinuous, and where one block of rock has has (generally) moved relative to the other.
Such faults suggest that long periods of time have elapsed for the deposition of one of the blocks, its and consolidation into rock, then its alteration and movement.
Trekking from south to north in Scotland one can pass through the Upland Terrane, over the Southern Upland Fault, thence into the Midland Valley Terrane, over the Midland Boundary Fault, and into the Grampian Highland Terrane, over the Great Glen Fault, and into the Northern Highland Terrane, and finally over the Moline Thrust Fault, into the most northerly Hebridean Terrane.
In Scotland you can find exposures of sedimentary rocks which date in age from the Precambrian Era all through the complete Paleozoic Era, from the Cambrian Period, Ordovician limestones in the NW highlands , Silurian sandstones in the Southern Uplands, Devonian sandstones, Carboniferous Era mudstones and limestones, Permian and Triassic sandstones Jurassic and Cretaceous sandstones, mudstones. As well as Paleozoic volcanic igneous rocks, and Cenozoic deposits as well.
But not only were there interesting rocks to study..but talented, well trained people with wealth to support study and devoted to rationalism, free thinking and empiricism.
18TH CENTURY SCOTLAND
Scotland in the “Age of Enlightenment” 1707-1800. Scotland in the 18th century was in the forefront of the Industrial Revolution and the Scottish Enlightenment. The 1707 Act of Union of Scotland and England led to the formation of the United Kingdom. After 1707 the Scottish Parliament in Edinburgh was disbanded and representatives of Scotland, the parliamentarians and politicians were all forced to leave Edinburgh for London.
They left behind a city that had developed as the capital of a nation in the throes of the industrial revolution. As a result, the City had a well-developed infrastructure and architecture designed to support institutions of politics, justice, law, education, medicine, science, as well as the headquarters and leadership of the Church of Scotland. All of these institutions of prominence were left behind in the former capital.
At that time, though Scotland had only 20% of the population of England, but it had more than twice the number of universities. There were five great centers of higher learning in Scotland in1707 at: Edinburgh, Glasgow, Marischal, at King’s College in Aberdeen, and at St. Andrews.
The great city of Edinburgh, lost all its political power, there was no parliament and no King, but it remained with a wealth of native talent, intellectual infrastructure and expertise. These “left behind elements of society” appear to have been stimulated to excel, and to “thumb their noses” at the overarching political and military power which had departed for London.
Furthermore, besides having remnant institutions and well developed infrastructure, the 1707 union with England also opened Scotland to the UK’s extensive and expanding colonial markets. English colonies in North America from Canada to Georgia opened up a vast market with almost unlimited demand for Scottish manufactured goods. Scotland had the wealth and technology to supply these products. The Scotch profited from this cross Atlantic trade by importing lumber, forest products such as barrel staves, tobacco, rice, sugar, cotton, furs and dried fish, and exporting Scottish manufactured goods back to the colonies. This trade expanded their industrial output, increased employment, and made huge profits for investors.
The Scotch were also well positioned to take even greater advantage of cross-Atlantic trade by importing raw materials, repackaging them and with little further expense re-exporting colonial raw materials to Europe.
The hugely profitable tobacco trade was well developed in Glasgow, where merchants imported American tobacco, and then exported re-packaged tobacco products to France and Europe at great profit. These thriving import export, manufacturing, and other businesses all needed banking services, and these financial institutions flourished as well. The Royal Bank of Scotland was founded in 1727, at the height of this economic resurgence.
CITY OF EDINBURGH ( Pronounded:“Edin bro”)
For these reasons, those who lived in Edinburgh during the 18th century were well served by a thriving economy, well funded banks, by five great universities, well stocked libraries, multiple reading clubs, several scientific societies, museums and publishing houses that produced specialized periodical magazines in science agriculture, manufacturing and medicine.
The city was also enhanced by an elite group of philosophers, jurists, churchmen, scientists and professors who formed an intellectually elite middle class that was to dominate Scotland for much of the 18th century. Eventually this period was termed the age of Scottish “enlightenment”.
Among the many Scotsmen of note were: Robert Burns (poet), Adam Smith (economist), David Hume (philosopher),Robert Adam (architect), Joseph Black (chemist), John Hope (botanist), William Cullen (physician), James Hutton (geologist), John Platfair, . Many of these men knew each other, they met and discussed their work, they debated their ideas, they socialized at local clubs and scientific societies. What unified their work and achievements was their wholehearted embrace of the concept of “free thought”, and their conscious abandonment of the conceptual strictures of the past.
RATIONALISM, EMPIRICISM, FREE THINKING
An in born Scottish trait?
The Edinburgh elite were deeply influenced by “rationalism” and the associated ideas of social progress and free speech espoused by the French philosopher and scientist Voltaire (1694-1778).
But they also had among their midst a native of Edinburgh, the illustrious David Hume (1711-1776) who proposed a form of philosophical thought that emphasized observation and analysis. Hume was a proponent of empiricism, or the concept that all knowledge was based on observational evidence (he basis of inductive reasoning). Hume supported controlled experiments, and rejected a priori (i.e. from the past) reasoning, unsupported imaginings, revelations, and argument from ancient authority. Hume was one of the most influential philosophers of his time, who attempted to apply experimental methods to moral subjects.
18TH CENTURY SCOTCH DISCOVERIES
Josh Ward and Sulfuric Acid
In 1736 Joshua Ward of Glasgow, a Scotch pharmacist/chemist/entrepreneur, developed a process for the commercial production of sulfuric acid, is a strong acid widely used in industrial chemistry and in the production of hydrochloric and nitric acid . (KNO3 heat—>KNO2 + O2, S+O2–>SO2,SO3, SO3 + H2O= H2SO4). Sulfuric acid, called the “workhorse” acid was widely used to bleach cloth, to produce sodium bicarbonate needed in production of glass, soap, and dyes.
Ward set up an array of glass containers in which he heated the potassium nitrate, sulfur and water, to produce SO3 gas, which then reacted with the water in the glass to produce sulfuric acid . The process in glass containers permitted the reaction to proceed more rapidly than earlier production processes.
Though Ward published his process method it took him thirteen years to actually build the first large scale successful commercial sulfuric acid production plant in Scotland in 1749. It was a milestone in the chemical industry. A few years earlier in 1746 an English chemist/physician John Roebuck improved the process he had heard about by using larger (cheaper) vats made of sheets of lead to heat the sulfur potassium nitrate and water mixture to produce the acid.
John Black, Carbon Dioxide, Magneium, Beam-Balance andf Latent Heat
Professor John Black taught chemistry at Edinburgh University, while there, he discovered the element magnesium, and also isolated a gas that was heavier than air and snuffed out a burning candle— that gas, later identified as carbon dioxide. Black, while still a student, also invented the laboratory beam balance still used today in chemical analysis.
Black, observing the temperature of water as it boiled noted that the water remains at a constant temperature as the heat converts the water into a gas. Water absorbs heat to change into a gas and it releases that heat when it condenses back into a liquid. Black called the heat released when the water condensed as the “latent heat” of gases.
JAMES HUTTON, A MAN OF EDINBURGH
The course of James Hutton’s life was not a straight line to economic security and scientific eminence. He was born into an affluent 18th century Scottish family in 1726. Hutton’s father was a well to do merchant (possibly engaged in the cross Atlantic trade) who later became Edinburgh City Treasurer. The family resided in Edinburgh in relative affluence. Hutton’s father had acquired through inheritance and investment two large farm properties in the countryside close to the English border. Hutton’s father died in 1729 when James was only three years of age. These working farm properties and other family resources must have provided a more than adequate income, for young James, his mother and sisters at this time. The farm incomes, family investments and savings continued to support Hutton in the manner of a privileged upper class young man. In preparation to enter university, Hutton attended Edinburgh’s local grammar school, and at the age of 14 was admitted to the University of Edinburgh, to study classics.
It It may have been at Edinburgh where outstanding professors taught the natural sciences that Hutton became interested in chemistry. Popular professors in maths and science often gave free lectures that Hutton may have attended. It is likely that it was during this period that Hutton’s keen interest in chemistry and mathematics developed. Perhaps this new obsession with science was responsible for his abandonment of his formal classics studies which ended abruptly and unhappily.
Attorney Apprentice
After leaving university his family apprenticed him to an attorney when he was 17. But he found that work dull and uninteresting, as well. An apocryphal story of Hutton and a boyhood friend and co-worker (James Davie) claims the two young assistants often entertained office colleagues with chemical experiments, may explain why he and Davie left that career in law.
Physician
Perhaps to pursue his interest in chemistry, Hutton moved on to medicine which, in those days of blurred scientific relations, chemistry played an important role. A year later in 1744, he had become a physician’s assistant and enrolled at the Medical School of the University of Edinburgh (1744-1747). Perhaps this career path was the only one he could follow to satisfy his passion for chemistry. After four years at Edinburgh he transferred to the University of Paris, and by 1749 had completed his dissertation for the doctorate degree under Professor Joachim Schwartz of Leiden University, in the Netherlands . At Leiden University on September 3, 1749 he successfully defended his dissertation on “Blood and the Microcirculation” and received his doctorate in medicine on Sept 12, 1749. Hutton left the Netherlands and returned to London England, where, as a newly minted “doctor of medicine” he loitered around in that entertaining city for nine months. But by the summer of 1750 we find that he has returned to Edinburgh.
Chemist and Entrepreneur
There, he began to pursue chemical experiments with his boyhood friend James Davie. Perhaps these two young avocational chemists were aware of the great success of their countryman Joshua Ward, who in 1749 for the first time developed a very successful industrial process for the commercial production of sulfuric acid.
Stimulated by Ward’s success the two friends worked on the production of sal ammoniac (ammonium chloride) —another widely used industrial chemical essential as a metal cleaning agent and in the important process used to dye fabrics.
Sal Ammoniac is a salt which formed white or gray crystalline encrustations around volcanic fumaroles or vents in volcanically active zones. The whitish ammonium salt or Ammonium Chloride (NH4CL) was first used and collected in Roman times around volcanic vents in Libya and Crete. A well-known collection site were, fumaroles near the Temple of Zeus Ammon (Amun) in the Libyan desert. As a result of its collection locale, the salt was called Sal Ammoniac (or “Salt of Ammon”). The compound NH4 or “ammonia” thus was named after Zeus of Ammon in Lybia.
In the 18th century Sal Ammoniac was collected from fumaroles around Mt Vesuvius in Italy. As a result of its means of collection, by hand, with strenuous walks into this essential chemical was often scarce and expensive. Hutton and Davie planned to make it more available to a growing industrializing nation, and produce a profit for themselves.
In the 18th century this ammonium salt was used extensively to dissolve oxide coatings on metals before the “tinning process”, and for soldering metals. Tinning of copper cooking pots was an important and common use of this chemical. It was also used extensively in leather tanning and in dyeing fabrics. It is a component human medicines. It functions as an expectorant in human cough remedies and served widely as “smelling salts”, and was also used in many veterinary preparations as well.
Aware that Egyptians reported collecting this salt from the ceilings of caves in which camels had been kept and where camel dung had been stored, Hutton and David attempted to developed an industrial means of replicating this process. By the end of 1751 Hutton and Davie had discovered a means to sublimate sal ammoniac crystals by burning organic substances such as dung, and soot and condensing (more accurately sublimating) salt crystals from the fumes.
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The two formed a partnership and jointly invested in a manufacturing plant to produce the substance commercially This Hutton-Davie enterprise was highly successful and continued on for many years enhancing Hutton’s income and permitting him to pursue other interests.
Ammonium chloride occurs in nature, often found in volcanic terranes as a sublimate or encrustations around volcanic vents or fumaroles. Sal ammoniac or ammonium chloride (NH4Cl) was (and remains) a widely used chemical. It is a salt of ammonia (NH3) a weak base, and hydrochloric acid (HCL) a strong acid which forms NH4CL is a crystalline white powder that is easily soluble in water, forming a slightly acid solution.
Agriculture
Being a successful chemist and entrepreneur did not end Hutton’s obsession with scientific discovery. Hutton had inherited two working farms from his father, one in the lowlands of the southwest part of Scotland close to the English border called Slighshouses and another in more hilly country further north. By 1751 the peripatetic Hutton had turned his active mind to improving farming practices . With this transition to farming in mind— Hutton characteristically determined to learn as much as he could about farming as he did about all of his other passions.
For this reason he left Scotland to spend a year (1752-1753) studying agricultural practices in East Anglia in England..an area renowned for its advanced agriculture practices at the time. East Anglia is a land of low relief, with mild climate and fertile loam soils. The soils of this region are underlain by sedimentary shales, limestones and sandstones. In many places the natural process of weathering soils in which minerals such as feldspars are chemically altered to clays and minerals rich in iron produce red iron oxides clay and silica. The end process often reveals remnant resistant minerals such as flint nodules and organic remains such as fossilized or mineralized marine shells.
Geology and Geologic Time
In his agricultural studies Hutton had the opportunity to journey to other parts of England as well. The soils of England vary widely and Hutton must have become aware of the fact that the rich lime-soils of southern and eastern England (such as Essex and East Anglia) were often characterized as having large amounts of prominent chert and flint pebbles and cobbles. These were so common, that farmers went to great effort to remove them so as to ease the wear of these hard minerals on the metal plow, and to prepare a proper seed bed for crops.
These “pick-out” nodules the size of baseballs or melons (cobble sized) were so common that they were often used as a cheap building material for country farmhouses and other structures. Chert and flint nodules were often used as a low cost fill in brick trimmed wall-structures. Brick was expensive, while chert nodules could be simply collected from pick out piles along farm fields.
Hutton, who studied the rock outcrops in these areas was fully aware that these same flint and chert nodules were also found embedded in solid rock as siliceous concretions within the limestone outcrops of bedrocks of all these regions. He must have quickly become aware of the fact that limestone was easily broken down or weathered by the action of with mild acids found in soils, while the insoluble chert nodules were left as a residue of the original solid rock that he observed below the soil or in near-by outcrops.
First Observations On Soil and Time
As a result of these observations he came to the conclusion that the soils of this area were likely the end product of the chemical alteration of the local limestone rock. As the limestone rocks bearing nodules decomposed they left behind the insoluble chert and flint pebbles and cobbles.
These common nodules were the proof of the essential, elemental process that soils are the end product of the chemical alteration of subsurface rocks. But his observations as a farmer who examined his fields each year, included the insight that this process was a very slow one, likely taking thousands of years for limestone rock to weather into soil leaving behind chert and flint nodules.
Hutton spent fourteen years farming during which time he continued to improve agriculture methods, and also followed his passion for discovery—in particular those involving earth processes. These years were critical ones in developing his insights into the slow processes of earth chemistry and breakdown of rocks as well as the antiquity of the Earth
Member of Royal Society
In 1767 Hutton returned to Edinburgh to a city with an active and robust intellectual life. He became an active member of a remarkable group of men who founded the Royal Society of Edinburgh and made that city an almost unrivaled center of intellectualism and experiment.
In 1788 Hutton and James Hall took a boat trip along the southeast coast of Scotland. They stopped at Siccar Point a promontory that fac[ed the North Sea. There Hutton and Hall observed a jumble of rocks that most observers would have concluded were the result of some past cataclysmic event which happened in a brief violent past, leaving the rocks crumbled and distorted.
But Hutton saw something very different. The base of the rock outcrop were marine fine gray sandstones and mudstones ( deposited under the sea). But the formerly horizontal beds had been altered and were oriented vertically. A zone of non deposition and erosion separated the rocks above. Above these vertical gray bedded rocks, were a slightly sloping bed of a coarse red sandstone with rounded pebbles.
Hutton later wrote that the historic record in the rocks at Siccar Point indicated: 1)The lower fine gray sedimentary beds were deposited in an ocean. 2) These sediments were buried, lithified and folded up into an upright (vertical position) and subsequently raised above sea level. 3) As a result of their elevated position, they were slowly eroded away (by the same processes that eroded Hutton’s farm soils). 4) The marine beds must have remained for a long period of time exposed to the air, to rain, and to erosion. That period of erosion was represented by a gap in depositon and a surface (called an unconformity*) in with evidences of weathering and erosion of the underlying upturned marine beds. That period of erosion was represented by a gap in deposition called an unconformity* ( 5) As time passed these gray marine beds were again buried. This time by coarse grained red, terrestrial sediment derived from a near-by highlands or mountain range (Hutton recognized that the small rounded pebbles in the sediments must have traveled a long way from their high elevations source probably in streams ) The red sandy sediment washed down over the gray vertical beds, and covered them up. It was in time also leithified. 6) Later earth movements tilted the whole region ]upward to their present aspect.
Siccar Point was an outcrop which told of multiple geologic events, and of long slow processes which must have taken enormous periods of time to complete.
After some 25 years of diverse study, field work, consultation, and writing, after visiting Siccar Point in 1788, Hutton prepared a paper on his “Theory of the Earth” to be read to the Royal Society in two sessions. His theory was soon after formally published in his book: Theory of the Earth (1788)
James Hutton of Edinburgh, Scotland (1726-1797) was a tepid student of the classics, a failed attorney’s assistant, a non-practicing physician, a part-time gentleman-farmer, an avocational chemist, an inveterate entrepreneur, a working soil scientist, field naturalist and passionate geologist whose seminal life work “Theory of the Earth” (1788) would establish the immense age of the earth,and the concept that gradual change over long periods of time was responsible for the Earth’s present aspect. Thus this seminal work established, both the unimaginable age of the Earth, as well as the fact that everyday slow processes are responsible for its topography. It also elevated geology from an avocational hobby to that of a key element of natural science.
John Playfair (1748-1819) Scottish minister mathematician and professor of natural philosophy at University of Edinburgh, and author of: Illustrations of the Huttonian Theory of the Earth (1802). Playfair was a colleague of Hutton, who wrote “Illustrations” to clarify and expand and make more accessible to the public the ideas that Hutton espoused;
Charles Lyell, (1797-1875) Scottish geologist, attorney, avocational geologist and author of immensely popular Principles Geology (1830). In which. in three volumes (last one in 1833) establishes in clear readable language that: 1) The Earth is very old. 2) It was shaped and altered by the natural processes that operate today. 3) These processes operate at the same uniform intensity as today. He establishes the three watchwords of geology: Time Change Uniformity.
Geological science was born…in Scotland..a truly Scotch affair.
*in this case the unconformity is termed an “angular unconformity” I.e. the base beds are folded upward.
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