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The History of Continental Drift - Before Wegener
The theory of Continental Drift was formulated in the early 20th Century. Before then, many scientists and philosophers had for many centuries wrestled with many strange things they saw on the Earth's surface, from marine fossils in the mountains to the fit of South America into Africa, after the first near-accurate maps of the world were drawn in the 16th Century.
The following page describes the early thinking and their theories, although it excludes much detail about the story of Genesis. An assumption is made that you are familiar with the story, but if not, it can be referred to in the Alternative Views page, as it is a view still held by some.
The following discussion covers:
- Earliest Thoughts
- Archbishop James Ussher and Genesis
- The Rejection of Genesis
- Other Major Figures
- Early Theories
Earliest Thoughts
"In the Beginning, God said "Let there be Light" - and within a week, the world and Man had been created. According to both religious scholars and scientists up to only a few hundred years ago, little in the configuration of the world's continents (as seen through Western, Christian eyes) has changed since then.
Despite this long-held belief, evidence that suggests a different story has long been observed.
As early as 4 BC, Aristotle had puzzled over the existence of fossil marine creatures in rocks high above the sea, and in the 15th century, Leonardo da Vinci recorded the observation that fish once swam over the plains of Italy.
In 1570, an observation that rain, wind and waves 'wear away' the continents to such an extent that no land would remain unless new rock took its place was angrily rejected as questioning the 'supreme design of the Creator' - and so denounced as heresy.
Sir Francis Bacon
In 1620, Sir Francis Bacon studied the first crude maps of the world, drawn by the pioneering English and Dutch sailors. Like many others, he observed the strange similarities of the coasts of Africa and South America. He commented (in his famous Novum Organum) that these were 'no mere accidental occurrence' A few years later it was suggested that they were once one, but had been separated by the Flood.
Descartes and the Church
In 1634, Descartes reached the contrary and heretical conclusion that the creation of the Earth had been the result on ongoing natural processes, rather than the fully-formed product of a divine Creator. However, he did not publish these conclusions, for fear of the all-powerful Church. The Church, during those times, had supreme authority. In that same year, Galileo was living under house-arrest in Florence. He had had his books burned and had been threatened with torture - for expounding the view that the Earth revolves around the Sun and not the Sun around God's created Earth. Thus, most people of that time, scientists and scholars alike, accepted the Biblical account in Genesis - through both conviction, and fear of expressing any alternative view.
However, despite the fear to publish and speak out, a growing body of scientific observations was accumulating that did not easily fit with the Biblical story. To counter this heresy, Archbishop Ussher published a treatise that supported Genesis and that became an accepted explanation of the Creation of the Earth, as we see it today. In it, 'the Deluge' - the flood that Noah survived in his ark - conveniently and easily explained these problems away.
Archbishop James Ussher and Genesis
In 1650, Archbishop James Ussher, Anglican Archbishop of Armagh, Primate of all Ireland, and confident of King Charles I, used the Holy Bible to construct the chronology of the events described therein. He concluded that "upon the entrance of the night preceding" Sunday October 23rd, 4004BC, the world was created when God said "Let there be Light". Over the following 6 days, as described in Genesis, the land, plants, animals and man were created; and on the 7th day, He rested. ('Scientific consensus' now holds that the sequence of events as recounted in Genesis is correct, but the timescale somewhat contracted.) Ussher went on the place the date of "The Deluge" 1655 years later - Noah entered his ark on December 7th 2349BC and left it on Wednesday, May 6th the following year.
Ussher published his conclusions in 1650 and 1654, and these remained the basis of understanding for many centuries, accepted by both scientists and religious scholars.
Ussher was an intelligent and well-respected figure, held in high regard by the King, the people, the Church - and the scientists of his time. His treatise merely confirmed the conventional wisdom of the time, which was that the Earth was at most a few 1000 years old, that its features were in place at the time of creation, and that they had remained immovable ever since. Any obvious changes that could not be ignored, and the presence of marine fossils on mountain ranges, were accredited to The Deluge.
30 years later, following an increasing volume of evidence suggesting major changes to the world's configuration, Thomas Burnett published "The Sacred History of the Earth" (1681). This gave further explanatory depth to the cataclysmic events of the Deluge, to explain away these inconvenient and heretical observations.
The Rejection of Genesis
Despite valiant attempts to correlate scientific observation with the Biblical story, the onset of the 'Enlightenment' - the great upwelling of rational thought in the 18th Century - and the accumulation of scientific evidence, suggested a different picture. It became apparent that the Earth was much older, and had undergone massive changes since its early days, than was then popularly believed.
Les Époques de la Nature - Georges Louis Leclerc
In the mid-18th century, the first major rejection of the theory was conceived by George LeClerc, Comte de Buffon. He suggested that the Earth had formed out of a white-hot mass, torn from the Sun by astronomical force. Although the Church initially persuaded him not to publish, he finally reneged on that agreement, and in 1780 he outlined his ideas in the famed book "Epochs of Nature". Although his actual theories were soon rejected, his publication promoted the idea and (scientific) acceptance of open discussion. Logical thought and scientific investigation of geological history could, for the first time, progress beyond the limitations of the Biblical story.
From a review of "Époques de la nature":
'Having long meditated on the problem of the origin of the earth, [Buffon] published his famous Époques de la nature. In this work he arranged the history of the globe in six epochs - intervals of time of which the limits, though indeterminate, seemed to him none the less real. He tried indeed to form some idea of their duration on the basis of a series of ingenious experiments [which] possess the highest historical interest, first as the earliest recorded attempt to compute the probable age of the earth and of the planets from physical observations, and secondly as an epoch-making departure from the old and orthodox notion that our globe came into existence only some six thousand years ago...
'In breadth and grandeur of conception Buffon far surpassed the earlier writers who had promulgated theories of the earth. The rare literary skill with which, in his masterpiece, the Époques, he presented his views, enabled him to exercise a powerful influence on his contemporaries, to direct attention to the deeply interesting problems of which he wrote, and to give natural science a far wider popularity than it had before enjoyed... It was his great merit to have pointed out that the history of the earth is a long chronological record, the memorials of which are to be read in the frame-work of the globe itself, and to have himself applied the historical method to its interpretation. Nor were his services less conspicuous in breaking down the theological barrier which, after so many centuries, still blocked the way towards a free and unfettered study of the crust of the earth' (Giekie, The founders of geology, pp. 90-96).
Other Major Figures
Benjamin Franklin
In 1782, Benjamin Franklin joined the fray, observing "oyster shells mixed in stone" in a mountain in Derbyshire, England. He wondered how they could have been raised from their former habitat below the waves, and arrived at an astonishing conclusion that would only be appreciated by later generations:
"The crust of the Earth must be a shell floating on a fluid interior.... Thus the surface of the globe would be capable of being broken and distorted by the violent movements of the fluids on which it rested".
This thinking went no further at the time, but given the outlandish theories which posted-dated it, it is astonishingly accurate.
James Hutton
At the close of the century, James Hutton (later known as the 'founder of modern geology') observed his native Scottish rock formations, and deduced that the earth must be formed and reformed by natural processes - accumulation, erosion, heating and folding. These processes must have acted in the same general manner for many geological ages. Watching streams scour the hills, he reflected that "old continents are wearing away and new continents are forming in the bottom of the sea".
Whilst many still believed in Ussher's dates, Hutton's theory was breathtaking, largely because of its perception of the vastness of geological time.
His ponderous, obscure and little-read publication which first expressed these ideas was later simplified, and so reached a wider audience. 1805 saw the publication of "Illustrations of the Huttonian Theory of the Earth" which allowed many to share - if not agree with - this ideas.
Alexander von Humbolt
Contemporaneously, the German explorer and naturalist Alexander von Humbolt was rising questions on an even wider scope.
In 1799, he embarked on a 5 year expedition in South America, where he accumulated much information about plant and animal life, and landforms. During this trip, he realised that the similarities of Africa and South America went beyond that of an apparent 'fit' of their coastlines. Several mountain ranges that seemed to end on South America's eastern coast resumed on the western shores of Africa, and there were striking resemblances between the geological strata of the 2 continents - the mountains of Brazil, for instance, were the same as those of the African Congo.
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This was clear evidence of Francis Bacon's ideas of nearly 200 years earlier that the coastal pattern was not accidental coincidence.
(However; Humbolt still concluded that the Atlantic was a simply a valley - a permanent feature that had filled with the water during Noah's flood.)
Early Theories
Some of the early thinkers wrote down and published their observations and ideas, as quoted above. As evidence accumulated, others formulated detailed theories. The following 3 are described below:
The Contracting Earth
By the mid-19th century, a new theory had gained widespread acceptance. James Dwight Dana declared that the earth was cooling and contracting from a previous molten state. All geological features were caused by this contraction, and even the great mountain ranges were seen to be equivalent to the wrinkles in the skin of a drying apple.
Calculations led to a pronouncement that in cooling to its present temperature from a molten state over a period of about 100 million years, the Earth's circumference had contracted by hundreds of miles (so even more 100's of kilometres).
Despite some problems, this theory satisfied most geologists. "What we are witnessing is the collapse of the world" wrote Suess, a leading Austrian geologist.
In an interesting contrast, a present (early 21st century) theory (rejected by many) is that the Earth is expanding. In this later theory of expansion, the same geological features seen by Dana's theory of the contraction of the Earth to be wrinkles caused by shrinking, are seen to be cracks in the planet's surface as the world expands.
However flawed, this new theory of the contracting Earth explained many of the puzzles of the 19th century. A particular such problem was that of the worldwide spread of biological species that could not have crossed the oceans. Identical species of snakes, turtles and lizards are found in Africa and South America, whose ancestors cannot conceivably have swam the vast gulf between them. Fossil evidence has also linked India with Australia. Conversely, whilst Madagascar shares few biological similarities with nearby Africa, it shows a close biological heritage with India, 3000 miles (about 5000km) north.
In 1864, the existence of an ancient continent "Lemuria" was postulated. This had, it was suggested, once spanned the Indian Ocean and connected India to Madagascar. With the Earth's contraction, Lemuria sank below the waves, leaving only Madagascar above the sea. Sunken continents and land bridges were often cited as means for similar animals to pass to separated continents - perhaps Atlantis once linked [ to ].
In 1887, using the worldwide distribution of fossils as a guide, an early paleogeographic map was constructed. It proposed how the earth might have looked 190 million years ago, and linked Africa to South America, and India to Madagascar, by land bridges and now-gone continents. It was then generally believed that the disappearance of these land bridges had been caused by the cooling and contraction of the planet - but agreement was not universal. Some 30 years earlier, some speculation had it that all continents had once been a single mass on one side of the world, which had then had broken up. In 1858, a publication carried some convincing maps of that single continent, and the first suggestion that the continents had moved vast distances around the globe to reach their current positions. However; Noah's Deluge had again been cited as the cause of the break-up, and as this was already an unfashionable idea, the rest of the theory was never taken seriously.
Geological uplift
In 1735, it was discovered that mountains are in fact less dense than formerly assumed. The brilliant French scientist, Bouguer, was performing gravitational studies in the Andes of South America, and confidently expected to reveal a greater gravitational attraction of mountains to a plumb line.
In fact, he proved the exact opposite, an effect repeated by George Everest in similar studies in the Himalayas
Still assuming granite to be dense, it was suggested (by the French press) that the mountains might be hollow. However, the discovery also provided the basis for, and ultimately led to, the more acceptable theory of isostasy. This suggests that the 'light' rock of the mountains is 'buoyed up' by deep roots into the denser mantle - rather like icebergs floating in water with their bulk below the surface.
In 1855, George Airy pronounced "that the crust is in a state of equilibrium"; as mountains lose weight through the inevitable erosion by wind and water, they slowly rise up from below the surface. The effect is now used to explain the constant height of the Himalayas - the erosion rate that ought lower the mountains is countered by "isostatic rebound" as they become lighter, so float higher.(Increased compression from India's continuing movement northwards may also play a part).
This concept of geological uplift gained credence in 1870, when a small boat was navigated along tributaries of the Colorado River (USA) along the bottom of sheer rock canyons.
Despite first appearances, it was concluded "the canyons had not been cut down from top to bottom by the river. Rather, the river had stayed at a constant level, while the surrounding land had risen slowly upward during millions of years. The river, carrying tonnes of abrasive mud, sand and gravel every day, had scoured each successive layer as the rock moved up against it."
30 years later, Clarence Dutton's formal theory of isostasy was puiblished, explaining how different rock densities lead to an equilibrium. The lighter granite rises, and heavier basalt sinks. This caused major problems for the scientists who believed in the disappearance of (light, granite) continents and land bridges into the oceans, as proposed by the then-current theory of the Earth's contraction.
Furious scientific argument thus raged in the wake of the controversial publication.
'Mighty Creeping Movements'
In 1908, a paper presented to the Geological Society of America proposed that continents had not sunk, but had shifted horizontally. This they had done in a 'mighty creeping movement' to reach their present locations. The paper's author, Frank Taylor, based these deductions on his study of mountain ranges, which he believed could only be formed by titanic lateral pressures over long periods of time.
He rejected the idea of sinking continents and land bridges, but instead, supported an earlier proposal of a single primeval continent that had ruptured into many fragments, which had then moved.
As these fragments then collided into each other, the great mountain ranges we know today were thrown up.
This paper, for the first time, cited the Mid-Atlantic Ridge as a key to geological movement.
It was already known, even then, that a major undersea mountain range that ran centrally between, and parallel, to the coasts of Africa and South America. However, no significance had been given to this amazing observation.
Taylor recognised the ridge as the line of rifting between the 2 continents. He went on to claim that the ridge had "remained unmoved, whilst the two continents on opposite sides have crept away in nearly parallel and opposite directions".
However - his ideas were ignored or opposed by fellow scientists, and caused hardly a ripple.
18 months later, a very similar theory by the German Alfred Wegener caused as much disruption in the geological community as the collision of moving continents have caused to the face of the earth.
Please continue to read on, about Wegener's theory of Continental Drift.
For any comments, suggestions or contributions, please e-mail me at: portsdown@bbm.me.uk