A chance reference to the potency of aqua regia , introduced by way of illustration in a lecture on logic, turned his young fancy to thoughts of chemistry. He followed up the subject in a lexicon; and, when presently apprenticed to a lawyer, he spent his time in making chemical experiments rather than in copying papers.
Hutton studied in Edinburgh, Paris, and Leyden, where he graduated; but he never practised. His chemical experiments, wonderful to relate, found commercial application; and, with an income in prospect, he turned to agriculture. For experience he went to Norfolk, and it was in England that he first developed an interest in geology. Reprints and Permissions. Modern geologic processes operate slowly. Hutton realized if these processes formed rocks, then the Earth must be very old, possibly hundreds of millions of years old [ 21 ; 22 ].
Prior to the acceptance of uniformitarianism, scientists such as German geologist Abraham Gottlob Werner and French anatomist Georges Cuvier thought rocks and landforms were formed by great catastrophic events.
Based on his study of large vertebrate fossils, he was the first to suggest species could go extinct. However, he thought new species were introduced by special creation after catastrophic floods [ 21 ; 24 ]. His ideas were falling into obscurity when Charles Lyell, a British lawyer and geologist , wrote the Principles of Geology in the early s and later, Elements of Geology [ 21 , 25 ].
Lyell and his three-volume Principles of Geology had a lasting influence on the geologic community and public at large, who eventually accepted uniformitarianism and millionfold age for the Earth [ 21 ]. The principle of uniformitarianism became so widely accepted, that geologists regarded catastrophic change as heresy. This made it harder for ideas like the sudden demise of the dinosaurs by asteroid impact to gain traction.
Darwin used uniformitarianism and deep geologic time to develop his initial ideas about evolution. The next big advancement, and perhaps the largest in the history of geology, is the theory of plate tectonics and continental drift.
Dogmatic acceptance of uniformitarianism inhibited the progress of this idea, mainly because of the permanency placed on the continents and their positions. Ironically, the slow and steady movement of plates would fit well into a uniformitarianism model. There is no sure test available by which it could be shown that the Devonian age, for instance, as outlined in the strata of Europe, did not begin millions of years earlier or later than the period whose records are said to represent the Devonian age in America.
In attempting to decide such details as this, mineralogical data fail us utterly. Even in rocks of adjoining regions identity of structure is no proof of contemporaneous origin; for the veritable substance of the rock of one age is ground up to build the rocks of subsequent ages.
Furthermore, in seas where conditions change but little the same form of rock may be made age after age. It is believed that chalk-beds still forming in some of our present seas may form one continuous mass dating back to earliest geologic ages.
On the other hand, rocks different in character maybe formed at the same time in regions not far apart - say a sandstone along shore, a coral limestone farther seaward, and a chalk-bed beyond.
This continuous stratum, broken in the process of upheaval, might seem the record of three different epochs. Paleontology, of course, supplies far better chronological tests, but even these have their limitations. There has been no time since rocks now in existence were formed, if ever, when the earth had a uniform climate and a single undiversified fauna over its entire land surface, as the early paleontologists supposed.
Speaking broadly, the same general stages have attended the evolution of organic forms everywhere, but there is nothing to show that equal periods of time witnessed corresponding changes in diverse regions, but quite the contrary. To cite but a single illustration, the marsupial order, which is the dominant mammalian type of the living fauna of Australia to-day, existed in Europe and died out there in the tertiary age.
Hence a future geologist might think the Australia of to-day contemporaneous with a period in Europe which in reality antedated it by perhaps millions of years. All these puzzling features unite to render the subject of historical geology anything but the simple matter the fathers of the science esteemed it.
No one would now attempt to trace the exact sequence of formation of all the mountains of the globe, as Elie de Beaumont did a half-century ago. Even within the limits of a single continent, the geologist must proceed with much caution in attempting to chronicle the order in which its various parts rose from the matrix of the sea.
The key to this story is found in the identification of the strata that are the surface feature in each territory. If Devonian rocks are at the surface in any given region, for example, it would appear that this region became a land surface in the Devonian age, or just afterwards.
But a moment's consideration shows that there is an element of uncertainty about this, due to the steady denudation that all land surfaces undergo. The Devonian rocks may lie at the surface simply because the thousands of feet of carboniferous strata that once lay above them have been worn away.
All that the cautious geologist dare assert, therefore, is that the region in question did not become permanent land surface earlier than the Devonian age. But to know even this is much - sufficient, indeed, to establish the chronological order of elevation, if not its exact period, for all parts of any continent that have been geologically explored - understanding always that there must be no scrupling about a latitude of a few millions or perhaps tens of millions of years here and there.
Regarding our own continent, for example, we learn through the researches of a multitude of workers that in the early day it was a mere archipelago. Journey to the Center of Earth. There, before a couple of other members of the Scottish Enlightenment, he staked his claim as the father of modern geology.
Aa Hutton told the skeptics who accompanied him there by boat, Siccar Point illustrated a blasphemous truth: the Earth was old, almost beyond comprehension. Hutton proposed that the Earth constantly cycled through disrepair and renewal. Exposed rocks and soil were eroded, and formed new sediments that were buried and turned into rock by heat and pressure. That rock eventually uplifted and eroded again, a cycle that continued uninterrupted.
His ideas were startling at a time when most natural philosophers—the term scientist had not yet been coined—believed that the Earth had been created by God roughly 6, years earlier. The popular notion was that the world had been in a continual decline ever since the perfection of Eden.
Therefore, it had to be young. At Siccar Point, Hutton pointed to proof of his theory: the junction of two types of rock created at different times and by different forces.
Gray layers of metamorphic rock rose vertically, like weathered boards stuck in the ground. They stabbed into horizontal layers of red, layered sandstone, rock only beginning to be deposited.
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