Lyell, Charles (1797–1875)

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LYELL, CHARLES (1797–1875)

Charles Lyell was a founder of modern British geology. One of his most important contributions to science concerned the rates at which the earth's internal energy was released to affect the shape and form of its crust and thus to create the landscape we know today. Geological changes such as creation of valleys, mountain formation, deposition of sediments, and the like were not in his view caused by occasional "catastrophes" but rather the results of ordinary geological processes operating over an immense period of time. In other words the release of energy to produce geological change has occurred at a rate similar to that of the present time, and is largely uniform over the earth's long history. This doctrine of uniformitarianism has been rightly attributed to Lyell, though others before him (e.g., James Hutton) had expressed similar views.

Lyell was born on November 17, 1797, at Kinnordy near Forfar in Scotland. His father was a wealthy landowner with passions for both Italian literature and natural history. His mother came from Yorkshire and while he was still very young the family moved to England, taking a lease of a large house on the fringe of the New Forest in Hampshire. The boy was sent to schools in the locality, though he showed little evidence of scholastic promise. In 1816 he went to Exeter College, Oxford, to read classics, but he also attended lectures by William Buckland, a professor of geology. The effects of these lectures were reinforced by books from his father's ample library and by an encounter with Gideon Mantell, a doctor in the neighboring county of Sussex, renowned for his study of the fossils then being discovered in the chalkbeds and on the coast of southern England.

Lyell's 1819 Oxford degree was in classics, and he then began to study law at Lincoln's Inn, London. However, weak eyesight precluded much reading at that time, and this gave him a reason for further geological study in lectures, field studies, tours, and so on. He became a fellow of the Geological Society in 1819, and four years later was made one of its joint secretaries. He undertook geological tours in France, the west country of England, and the Scottish Highlands. A visit with Buckland to Glen Roy revealed to them the now famous Parallel Roads, three raised seabeaches now believed to be of glacial origin but even then posing great problems for conventional geology.

The central problems that Lyell was to address in the next few years involved detailed mechanisms of geological change, the age of the earth; and rates of energy release. The most popular view of geological history had proposed a series of great convulsions or "catastrophes" involving immense amounts of energy, alternating with longer periods of relative quiescence. Most famously, the biblical Flood of Noah was invoked to explain the present crust of the earth, including the regular strata of fossil beds. People who favored water as the chief agent of change ("diluvualists") had to contend with others who thought that fire was chiefly responsible ("vulcanists"). But each believed in a relatively short period of time for it all to happen, and sometimes drew confirmation from certain biblical data that could be interpreted to suggest a date of creation a mere few thousand years ago. Much support for this view was given by Buckland and by his Cambridge counterpart Adam Sedgwick, though both were later to change their minds. The opposite views of James Hutton were less popular, though Lyell was increasingly inclined toward them. One of several events that proved critical in his experience was a visit to Sicily in 1828. Before crossing the volcano Etna he had observed strata at the base of the mountain that seemed comparatively recent. Discovering similar deposits on the opposite side he concluded that the vast bulk of Etna rested on what were, in geological terms, recently recent rocks. Hence a vast age for the whole earth was indicated, and he embarked on a crusade for his uniformitarian ideas, publishing his monumental Principles of Geology in the early 1830s (and many subsequent editions thereafter). This work brought him lasting fame.

His legal practice largely forgotten, Lyell now devoted the rest of his life to promoting his doctrines and to traveling extensively. In 1832, at the new King's College, London, he became the first professor of geology, a post he occupied for only two years. He received from the Royal Society its Royal Medal in 1834, and a year later he became president of the Geological Society. He became much involved with the Great Exhibition in London in 1851 and in the British Association. He received a knighthood in 1848 and a baronetcy in 1864.

The influence of Charles Lyell on science was profound. Among the recipients of his Principles was a young naturalist embarking on a long sea voyage. This was Charles Darwin, who came to develop a strong interest in geology. He also accepted much of Lyell's arguments and, while his own theory of evolution was being formed, relied extensively on Lyellian arguments for an immensely old earth. He became a good friend as well as a disciple, though even in the 1860s Lyell was reluctant to give Darwin his public support, as he saw how thin the fossil evidence really was for transmutation of species. Not all scientists became enthusiastic Lyellians, however. William Thomson (Lord Kelvin) opposed him over the age of the earth, arguing on largely thermodynamic grounds for a shorter time span than Lyell or Darwin wanted. Only with the discovery of subterranean radioactivity were Kelvin's estimates shown to be erroneous and a Lyellian time scale rendered more credible. However, that of all the uniformitarians in the nineteenth century Lyell was the most extreme, and no one identified completely with a literal interpretation of uniformitarian change. There was too much evidence of catastrophic releases of energy in volcanic eruptions, flash flooding, and earthquakes for most people to deny their massive influence of earth history. Today a modified, and reduced, uniformitarianism seems more likely to fit the facts. Lyell's extreme views were probably related to a religious inclination to Unitarianism, which denies God's intervening activity in history through Christ, just as uniformitarianism cannot allow catastrophic interventions in geology. However, Lyell outwardly remained a member of the Church of England.

In 1842 he married Mary Horner, daughter of Leonard Horner, warden of the University of London. Lyell died in London on February 22, 1875.

Colin A. Russell