莱尔对均变论的形成和确立做出了重要的贡献。1830年1月，发表了《地质学原理》第一卷（1831年出版第2卷，1833年5月出版第3卷）。他坚持并证明地球表面的所有特征都是由难以觉察的、作用时间较长的自然过程形成的。他指出地壳岩石记录了亿万年的历史，可以客观地解释出来，而无需求助于《圣经》或灾变论，同时，他承认陆地的升降运动，把意大利塞拉比寺院的三根石柱（它们曾部分被海水淹没）作为《地质学原理》的刊头画，并指出斯德哥尔摩附近海面以上200尺的海生动物的贝壳说明陆地的上升。也就是说，要认识地球的历史，用不着求助超自然的力和灾变，因为通常看来是“微弱”的地质作用力 （大气圈降水、风、河流、潮汐等），在漫长的地质历史中慢慢起作用，就能够使地球的面貌发生很大的变化。莱尔强调“现在是认识过去的钥匙”，这一思想被发展为“将今论古”的现实主义原理，这种“将今论古”的科学方法对达尔文的影响很大。在莱尔逐步取代了居维叶之后，均变论在长达近一个世纪的时间里成为地质学的信条，奠定了现代地质学的科学基础。本世纪60年代以前的地质学教科书，几乎异口同声地说“莱尔用均变论统一说明了地质现象，建立了科学的地质学”。

生于苏格兰法弗夏区的金诺镇。1814年进入牛津大学，学习数学和古典文学，1816年改学法律，1821年进入林肯法学院。还在牛津大学时他选修了地质课，并参加了地质小组活动，受到了地质学 基础知识的训练，奠定了他从事地质学研究的基础。莱伊尔法学院毕业后，放弃律师工作热衷于地质学的研究，并做出卓越的贡献，享有崇高的声誉。早在1822年就当选为伦敦地质学会秘书，1849年当选为主席。1853年牛津大学授予名誉博士学位。1861年当选为英国皇家学会主席。1874年剑桥大学授予名誉博士学位，相继选为法国科学院通讯院士。1848年英国政府晋封他爵士称号。1861年代表伦敦大学出席了国会。他的主要论著《地质学原理》于1831-1833年共分三册相继出版。这是一部代表十九世纪进化论地质学的经典性作品，反映十九世纪地质学的理论发展水平，被誉为自然科学史上划时代的名著。莱伊尔历经十余年的艰苦努力，足迹遍及欧洲各地。在掌握了大量丰富的第一手地质资料的基础上，综合汲取各家之长，建立起自己的地质理论一现实主义原则和“将今论古”的方法，进而提出了渐进论，为地质学理论的发展起了推动作用。恩格斯在《自然辩证法》一书中，对莱伊尔的贡献，做过高度的 评价，指出：“在自然科学史上，对保守思潮打穿了“缺口”的杰出科学 成就有：第一个缺口：康德和拉普拉斯。第二个：地质学和古生物学(莱伊尔，缓慢进化论)…”。同时还指出：“只是莱伊尔才第一次把理性带进地质学中，因为他以地球的缓慢的 变化这样一种渐进作用，代替了由于造物主的一时兴发所起的突然革命”。

莱伊尔的科学道路也不是一帆 风顺的，其发展和成长过程更是曲折，甚至有过错误。他最早受他的老师贝克兰（Buckland）的影响，是一个水成论者，物种不变论者。对他的观点上的错误，恩格斯也给予了严厉的批判，指出“莱伊尔的观点的缺陷——至少在其最初的形式上一在于：他认为在地球 上起作用的各种力是不变的，无论在质或量上都是不变的。地球的冷却对他来说是不存在的；地球不是按照一定方向发展着，它只是毫无联系，偶然地变化着”。恩格斯的批判，主要针对他早期的论点，后来在达尔文的帮助下，放弃了物种不变论观点，遗憾的是，他的学生们未能对地质作用的发展演变，做根本的改正，甚至导致绝对化，盲目陷入了均变论和等速论。

For other people named Charles Lyell, seeCharles Lyell (disambiguation).Sir Charles Lyell, 1st Baronet,KtFRS(14 November 1797 – 22 February 1875) was a Britishlawyerand the foremostgeologistof his day. He is best known as the author ofPrinciples of Geology, which popularisedJames Hutton's concepts ofuniformitarianism– the idea that the earth was shaped by the same processes still in operation today. Lyell was also one of the first to believe that the world is older than 300 million years, on the basis of its geological anomalies. Lyell was a close and influential friend ofCharles Darwin.

Lyell was born inScotlandabout 15 miles north ofDundeein Kinnordy, nearKirriemuirinForfarshire(now inAngus). He was the eldest of ten children. Lyell's father, also named Charles, was a lawyer andbotanistof minor repute: it was he who first exposed his son to the study of nature.

The house/place of his birth is located in the north-west of theCentral Lowlandsin the valley of theHighland Boundary Fault. Round the house, in therift valley, is farmland, but within a short distance to the north-west, on the other side of the fault, are theGrampian Mountainsin theHighlands.His family's second home was in a completely different geological and ecological area: he spent much of his childhood atBartley Lodgein theNew Forest, England.

Lyell enteredExeter College, Oxfordin 1816, and attendedWilliam Buckland's lectures. He graduatedB.A.second class in classics, December 1819, andM.A.1821.After graduation he took up law as a profession, enteringLincoln's Innin 1820. He completed a circuit through rural England, where he could observe geological phenomena. In 1821 he attendedRobert Jameson's lectures in Edinburgh, and visitedGideon MantellatLewes

In 1832, Lyell marriedMary Hornerof Bonn, daughter ofLeonard Horner(1785–1864), also associated with theGeological Society of London. The new couple spent their honeymoon in Switzerland and Italy on a geological tour of the area.

During the 1840s, Lyell traveled to theUnited StatesandCanada, and wrote two popular travel-and-geology books:Travels in North America(1845) andA Second Visit to the United States(1849). After theGreat Chicago Fire, Lyell was one of the first to donate books to help found theChicago Public Library. In 1866, he was elected a foreign member of theRoyal Swedish Academy of Sciences.

Lyell's wife died in 1873, and two years later (in 1875) Lyell himself died as he was revising the twelfth edition ofPrinciples. He is buried in Westminster Abbey.Lyell was knighted (Kt), and later made a baronet (Bt), which is a hereditary honour. He was awarded the Copley Medal of the Royal Society in 1858 and the Wollaston Medal of the Geological Society in 1866. Mount Lyell, the highest peak in Yosemite National Park, is named after him; the crater Lyell on the Moon and a crater on Mars were named in his honour; Mount Lyell in western Tasmania, Australia, located in a profitable mining area, bears Lyell’s name; and the Lyell Range in north-west Western Australia is named for him as well. The jawless fishCephalaspis lyelli, from the Old Red Sandstone of southern Scotland, was named by Louis Agassiz in honour of Lyell.

Career and major writings

Lyell had private means, and earned further income as an author. He came from a prosperous family, worked briefly as a lawyer in the 1820s, and held the post of Professor of Geology atKing's College Londonin the 1830s. From 1830 onward his books provided both income and fame. Each of his three major books was a work continually in progress. All three went through multiple editions during his lifetime, although many of his friends (such as Darwin) thought the first edition of thePrincipleswas the best written.Lyell used each edition to incorporate additional material, rearrange existing material, and revisit old conclusions in light of new evidence.

Principles of Geology, Lyell's first book, was also his most famous, most influential, and most important book. First published in three volumes in 1830–33, it established Lyell's credentials as an important geological theorist and propounded the doctrine. It was a work of synthesis, backed by his own personal observations on his travels.

The central argument inPrincipleswas thatthe present is the key to the pastCharles Darwin. Lyell askedRobert FitzRoy, captain ofHMSBeagle, to search for erratic boulders on thesurvey voyage of theBeagle, and just before it set out FitzRoy gave Darwin Volume 1 of the first edition of Lyell'sPrinciples. When theBeagle

While inSouth AmericaDarwin received Volume 2 which considered the ideas ofLamarckin some detail. Lyell rejected Lamarck's idea of organicevolutionbelow, many of his letters show he was fairly open to the idea of evolution. In geology Darwin was very much Lyell's disciple, and brought back observations and his own original theorising, including ideas about the formation ofatolls, which supported Lyell's uniformitarianism. On the return of theBeagle(October 1836) Lyell invited Darwin to dinner and from then on they were close friends. Although Darwin discussed evolutionary ideas with him from 1842, Lyell continued to reject evolution in each of the first nine editions of thePrinciples. He encouraged Darwin to publish, and following the 1859 publication ofOn the Origin of Species, Lyell finally offered a tepid endorsement of evolution in the tenth edition ofPrinciples.

The frontispiece fromElements of Geology

Elements of Geologybegan as the fourth volume of the third edition ofPrinciples: Lyell intended the book to act as a suitable field guide for students of geology.The systematic, factual description of geological formations of different ages contained inPrinciplesgrew so unwieldy, however, that Lyell split it off as theElementsin 1838. The book went through six editions, eventually growing to two volumes and ceasing to be the inexpensive, portable handbook that Lyell had originally envisioned. Late in his career, therefore, Lyell produced a condensed version titledStudent's Elements of Geologythat fulfilled the original purpose.

Geological Evidences of the Antiquity of Manbrought together Lyell's views on three key themes from the geology of theQuaternary Periodof Earth history: glaciers, evolution, and theage of the human race. First published in 1863, it went through three editions that year, with a fourth and final edition appearing in 1873. The book was widely regarded as a disappointment because of Lyell's equivocal treatment ofevolution. Lyell, a devout Christian, had great difficulty reconciling his beliefs withnatural selection.

Scientific contributions

Lyell's geological interests ranged fromvolcanoesand geological dynamics throughstratigraphy,paleontology, andglaciologyto topics that would now be classified asprehistoric archaeologyandpaleoanthropology. He is best known, however, for his role in popularising the doctrine ofuniformitarianism.

An aerial photo of Vesuvius

Before the work of Lyell, phenomena such as earthquakes were understood by the destruction that they brought. One of the contributions that Lyell made inPrincipleswas to explain the cause of earthquakes.Lyell, in contrast focused on recent earthquakes (150 yrs), evidenced by surface irregularities such as faults, fissures, stratigraphic displacements and depressions.

Lyell's work on volcanoes focused largely onVesuviusandEtnaas opposed to the upheaval argument supported by other geologists.

Stratigraphy

Lyell's most important specific work was in the field ofstratigraphy. From May 1828, until February 1829, he traveled withRoderick Impey Murchison(1792–1871) to the south ofFrance(Auvergne volcanic district) and toItaly.In these areas he concluded that the recent strata (rock layers) could be categorized according to the number and proportion of marine shells encased within. Based on this he proposed dividing theTertiaryperiod into three parts, which he named thePliocene,Miocene, andEocene. He also renamed the traditionalPrimary,SecondaryandTertiaryperiods (now callederas) toPaleozoic,MesozoicandCenozoic, which nomenclature was gradually accepted worldwide.

Glaciers

Lateral moraine on a glacier joining the Gorner Glacier, Zermatt, Switzerland.

InPrinciples of Geology(first edition, vol. 3, Ch. 2, 1833)Lyell proposed thaticebergscould be the means of transport forerratics. During periods of global warming, ice breaks off the poles and floats across submerged continents, carrying debris with it, he conjectured. When the iceberg melts, it rains down sediments upon the land. Because this theory could account for the presence of diluvium, the worddriftbecame the preferred term for the loose, unsorted material, today calledtill. Furthermore, Lyell believed that the accumulation of fine angular particles covering much of the world (today calledloess) was a deposit settled from mountain flood water. Today some of Lyell's mechanisms for geologic processes have been disproven, though many have stood the test of time.His observational methods and general analytical framework remain in use today as foundational principles in geology.

Evolution

Lyell first received a copy of one ofLamarck's books fromMantellin 1827, when he was on circuit. He thanked Mantell in a letter which includes this enthusiastic passage:

In the second volume of the first edition ofPrinciplesLyell explicitly rejected themechanismof Lamark on thetransmutation of species, and was doubtful whether species were mutable.However, privately, in letters, he was more open to the possibility ofevolution:

This letter makes it clear that his equivocation on evolution was, at least at first, a deliberate tactic. As a result of his letters and, no doubt, personal conversations,HuxleyandHaeckelwere convinced that, at the time he wrotePrinciples, he believed new species had arisen by natural methods. BothWhewellandSedgwickwrote worried letters to him about this.

Later,Darwinbecame a close personal friend, and Lyell was one of the first scientists to supportOn the Origin of Species, though he did not subscribe to all its contents. Lyell was also a friend of Darwin's closest colleagues,HookerandHuxley, but unlike them he struggled to square his religious beliefs with evolution. This inner struggle has been much commented on. He had particular difficulty in believing innatural selectionas the main motive force in evolution.

Alfred Russel Wallacein 1862.

Lyell and Hooker were instrumental in arranging the peaceful co-publication of the theory of natural selection by Darwin andAlfred Russel Wallacein 1858: each had arrived at the theory independently. Lyell's data onstratigraphy

Although Lyell did not publicly accept evolution (descent with modification) at the time of writing thePrinciples,after the Darwin–Wallace papers and theOriginLyell wrote in his notebook:

Lyell's acceptance of natural selection, Darwin's proposed mechanism for evolution, was equivocal, and came in the tenth edition ofPrinciples.The Antiquity of Man(published in early February 1863, just before Huxley'sMan's place in nature) drew these comments from Darwin to Huxley:

In other respectsAntiquitytheologiansandhistorians