Sedgwick, Adam

views updated May 14 2018


(b. Dent, Yorkshire, England 22 March 1785; d. Cambridge, England, 27 January 1873)


Sedgwick was the second son of Richard Sedgwick, vicar of the rural parish of Dent. From a local grammer school he went to Trinity College. Cambridge, where he graduated in 1808 with distinction in mathematics. He was elected a fellow of Trinity in 1810 and was ordained in 1817. He never married, and Trinity College remained his home for the rest of his life.

In 1818 Sedgwick was elected Woodwardian professor of geology at Cambridge and immediately took to his new work with boundless energyand enthusiasm (his later assertion of his complete ignorance of geology at this time probably was exaggerated). He made his first geological expedition that summer, and became a fellow of the Geological Society of London later in the year. In 1819 he played a leading part in the founding of the Cambridge Philosophical Society, which was designed to promote the study of the natural sciences at Cambridge; and the same year he gave the first of his annual courses of lectures on geology (a series that he continued without interruption until 1870). Although Sedgwick’s lectures were, until the latter part of his life, optional and extracurricular, they were immensely popular; and their influence on successive generations of Cambridge students, and hence on the shaping of English educated opinion on geology, is hard to overestimate.

Sedgwick’s lecturing style was clear and vivid, and he had a direct and informal manner that made him accessible to and popular with students. But he found the formal composition repeatedly was delayed by recurrent ill health dating from a serious breakdown in 1813) and by his political activities and administrative responsibilities within the college and the university. His published works, therefore, hardly reflect the full extent of his achievement.

Sedgwick inherited a geological collection some-what enlarged from Woodward’s original bequest; but he himself expanded it during his long tenure of the chair into one of the finest geological museums in the world, partly through his own and his student’s collecting activities, and partly through purchasing fine specimens and collections with his own resources or with funds raised from public appeals. In 1841 a new museum buildings was opened to accommodate this rapidly growing collection; by the present Sedgwick Museum was erected as a memorial to him.

Sedgwick was president of the Geological Society of London from 1829 to 1831, and of the British Association at its first visit to Cambridge in 1833. In 1834 his appointment as a prebendary of Norwich gave him greater financial independence (the stipend of his chair was very small), but at the cost of requiring his residence at Norwich for part of every year for the rest of his life.

In politics Sedgwick was one of the most prominent Liberals at Cambridge, and was ion the forefront of the movement for university reform; Prince Albert, on becoming chancellor of the university in 1847, chose him to act as his:secretary” at Cambridge, and Sedgwick was later (1850–1852) a member of the royal commission on the reform of the university.

Sedgwick began his geological work under the influence of William Conybeare, and his earliest major studies were on the stratigraphy of the problematical and poorly fosiliferous deposits of the New Red Sandstone. In a monofraph published in 1829 he successfully used the distinctive Magnesian Limestone of northeastern England as a key to these strata, and was able to correlate them with the classic successions in Germany. This work showed Sedgwick to be a field geologist with an exceptional flair for grasping the regional significance of local details. The wider relevance of its conclusions lay in his interpretation of the strata as the products of long-continued processes, and in his emphasis on the srtrata as conformable “connecting links” from the Coal Measures below to the Lias (Jurassic) above. The same emphasis on stratigraphical continuity is evident in his joint work with Rodetick Murchison on the eastern Alps at about the same period, in which he clearly was concerned to bridge the apparent faunal break between “Secondary” and Tertiary strata.

Sedgwick therefore naturally welcomed some aspects of Charles Lyell’s work; in his presidential addresses to the Geological Society in 1830 and 1831 he agreed with Lyell that incalculably vast periods of time must be inferred for many geological events, and he retracted his earlier view (derived from William Buckland) that a single paroxysmal episode could account for all the “dilivial” deposits. But in reviewing the first volume of Lyell’s Principles of Geology he sharply criticized Lyell’s confusion of different meanings of “uniformity.” He agreed that the “primary laws of matter” were “immutable,” but he felt it was “a merebly gratuitous hypothesis” to assume that the geological processes based on those laws must have been rigidly uniform in their intensity throughout earth-history: uniformity in the latter sense had to be tested by empirical observation, not assumed a priori.

In comformity with this empiricist program, Sedgwick approved Élie de Beaumont’s theory of occasional paroxysmal elevation of mountain ranges, because it maded explicable many common pjhenomena (local folding of strata and local unconformities) in terms of events that, although abrupt and uncommon in occurrence, were perfectly natural in their mechanism. Similarly, he rejected Lyell’s assertion of steady-state uniformity in the organic realm, because the facts of the fossil record seemed to indicate unequivocally a gradual approach to the “present system of things.” Above all, Sedgwick felt that the geologically recent appearance of man was “absolutely subversive” of Lyell’s Huttonian conslusion.

Sedgwick’s most important geological work, which led to the foundation of the Cambrian system, seems to have been motivated by a desire to penetrate the fossil record back to its farthest limits, and to demonstrate that life had indeed had a begining in time. Some of his earliest fieldwork was an attempt to unravel the complex structure of the old rocks of Devon and Cronwall, and later he studied in detail those of the Lake District (where for many years he enjoyed the friendship of William Wordsworth). In the classic paper “Remarks on the Structures of Large Mineral Masses” (1835) he combined his mathematical training with his skill as a field geologist in the first clear analysis of the effects of diagenesis and low-grade metamorphism. In particular, his exposition of the distinction between stratification, jointing, and slaty cleavage provided the crucial technical key for the interpretation of the structure of regions with complex folding.

This had already enabled him, as early as 1832, to discover the essential sturucture and succession of the ancient rocks of North Wales (on his first expedition there, in 1831, he gave Charle Darwin his first training aa a field geologist). In the same years Murchison was studying apparently younger “Transition” strata in the Welsh Borderland. During their first and only joint study (1834) of the relation between their two areas, Murchison assured Sedgwick that his strate (later termed “Silurian”) lay wholly above Sedgwick’s “Cambrian” (so named in 1835), although there was clear—and not unexpected—faunal similarity between Murchison’s Lower Silurian strata and Sedgwick’s Upper Cambrian Bala series.

Their collaboration continued fruitfully in their solution of the anomalous problem of the slaty rocks of Devonshire, where De La Beche’s discovery of Carboniferous plants in rocks of ancient appearance had seemed for a time to threaten the validity of both Murchison’s and Sedgwick’s stratigraphy. They worked closely in discovering first that the anomalous fossils had come from a syncline of slaty rocks of Carboniferous age, and then that the older rocks in the region were not Silurian or Cambrian but the lateral equivalents of the Old Red Sandstone, which they termed “Devonian,” This interpretation was confirmed by a joint expedition to the Continent in 1839.

Sedgwick then turned his attention back to the problem of the Cambrian strata in Wales, as part of a larger program for a synoptic work (never completed) on all the Paleozoic strata of Britain. Although he could not point to a Cambrian fauna as distinctive as Murchison’s Silurian fauna, he rightly emphasized that the vast thickness of the Cambrian strata and the apparent beginning of the fossil record within them justified their status as a “system” of comparable importance. Indeed, he underlined their theoretical significance by including them with the Silurian in a broader category of “Protozoic.” He was therefore disconcerted and eventually exasperated when Murchison claimed that the upper (and fossiliferous) part of his Cambrian was nothing other than Murchison’s Lower Silurian. Murchison gradually extended this claim until he had annexed virtually the whole of the Cambrian and reduced it to a synonym of Lower Silurian.

Sedgwick later was angered by what he regarded as editorial tampering with a crucial paper on the subject submitted to the Geological Society. His stratigraphical nomenclature was altered, apparently in the interests of editorial uniformity, and possibly in innocence of the massive theoretical and personal implications. Reacting with characteristic vehemence, he later broke off al dealings with the Society.

Only gradually did Sedgwick detect the root cause of the controversy. Murchison earlier had misinterpreted the order of succession of his Lower Silurian strata in their type area, so that they were not in fact younger than Sedgwick’s Upper Cambrian Bala series, but of the same aga. Even more seriously, Sedgwick found in 1854 that Murchison had confused some Upper Silurian strata (May Hill sandstone) with these much earlier Lower Silurian strata (Caradoc series), thus giving the Silurian faunas a spurious uniformity down into Sedgwick’s Upper Cambrian.

But Murchison naturally was reluctant to admit these errors, and his position as head of the Geologica Survey (from 1855) allowed him to retain his interpretation in all the Survery’s official publications. What had begun as a controversy with important implications for the understanding of the earliest part of the fossil record gradually degenerated into a priority dispute between two equally obstinate old men. The conflict was not settled until much later, when the discovery of earlier faunas in Wales rehabilitated the term Cambrian for what had been Sedgwick’s Lower Combrian; and an “Ordovician” system was proposed irenically for the disputed strata (that is, Sedgwick’s “Upper Cambrian” and Murchison’s “Lower Silurian”) between the newly retricted Cambrian and Silurian systems.

The Geological Society acknowledged the outstanding value of Sedgwick’s work in 1850 (before he was estranged from it) by awarding him their highest honor, the Wollaston Medal; and in 1863 the Royal Society, to which he had been elected in 1830, awarded him the Copley Medal.

Sedgwick was seventy-four when Darwin’s Origin of Species was published, but his rejection of his pupil’s evolutionary theory was not simply a consequence of old age. Thirty years earlier, while welcoming naturalistic explanations for “diluvial” deposits), he had felt that no purely natural mechanism could ever account for the origin of new organic species. This belief was grounded in his strong sense of the “designful” beauty of organisms: although he was not primarily a paleontologists, his favorite lecture subject was the adaptive significance of fossil mammals. But his concept of teleology was philosophically unsophisticated, and like Paley (whose work had influenced him deeply) he simply wished the contemplation of organic design to nourish the sense of wonder that would lead the mind toward God.

Any theory of the transmutation of species by natural means therefore seemed to Sedgwick to threaten this preparatory function of natural theology and to lead to a “train of monstrous consequences.” Above all, since he saw clearly that whatever applied to other species ultimately just apply to man, the consequences of any evolutionary theory seemed to him to include the denial of the reality if the “moral” realm. Although a devout Christian, Sedgwick was no fundamentalist in religious matters: he was a prominent member of the Board Church party within the Anglican Church, and was greatly concerned to see progressive science and enlightened theology working independently toward an ultimate synthesis of truth. But this meant that he was as much concerned to expose the pretensions of a naïve materialism that undermined man’s moral responsibility as he was to attack simplistic “reconciliations” between geology and Scripture. Thus in his presidential addresses of 1830 and 1831 he criticized the popular “Scriptural geologists” even more vehemently than the proponents of transmutation. His influential Discourse on the Studies of the University (1833) linked a reassertion of the place of geology within the tradition of natural theology with a trenchant criticism of utilitarian mora philosophy; and the same concerns later were expressed vehemently in a major anonymous review (1845) of Robert Chambers’ Vestiges of the Natural History of Creation.

Sedgwick was angered not only by the inaccuracies and pseudoscientific pretensions of Chambers’ unsigned book: more fundamentally he feared that the specious plausibility of its all-embracing principle of naturalistic “development” would undermine the sense of personal responsibility that he believed was basic to the nature of man in society. He reiterated his views even more vehemently in a vastly enlarged fifth edition of the Discourse in 1850; by the time Darwin sent him a copy of the Origin of Species, Sedgwick’s antipathy to the “materialistic” tendencies of evolutionary theories had become so obsessive that his reaction was predictable.

By the end of his long life Sedgwick had in effect survived into a new period in the history of science; and although he was widely admired and even loved as a warmhearted and noble character, many of his scientific views seemed remote and antiquated. But in his prime he had been one of the most distinguished geologists within an exceptionally talented generation; and his concern for the broader implications of science had left an enduring mark on the place of science in university education.


I. Original Works. Sedgwick’s more important earlier works include A Syllabus of a Course of Lectures on Geology (Cambridge, 1821); “On the Origin of Alluvial and Diluvial Formation,” in Annals of Philosophy, n.s. 9 (1825), 241–247, and 10 (1825), 18–37; “On the Geological Relations and Internal Structure of the Magnesian Limestone, and on the Lower Portions of the New Red Sandstone Series...,” in Transactions of the Geological Society of London, 2nd ser., 3 , pt. 1 (1829), 37–124; “Address[es] to the Geological Society, Delivered on the Evening of the Anniversary...” in proceedings of the Geological Society of London, 1 (1830), 187–212, and (1831), 281–316; “A Sketch of the structure of the Eastern Alps...,” in Transaction of the Geological Society of London, 2nd ser., 3 , pt. 2 (1832), 301–420, written with Murchison; A Discourse on the Studies of the University (Cambridge, 1833; 5th ed., 1850; repr. Leicester, 1969); “Remarks on the Structure of Large Mineral Masses, and Especially on the Chemical Changes Produced in the Aggregation of Stratified Rocks During Different Periods After Their Deposition,” in Transaction of the Geological Society of London, 2nd ser., 3 pt. 3 (1835), 461–486; “Introduction to the General Structure of the Cumbrian Mountains...,” ibid., 4 , pt. 1 (1835), 47–68; and “A Synopsis of the English Series of Stratified Rocks Inferior to the Old Red Sandstone,” in Proceedings of the Geological Society of London, 2 (1838), 675–685, and “Supplement [to the same],” ibid., 3 (1841), 541–554.

In the 1840’s he published “On the Physical Structure of Devonshire, and on the Subdivisions and Geological Relations of Its Older Stratified Deposits, &c.,” in Transactions of the Geological Society of London, 2nd ser., 5 pt. 3 (1840), 633–704, written with Murchison; “On the Distribution and Classification of the Older or Palaeozoic Deposits of the North of Germany and Belgium, and Their Comparison With Formations of the Same Age in the British Isles,” ibid., 6 , pt. 2 (1842), 221–301, written with Murchison; “Three Letter Upon the Geology of the Lake District Addressed to W. Wordsworth, Esq.,” in John Hudson.ed., A Complete Guide to the Lakes... (Kendal, 1842)—two further letters were published in later eds. (1846, 1853); “On the Older Palaeozoic (Protozoic) Rocks of North Wlaes,” inQuarterly Journal of the Geological Society of London, 1 (18445), 5–22; and [Anonymous review of “Vestiges of the Natural History of Creation,” inEdinburgh Review, 82 (1845), 1–85.

His last works include A Synopsis of the Classification of the British Palaceozoic Rock With a Systematic Description of the British Palaeozoic Fossils in the Geological Museum of the University of Cambridge (Cambridge, 1851–1855), the description of fossils by Frederick McCoy; “On the Classification and Nomenclature of the Lower Palaeozoic Rocks of England and Wales,” in Quarterly Journal of the Geological society of London, 8 (1852), 136–168;a nd “On the May Hill sandstone, and the Palaeozoc System of England,” in Philosophical Magozine, 4th ser., 8 (1854), 301–317, 359–370.

University Library, Cambridge, his a large collection of scientific letters to Sedgwick; his geological collections and field notebooks are in the Sedgwick museum, Cambridge.

II. Secondary Literature. The principal biographical source is John Willis Clark and Thomas McKenny Hughes, The Life and Letters of Adam Sedgwick ... , 2 vols. (Cambridge, 1890), which contains balanced assessments of Sedgwick’s geological work from a late nineteenth-century viewpoint but relatively little of his more strictly scientific correspondence.

For an important modern essay on the cultural milieu of Sedgwick’s work, See Walter F. Cannon, “Scientists and Broad Churchmen; An Early Victorian Intellectual Network,” in Journal of British Studies, 4 (1964), 65–88. The biography by Clark and Hughes contains a fairly full list of Sedgwick’s work, excluding items published anonymously but including most of his political pamphlets and other writings as well as his scientific papers.

M. J. S. Rudwick

Adam Sedgwick

views updated May 17 2018

Adam Sedgwick

The English geologist Adam Sedgwick (1785-1873) was the founder of the Cambrian system, the first period of the Paleozoic geologic era.

Adam Sedgwick was born on March 22, 1785, at Dent in his ancestral region of the Yorkshire Dales. In 1804 he entered Trinity College, Cambridge, which became his chief home for the rest of his life. After being made a fellow in 1810, he was ordained; he later became a canon of Norwich. In 1818 he was elected to the professorship of geology, not because he knew anything about geology but on his general merits. However, he began enthusiastically to study the subject, giving lectures and making geological tours, but he constantly allowed himself to be diverted by business irrelevant to his geological work.

During 1821-1824 Sedgwick carried out researches in the north of England—on the Magnesian Limestone and New Red Sandstone and in the Lake District—but he delayed in the announcement and publication of his findings. Nevertheless, his standing in the world of science at that time and his general popularity were recognized by his being elected president of the Geological Society of London in 1829 and president of the British Association for the Advancement of Science in 1833.

In 1831 Sedgwick began the work which will always be associated with his name: the establishing of a rock-succession, the revealing of a grand structure among the mountains of North Wales, and the consequent founding of the Cambrian system. He did not put his researches into writing, and this was the chief cause of the regrettable controversy which eventually developed with Roderick Murchison over priorities of discovery and nomenclature among these Lower Paleozoic rocks (as they soon came to be called). However, Sedgwick did compose a few important treatises on the structure of rock-masses. In 1839 he and Murchison reported the results of their joint work which founded the Devonian system.

Thereafter Sedgwick's duties at his college and university caused his geological work, other than his lectures and the augmentation of his collections, to be almost entirely laid aside. Sedgwick never married. He died at Cambridge on Jan. 27, 1873. His lasting memorial is the Sedgwick Museum at Cambridge, opened in 1904, one of the most famous geological schools.

Sedgwick's reputation as a geologist and as a man rests almost entirely on his personality, which was conspicuous for its integrity, vigor, and charm, though he could be bitter in controversy. The influence of his presence and the power of his spoken word are not to be gathered from contemporary written records.

Further Reading

Sedgwick's A Discourse on the Studies of the University was recently reprinted with an introduction by Eric Ashby and Mary Anderson (1969), which focuses on Sedgwick's personality, his career as a teacher, and his efforts at educational reform. The standard biography is John Willis Clark and Thomas McKenny Hughes, The Life and Letters of the Reverend Adam Sedgwick (2 vols., 1890). Additional light is thrown on Sedgwick and his work in Sir Archibald Geikie, The Founders of Geology (1897; 2d ed. 1905), and Horace B. Woodward, The History of the Geological Society of London (1907). A good profile of Sedgwick is in Carroll Lane Fenton and Mildred Adams Fenton, Giants of Geology (1945; rev. ed. 1952).

Additional Sources

Speakman, Colin, Adam Sedgwick, geologist and dalesman, 1785-1873: a biography in twelve themes, Broad Oak, Heathfield, East Sussex: Broad Oak Press, 1982. □

type locality

views updated May 08 2018

type locality The particular site where the type section (stratotype) for a stratigraphic unit is located, or where the original type section was first described. Stratigraphic units normally take the geographic component of their name from that of the type locality, or a key physical feature there, e.g. the Kimmeridge Clay from Kimmeridge Bay in Dorset, England. Some early-defined stratigraphic units were named after the type area, e.g. the Cambrian System in Wales was named by Adam Sedgwick (1835) after Cambria, the latinized version of the Welsh cymry (‘fellow countryman’) and Cymru (Wales).

Sedgwick, Adam

views updated May 08 2018

Sedgwick, Adam (1785–1873) Woodwardian Professor of Geology at Cambridge, where he modernized the teaching of geology. He is best known for unravelling the stratigraphy of North Wales (the Cambrian System) which resulted in a quarrel with R. I. Murchison over the boundary between the Cambrian and Silurian Systems. He made important contributions to structural geology, distinguishing between stratification, jointing, and slaty cleavage.