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Lyell and the Dilemma of Quaternary Glaciation

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Lyell and the Dilemma of Quaternary Glaciation Downloaded from http://sp.lyellcollection.org/ by guest on September 25, 2021 Lyell and the dilemma of Quaternary glaciation PATRICK J. BOYLAN City University, Frobisher Crescent, London EC2Y 8HB, UK Abstract: The glacial theory as proposed by Louis Agassiz in 1837 was introduced to the British Isles in the autumn of 1840 by Agassiz and his Oxford mentor, William Buckland. Charles Lyell was quickly converted in the course of a short period of intensive fieldwork with Buckland in and around Forfarshire, Scotland, centred on the Lyell family's estate at Kinnordy. Agassiz, Buckland and Lyell presented substantial interrelated papers demonstrating that there had been a recent land-based glaciation of large areas of Scotland, Ireland and northern England- at three successive fortnightly meetings of the Geological Society of London, of which Buckland was then President, in November and December 1840. However, the response of the leading figures of British geology was overwhelmingly hostile. Within six months Lyell had withdrawn his paper and it had become clear that the Council of the Society was unwilling to publish the papers, even though they were by three of the Society's most distinguished figures. Lyell reverted to his earlier interpretation of attributing deposits such as tills, gravels and sands and the transport of erratics to a very recent deep submergence with floating icebergs, maintaining this essentially 'catastrophist' interpretation through to his death a quarter of a century later. Many paradigm shifts in the development of Agassiz and his 'Discours de Neuch~tel' presi- science (Kuhn 1960) have depended less on a dential address (1837) presenting the theory of a major, unexpected intellectual leap on the part of very recent major ice age to the SociEt6 Hrlvrtique some heroic scientific figure than on the sudden des Sciences Naturelles (Agassiz 1837, 1838). recognition of a new interpretation of well estab- However, though Agassiz was certainly of great lished evidence: re-examining and reinterpreting importance, this is a major oversimplification. perhaps very well established facts and obser- From at least the late 1820s there had been growing vations within a new theoretical framework. In the speculation about the possible role of a recent context of the Pleistocene this is now widely major land glaciation in processes of erosion, recognized to be the case, particularly since the transport and deposition across much of the now publication of the wide-ranging Ice Ages: Solving temperate regions of the northern hemisphere. As is the Mystery by Imbrie and Imbrie (1979). The well known, more than a generation earlier both central theme of the present paper is the response of Hutton and Playfair had speculated on this Charles Lyell (1797-1875) to the reinterpretation in possibility. the autumn of 1840 by Louis Agassiz (1807-1873) In 1826 Robert Jameson published in his and Lyell's former teacher and mentor William Edinburgh New Philosophical Journal a translation Buckland (1784-1856) that much of the well from the original Norwegian of a paper by the known 'superficial' deposits of northern Britain Dane, Jens Esmark, arguing that both Norway and were evidence of a Recent land-based ice age. In Denmark had been recently glaciated (Esmark Lyell's case, following his conversion to the glacial 1826). Furthermore, Herries Davies has shown theory, he drew some of his strongest evidence for from both the recollections of J. D. Forbes and a Recent glaciation from field work that had notes in the Jameson Papers in Edinburgh that by featured in his first communication to the 1827 Jameson was discussing the former existence Geological Society 14 years earlier (Lyell 1826), of glaciers in Scotland in his university lectures while Buckland similarly reinterpreted a wide (Davies 1969, pp. 267-270.) range of observations made up to 29 years earlier However, the 1837 'Discours' of Agassiz was (Buckland 1841, p. 332). certainly a key event, not least because of its indirect impact in Britain. A number of leading British scientists had been amongst the first to The discoveries of Agassiz recognize the remarkable abilities of the 29-year- In regard to the recognition of glaciation, the old old Agassiz as a vertebrate palaeontologist, and 'heroic' view of geological progress focused on the British patrons and organizations (particularly the brilliant young Swiss palaeontologist, Louis Geological Society) were important sources of BOYLAN, P. J. 1998. Lyell and the dilemma of Quaternary glaciation. In: BLUNDELL,D. J. & 145 Sco'rr, A. C. (eds) Lyell: the Past is the Key to the Present. Geological Society, London, Special Publications, 143, 145-159. Downloaded from http://sp.lyellcollection.org/ by guest on September 25, 2021 146 R J. BOYLAN Agassiz's income from 1834 onwards through their possible. However, interest in the new glacial funding of his work on British fossil fish collec- theory was growing. Perhaps most significantly of tions. It was therefore with much alarm that his all, Agassiz's 'Discours de Neuchfitel' was within a leading British patrons and supporters, above all matter of months plucked from the relative Buckland, once regarded as an arch-catastrophist obscurity and limited circulation of its original himself, learned of Agassiz's sudden espousal and publication in the Actes de la Soci~t~ Hdlvdtique exposition of the glacial theory in July 1837 (Agassiz 1837) and given worldwide circulation in (Agassiz 1886, pp. 248-251). English translation by Robert Jameson of the As early as 1831 Buckland himself had argued University of Edinburgh in Jameson's influential that the 'northern region of the earth seems to have Edinburgh New Philosophical Journal (Agassiz undergone successive changes from heat to cold' 1838). (Significantly, Jameson translated and (Buckland 1831). However, geological deposits of republished four other substantial Continental this last period of intense cold continued to be publications on the glacial theory between 1836 interpreted in terms of aqueous deposition, whether and 1839.) through catastrophic flooding events (in Lyell was by this time well aware that there had Buckland's case) or the gentle marine submergence been one or more geologically recent cold phases, of Lyell. Buckland saw the heterodox views of the as demonstrated by the 'Arctic' molluscan faunas 'Discours' as representing a potentially serious that were being widely recognized in the Newer threat to further British support for Agassiz's highly Pliocene (soon to be renamed Pleistocene) of important vertebrate palaeontology work, and temperate latitudes, and hence he was moving resolved to visit Switzerland himself in order to towards the acceptance of a glacial phase, at least in dissuade Agassiz from pursuing his glacial theory climatic terms. However, he was fundamentally any further. opposed to Agassiz's inferred mechanism of a con- Another important patron, Alexander yon tinental scale glaciation to explain the characteristic Humboldt, gave the same advice in a letter of 2 features of erosion, transportation and deposition, December 1837: and therefore prepared a major paper intended to refute the emerging glacial theory. He avoided a I am afraid you work too much, and (shall I tell frontal attack: within the accepted traditions of the you frankly?) that you spread your intellect over Geological Society this would have been regarded too many subjects at once. I think that you should as just as 'unphilosophical' as the glacial heresy concentrate your moral and also your pecuniary itself (see, for example, Rudwick 1963; Morrell strength upon this beautiful work on fossil 1976; Thackray this volume). Instead, Lyell care- fishes .... In accepting considerable sums from fully followed the Geological Society's tradition, England, you have, so to speak, contracted and in 1839 presented to the Society an apparently obligations to be met only by completing a work innocuous descriptive paper on the thick and which will be at once a monument to your own extensive superficial deposits that are so abundant glory and a landmark in the history of science ..... in the glaciated areas of eastern England. under the No more ice, not much of echinoderms, plenty of title 'On the Boulder Formation or drift and fish... (Agassiz 1886, pp. 267-272). associated freshwater mud cliffs of eastern Because of Buckland's heavy teaching and Norfolk' (Lyell 1840). In this, Lyell described in religious duties at Oxford, his first opportunity to some detail a wide range of features including the visit Agassiz in Neuchatel was the 1838 summer very typical boulder clays, erratic boulders trans- vacation. He remained at first 'an uncompromising ported from long distances including some almost opponent' of the glacial theory (Gordon 1894, pp. certainly transported all the way from Scandinavia, 140-141) and pleaded with Agassiz to recant. freshwater Arctic shell horizons and apparently However, by the end of his Swiss tour Buckland near-contemporaneous contortions in deposits. appears to have been not only converted to Lyell accepted the evidence for a recent very cold Agassiz's argument that the Alps and adjacent phase, but attributed the actual deposition of the lowlands had been extensively glaciated in geo- boulder clay and erratic blocks and boulders to a logically recent times, but also realized that he was phase of relatively deep submergence, with long- observing unmistakable parallels to localities in distance transport by icebergs, the grounding of Scotland
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