The Edinburgh Geologist
Issue no 40

Edinburgh and the reception of early glacial theory

by Diarmid Finnegan


In reading through one of the several available histories of mid-nineteenth-century glaciology, certain people and places invariably appear - and for good reason. The first hints of the major conceptual innovation and theoretical shift that was early glacial theory are associated with the names of Swiss engineer Ignace Venetz, Swiss naturalist Jean de Charpentier, botanist Karl Schimper and, perhaps most of all, with Louis Agassiz.

Agassiz's conjecture that the surface of the earth had once been covered with ice from the North Pole to the Mediterranean and Caspian Seas during an epoch of intense cold was first announced in his Presidential address given to the Société Helvétique de Sciences Naturelles in Neuchâtel on 24th July 1837. Accounts of this famous episode in the history of the earth sciences track the development and fate of Agassiz's (and others) ideas to various destinations including, of course, Edinburgh. It is here that we encounter Robert Jameson, Professor of Natural History at the University, William Buckland and Roderick Murchison, prominent members of the London Geological Society, and other noted Edinburgh men of science including James David Forbes and Charles Maclaren. Edinburgh and its environs were thoroughly tramped over, from 1840 onwards, to establish an empirical warrant for or against the glacier theory. As Roderick Murchison put it, ' "Come and see" is the bold challenge of the Professor of Neuchâtel [Louis Agassiz] to all who oppose him' (Murchison 1842, p.686).

The land-ice theory of Agassiz and his most vociferous British supporter, William Buckland, remained one of several attempts to account for Britain's superficial deposits and contested geological markings for at least two decades before it became more widely accepted. Historians of geology, in order to indicate something of the theory's competitors, point to the influence of diluvialism and the perhaps more widely accepted floating iceberg theory. David Oldroyd (1999) has helpfully sketched an outline of these theories and points to certain variants including the diluvialist 'waves of translation' idea and the 'glacial submergence hypothesis' ('marinism'). Both of these hybrids had acquired, certainly by the 1850s, a certain amount of explanatory currency for British geologists. The somewhat later and incisive contributions of the Geikie brothers and James Croll helped bolster the status of, and transform, the land-ice hypothesis.

Although such historical accounts are worth pursuing in more detail, I want to change the pace and direction for this article. My own interest in the history of early glacial theory stems less from the point of view of a historian of geology strictly conceived. I am not nearly qualified to offer a 'what the early glacial theorists did for us' and have been more concerned in my work with 'popular' science than with the production of scientific theory. My efforts here involve highlighting some rather different but hopefully connected characters and concerns to those that appear in the standard accounts of the inception and early development of glacial theory. Rather than attempt to chart the theory's development through time, I spread my focus across Edinburgh's scientific culture (broadly conceived) as it presents itself in the 1840s. This reveals, I think, some intriguing work done by Edinburgh and Scottish 'unknowns' in relation to glacial theory as well as uncovering something of the wider scientific culture evident in mid-nineteenth-century Edinburgh.

Michael Taylor's recent articles in The Edinburgh Geologist have already signalled a number of the people and publications that feature here. Hugh Miller and his newspaper The Witness provide food for thought and Chambers's Edinburgh Journal makes an appearance. The part played by The Scotsman has been noted before in accounts of early glacial theory but it is worth re-visiting. Often cited in this regard is the letter from Louis Agassiz, dated 3rd October 1840 and first published in The Scotsman, announcing his recently acquired Scottish field evidence in support of previously existing glaciers; an occurrence often celebrated, perhaps unhelpfully, as a famous journalistic scoop. The series of detailed and original articles, published in January 1841, introducing The Scotsman's readers to glacial theory and penned by the geologist editor Charles Maclaren are also widely known. The pages of The Scotsman can be mined further, however, for other unfamiliar but still fascinating accounts of glacial theory. 

Before turning to these two newspapers and their editors, it is worth saying something about the engagement of Edinburgh's scientific societies with early glacial theory. By 1840, Edinburgh had a number of societies that interested themselves in geological matters. Although the Robert Jameson's Wernerian Natural History Society was in serious decline, there were a number of other more vibrant bodies. The Royal Society of Edinburgh (RSE) provided a formal space in which to present and debate papers on glacial theory. James David Forbes' work, at least for the RSE, concerned itself more with theories of glacier motion than with the larger claims of what he termed the glacier theory. It was the more eccentric Sir George Mackenzie, labelled rather brusquely by the zoologist Edward Forbes as a pseudo-geologist, who first aired Agassiz's ideas in the lecture hall of the RSE. His paper, entitled 'An attempt to reconcile the Theories of the Debacle and the Action of Glaciers, in accounting for the Distribution of Erratic Blocks' was, self-confessedly, a speculative affair.

Mackenzie's summing up suggested a volcanic eruption 'somewhere to the North West of the British Islands' had taken place in the 'Icy Sea' causing water and ice to flood over a submerged Britain and drop cargoes of gravel and boulders (Mackenzie 1841, p.435). Mackenzie gave some support to one of Agassiz's more familiar claims in a paper delivered a year later on the parallel roads in Glens of Lochaber. Agassiz attributed the existence of the parallel roads to a lake that had formed behind a glacier descending from Ben Nevis. Mackenzie, while differing with Agassiz on the reasons why a glacier might have previously existed in the area, supported the idea of an ice-dammed lake. A number of other RSE members tackled the subject of glaciers and glacial theory through the 1840s including James Stark, John Fleming and David Milne. Stark, an Edinburgh physician, concentrated on theories of glacial motion. Milne and Fleming both presented, on various occasions between 1846 and 1848, papers on geological markings around Edinburgh. Their lectures were characterised by a less speculative tone than the earlier presentations of Mackenzie. 

As readers of this magazine will know, the fledgling Edinburgh Geological Society (EGS) provided for its members a more informal debating space, meeting in Alexander Rose's home on the corner of South Bridge and Drummond Street. The EGS minute books reveal a cautious engagement with glacial theory summed up by the statement given by Alex Bryson in his paper on the subject that 'the Glacier theory of Agassiz is not applicable to Scotland at least in general' (EGS Minute Book No. II, 11 February 1841, underlined in original). Alex Bryson did not confine his presentation of glacial theory to the EGS, delivering a paper on glacial theory to a meeting in late March of the little known Cuvierian Natural History Society (Edinburgh Advertiser, 23 March 1841). The EGS continued its debates on glacial theory during 1841. James Brown (the Society's secretary) was noted as commenting on the longer history of the ideas promoted by Agassiz:

The theory which now is causing such enquiry among Geologists was advanced and discussed at a former period and though Agassiz may infuse into it something new yet the merits of the theory are not due to him. 

Brown's point reveals the willingness of the EGS members to question those who were accorded an elevated status in the geological world in a way that demonstrates the confidence the Society had in its ability to contribute to important theoretical debates. Further contributions were provoked on a number of occasions by discussions of Charles Maclaren's poplar introduction to glacial theory published in The Scotsman (and then in the form of a short book) although, sadly, little detail is given of what was said. 

If there was space, more could be said here about the cross currents between the survey work encouraged by the Highland and Agricultural Society of Scotland and glacial theory. The lecture series inaugurated by the Edinburgh Young Men's Society in 1842, which included a number of talks given by the theologian and populariser of science Thomas Dick, points to yet another context in which debate about glacial theory may have occurred (and certainly did in a similar lecture series given at that time in Glasgow). The Royal Physical Society of Edinburgh does not seem to have conspicuously debated glacial theory in the early 1840s although records are hard to come by for the Society at that time and its activities may have provided yet another arena for debate.

Edinburgh's institutional engagement with glacial theory in the 1840s provides just one context for re-discovering the sorts of early ideas that were circulated with regard to glacial theory beyond the more commonly cited examples. One of the more interesting mediums for someone interested in so-called popular science are the reports contained in the columns of Edinburgh's two best selling newspapers. Three leading articles, one from The Witness and two from The Scotsman, are especially revealing. 

On the 29th February 1840, just over a month after The Witness was launched, a leading article, authored by High Miller, appeared in its pages entitled 'The Chaotic Period'. The article was not about the chaos of contemporary church politics but instead outlined geological phenomena and theory that may have been 'alike new to the reader and are of very considerable importance' (The Witness, 29 February 1840). It narrated a week spent by 'a Scottish gentleman of very high attainment' with Louis Agassiz in the Swiss town of Neuchâtel. In the article Miller had Agassiz introduce to this Scotch geologist his conjectures regarding the work of glaciers and their former presence not only in areas of Switzerland now free of ice but across much of Europe. Miller's Scotch geologist can be identified as John Grant Malcolmson, correspondent of Darwin and member of the London Geological Society.

Malcolmson had returned from India in 1838, where he had served as surgeon for the Madras Medical Establishment, in order to complete his M.D. In 1839, on arriving back from his trip to Switzerland, Malcolmson spent time examining the superficial deposits and rock surfaces of Scotland to see if Agassiz's theory applied to Scotland. In a letter to Darwin, Malcolmson exclaimed that he 'found a little north of Pettycur in Fifeshire, the sandstones having grooved and polished surfaces exactly like the limestone of Neuchâtel' (Burkhardt et al. 1985, - emphasis in original). Despite this evidence, Malcolmson remained cautious about the adequacy of Agassiz' theory in explaining the erratics and drift of Scotland. Although Miller echoed such caution in his article, its 'condensed and popular' presentation of Agassiz's ideas was remarkably enthusiastic in tone. Far from threatening the biblical accounts of creation, Agassiz's 'chaotic period' resonated for Miller with the death and darkness alluded to in the second verse of Genesis. Glacial theory had, potentially at least, scientific and theological warrant.

A number of interesting observations can be made about Miller's piece. The article pre-dates by some seven months the famed announcement in 1840 by Agassiz at the September meeting of the British Association for the Advancement of Science (BA) in Glasgow. Agassiz's ideas had already appeared in Edinburgh thanks to the editorial work of Robert Jameson and his nephew Thomas Torrie. Arguably, however, Miller's piece was the first to bring Agassiz's ideas to a wider and more popular readership than that of Jameson's journal (Edinburgh New Philosophical Journal). Even after the BA meeting, none of the Edinburgh or Glasgow newspapers appear to have reported Agassiz's claims that glaciation may have extended to Scotland. Chambers's Edinburgh Journal, edited by Robert Chamber, did report such claims some time later and noted that Section C (geology) meeting at which Agassiz gave his address not only attracted the largest audience but also 'the greatest proportion of ladies' (Chambers's Edinburgh Journal, 14 November 1840). Miller's piece, however, had given more detail and had pre-empted the popular reportage of Agassiz's public announcement in Glasgow.

The combination of geological and theological concerns presented by Miller was characteristic of all his writings on geology. This sort of mixing does not seem to mean, as some have implied (see, for example, G. Rosie 1981), that Miller was slower to accept glacial theory because of his religious sensibilities. It is true that Miller did not accept Agassiz's idea of an ice sheet, at least in his later geological writings, preferring to appeal to a combination floating icebergs and glaciers. This was in line with a good number of geologists at that time and usually had nothing to do with espousing a biblical deluge (which Miller, as Michael Taylor pointed out, considered a local event). Miller's early article was willing to countenance Agassiz's land-ice theory as a potentially revolutionary move in geological thought and Miller appeared eager to accept it if the evidence so allowed. 

Miller's theological appraisals are an aspect of the debates about glacial theory altogether lacking in accounts given by Charles Maclaren of the Scotsman. Maclaren was actively involved in the more elite geological circles of Edinburgh and Britain. A former student of Alexander Rose and Robert Jameson, his 1839 book, The Geology of Fife and the Lothians, was widely acclaimed. He participated in the famous October 1840 excursions around Edinburgh that involved, among others, Buckland and Murchison and, two days later, Louis Agassiz himself.

I have already highlighted some of better-known contributions of Maclaren and The Scotsman to discussions on glacial theory. There are, as I suggested, some other unfamiliar articles that make fascinating reading. Two in particular, written by the same person and introduced by Maclaren, are particularly remarkable. The first, despite being 'scarcely adapted for the pages of a newspaper', appeared during the Parliamentary vacation of 1841/42 when 'few stories were stirring'. It was authored by John Dove of Glasgow (about whom I have been able to find out nothing) and concerned itself with establishing astronomical causes for the build up of ice and a vastly increased degree of cold in the extra-tropical regions. These causes, Dove argued, had been established years before the glacier theory had been thought of.

Drawing on the treatise on astronomy by Sir John Herschel in Encyclopaedia Britannica Dove pointed out that the ever-reducing obliquity of the ecliptic or the diminishing 'angles formed by the planes of the equator and the ecliptic' meant that in the past, when the angle was greater, 'an universal winding-sheet snow and ice' could accumulate in the winters of the two hemispheres and would produce 'an universal flux in the course of each summer' (The Scotsman, 5 January 1842). In addition to the obliquity of the ecliptic Dove also pointed out the astronomical hypothesis which suggested changes in ellipticity of the earth's orbit would mean that for 'myriads of years' the earth may have had much more pronounced seasonality and for a further long period of time the earth would experience 'a perpetual spring'. Dove pointed out that the eccentricity of the earth's orbit could move from a pronounced ellipse to a purely circular motion and back to occupying an eccentric path. Dove continued his line of reasoning about the obliquity of the ecliptic in his sequel article where he sought to expand his thinking on the extent to which the axial tilt of the earth, and other planets, changes through time. Maclaren introduced Dove's second article, which was less concerned with glaciation and more with astronomy, by giving a more popular summary of what was 'an abstruse subject. ill suited to readers of a newspaper.' 

Dove's accounts offer if not the earliest published attempt to give an astronomical explanation of Agassiz's ideas, at least one of them. I have not been able to establish whether James Croll knew of Dove's articles but they certainly seem to deserve a place in a history of astronomical explanations for the ice age. Often cited in this regard is the French astronomer Joseph Adhémar's book Révolutions de la Mer, also published in 1842, which linked the precession of the equinoxes with the accumulation of ice in which ever hemisphere received less insolation. (see Imbrie and Imbrie 1979). That Dove's arguably more ingenious attempts appeared in the pages of a best selling Edinburgh newspaper tells us something about the difficulty of drawing, at that time at least, a clear boundary between popular and 'proper' science. 

Browsing through early Victorian Edinburgh newspapers and popular monthlies, the reports of popular educational bodies, the science journals and the proceedings of the more obviously scientifically engaged societies reveals a complex web of connections and disjuncture in the promotion and reception of early glacial theory in and beyond the City. No doubt, much of the real geological work was reported in the pages of the Edinburgh New Philosophical Journal and accomplished though the fieldwork of the more expert geologists but glimpses of serious effort can be seen in arenas that we would consider more popular. The ways in which a range of people responded to glacial theory can be of as much interest as accounting for how the 'theory itself' was constituted, refined and disputed. It is surprisingly difficult, however, viewed in the context of mid-nineteenth-century Edinburgh's scientific culture, to entirely separate out the theory's makers, promoters and consumers. Endeavouring to do this can throw out one or two accounts that may constitute hitherto unrecognised additions to our bigger picture explanations of the making of glacial theory. 

References and further reading

Boylan, P. J. 1998. 'English and Scottish Glacial Localities of Agassiz, Buckland and Lyell, 1840', British Library/Geological Society of London supplementary publication. Available online,

Burkhardt, F. H. et al. 1985. The Correspondence of Charles Darwin [Vol. 2.]. Cambridge University Press.

Cunningham, F. F. 1990. James David Forbes. Pioneer Scottish Glaciologist. Edinburgh: Scottish Academic Press. 

Herries Davies, G. L. 1969. The Earth in Decay. A history of British geomorphology, 1578-1878. Macdonald & Co.

Murchison, R. I. 1842. 'Anniversary Address of the President'. Proceedings of the Geological Society of London, Vol. 3, pp. 635 - 687.

Oldroyd, D. R. 1999. 'Early Ideas About Glaciation in the English Lake District: The Problem of Making Sense of Glaciation in a Glaciated Region.' Annals of Science, Vol. 56, pp. 175-203.

Rosie, G. 1981. Hugh Miller: outrage and order: a biography and selected writings. Mainstream.


Figure 1 Forbes engraving

Engraving of glaciologists in the field. Taken from  Travels through the Alps of Savoy by J.D. Forbes

Figure 2 Engraving  of Aletsch Glacier

Engraving from 1900 of a panoramic view from the top of the Eggishorn, showing the Aletsch Glacier, Märjelen and Fiesch Glacier. At the end of the nineteenth century the Aletsch Glacier was 3 kilometres longer than today. Engraving published courtesy of Michel Azéma from whose web site this image was taken.

Figure 1inscription in author's copy of Heddle

Portraits of Charles Maclaren (left) and Hugh Miller (right). Maclaren's portrait appeared in Cox, R. & Nicol, J. 1969. Selected Writings of the late C. Maclaren. Miller's is by Bell after a photograph by Tunny, photo Suzie Stevenson, courtesy and copyright of the Trustees of the National Museums of Scotland.

Diarmid Finnegan is a postgraduate student in Geography, School of Geosciences, University of Edinburgh. His doctorate research is centred on Scottish natural history societies in the nineteenth century.

This article is based on an unpublished Edinburgh University MRes thesis by Diarmid Finnegan entitled A historical geography of glacial theory in early nineteenth century Edinburgh. The Author acknowlwedges the help given to him in the preparation of this paper by Professor Charles Withers and Dr. Michael Taylor.

The illustration of the Swiss glaciers is by permission of Michel Azéma from whose web site the image was taken. This and other images of these glaciers are to be found on

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