5A. AGASSIZ IN BRITAIN, 1840: THE SCOTTISH TOUR
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"Shall we be obliged, by assigning the same causes to the same effects, to believe that the former extension of our glaciers was much beyond the most advanced limits they now attain; or rather that a covering of ice had enveloped the whole of the terrestrial globe, if it be true that the same phenomenon likewise appears in Sweden, England, and other countries very remote from high mountains ?" (Studer, 1840)
"After having obtained in Switzerland the most conclusive proofs, that at a former period the glaciers were of much greater extent than at present, nay, that they had covered the whole country, and had transported the erratic blocks to the places where these are now found, it was my wish to examine a country where glaciers are no longer met with, but in which they might formerly have existed. I therefore directed my attention to Scotland . . . (Agassiz Letter to The Scotsman newspaper, October 6, 1840)
"If the analogy of the facts which he has observed in Scotland, Ireland, and the north of England, with those in Switzerland, be correct, then it must be admitted that not only glaciers once existed in the British Islands, but that large sheets (nappes) of ice covered all the surface." (Agassiz, 1840)
Moraine ridge of the Nithsdale
Valley glacier, near Thornhill, Dumfrieshire, Scotland:
". . . visited
independently by Buckland a few days before the opening of the British
Association Meeting on 18th September 1840 . . . probably ranks as the first
glacial locality to be fully recognized and understood in Britain." (Boylan,
1981)
(http://www.grisda.org/origins/09028.htm)
Water (global or regional inundations, tsunami), ice-floes, glaciers, ice dams and debris flows -- all were candidate explanations for: erratics, boulder-clay, polished-striated-grooved rocks, roches moutonees, moraine ridges, and Brongniart’s “ase” ridges. In addition, Esmark had suggested glacial erosion as a process in valley formation.
In his "Discours de Neuchatel," Agassiz (1837) argued that only a glacial theory could account for all these features at one and the same time, as no other theory could (Renoir made the same point in 1839/1840): “If this theory be correct, and the facility with which it explains so many phenomena which have hitherto been deemed inexplicable, induces me to believe that it is; then it must follow that there has been, at the epoch which preceded the elevation of the Alps and the appearance of the existing animated world, a fall of temperature far below that which prevails in our days” (Agassiz 1837, p.377). All that was required was to accept that there had existed a colder period in Earth’s recent past, and this he argued for on the basis of the fossil record (e.g. Cuvier’s frozen mammoths).
In 1840 Agassiz was again in Britain to study and report on fish fossils, and he gave a paper at the British Association for the Advancement of Science Annual Meeting in Glasgow “On the Glaciers and Boulders of Switzerland.” But if Agassiz was correct about a major continental ice sheet then he also had to prove that evidence for its existence was equally widespread. In fact Renoir had already contributed to this in the Vosges, and Agassiz had enlisted, second-hand, observations from Sefstrom and Brongniart in Sweden, among others, in support of his idea.
In his 1840 “Etudes sur les glaciers,” which he brought Scotland with him, Agassiz referenced the work done in the Vosges by Renoir and others and used that work to suggest that elevation of the Alps was an unnecessary component of Charpentier's more limited regional theory. He noted that evidence of glaciation from the Vosges lent support to idea of an Ice Age and he referenced Brongniart's and Sefstrom’s observations in Sweden as evidence in support of this hypothesis of widespread glaciation: "I am convinced that the hypothesis of great glaciers, related to the polar ice advancing from northern Scandinavia toward the continental plain, would better account for the formation and orientation of these striations than Sefstroem's great universal current, or any other current . . . This huge mass of ice, moving continuously over the ground in the direction of the slope, must have . . . polished the rocky surfaces" (Agassiz 1840 p.303, 305).
Having laid before the Association a copy of the plates from his new book “Etudes sur les Glaciers,” he then set off into the Highlands with William Buckland with the express intent of finding this evidence for himself and his "tour" elicited widespread interest in the popular imagination: “Professor Agassiz is also inclined to suppose that glaciers have been spread over Scotland, and have every where produced similar results. If we understood him rightly, he means to follow up his valuable researches in the Highlands of Scotland during his stay in this country, where he confidently expects to find evidence of such glaciers having existed” (The Scotsman, 1840).
Agassiz sent a letter to William Jameson from the trip and The Scotsman Newspaper published it under the headline: “Discovery of the Former Existence of Glaciers in Scotland, especially in the Highlands, by Professor Agassiz.”
"Extract from a letter from Professor Agassiz to Professor Jameson . . . I discovered the most distinct morains [sic] and polished rocky surfaces, just as in the valleys of the Swiss Alps, in the region of existing glaciers; so that the existence of glaciers in Scotland at early periods can no longer be doubted.” He continued: “The parallel roads of Glen Roy are intimately connected with this former occurrence of glaciers, and have been caused by a glacier from Ben Nevis. The phenomenon must have been precisely analogous to the glacier-lakes of the Tyrol, and to the event that took place in the valley of Bagne. It appeared to me that you would be glad to be able to announce, for the first time, in your extensively read journal, the intelligence of the discovery of so important a geological fact.”
William Buckland wrote in delight to a friend: "We have found abundant Traces of Glaciers round Ben Nevis" (White 1970).
Buckland met up with Charles Lyell on the Lyell family’s estate in Forfarshire and Lyell reinterpreted various features in the area as being of glacial origin.
In 1842 Agassiz summed up progress in a paper in which he also published his reinterpretation of the Parallel Roads of Glen Roy. However, prior to that, he visited the Geological Society in London to give a paper along with Lyell and Buckland detailing their interpretations at various locations, as arranged by the Society’s President, Buckland.
Agassiz mapped the Parallel Roads (left) and showed how “Supposed prolongations of the Glaciers of Taconay and de Bois” (two Mont Blanc Massif glaciers) could produce a similar effect in the valley of Chamonix (River Avre) to the one he proposed to solve the puzzle of the barriers that ultimately had been responsible for the Parallel Roads (i.e. “Supposed Glaciers” in the valleys of Ben Nevis and Loch Treig). Note how he also addressed Darwin's question of striae (see "Glen Roy Revisited" Episode). (Agassiz 1842, p.239, 427).
REFERENCES
Agassiz, L. 1840 Etudes sur les glaciers (Agassiz, Jent & Glassmann, Neuchatel) http://books.google.com/books?id=fTMAAAAAQAAJ
TRANSLATION: Carozzi, A.V. (trans) 1967 Studies on glaciers preceded by the Discourse of Neuchatel by Louis Agassiz (Hafner Publishing Company, New York and London)
Agassiz, L. 1840 Glaciers, and the evidence of their having once existed in Scotland, Ireland, and England. Proceedings of The Geological Society of London v.III (Nov. 1838 to June 1842), Part II (1840-1841), no.72 p.327-332
http://www.google.com/books?id=giPPAAAAMAAJ&pg=PA327
Agassiz, L. 1842 The glacial Theory and its recent progress. The Edinburgh New Philosophical Journal v.33 (April – October 1842) p.271-283, plate p.427 http://books.google.com/books?id=lRMAAAAAMAAJ&pg=RA1-PA217
Boylan, P.J. 1981 The role of William Buckland (1784-1856) in the recognition of glaciations in great Britain. p.1-8 in J. Neale and J. Flenley (eds.) The Quaternary in Great Britain (Pergamon Press, Oxford)
Boylan, P.J. 1998 Lyell and the dilemma of Quaternary glaciation. p.145-159 in D.J. Blundell, S.C. Scott (eds.) Lyell: the past is the key to the present The Geological Society, London, Special Publication 143 (GSL, London) http://sp.lyellcollection.org/cgi/reprint/143/1/145.pdf
Davies, G.L. 1968 The tour of the British Isles made by Louis Agassiz in 1840. Annals of Science, v.24 (2) p.131 – 146
Finnegan, D.A. 2004 The work of ice: glacial theory and scientific culture in early Victorian Edinburgh. British Journal for the History of Science v.37(1) p.29-52
Gordon, Mrs. 1894 The life and correspondence of William Buckland D.D., F.R.S. (D. Appleton and Company, New York) http://www.google.com/books?id=bgMqAAAAYAAJ&pg=PR3
The Scotsman Newspaper 1840 Discovery of former glaciers in Scotland, especially in the highlands by Professor Agassiz. The Literary Gazette; and Journal of Belles Lettres, Arts, Sciences &c. for the year 1840, p.671
http://books.google.com/books?id=ty6lmkjZr9QC&pg=PA671
White, G.W. 1970 Early Discoverers XXVII: Announcement of glaciations in Scotland: William Buckland (1784-1856). Journal of Glaciology v.9(55) p.143-145
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Thomas
Sopwith’s cartoon of William Buckland as a convert to the glacial theory
("Scratched by T. Sopwith"): “COSTUME of the GLACIERS.” The carriage in the
background perhaps makes reference to his Scottish Tour with Agassiz, or perhaps
to the trip he took with Sopwith to Betws y Coed in Wales in 1841. The map case
states: “Maps of ancient glaciers.” Front plaque: “The Rectilinear Course of
these Grooves corresponds with the motions of an IMMENSE BODY the momentum of
which does not allow it to change its course upon Slight Resistances.” Bottom
right: “Prodigious Glacial Scratches” and “Scratched by T. Sopwith.” The
striated rock in the rear lower left: “Specimen No1. Scratched by a glacier
Thirty three Thousand Three hundred & Thirty Three years before the Creation.”
The rock in front states “Scratched by a cart wheel on Waterloo Bridge the day
before yesterday.” (Gordon 1894, facing p.145)
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