Earth in Upheaval Revisited – Part 10

A Glacial Erratic in Jökulsárlón, Iceland

“Icebergs” is the third section of Chapter III in Immanuel Velikovsky’s Earth in Upheaval. In this brief section—it occupies little more than a single page of the book—Velikovsky glances at Charles Lyell’s theory that drifting icebergs were responsible for the erratic boulders that are found strewn across the North European Plain.

The theory that rejected the occurrence of catastrophic events in the past was incompatible with the then prevailing teaching, which ascribed the distribution of drift (the deposit of rock debris, clay, and organic material that covers continental areas) and of erratic boulders to the action of water in the form of great tidal waves breaking upon the continents. A slow-moving source, able to do the same work, but in a longer time, had to be found. Lyell assumed that icebergs transferred rocks over the expanse of the sea. Icebergs are broken-off parts of glaciers that descend from the mountainous coasts to the sea. Mariners in northern waters have observed icebergs with pieces of rock attached to them. And if we think of the enormity of past geological epochs and multiply the action of icebergs as carriers of earth and rocks by the time elapsed, we may explain, so argued Lyell, the presence of erratic boulders as well as of till and gravel on land. (Velikovsky 27-28)

The Iceberg, or Drift, Theory was first proposed in 1742 by the Swedish mineralogist Daniel Tilas, almost half a century before the Swiss geologist Horace-Bénédict de Saussure drew the attention of the scientific community to the existence of erratic boulders. As we saw in an earlier article in this series—The Erratic Boulders—Saussure observed that the southern slopes of the Jura Mountains were strewn with rocks and boulders of Alpine origin. :

Horace-Bénédict de Saussure

§206 ... one cannot but recognize that these fragments were not formed in this valley, or on the surrounding mountains; but that they are foreign bodies, adventitious, torn from the Alps, their native land, by a powerful agent, which has transported them, rounded their surfaces and piled them up in confusion. (Saussure 201-202)

§207: That water was this agent cannot in the least be doubted; because these stones, both large and small, are found deposited on horizontal ridges, mixed with sand and gravel, just as water transports them. For if one sees one of these fragments exposed on a rock, inspection of the site alone clearly demonstrates that rainwater or meltwater has carried off the lightest pieces, which formerly surrounded these large masses. (Saussure 202)

Long before Saussure, however, German and Scandinavian writers had addressed the mystery of the erratics, or Findlinge—“orphans”—as they called them. The story of erratics and their role in geology is richer than I had suspected when I wrote that earlier article. In fact, Saussure was not even the first to suggest that the erratics had been transported to their final resting places by water:

Erratic blocks in the alpine region and the northern European lowlands have attracted people’s attention for thousands of years. In the neolithic Age, between about 5500 and 2000 BC, the inhabitants of these regions turned Findlinge—pieces of rock “orphaned” from their parent beds—into places of worship and used them to build megalithic tombs ...

An Erratic on the Danish Island of Bornholm

References to often very remarkable erratic boulders are found in medieval writings. The Danish historian Saxo Grammaticus (1150–1220) reported about constructions out of huge orphaned blocks around 1200, which he interpreted as the work of giants. The oldest written mention of a Findling from the region of the Alps probably appears in a deed dated to the year 1301 ... The first unquestionable written mention of an erratic block is in Johannes Guler’s (1562–1637) work Raetia, which appeared in Zürich in 1616. In it he mentions a “Coloss” in the Valtellina valley in the Italian Alps, about which he could not see “whence it might have split.” ... The town clerk of Lucerne, on the other hand, one Karl Nicolaus Lang (1670–1741), wrote at greater length about erratics, just short of a century later, in his Historia naturalis, which appeared in 1708. He seems to have suspected a connection between the erosion of alpine peaks and the dispersal of such blocks ... The city physician of Lucerne Moritz Anton Capeller (1685–1769) recognized the alpine origin of erratic blocks in the Swiss Prealps in 1727/28. In his work published forty years later, Pilati montis historia, he attributed their dispersal “to the deluges of floods.” The Bernese notary Abraham Schellhammer (1675–1735) expressed a similar thought. He blamed the distribution of such orphaned rocks on the biblical flood, in his Topographia from 1732. He was evidently aware of their alpine origins because he wrote that they came from the “destruction of the mountains.” (Krüger 23-24)

Daniel Tilas

Although Tilas was the originator of the Iceberg Theory, he was actually more inclined to Catastrophism than to Uniformitarianism:

In April 1742 the Swedish mineralogist and mining expert Daniel Tilas (1712–1772) presented a report about the origins of erratic blocks before the Swedish Academy of Sciences. He thought Findlinge were relics of Noah’s flood. He considered it possible, however, that floating pieces of ice had carried them over from polar regions and dropped them upon melting. Tilas was thus presumably the first to have put to paper the notion of drifted erratic material. (Krüger 38)

And that is where things stood when Charles Lyell entered the field.

Lyell’s Shifting Opinion

Lyell had the opportunity to examine numerous erratic boulders during an extended trip to Denmark and Sweden in 1834 and 1835. On 30 June 1834, he made the following entry in his journal:

I have got a date for some of the largest erratic blocks, and shall quite overset the débacle theory, and I expect to bring in ice-carriage as the cause. (Lyell 1:432)

The Débâcle Theory is an old name for the Diluvial Theory, which attributed the deposition of the erratics to catastrophic floodwaters—originally identified as the waters of Noah’s Flood:

With its origin in the mid-eighteenth century the iceberg theory may be claimed as the first glacial theory ... Initially it provided merely a means for explaining the occurrence of erratics, objects whose location far from the rocks from which they were derived had long puzzled geologists. These had been explained as due to the deluge of Noah, to a sudden ‛debacle’—or great wave—resulting from a submarine seismic uplift ... The ‛Diluvial’ school attributed all such phenomena to the action of water alone, though not necessarily in the form of the Noachian flood. (Mills 110)

Charles Lyell

In July of 1834, Lyell wrote a letter from Stockholm to his father-in-law, the Scottish geologist Leonard Horner, in which he briefly discussed the erratic boulders:

Another line of research has been the huge drift blocks, or Baltic boulders or ‛erratic blocks,’ which cover all Denmark and Sweden. Their size is often enormous. Some I have ascertained have been placed where they are in times exceedingly modern, geologically speaking, certainly late in Newer Pliocene period. I believe that ice has brought them. I have questioned the pilots closely about the agency of ice, in which they believe. I am persuaded that ice can do much for us. (Lyell 1:437)

In a later letter, however, written in London on 25 October 1835 and addressed to Adam Sedgwick, Woodwardian Professor of Geology at Cambridge, Lyell expressed doubts for the first time about the ability of icebergs to transport the largest of the erratics:

As to erratic blocks, I have no positive general theory, but after seeing Sweden, I cannot for a moment believe they are due to diluvial action. I saw none in Italy, Spain, or Sicily, a few in the Jura and Alps, hundreds in Denmark, thousands everywhere in Sweden, and of stupendous size. It seems to me a northern phenomenon when best developed. Ice does annually carry large stones on Lake Wener, and in the Gulf of Bothnia, not so big as cathedrals I grant, but tolerable sized pebbles, such as many men could not move.

But I must return to this when we meet, only remember that icebergs float now much farther south than the Jura. (Lyell 1:459)

The Runkesten (Rocking Stone), An Erratic in Småland, Sweden

As the nineteenth century wore on, Catastrophism was gradually eclipsed by Uniformitarianism in the halls of Academia. The debate was no longer a contest between these polar opposites, but rather a question of which of the competing Uniformitarian theories ought to be accepted.

[The Diluvial] school soon lost ground. The debate then became focussed on the role of ice, between the ‛land ice’, or glacier, school, whose most eloquent advocate was Agassiz, and the ‛sea ice’, or iceberg, school. (Mills 110)

The mechanism associated with the Iceberg Theory actually came to be called the Lyell Drift, but more than twenty years after he first endorsed this theory, Lyell announced that he was now more inclined to accept the Glacier Theory. In a letter from Zürich to his father-in-law, dated 16 August 1857, he wrote:

The most striking phenomenon in these large quarries at Soleure was an extensive shelf of the limestone, from which a covering of about eight feet of solid unstratified mud, full of angular and subangular boulders, had just been removed. These boulders, with now and then a block large enough to be called an erratic among them, were many of them striated, polished, and scratched on one or on all sides ... The erratics here are part of the supposed doings of Charpentier’s great glacier, which walked across the great valley of Switzerland from Monts Blanc and Bosa to the Jura, with a thickness of ice of some 4,000 feet [1200 m], then abutting against the limestone chain, and rising nearly to its culminating ridge spread itself on each side, after leaving Pierre-à-Bot (the toad stone) above Neuchatel, and some still more enormous angular masses on the cretaceous and oolitic rocks of the Secondary Chain.

Pierrabot, An Erratic above Neuchâtel, Switzerland

In order to escape from the necessity of appealing to such a gigantic mound of ice, I ventured, you may remember, to suggest that the sea may have floated the Alpine erratics to the Jura, as Darwin has shown that the ocean now carries on ice rafts the rocks of the Andes to [Chile], arranging them there with no small regularity. But the entire absence of marine remains in the associated gravel, mud, and moraine, whether here or anywhere in Switzerland, the conformity of the distribution of the travelled blocks here with the shape of so many valleys, and above all, the sight of the Alpine snows at Berne and elsewhere, has made me strongly incline, with Charpentier, Agassiz, and others, to embrace (as James Forbes did) the theory of a terrestrial glacier. (Lyell 2:249-250)

This change of heart removes an inconsistency that Velikovsky raises:

Erratic boulders are found far from the seashore: Lyell taught that the land was submerged and icebergs traveling over it dropped their load of stones; later the land emerged with the stones on it. Erratic boulders are found on the mountains; therefore, these mountains were under shallow water when icebergs carrying stones from other regions dropped them on the summits. In order to explain in this manner the provenience of erratic boulders, it was necessary to submerge large parts of continents in rather recent times. (Velikovsky 28)

The Richmond Boulder Trains in the Berkshires

Strings of Erratics

Velikovsky briefly raises another problem, as he saw it, with the Iceberg Theory:

In some places erratic boulders are distributed in a long string—as in the Berkshires. Icebergs could not have acted as intelligent carriers, and Lyell must have felt the weakness of his theory on this point. The only alternative known at that time was that of a tidal wave. (Velikovsky 28)

The Berkshires is a mountainous tract of western Massachusetts and northwestern Connecticut. Velikovsky does not cite any source for this long string of erratics. In the previous section, The Hippopotamus, he quoted Henry Williamson Haynes & George Frederick Wright’s Man and the Glacial Period without crediting it. It is possible that this was his source for the trains of erratic boulders in Massachusetts. Although the authors do not specifically mention the Berkshires, they do point out difficulties in Lyell’s theory:

Trains of boulders, such as those already described in Rhode Island, can frequently be traced to some prominent outcrop of the rock in a hill or mountain-peak from which they have been derived. One of the earliest of these to attract attention occurs in the towns of Richmond, Lenox, and Stockbridge, in the western part of Massachusetts. Here a belt of peculiar boulders about four hundred feet [120 m] wide is found to originate in the town of Lebanon, NY, and to run continuously to the southeast for a distance of nine miles [14 km]. West of Pry’s Hill, where the outcrop occurs, no boulders of this variety of rock are to be found, while to the southeast the boulders gradually diminish in size as their distance from the outcrop increases. Near the outcrop boulders of thirty feet [9 m] in diameter occur, while nine miles away two feet [60 cm] is the largest diameter observed.

An Erratic of the Richmond Boulder Trains in the Berkshires

Sir Charles Lyell endeavoured to explain this train of boulders by the action of icebergs during a period of submergence—supposing that, as icebergs floated past or away from this hill in Lebanon, NY, they were the means of the regular distribution described. It is needless to repeat the difficulties arising in connection with such a theory, since now both by observation and experiment we have become more familiar with the movement of glacial ice. What we have already said about the transportation of boulders over Switzerland by the Alpine glaciers, and what is open to observation at the present time upon the large glaciers of Alaska, closely agree with the facts concerning this Richmond train of boulders, and we have no occasion to look further for a cause. (Hayne’s & Wright 70)

In 1852, Lyell delivered a series of public lectures in Boston, in one of which he addressed the question of the Berkshires erratics. At that time, Lyell’s position was still shifting. In November and December 1840, he, Agassiz and Buckland had presented papers on Agassiz’s fledgling Theory of the Ice Age as part of the Geological Society’s winter programme at Somerset House. But the vehement reaction of many of his colleagues took Lyell by surprise and he almost immediately rowed back on his opinion, even to the point of requesting that the Geological Society withdraw his paper of the 4th of December (Boylan 153-156).

This change of heart can be detected in the lectures he delivered during his subsequent tour of North America:

On 20 July 1841, less than three months after his withdrawal of the Geological Society paper and a month after he completed the second edition of the Elements of Geology, Lyell left Britain for the first of his four extended visits to North America. Important new insights into the extent of his retreat from the glacial theory have emerged from Dott’s major study of Lyell in America (1996 and this volume). Particularly informative and relevant is the evidence Dott has uncovered about the syllabus and content of the series of 12 celebrity ‛Lowell Lectures’ that Lyell gave between 19 October and 27 November 1841, which were so popular that, despite using a public theatre with a seating capacity of 2000, Lyell had to present each lecture twice. Dott has reconstructed the programme and outline contents from surviving fragmentary information, including local press reports and Lyell’s rough notes in the Edinburgh University Library. This material leaves little doubt that in Lectures 11 and 12 Lyell had reverted to attributing the ‛Boulder Formation’ to the ‛transporting power of floating glacier ice’ (Dott 1997, pp. 106- 107).

Arctic Sea Ice

This interpretation is explicit in the outlines of later public lecture series in both North America and Britain, for example an 1852 lecture series in Boston, also investigated by Dott (1997, p. 123). Lyell’s notes for these include a diagram showing deep submergence of the Berkshires in Massachusetts and of adjacent areas of New York State. The well known trains of distinctive erratics (Dott 1997, pp. 123-124) were attributed to ‛masses of floating ice carrying fragments of rock’, while there are various reports of Lyell spending many hours on his successive transatlantic crossings on deck looking out for icebergs loaded with boulders and rock debris that would prove his theory (see Dott this volume). (Boylan 157).

In 1855, after Lyell had returned to London, the Royal Institution of Great Britain published an account of a lecture he gave in April entitled On Certain Trains of Erratic Blocks on the Western Border of Massachusetts, United States. The mechanism he describes for transporting the erratics from their place of origin and depositing them in neat parallel lines marks a further evolution in his ideas:

On the western borders of the State of Massachusetts, in Berkshire, and on the eastern confines of the adjoining State of New York, a great number of erratic blocks are seen, remarkable for their large size and their distribution in long parallel trains, each of them continuous in nearly straight lines over hill and dale, for the distance of five, ten, or twenty miles [8-32 km] or more ...

Formation of the Berkshires Erratics (Lyell 1855:92)

Sir Charles then proceeded to explain his theory. He believes that all the large erratics have been transported to the places they now occupy by floating ice,—not by icebergs, nor by terrestrial glaciers, but by coast-ice. The hypothesis of glaciers is out of the question; because, even if we could imagine that in lat. 42° 30 N., the ridges A B C, now only from 1000 to 2000 feet above the sea, once rose, and that at a period, geologically speaking, very modern, to such an elevation as to enable them to generate glaciers, still such glaciers could not have descended from the higher regions in one direction only. They would have radiated from a centre, carrying as many blocks westward as eastward. Their course, moreover, would have been principally S.S.W., or down the valleys now separating the ridges, instead of being south-east, or almost at right angles to the valleys. If, on the other hand, we assume that the country was lower instead of higher, so as to have been submerged beneath the waters of a sea, in which icebergs floated annually from arctic regions, these bergs might bring with them gravel and stones of northern origin, but could not without the aid of coast-ice become freighted with blocks derived from the very region referred to in this discourse, (lat. 42° N.) The northern ice might aid, by chilling the waters of the ocean, and increasing the quantity of coast-ice in a low latitude, but it could do little more.

Suppose the highest peaks of the ridges A B C, in the annexed diagram, to be alone above water, forming islands, and d e to be masses of floating ice which drifted across the Canaan and Richmond valleys, at a time when they were marine channels, separating islands, or rather chains of islands, having a N.N.E. and S.S.W. direction. A fragment of ice, such as d, freighted with a block from A, might run aground, and add to the heap of erratics at the N.W. base of the island B, or passing through a sound between B and the next island of the same group, might float on till it reached the channel between B and C. Year after year two such exposed cliffs in the Canaan range as d and e (Fig. 1), undermined by the waves, might serve as the points of departure of blocks, composing the trains Nos. 5 and 6. (Lyell 92-93)

Big Rock (Middlefield, MA)

Was Velikovsky unaware of this paper when he suggested that Lyell must have felt the weakness of his theory on this point? Velikovsky was incorrect when he claimed that the Diluvial Theory was the only alternative at that time to the Iceberg Theory. Lyell’s 1855 paper shows that he himself had abandoned the Iceberg Theory, albeit for another theory that involved floating masses of ice—ice floes.

Furthermore, Velikovsky’s argument that icebergs cannot act as intelligent carriers can be levelled with equal force at tidal waves and deluges. And while icebergs may not be capable of depositing erratics in long strings, retreating glaciers and ice sheets certainly are. As we have seen, Lyell did consider the possibility that retreating glaciers were responsible for these erratics but rejected it on account of the orientation of the trains of erratics. He also ruled out the possibility that the trains represented terminal moraines:

The drift of Berkshire and of New England in general has a great resemblance to the terminal moraines of glaciers, being unstratified and containing fragments of rock, some angular, others rounded. But the proportion of rounded boulders is far more considerable in the drift than in an ordinary glacier moraine, in which last, as Mr. D. Sharp has lately shown in reference to some Swiss glaciers, the rounded blocks are quite the exception to the rule. Want of stratification is the natural result of the melting of matter out of stationary ice, the light particles and the heavy stones dropping down together, and no current of water sorting the materials, and carrying those of less specific gravity to greater distances. Stones frozen into coast-ice may have been rounded, some by rivers, others by the waves of the sea. (Lyell 95)

Balance Rock Number 1 (Savoy Mountain State Forest, MA)

Today, the erratics in the Berkshires are regarded as glacial erratics, left behind as the Laurentide Ice Sheet retreated. This view gained credence in the 1870s, when Agassiz and his pupil John B Perry reiterated the superiority—as they saw it—of the Glacier Theory (Silliman 68).

Last Words

In 1863, Lyell returned to the question of the Berkshires Erratics for the final time in The Geological Evidences of the Antiquity of Man. His account is essentially the same as the one he gave in 1855, with the same diagrams reproduced. It is also clear that Lyell’s floating masses of coast-ice are not icebergs (as we use the term today), which he only requires to cool the sea, allowing coastal ice floes to form:

I conceive, therefore, that the erratics were conveyed to the places they now occupy by coast-ice, when the country was submerged beneath the waters of a sea cooled by icebergs coming annually from arctic regions. (Lyell 1863:361)

Erratic Boulders and Striated Bedrock (The Prairie, MA)

Icebergs are huge blocks of fresh-water ice that break off from ice sheets and glaciers when these reach the sea. Ice floes, on the other hand, are formed by the freezing of sea water. Nevertheless, ice floes can reach enormous sizes. The ice cap that covers most of the Arctic Ocean is essentially a giant ice floe—albeit one with a covering of snow and fresh-water ice. It is clear from the literature that Velikovsky was not the only person to erroneously ascribe the Iceberg Theory to Lyell. Even Dott’s “floating glacier ice”, which can only mean icebergs, is incorrect. It would be more accurate to ascribe Lyell Drift to ice floes, not icebergs.

Northern or Global?

Lyell’s observation that the erratics seem to be a northern phenomenon must be addressed. If erratics were deposited by mega-tsunamis that swept across the globe due to something as catastrophic as a pole-shift, we would expect them to be ubiquitous over the face of the Earth, not confined to the northern latitudes. Are they?

No, they are not. They are not even confined to the higher latitudes and altitudes, where glaciers and ice sheets can develop. Many erratic boulders can be found in the mid-latitudes, sometimes far from any possible source of glaciers or ice sheets. Geologists have even devised a separate name for such erratics, megaclasts, lest they be confused with glacial erratics. Such megaclasts can be found in places as widely separated as the Mediterranean, the Cape Verde Islands, Mauritius, Hawaii, Kiribati, Tonga, and New Zealand:

Geographical Distribution of Megaclasts (Ruban et al, Figure 4)

Many of these locations are hundreds or even thousands of kilometres from the mainland, and lie in tropical or semi-tropical latitudes. It is inconceivable that such megaclasts could have been deposited in their final resting places by ice. Even mainstream geologists accept this, and megaclasts are now explained as products of tsunamis, mega-tsunamis, and even storms. A recent study showed how several megaclasts in the west of Ireland were shifted by nothing more catastrophic than waves driven by winter storms. One 620-tonne boulder on the Aran Islands moved 3.5 m during storms in 2013-14. A 49-tonne block was found 95 m from its previous location (Cox et al 630). If ordinary storms can shift such objects, there is no limit to the distance a mega-tsunami could transport them.

The South Pacific Island of Tonga is rich in megaclasts—huge blocks of coral limestone, to be accurate. Tonga is about 2000 km from New Zealand and 3000 km from Australia, and it lies in latitude 21° S. The largest of these megaclasts weighs 1600 tonnes and lies 400 m inland (Dewey et al 1984).

Coral Limestone Erratic on Tonga

Politics and Psychology

Velikovsky ends this short section by reiterating his belief that the gradual drift away from Catastrophism and towards Uniformitarianism which occurred in the course of the nineteenth century was a political and psychological trend rather than a scientific one:

But Lyell abhorred catastrophes. He detested them alike in the political life of Europe and in nature. Characteristically, his autobiography begins with this description of the most vivid memory of his early childhood: “I was four and a half when an event happened which was not likely to be forgotten.” His family traveled in two carriages a stage and a half from Edinburgh. “On a narrow road, with a steep brae above, and an equally precipitous one below, and no parapet on the roadside, a flock of sheep jumped down into the road, and frightened the horses [of the other carriage]. Away they ran, and with the chaise, man, horses and all, disappeared clean out of sight, over the brae in an instant.” There was a rescue through the broken pane of glass, a little blood ran, and somebody fainted. [Footnote: Lyell 1:2] It left the first and strongest impression of his childhood in the memory of the author of the theory of uniformity. (Velikovsky 28-29)

A Megaclast on Mauritius

And that’s a good place to stop.

References

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Image Credits

Horace-Bénédict de Saussure: Jean-Pierre Saint-Ours (artist), Collection de la Société des Arts de Genève, Palais de l’Athénée, Geneva, Public Domain
Daniel Tilas: Olof Arenius (artist), Private Collection, Public Domain
Charles Lyell: George J Stodart (engraver), Public Domain
The Richmond Boulder Trains in the Berkshires: © Estate of George William Holmes, _Journal of Glaciology, Volume 6, Number 45, Page 432, Figure 1, International Glaciological Society, Cambridge (1966), Fair Use