On The Flood, Comets, and a Recantation (1823-1831)

JF Ptak Science Books   Post 2592

I pulled a volume at random of the Annals of Philosophy from the shelves--it was volume VI (new series) from 1823. Trying to think of what might be a hot-button issue (in English) for that year, I started flipping through the pages, reading the page headers: Humboldt on volcanoes, Beaufoy's astronomical observations, Mr. Moyle on the temperature of mines, Prevost on the blood, Pond on some astronomical topic, Ramond on the barometer, book reviews, scientific society announcements, and so on. Nothing really drew me in--until in the back, at page 344, this running header: "Prof. Henslow on the Deluge". That was a "something" that I was looking-but-not-looking-for.  

This was a late-ish contribution to the history of the geology of the Great Flood, and in it, John Henslow (a great naturalist and botanist, 1796-1861) postulates that the flood was caused by the near-passing of a comet that disintegrated and contributed its enormous aequeous "nebulae" to the Earth's atmosphere producing the Noachic flood.  He quickly sites a contemporary (one of many), William Buckland¹, in this, who was one of the late leaders in the geological response to the flood, and who theorized a natural history of the flood and a production of an Ice Age.  The belief that there was some scientific basis in the divinely-induced flood was buoyed by the general flavor of the mythology of the flood, which turns up in more than 100 cultures--so part of the Noahic flood argument as being true is the broad cultural base for it. Commonality across cultures like this doesn't necessarily make something real--there are many many parallels between the Bible and other sacred books besides this, like for example the savior descending into Hell for three days before resurrection, and that in stories that precede the New Testament. So common story bases make them popular, though not necessarily correct.

So Henslow thinks about the comet in a long tradition of Genesis geology, like Buffon and his comet. But what is more interesting to me in this issue is another contemporary, Reverend Adam Sedgwick, Woodwardian Professor of Geology at Cambridge University, who at the end of several decades in theorizing on catastrophic flood geology decided that he had taken a wrong turn.  What happened then, in 1831, was a remarkable refutation of his earlier work. It was an enormous thing, a statement of real courage and conviction to the scientific process.  

"...But theories of diluvial gravel, like all other ardent generalizations of an advancing science, must ever be regarded but as shifting hypotheses to be modified by every new fact, till at length they become accordant with all the phenomena of nature.

In retreating where we have advanced too far, there is neither compromise of dignity nor loss of strength; for in doing this, we partake but of the common fortune of every one who enters on a field of investigation like our own....

Bearing upon this difficult question, there is, I think, one great negative conclusion now incontestably established -- that the vast masses of diluvial gravel, scattered almost over the surface of the earth, do not belong to one violent and transitory period. It was indeed a most unwarranted conclusion, when we assumed the contemporaneity of all the superficial gravel on the earth. We saw the clearest traces of diluvial action, and we had, in our sacred histories, the record of a general deluge. On this double testimony it was, that we gave a unity to a vast succession of phenomena, not one of which we perfectly comprehended, and under the name diluvium, classed them all together.

To seek the light of physical truth by reasoning of this kind, is, in the language of Bacon, to seek the living among the dead, and will ever end in erroneous induction. Our errors were, however, natural, and of the same kind which lead many excellent observers of a former century to refer all the secondary formations of geology to the Noachian deluge. Having been myself a believer, and, to the best of my power, a propagator of what I now regard as a philosophic heresy, and having more than once been quoted for opinions I do not now maintain, I think it right, as one of my last acts before I quit this Chair, thus publicly to read my recantation.

We ought, indeed, to have paused before we first adopted the diluvian theory, and referred all our old superficial gravel to the action of the Mosaic flood...."
(Adam Sedgwick, 1831², p. 312-314)

He was also at the  time the president of the Geological Society of London.  It was a big statement, and would be a big statement at any time.  

I'm happy to have plucked this particular volume from the shelf. 

Notes:

1.  Reliquiae Diluvianae; or, Observations on the Organic Remains Contained in Caves, Fissures, and Diluvial Gravel and on Other Geological Phenomena Attesting the Action of an Universal Deluge, and published earlier that same year.
2.  Sedgwick, Adam. 1831. "Anniversary Address of the President",  Proceedings of the Geological Society of London, 1831, v.1 p. 281 -- 316.

 

 

Comments

[Jim Harrison]

The so-called biblical geology was already a crank position in the early 19th Century, but real geologists like Sedgwick couldn't immediately rule out the theory that there had been a widespread catastrophe in the geologically recent past even if the Biblical account was nothing more than a confused memory of it and could not be taken literally. There was evidence all over Europe and North America of a great event had taken place; but it took a lot of field work to establish that the gravels and erratic boulders were a result of an ice age, not a universal flood.