Tuesday, November 8, 2016

Charles Lyell and Principles of Geology

Charles Lyell in 1840
I love antique books, and this past year I decided to collect a few notable science books from the nineteenth century. Over these autumn weeks, I plan to write about them on this blog, teaching myself many new things in the process.

I was one of those little kids who loved rocks and geology. I used to know the different types of rocks by sight, and working on poems for my upcoming poetry book, I studied articles from the Illinois State Geological Survey to learn about the geological history of south-central Illinois. It's a fascinating field! And Sir Charles Lyell (1797-1875) and his wife Mary (1808-1873) left us a tremendous legacy.

In my earlier posts about Charles Darwin and Alfred Russel Wallace, Lyell's name came up. As this site puts it, the "Scottish geologist largely responsible for the general acceptance of the view that all features of the Earth’s surface are produced by physical, chemical, and biological processes through long periods of geological time. The concept was called uniformitarianism (initially set forth by James Hutton). Lyell’s achievements laid the foundations for evolutionary biology as well as for an understanding of the Earth’s development."

"Moses and Geology"
by Samuel Kinns (1882) was
a popular book of its time. 
The following mostly derives from that Brittanica.com article. Lyell enjoyed science as a child and at Oxford he grew in his fascination for geology. One of his professors, William Buckland, sought to demonstrate Noah's flood on the basic of cave fossils. Lyell went on to study law and was admitted to the bar, but he continued to pursue his geological interests. During these early years he traveled to North America, France, and back to Scotland on naturalist studies. As this same site indicates, "Lyell was rapidly developing new principles of reasoning in geology and began to plan a book which would stress that there are natural (as opposed to supernatural) explanations for all geologic phenomena, that the ordinary natural processes of today and their products do not differ in kind or magnitude from those of the past, and that the Earth must therefore be very ancient because these everyday processes work so slowly."

Thus "uniformitarianism," contrasted with "catastrophism" that described geological phenomena in terms of catastrophes that altered the planet. Catastrophism was complementary with biblical accounts like the Flood, but the Bible had no information about ancient species and geological data that was becoming known in the eighteenth and nineteenth centuries. As this site puts it, "Lyell emphasized natural law. It makes sense, he said, to assume that geological processes acting in the past were much the same as those we see today — forces such as sedimentation in rivers, erosion by wind, or deposition of ash and lava by volcanic eruptions. This is the principle of uniformitarianism, the reasonable assumption that the forces that acted in the past are of the same sort as those we see acting today."

An 1847 printing, with the
Temple of Serapis on the front cover.
Lyell's book published the first volume of his groundbreaking work, Principles of Geology, in 1830, with exhaustive data to illustrate the new uniformitarian principles that he was developing. Volumes 2 and 3 appeared in 1831 and 1833. Importantly, too, the young Charles Darwin was thrilled with this book, took it with him on his five-year Beagle voyage, and used Lyell's ideas to help him conceptualize his own ideas of the origin and development of species. Darwin also dedicated his journal of his voyage to Lyell, who in turn gave him much advice and help.

Lyell married Mary Horner in 1832, and she also had interests in geology and participated in Lyell's studies, joining conversations with other scientists like Darwin. Lyell became a recognized authority, revising his Principles and also publishing another very popular book, Elements of Geology, that went also went through several revisions and additions. He also wrote two travel accounts of his 1840s visits to North America, and they became classic descriptions of the continent. He was knighted and received other high honors, while continuing his geological work. As the Britannica author writes, "Expanding reputation and responsibilities brought no letup in his geological explorations. With Mary, he travelled in Europe or Britain practically every summer, visiting Madeira in the winter of 1854 to study the origin of the island itself and of its curious fauna and flora. Lyell especially liked to visit young geologists, from whom he felt “old stagers” had much to learn. After exhaustive restudy carried out on muleback in 1858, he proved conclusively that Mt. Etna had been built up by repeated small eruptions rather than by a cataclysmic upheaval as some geologists still insisted. He wrote Mary that 'a good mule is like presenting an old geologist with a young pair of legs.'"
Lyell condensed his large book
"Elements of Geology" into a shorter guide in 1874.

In my previous post about Alfred Russel Wallace, I learned about how Wallace sent Lyell an essay about his work in the Malay islands, which led Lyell to share Wallace's work with Darwin and then to publish Wallace's and Darwin's essays together. The Britannica author: "In 1859 publication of Darwin’s Origin of Species gave new impetus to Lyell’s work. Although Darwin drew heavily on Lyell’s Principles of Geology both for style and content, Lyell had never shared his protégé’s belief in evolution. But reading the Origin of Species triggered studies that culminated in publication of The Geological Evidence of the Antiquity of Man in 1863, in which Lyell tentatively accepted evolution by natural selection. Only during completion of a major revision of the Principles of Geology in 1865 did he fully adopt Darwin's conclusions,
The dark green cover featured a flint ax and
mammoth molar
that had been found at the same level. 
however, adding powerful arguments of his own that won new adherents to Darwin’s theory. Why Lyell was hesitant in accepting Darwinism is best explained by Darwin himself: 'Considering his age, his former views, and position in society, I think his action has been heroic.'”

Mary Horner Lyell (c. 1870)
was a skilled geologist
in her own right and contributed
greatly to Charles' work. 
Sadly, Mary died in 1873, and Lyell survived her only two years. Again, that author summarizes: "Lyell typified his times in beginning as an amateur geologist and becoming a professional by study and experience. Unlike most geologists then and now, however, he never considered observations and collections as ends in themselves but used them to build and test theories. The Principles of Geology opened up new vistas of time and change for the younger group of scientists around Darwin. Only after they were gone did Lyell’s reputation begin to diminish, largely at the hands of critics who had not read the Principles of Geology as carefully as had Darwin and attributed to Darwin things he had learned from Lyell. Lyell is still underestimated by some geologists who fail to see that the methods and principles they use every day actually originated with Lyell and were revolutionary in his era. The lasting value of Lyell’s work and its importance for the modern reader are clear in Darwin’s assessment: 'The great merit of the Principles was that it altered the whole tone of one’s mind, and therefore that, when seeing a thing never seen by Lyell, one yet saw it partially through his eyes.'"

Here is another interesting article: about the way Lyell disseminated knowledge of hominid fossils: https://fossilhistory.wordpress.com/2015/02/19/lyell-the-first-neanderthal/

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