Genesis and Genes is now available in Israel, the UK and the USA. It is expected in South Africa in January 2013. In the meantime, I intend to post a number of sample passages. Here is an excerpt from chapter 3.
[Lord] Kelvin was eclectic in his scientific interests. His mastery of physics was destined to make a deep impact on a number of disciplines, particularly geology. He had a special interest in physical geology, and his insights would shake this field. The theory he would upset was embodied by the most distinguished geologist of that era, Charles Lyell (1797- 1875). Lyell, a close friend and mentor to Charles Darwin, trained in law, but his interest lay in science, particularly geology. In 1825, he was asked to write for the Quarterly Review, and began to contribute essays and book reviews on scientific topics. He was a talented writer, and the Quarterly Review brought him to the attention of a wide circle of educated people. In 1827 he decided to write a book on geology, and he subsequently set out to gather material for the book. His expedition of 1828 would be his most important. In May of that year, Lyell travelled to Paris, where he had arranged to meet the geologist Roderick Murchison (1792-1871), and together they travelled south, then along the Mediterranean coast to northern Italy. At the end of September, Lyell pressed on towards Sicily, the nearest location to mainland Europe of volcanic and earthquake activity. It was what Lyell saw in Sicily that convinced him that the Earth had been formed by the same processes that are at work today, operating over immense spans of time.
By February 1829 Lyell was back in London, and got to work on his book. He drew extensively on the work of geologists from throughout the continent, producing by far the most thorough overview of geology that had ever been written. The first volume of Principles of Geology (a name deliberately chosen to echo Newton’s Principia) appeared in July 1830. It was subtitled Being an attempt to explain the former changes of the Earth’s surface, by reference to causes now in operation. The book was an immediate success. After another stint of fieldwork, this time in Spain, the second volume of Principles appeared in January 1832. In 1833 Lyell resigned from the chair of geology at King’s College in London, a position he had accepted in 1831, to devote himself to writing. He thus became probably the first person to make a living as a science writer. The third volume of Principles appeared in April 1833, and for the rest of his life, Lyell devoted himself to updating his book, the twelfth and final edition appearing posthumously in 1875. Lyell was knighted in 1848 and made a baronet in 1864, and was widely acknowledged to be the leading geologist of the era. [Science: A History, John Gribbin, Penguin Books, 2003, pages 319-329.]
I wrote above that Lyell’s Sicilian experience shaped his view of geology. He became convinced that geological processes that are observed today are sufficient to account for all geological features of Earth, if they could be assumed to have operated over enormous spans of time. His approach to geology became known as uniformitarianism, a (dreadful) word coined by William Whewell (1794-1866). The doctrine had been suggested by James Hutton (1726-1797), considered the father of modern geology, but Lyell popularised it and placed it on a firm empirical foundation. Uniformitarianism was distinguished from catastrophism, which viewed the Earth’s geology as being shaped mostly by cataclysmic events such as the Biblical Flood. In contrast, uniformitarian geologists insisted that geology was explainable on the basis of the same processes that operate today. They saw no need to invoke catastrophes such as global floods. The slow, gradual geological processes that are observable today – erosion, for example – are sufficient to explain all features of Earth’s geology. By the 1850s, uniformitarianism was the dominant geological doctrine in Britain, which was then (and for decades to come) the leading international centre of geology.
If the vast reserves of force demanded by the catastrophists were to be rejected, they had to be replaced; Lyell’s substitute was time. He saw time as indefinite or inconceivably large, although he avoided speaking of infinite time. Lyell’s view of the Earth was that it was overall stable through vast ages, being in a state of dynamic balance. Thus, his conception of a steady-state Earth provided no real reference point from which to measure time. But the idea of various cycles in which Earth’s energy was maintained indefinitely amounted to a perpetual motion machine. This is where Lord Kelvin’s expertise made its strongest impact.