Abstract The Town Creek locale in Jackson, Mississippi exposes fossiliferous strata through stream erosion and provides evidence for stratal doming atop an extinct volcano. Charles Lyell (1797–1875) investigated the locale on his second visit to North America (1845–46) and concluded that Town Creek fossils were older than Vicksburg fossils, and that strata dipped westward from Jackson. In the 1850s, Mississippi's state geologist Eugene Hilgard (1833–1916) recognized the first volcanic doming evidence and correctly concluded that a ‘local upheaval’ had elevated the Jackson area. Subsequent research revealed an extinct volcano as Jackson Dome's source, explaining the strata dip and Lyell's observation that Jackson's Eocene fossils were older than Vicksburg fossils, later identified as Oligocene. The Jackson fossiliferous strata, known today as the Moodys Branch Formation, exquisitely preserves fossils that have contributed to numerous scientific investigations. The Town Creek locale was threatened in 2003 when a proposed flood control project would have inundated it. Scientists rallied for the preservation of the geologically and historically important Town Creek, and today it remains as a geoheritage site available to scientists and the public, with a state historical marker noting its geological importance. Long-term preservation of the locale is needed but not guaranteed.

Abstract Charles Darwin's research during the second voyage of HMS Beagle is examined within the context of Charles Lyell's ideas on crustal movement. Darwin's pre-voyage training is summarized and the impact on his own subsequent theorizing of his commitment early in the voyage to a Lyellian theoretical framework is analysed. Two sites studied by Darwin which he interpreted as strong support for Lyell's theory of vertical crustal mobility are examined: the first is Signal Post Hill in the Cape Verdes, visited in 1832; the second is Agua de la Zorra in Argentina, visited in 1835. Darwin's work at both sites was key to his first theory of globally-balanced elevation and subsidence as an explanation for the structure and distribution of coral reefs. The case is made that both sites are of international geoheritage importance and that their protection should be assured with enhanced access and interpretation.

Abstract The Pliocene fossiliferous succession of the Volterra hill, a prominent place in Tuscany, Italy and, since the Renaissance, the site of important archaeological finds of the ancient Etruscan civilization, has formed the object of enquiry over six centuries of research on the inner nature of the Earth system. The works of Restoro d'Arezzo, Leonardo da Vinci, Nicolaus Steno, Giovanni Targioni, Nicolas Desmarest, Giambattista Brocchi, Alexandre Brongniart and Charles Lyell testify to the early recognition through fieldwork that those strata with seashells had formed at the bottom of the sea. This interpretation served different approaches to knowledge. Restoro, Leonardo and Steno, spanning nearly four centuries in the history of science (1282–1669), including the ‘Copernican Revolution’ and the start of the Modern Age, relied also on textual sources and trusted a speculative model of the Earth's interior, so that at Volterra they focused on vertical movements of the earth–water system. The authors of the eighteenth and nineteenth centuries abandoned pre-built young-Earth models and emphasized the geography of ancient Tuscany. Brocchi, Brongniart and Lyell promoted the taxonomic use of seashells to correlate rocks across Europe. This place deserves higher standards of valorization to promote understanding of the history and sociology of ideas.

James Hutton’s Theory of the Earth , first published in 1785, was considered completely new by his contemporaries, different from anything that preceded it, and widely discussed both in Hutton’s own country and abroad—from St. Petersburg through Europe to New York. Yet a recent trend among some historians of geology is to characterize Hutton’s work as already behind the times in the late eighteenth century and remembered only because some later geologists found it convenient to represent it as a precursor of the prevailing opinions of the day. Painstakingly researched, richly referenced, and full of interesting stories, this Memoir shatters that line of thinking and restores Hutton’s standing as the father of modern geology, his ideas fully relevant to the geological problems of his day.

Abstract In the early 1830s Charles Lyell was convinced that much of western Europe had been submerged during the Pleistocene by cold seas strewn with icebergs; the relicts of whose loads of rock and mud occurred on land as boulder clay and erratic blocks. Swiss scientist Louis Agassiz disagreed, considering in 1837 that these were the products of deposition by a great ice sheet. Archibald Geikie realized by 1863 that Lyell was wrong. Mountain glaciers had carved the topography of Scotland and other parts of the UK, feeding an ice sheet that left glacial erratics behind when it melted away. He hoped, in vain, to change Lyell’s mind. Archibald Geikie’s mantle passed to his brother James, who compiled evidence from around the world to demonstrate the correctness of his brother’s thesis. It was published in 1874 just before Lyell died still arguing for the correctness of his iceberg theory, which gave us the word ‘drift’ for the unconsolidated deposits mantling the UK. Even so, by then Lyell had gone some way – no doubt partly influenced by the Geikies – to accepting that in certain instances glacial action had, indeed, moved large erratic blocks – locally even uphill, as in the Jura.

ABSTRACT The historic town of New Harmony is located along the Wabash River in Posey County, Indiana, and served as a focal point for natural scientists, especially geologists, in the early nineteenth century. Notable geologists that lived and worked in New Harmony during this time include Edward Travers Cox, William Maclure, Fielding Bradford Meek, Joseph Granville Norwood, David Dale Owen, Richard Dale Owen, Benjamin Franklin Shumard, Gerard Troost, and Amos Henry Worthen. Other natural scientists who worked in New Harmony include Charles Alexandre Lesueur and Thomas Say, and the town was also visited by James Hall, Leo Lesquereux, Sir Charles Lyell, and Alexander Philipp Maximilian, Prince of Wied. The purpose of this field-trip guide is to highlight the scientific and geologic enterprise that operated in nineteenth-century New Harmony, Indiana. There will be a tour of historic buildings including laboratories used by David Dale Owen, such as the Rapp-Owen Granary and his fourth laboratory, which was constructed in 1859. Furthermore, field-trip participants will visit a new geology exhibit at the Working Men’s Institute, an organization established by William Maclure in 1838. The field excursion will also visit historically significant localities, including Mississippian and Pennsylvanian exposures, the type section of the West Franklin Limestone, and a Pennsylvanian paleobotanical site that yielded extensive collections of plant fossils in the mid-nineteenth century. Finally, this field trip will provide an opportunity to discuss the importance of art to geological studies in the early nineteenth century. Specifically, hand-colored geologic maps, cross sections, and renderings of fossils were included with many of the scientific reports of historic New Harmony, and are reflected by the superb artwork of Charles Alexandre Lesueur, David Dale Owen, and Thomas Say. Access to view their original scientific artwork is possible only through special arrangement with the Working Men’s Institute.

The geological record represents the only source of data available for documenting long-term historical patterns of extinction intensity and extinction susceptibility. Such data are critical for testing hypotheses of extinction causality in the modern world as well as in deep time. The study of extinction is relatively new. Prior to 1800, extinctions were not accepted as a feature of the natural environment. Even after extinctions were recognized to have occurred in Earth's geological past, they were deemed to have played a minor role in mediating evolutionary processes until the 1950s. Global extinction events are now recognized as having been a recurring feature of the history of life and to have played an important role in promoting biotic diversification. Interpretation of the geological extinction record is rendered complex as a result of several biasing factors that have to do with the spatial and temporal resolutions at which the data used to study extinctions have been recorded: fluctuations in sediment accumulation rates, the presence of hiatuses in the stratigraphic sections/cores from which fossils are collected, and variation in the volumes of sediments that can be searched for fossils of different ages. The action of these factors conspires to render the temporal and geographic records of fossil occurrences incomplete in many local stratigraphic sections and cores. In some cases, these stratigraphic and sampling uncertainties can be quantified and taken into account in interpretations of that record. However, their effects can never be eliminated entirely. Testing hypotheses of global extinction causality requires acknowledgment of the uncertainties inherent in extinction data, the search for unique predictions of historical patterns of variation or associations that can, in principle, be preserved in the fossil record and tied logically to the operation of specific causal processes, and to adoption of an explicitly comparative approach that establishes the presence of multiple instances of the predicted cause-effect couplets within a well-documented chronostratigraphic context.

Theory choice, the problem of accepting/rejecting scientific theories, is philosophically interesting in part because it involves appeal to nonempirical factors that can only be justified by philosophical considerations. The emphasis in this paper is on the historical as opposed to the experimental sciences—including astronomy, evolutionary biology, and especially historical geology—with examples taken from seventeenth through nineteenth centuries. The fact that evidential reasoning inherently requires a choice of philosophical/methodological principles is demonstrated through reference both to historical cases and to general philosophical considerations. This paper argues that methodological principles play a crucial role in turning empirical data into evidence for/against theories, and it outlines some of the particular evidential and methodological difficulties faced in the historical sciences. Choices of methodological principles depend on nonempirical factors, and because definitive arguments can rarely be found, they are largely a matter of judgment. “Scientific” debates are thus sometimes really disputes over philosophical taste and judgment. Moreover, it is often the case that clear judgments about the incorrectness/correctness of a methodological principle used in a specific context can only be made retrospectively. In part by looking at connections among Isaac Newton, David Hume, and Charles Lyell, and in part by examining Lyell’s own arguments, I argue that it was reasonable for Lyell to adopt uniformitarianism as a central methodological principle. Through arguments and historical examples, I also show that there are limits to the acceptability of the uniformitarian position.