Though the name of Robert Mallet was once inevitably associated with the scientific study of earthquakes, it is less well known today. As part of an overdue reappraisal, this essay examines Mallet's major seismological projects and publications, emphasizing his theoretical contributions. Mallet's own claim to be a founder of modern seismology is upheld. Beyond that, however, he is also seen to be an important precursor of plate tectonics.

Benjamin Franklin, the colonial American, maintained a now little-known interest in geological questions for more than sixty years. He began as a follower of English theorists, but soon assimilated some of their ideas with original speculations and discoveries, particularly regarding earthquakes. Though Franklin became famous for his experiments with electricity, he never attempted to explain earthquakes as if they were electrical phenomena; others, however, did. Through his access to American materials, Franklin contributed significantly to the work of several English and (...) French geological theorists. Though some of his own theories were ultimately of limited value, Franklin played an important role in the international science of his time. In addition to his other accomplishments, he was colonial America's foremost student of geology. (shrink)

Though among the most famous earthquakes in modern times, San Francisco has almost always been presented as nothing more than a great human disaster. While certainly that, we should regard it also as having had unusual significance in the development of seismology. Because the full extent of the San Andreas fault was thereafter recognized, and the association between faulting and earthquakes confirmed, we may consider the San Francisco earthquake of 1906 to be the first in which modern understanding of seismic (...) causality prevailed. (shrink)

Speculation concerning the age of the earth begins with civilisation itself. The creation myths of ancient Egypt and other early cultures were soon expanded into elaborate cosmologies by Indian, Persian and Greek philosophers. Jewish and, more insistently, Christian scholars long believed that the Bible provided an exact chronology beginning with the Creation . Such truncated apocalyptic chronologies were opposed first by Aristotelian advocates of an eternal earth and then by deistic freethinkers who regarded the earth's age as indefinite but immense. (...) As textual scholarship cast doubt upon the literal reliability of Genesis, alternative chronologies arose which depended increasingly upon geological evidence. James Hutton's assertions about the earth's age reflect his awareness of this broader context and define his own important contribution to it. (shrink)

Though virtually unknown before 1851, the exceptionally scenic Yosemite Valley of California soon attracted continuing attention as a geological anomaly. J. D. Whitney, state geologist and Harvard professor, advocated a tectonic theory of its origin. Despite its seemingly official status, Whitney's theory even failed to convince some of his own subordinates. An unexpectedly effective dissenter not associated with Whitney was John Muir, then a tatterdemalion vagrant. Though the two men never met, conflict between their inflexible and mutually exclusive geological theories (...) persisted well into the twentieth century. Eventually, both dogmatists were proved wrong, but Muir had come closer to what we now accept. Several geological and geomorphological issues of importance entered into later discussions of Yosemite. The whole controversy, moreover, illuminates such further issues as the influence of preconceptions on theorizing, the role of authority in science, and the interactions of professionals with amateurs. (shrink)

James Hutton knew before its publication that his geological theory would be subjected to religious criticism, and in an eventually rejected preface he endeavoured to mitigate that criticism. His theory is an almost perfect expression of the deistic tenets in which he believed. But he sensed that his attempted defence was inadequate, and so he submitted his preface to William Robertson for advice. Robertson rewrote Hutton's preface for him but also suggested tactfully that it not be published, advice which Hutton (...) took. Upon publication, his theory received its full measure of religious opposition, but it is unlikely that Hutton's preface would have forestalled any of it. I transcribe and attempt to date the preface, discuss its contents, and suggest its usefulness in Huttonian studies. (shrink)

Although the history of the word ‘ geology ’ has often been referred to by those interested in the development of the science, that history has never been fully traced. An endeavor is made to do so here, taking the story at least as far as 1813, by which time the basic word had unquestionably been established in its modern form and meaning. Various claims as to who first gave the science its present name are also briefly examined.

The recent publication of twenty European travel journals originally written in the nineteenth century by William Maclure, the sometime ‘father of American geology’, has entailed major revisions in our understanding of their author. In the present essay I review geological portions of all twenty journals, integrating their contents with Maclure's already known but never before comprehensively discussed publications, which now appear in a new perspective. I then suggest a more adequate evaluation of Maclure's significance within a considerably revised schematization of (...) the history of early American geology. (shrink)

John Playfair left a library of over 1,400 volumes at his death. Analysing these augments our understanding of his mind, particularly with regard to geology. Two questions of special import are why this teacher of mathematics was interested in geology at all, and why, having written his Illustrations of the Huttonian theory of the Earth he never completed the proposed second edition of this famous and influential work.