The American geomorphology before W. M. Davis, with special regard to J. W. Powell and G. K. Gilbert

Abstract

The beginnings of the North American geomorphology are closely connected with the development of its geology. Many of the most renowned American geologists of the time (up to the end of 19th century) got their real reputation in many cases due to the landforms research. At that time, the countryside and the geological situation in North America was almost completely new for the explorers, especially in the regions that were explored, settled and opened to the public progressively. During the first era, in the middle of 18th century, the American geology and geomorphology depended very much on the European science and this lasted until the second half of 19th century, nearly up to the appearance of W. M. Davis.

The aim of this paper is to give a review of the North American geologists and geomorphologists who lived and worked in this very period and to reveal how both sciences progressed and became more and more successful in explaining the American landscapes, together with giving new universal geomorphological ideas and solutions. Especially the period of Powell and Gilbert was extremely fruitful in this respect and has to be regarded as the dawn of the famous Davisian ideas. This paper, which has been prepared mostly for the readers in Slovenia, is based a great deal on the book The history of the study of landforms, by Chorley, Dunn and Beckinsale (1964). Only the most important names of American geology and geomorphology are mentioned in this summary.

In this Predavisian development it is possible to distinguish the first or the earliest period in the second half of the 18th century, marked by Werner’s theory of the Deluge, and the movement away from it. The most eminent name of that time was Evans Lewis, American cartographer, born in 1700 in Wales, who published a paper on the region between Philadelphia and the Lake Ontario in 1743, and the work on the Appalachian Mountains (1749 and 1752), known at that time as the Endless Mountains. He was one of the first American geologists who developed his own geological view, not being under the influence of Werner’s apocalyptic ideas. Therefore his work was of vital importance for other geologists of the time. Among the earliest geologists and geomorphologists there are also Peter Kalm of Swedish origin, which published Travels in North America (1753), the Frenchman François-Jean Marquis de Castellux (Travels in North America, 1783), B. de Witt (1793) and others.

The prevailing influence of the uniformitarianism of C. Lyell and the opposition to his ideas, represented by the fluvialism of J. D. Dana in the first place, were characteristic of the second period, the first half of 19th century. C. Lyell published the first American edition of Principles of geology in 1837, visited the USA, first in 1841–42, and then in 1845–46, and wrote many other papers on the American geomorphology. He attributed the significant influence on the development of the plains to the sea erosion. In the beginning of 19th century, Benjamin Silliman, an American geologist and professor at the University of Yale (from 1802 onwards), was more successful in exploring geology than others. His scientific newspaper called Silliman’s Journal (1818) was later transformed into American Journal of Science. In 1819 the American Geological Society was established, and in 1836 the Geological Survey.

It was also the period of first strong opposition to Lyell’s ideas, fully developed in the second half of 19th century. L. Agassiz was the second European to whom the American geology and geomorphology owe much clearer ideas of the glaciation. For the first time he lectured in the USA in 1846, but later he even settled in the country forever. He strongly influenced A. Conrad (1839) and especially E. Hitchcock (1841) who finally opened a new chapter in American glacial geomorphology.

The second half of the 19th century is the third period of the early development of the American geology and geomorphology, referring, on one hand, to the time of their slow and progressive decline from the European ideas and perceptions in explaining the landforms, but on the other hand, to explorations of the American West. Between 1846 and 1875 there was a strong argument between the defenders of Lyell’s ideas, in favor of the prevailing influence of marine erosion, and the opposition, being in favor of fluvial erosion. In 1843 generalist James Hall published a description of glacial landscape and material.

Another scientist, James Dwight Dana, was the most important fluvialist, well known for his descriptions of fluvial processes in Hawaii and Australia. He totally refused the idea of marine terraces. His Manual of geology (1863) is often compared with Lyell’s Principles, and Dana is therefore regarded as the first great American geologist. A group of the so-called structuralists and semi-catastrophists, represented by W. Hopkins and others, were against Lyell as well. They believed that the present surface is remaining of the past and thus an effect of fluvial erosion, the belief, which had its origin with J. Hutton. A. Ramsay belonged to the same group as well, although he defended the marine planation, but in a different way than Lyell. Therefore his idea was comparative with later Davisian planation. E. Hitchcock (1849) was partly in favor of Lyell’s marine terraces, in the case of Connecticut, but he also believed in lacustrine, fluvial and glacial origin of terraces. About 1866 the fluvial idea was more or less accepted in general, and also C. Lyell himself partly changed his statements in this respect at the end of his life. But in discussions, in favor of fluvial erosion J. D. Dana, G. Greenwood, A. Ramsay and J. B. Jukes contributed the most. Also J. P. Lesley from Philadelphia has to be mentioned in this respect because of his arguments for the importance of rock resistance in erosional processes. He was among the first who tried to explain the origin of the Appalachian structural landscape. His work signified the beginning of more appropriate regard for the importance of geological structure in the surface development.

In the middle of 19th century first attempts were made in quantification of geomorphic processes and effects, as well as in landforms morphometry. C. Lyell, e. g., tried to establish the speed of the Mississippi delta development, which, according to him, could be about 67,000 years old (1847). American geologists A. Brown and M. W. Dickeson calculated a much shorter period of its development, only about 14,000 years.

The time before W. M. Davis and his theory of geographical cycle was a very important period of geological and geomorphological explorations in the American West. The leading American explorers and thinkers of that time were F. V. Hayden, J. S. Newberry, G. N. Wheeler, and most of all J. W. Powell, G. K. Gilbert and C. E. Dutton.

The government of the USA in 1834 organized the very first geological expedition to the West, although the first scientific expedition under the leadership of doctor and naturalist J. S. Newberry was organized in 1855. Later, in 1859, an expedition to Santa Fe and southern Utah was organized as well. F. V. Hayden explored the Dakota badlands, the Plate River, the Black Hills and the upper Missouri together with Yellowstone.

At that time G. P. Marsh, a teacher, philosopher, ambassador and scientist, published Man and nature, or physical geography as modified by man action (1864), and influenced philosophy with its anthropocentric geomorphology.

After the Civil War beside Powell, F. V. Hayden, C. King and G. N. Wheeler explored the geology of the American West.

John Wesley Powell (1834–1902) is perhaps the first name of the American and world geomorphology of 19th century. He is well known for exploration of the Great Colorado Canyon (1869), emphasizing river erosion, for the theory of absolute and temporal erosional base, classification and terminology of landforms, drainage basins, genetic types of rivers and structural types of valleys. He is also the author of the concept of recent uplift of the surface. In 1879 he helped in foundation of Geological Survey and Land Office.

Grove Karl Gilbert (1843–1918) was the second most important geologist and the »geomorphologist’s geomorphologist« (Tinkler, 1985) of the late 19th century. His most famous work is perhaps the Report on the geology of the Henry Mountains (1877), which was the first important geological study on mechanics of river processes. But he also has merits for many new ideas, e. g. the theory on dynamic equilibrium of river profile and concept of grade, which were crucial in constructing of Davisian geographical cycle (Tinkler, 1985). His geomorphological »inventions« were also the explanation of upwarping of the shorelines of ancient Lake Bonneville, by the help of isostatic recovery of the crust after the end of the ice loading (1871–72), further on the study of climatic influence on land forming, the law of uniformity of the slopes, the laws of declivities and structure, the law of divides, the idea of lateral planation and origin of pediments.

Another important geomorphological thinker before W. M. Davis was Clarence Edward Dutton (1841–1912). At first, he was under the influence of J. W. Powell, whom he met in 1871. Later (1879) he was in charge of geological investigations in the region of the Colorado River. His first published works were on isostasy (1871–72 and 1889), the theory of contraction of Earth’s core (1874) and the general physical development of Earth (1876). Later he published his most famous work Report on the geology of the high plateaus of Utah (1880), in which he stated that the area is a »paradise for geologists«. He is the author of the Physical geology of the Grand Canyon district (1880–81) and Tertiary history of the Grand Canyon region (1882). All his works are written in excellent and colorful language. Among others his merit was the advance of the isostatic theory, which in Europe was taken into account only thirty years later.