Charles Lyell made four visits to North America, and wrote two books about his observations and experiences. His adventures have been recorded and discussed by Wilson (1998).
Wilson, L.G. 1998. Lyell in America: Transatlantic geology, 1841-1853. Johns Hopkins University Press, Baltimore. 429p.
"At Natchez .. there is a fine range of bluffs- several miles long, and more than 200 feet in perpendicular height, the base of which is washed by the river. The lower strata, laid open to view, onsist of gravel and sand, destitute of organic remains, except for some wood and silicified corals, asnd other fossils, which have been derived from older rocks; while the upper sixty feet are composed of yellow loam, presenting, as it wastes away, a vertical face towards the river. From the surface of this clayey precipice are seen, projecting in relief, the whitened and perfect shells of land-snails of the genera Helix, Helicina, Pupa, Cyclostoma, Achatina, and Succinea. These shells, of which we collected twenty species, are all specifically identical with those now inhabiting the valley of the Mississippi." ( 1849, A Second Visit, v.2, p.194)
Lyell, C. 1849. A second visit to the United States of North America. Murray London 2 vols.
Dott, R.H. 1996. Lyell in America- his lectures, field work and mutual influences 1841-1852. Earth Sciences History 15, 101-140.
Skinner, H.C. ed. 1978. Charles Lyell on North American geology; an original anthology. Ayer New York. 226p.
"The resemblance of this loam to that fluviatile silt of the valley of the Rhine, between Cologne and Basle, which is generally called 'loess' or 'lehm' in Alsace, is most perfect. In both countries the genera of shells are the same, and as, in the ancient alluviums of the Rhine, the loam sometimes passes into a lacustrine deposit containing shells of the genera Lymnea, Planorbis and Cyclas, so I found at Washington, about seven miles inland, or eastwards from Natchez, a similar passage of the American loam into a deposit evidently formed in a pond or lake. It consisted of marl containing shells of Lymnea, Planorbis, Paludina, Physa, and Cyclas, specifically agreeing with testacea now inhabiting the United States."
"With the land shells before mentioned are found, at different depths in the loam, the remains of the mastodon; and in the clay, immediately under the loam, and above the sand and gravel, entire skeletons have been met with of the megalonyx, associated with the bones of the horse, bear, stag, ox, and other quadrupeds, for the most part, if not all, of extinct species. This great loamy formation, with terrestrial and fresh-water shells, extends horizontally for about twelve miles inland, or eastward from the river, forming a platform about 200 feet high above the great plain of the Mississippi."
Lyell & Mrs Lyell left Liverpool on 20 July 1841 and returned 27 Aug 1842; that was the first visit. They left Liverpool again on 4 Sept 1845 and returned on 13 June 1846. That was the second visit; the visit of some consequence for loess scholarship; on 13 March 1846 Lyell was at Natchez. The second visit was reported in 'A second visit to the United States of North America' published in 1849. It is said that there was some delay in publication to allow for the publication of scientific results in various journals. In vol.2 are the first(?) descriptions of loess in the USA.
p.208: "Leaving my wife at rest at the hotel, I made a rapid trip by railway, fifty-five miles eastwards, to Jackson, the capital of the State of Mississippi. For the first ten miles, the cars traversed a table-land, corresponding in height with the summit of the bluff at Vicksburg, and preserving an even surface, except where gullies had been hollowed out in the soft shelly loam or loess. These are numerous, and it had been necessary to throw bridges over many of them so as to preserve the level of the road. It was curious to observe, in the cuttings made through the loam, that each precipitous face retained its perpendicularity, as in natural sections, although composed of materials wholly unconsolidated."
p.276. "The distance from Evansville (Indiana) to Louisvill (Kentucky) was 205 miles, and on both sides of the (Ohio) river were hills of liomestone or sandstone, of the coal formation., 300 feet high, frequently presenting steep and picturesque cliffs. Everywhere I observed a flat terrace of loam, or loess, bordering the river, sometimes on the side of Kentucky, sometimes on that of Indiana."
Wilson, L.G. 1998. Lyell in America: Transatlantic geology, 1841-1853. Johns Hopkins University Press, Baltimore. 429p.
Lyell, C. 1849. A second visit to the United States of North America. Murray London 2 vols.
Dott, R.H. 1996. Lyell in America- his lectures, field work and mutual influences 1841-1852. Earth Sciences History 15, 101-140.
Skinner, H.C. ed. 1978. Charles Lyell on North American geology; an original anthology. Ayer New York. 226p.
"The resemblance of this loam to that fluviatile silt of the valley of the Rhine, between Cologne and Basle, which is generally called 'loess' or 'lehm' in Alsace, is most perfect. In both countries the genera of shells are the same, and as, in the ancient alluviums of the Rhine, the loam sometimes passes into a lacustrine deposit containing shells of the genera Lymnea, Planorbis and Cyclas, so I found at Washington, about seven miles inland, or eastwards from Natchez, a similar passage of the American loam into a deposit evidently formed in a pond or lake. It consisted of marl containing shells of Lymnea, Planorbis, Paludina, Physa, and Cyclas, specifically agreeing with testacea now inhabiting the United States."
"With the land shells before mentioned are found, at different depths in the loam, the remains of the mastodon; and in the clay, immediately under the loam, and above the sand and gravel, entire skeletons have been met with of the megalonyx, associated with the bones of the horse, bear, stag, ox, and other quadrupeds, for the most part, if not all, of extinct species. This great loamy formation, with terrestrial and fresh-water shells, extends horizontally for about twelve miles inland, or eastward from the river, forming a platform about 200 feet high above the great plain of the Mississippi."
Lyell & Mrs Lyell left Liverpool on 20 July 1841 and returned 27 Aug 1842; that was the first visit. They left Liverpool again on 4 Sept 1845 and returned on 13 June 1846. That was the second visit; the visit of some consequence for loess scholarship; on 13 March 1846 Lyell was at Natchez. The second visit was reported in 'A second visit to the United States of North America' published in 1849. It is said that there was some delay in publication to allow for the publication of scientific results in various journals. In vol.2 are the first(?) descriptions of loess in the USA.
p.208: "Leaving my wife at rest at the hotel, I made a rapid trip by railway, fifty-five miles eastwards, to Jackson, the capital of the State of Mississippi. For the first ten miles, the cars traversed a table-land, corresponding in height with the summit of the bluff at Vicksburg, and preserving an even surface, except where gullies had been hollowed out in the soft shelly loam or loess. These are numerous, and it had been necessary to throw bridges over many of them so as to preserve the level of the road. It was curious to observe, in the cuttings made through the loam, that each precipitous face retained its perpendicularity, as in natural sections, although composed of materials wholly unconsolidated."
p.276. "The distance from Evansville (Indiana) to Louisvill (Kentucky) was 205 miles, and on both sides of the (Ohio) river were hills of liomestone or sandstone, of the coal formation., 300 feet high, frequently presenting steep and picturesque cliffs. Everywhere I observed a flat terrace of loam, or loess, bordering the river, sometimes on the side of Kentucky, sometimes on that of Indiana."
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