Comments extensively on CL’s book [Travels in North America (1845)]. Lyell’s views on slavery, the clergy, education, and coalfields. Has difficulty in tracing Lyell’s course. Comments on geological portions, especially CL’s comparisons of living and fossil organisms to those of South America and Tasmania; animal formation of carbonic acid and effects of vegetable decay; Indians’ use of lumber. Discusses water-borne transportation of wood, fruit, and seeds. Notes distribution of Arctic flora.

Discusses the power of land covered with snow to radiate heat.

Criticises CL’s discussion of slavery [in Travels in North America (1845)]. A review of CL’s book is in Gardeners’ Chronicle.

Mentions John Lindley’s views on carbonic acid gas and extinction;

refers to the discussion of multiple and single creations in Humboldt’s Kosmos.

The origin of volcanic craters of elevation.

There is a popular demand for a new edition of Principles.

Praises palaeobotanical work of C. J. F. Bunbury.

Discusses American Negroes and their parasitic lice. Henry Denny’s need for lice specimens.

Discusses effects of racial crosses in man.

Describes his trip to Yorkshire.

Comments on Sedgwick’s review [of Vestiges of creation].

Mentions Humboldt’s Kosmos. Criticises Humboldt’s geology.

Comments on forthcoming edition [7th (1847)] of CL’s Principles. Mentions other books relevant to CL’s needs by Hooker, H. G. Bronn, Edward Forbes, and J. G. Kölreuter. Discusses his own books on volcanoes and the geology of S. America.

Mentions expected visit to Down by the Lyells.

Discusses A. C. Ramsay’s article ["On the denudation of South Wales", Mem. Geol. Surv. G. B. 1 (1846)]. Mentions his own paper ["Volcanic phenomena in South America", Collected papers 1: 53–86]. Emphasises that sedimentary deposits are not ordinarily preserved.

Replies to note from CL asking about views of glaciers.

Quotes from South America [p. 167] on the foliation of metamorphic rocks.

Asks CL to address a letter to Charles Maclaren.

Discusses recent publication by David Milne on erratic boulders [Edinburgh New Philos. J. 42 (1847): 154–172].

Views of Bernhard Studer on foliation of gneiss in the Alps. Asks CL to tell Leonard Horner of Studer’s views.

Comments on investigation of coral reefs by A. A. Gould, particularly the reefs around Tahiti. Mentions description of reefs of Tahiti by W. Forbes.

Hooker’s view of work by C. J. F. Bunbury.

Has received copy of CL’s Principles [7th ed.].

Comments on reading Annales des sciences naturelles.

David Milne’s and Robert Chambers’ views on Glen Roy.

Mentions sales of South America.

Describes visit to his father at Shrewsbury.

Comments on correspondence between CL and Whewell [concerning university reform].

Criticises S. G. Morton’s "Hybridity in animals" [Am. J. Sci. 2d ser. 3 (1847): 39–50, 203–12].

Discusses David Milne’s Glen Roy paper ["On the parallel roads of Lochaber", Trans. R. Soc. Edinburgh 16 (1849): 395–418]. Rejects Milne’s theory that outlet of Glen Roy is blocked by detritus. Impressed by Milne’s discovery of an outlet at the level of the second shelf. Believes this strengthens theory that lakes were formed by glacier blocking Glen Roy. Offers arguments against glacier theory.

Discusses enclosed figures on elevation of terraces in several Scottish glens as surveyed by William Kemp and David Stevenson. Comments on Robert Chambers’ view of the terraces. Mentions a letter on the terraces, originally written for publication, which he has asked Robert Jameson [editor of the Edinburgh New Philos. J.] to destroy.

Comments on Ann Susan Horner’s escape in a dangerous incident at sea.

Compares addresses by William Buckland and CL, delivered at recent meeting of the Geological Society.

Discusses the views on Glen Roy in Chambers’ Ancient sea-margins [1848].

Speculates that Chambers wrote Vestiges [of creation (1844)].

Comments on apology by Chambers for using some of CD’s material without acknowledgment in discussing Glen Roy. His opinion of Chambers’ book [Ancient sea-margins (1848)].

Congratulations on CL’s knighthood.

Mentions illness of Emma Darwin.

Comments on CL’s Second visit to the United States [1849].

His water treatment by J. M. Gully.

CD’s contribution ["Geology"] to J. W. Herschel’s Manual of scientific enquiry [(1849), Collected papers 1: 227–50].

Discusses CL’s Second visit to the United States [1849]. Corrects CL’s error regarding location of Megatherium finds.

Discusses effect of subsidence and elevation on deposits. Cites examples along coasts of South America and Wales. Proposes theory to explain thickness of deposits in south Wales.

Asks CL’s opinion of his theory of "craters of elevation" described in Volcanic islands.

Mentions CL’s comparison of Mississippi beds to the Pampas.

Comments on Poulett Scrope’s views on the separation of basalt and trachyte.

Describes his cirripede work.

Discusses CL’s refutation of CD’s concept of "craters of elevation" and CL’s new concept of "craters of denudation". Mentions examples of such craters. Admits that his own concept of these craters was unsatisfactory. Urges CL to publish article ["On craters of denudation", Q. J. Geol. Soc. Lond. 6 (1850): 207–34].