Summary

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

Summary

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].

Summary

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].

Summary

Continues discussion of Dana’s Geology [1849]. Comments on dikes of Hawaiian volcanoes and Dana’s view of craters of denudation. Compares role of sea and rivers in forming valleys. Criticises Dana’s treatment of CD’s account of coral reefs.

Summary

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.

Summary

Criticises Élie de Beaumont’s view of a right angle junction of a stream of lava and a dike.

Mentions his misgivings in voting to recommend J. D. Forbes for Royal Medal.

Notes Daniel Sharpe’s work on mica schist.

Summary

Discusses J. D. Dana’s Geology [1849]. Pleased that the part on corals confirms his views [Coral reefs (1842)]. Discusses Dana’s observation that in Sandwich Islands lava streams often join dikes at right angles with no cone. Retracts earlier denial of this possibility. Criticises Dana’s view of Australian valleys.

Summary

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.

Summary

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)].

Summary

Discusses CL’s paper, "On craters of denudation" [Q. J. Geol. Soc. Lond. 6 (1850): 207–34], which "will be a thorn in the side of É[lie] de B[eaumont]". Notes evidence from Galapagos overlooked by CL. Mentions other examples of craters.

Summary

Discusses Louis Agassiz’s theory of the glaciation of Brazil.

Summary

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.

Summary

Discuss CL’s suggestions for revisions to the chapter on the geological record [Origin, ch. 9].

Henry Holland’s reaction to the book.

Comments on CL’s work on flint tools of early men.

Describes at length a conversation with Owen concerning Origin. Notes "that at bottom he goes immense way with us", but emphasises Owen’s unfriendly manner. Remarks that Owen accepted a relationship between bears and whales. "By Jove I believe he thinks a sort of Bear was the grandpapa of Whales!"

Has heard Herschel considered his book "the law of higgledy-piggledy".

Summary

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.

Summary

Speculates about cause of inclination in unusual columns of lava. Suggests CL check with William Hopkins about sliding movements in viscid matter.

Comments on CL’s expedition to Madeira.

Summary

Returns Lake Superior [1850], which he already has received from Agassiz. Thanks for pamphlets by C. B. Adams [on Mollusca, Contrib. Conchol. 10 (1851): 189–206; 11 (1852): 207–15].

Describes his dissection of an unusual cirripede [Alcippe lampas] with 12 males attached [see Living Cirripedia 2: 556, 558].

Summary

Explains how melting of ice in Glen Spean could have successively freed two lower cols, thus establishing the water-levels that determined the two lower shelves in Glen Roy.

Plans to read a paper to the Linnean Society ["Sexual forms of Catasetum", Collected papers 2: 63–70].

Summary

Comments especially on the "intermediate shelf" problem of Glen Roy; views of Jamieson and Milne. CD "cannot help a sneaking hope that the sea might have formed the horizontal shelves".

Summary

Discusses views of Daniel Sharpe on foliation and cleavage. Recalls his own previous discussion [in South America].

Summary

Discusses a proposed expedition to Australia. Urges collecting and investigating productions of isolated islands. Recommends dredging the sea-bottom.

Mentions keeping Helix pomatia alive in sea-water.