At the start of 1869, Darwin was hard at work making changes and additions for a fifth edition of Origin. He may have resented the interruption to his work on sexual selection and human evolution, but he spent forty-six days on the task. Much of the remainder of the year was spent researching and revising chapters for Descent, and gathering additional material on emotional expression. Yet the scope of Darwin’s interests remained extremely broad, many letters throughout the year touching on subjects such as South American geology, barnacle morphology, insectivorous plants, and earthworms, subjects that had exercised Darwin for decades.
The quantity of Darwin’s correspondence increased dramatically in 1868 due largely to his ever-widening research on human evolution and sexual selection.Darwin’s theory of sexual selection as applied to human descent led him to investigate aspects of the structure and behaviour of other animals more extensively, and to further this programme, he re-established links with specialists who had provided assistance. Considerable correspondence was generated by the long-awaited publication of Variation in animals and plants under domestication. Having been advertised by the publisher John Murray as early as 1865, the two-volume work appeared in January 1868.
Caroline repeats story told to R. W. Darwin of FitzRoy’s feeling of obligation to Captain John White, from whom he gained release to marry Miss O’Brien.
On CK’s "grand and awful" notion of genealogy of man, CD recalls how revolting was the thought that his ancestors must have been like the Fuegians. His present belief that they were hairy beasts is less revolting.
Thanks for Dawson’s letter. Doubts his evidence that climate of land was not glacial when upheaved after submergence.
Encloses memorandum of questions for C. V. Naudin.
Expression of the emotions.
Is building a hothouse for plant experimenting.
JDH’s ideas on America are more atrocious than his. What a new idea that struggle for existence is necessary to try to purge a government! Probably true. Slavery draws him one way one day, another the next. Yankees are "detestable toward us". Tocqueville.
Regrets that his health prevents their meeting, but offers some suggestions for the expedition to the Malay Archipelago and coast of China: the search of caverns in the Malay Archipelago for fossil bones, deep sea dredging in the tropics, glacial action in any moderately steep mountains, means of geographical distribution, the history of domestic animals in these regions, and gestures and expressions of real savages as compared with our civilised expressions. [See5008and5011.]
