Frederick Burkhardt , James A. Secord, Janet Browne, Samantha Evans, Shelley Innes, Alison M. Pearn, and Paul White, eds. The Correspondence of Charles Darwin . Vol. 19 , 1871 . Cambridge University Press , Cambridge and New York 2012 . 1062 Pages .

In addition to his published works, Charles Darwin left us a trove of notebooks, journals, and book drafts, as well as thousands of letters, which document his thoughts, experiences, sources of information, and personal interactions with unusual completeness. Thanks to the Darwin Correspondence Project, which has been under way since 1975, some 15,000 letters to or from Darwin have been located and are being transcribed, edited, annotated, and published in a chronological series. Under review here is the 19th volume in the series, containing the letters from 1871.

That year is a great time to look in on Darwin. He is 62 years old and a well-established scientific authority. The Origin of Species has been out since 1859 and the early controversies over evolution have quieted down somewhat, but now Darwin is shaking things up again with new arguments about human evolution, adaptation, and sexual selection. The excitement is reflected in the letters, the lion's share of which concern the publication and initial reception of The Descent of Man and work in progress on The Expression of the Emotions in Man and Animals.

In addition to letting us get acquainted with Darwin, his family, friends, and colleagues, the letters also turn out to be an important research tool of Darwin's, with which he gathers information from a large network of authorities. Even The Origin of Species does not rely exclusively on Darwin's own observations or on published literature, but the networking increases in importance for The Descent and The Expression. In a sense, the letters constitute much of the raw data for both of these books.

The networking also allows Darwin to circulate some of his conclusions in advance, test the waters, and smooth the reception of each major publication. These aspects of Darwin's correspondence are on prominent display in this volume in connection with The Descent, which comes out February 24th. Darwin arranges for advance copies to be sent to potential reviewers and likely participants in the ensuing debates. He entertains objections from Alfred Russel Wallace to his reliance on sexual selection to explain animal coloration, enjoys elaborate praise from Ernst Haeckel, puts up with Thomas H. Huxley's feigned annoyance at having to read yet another long Darwin book, and clarifies many details for his Russian, German, French, and Dutch translators. Religious issues come up frequently as Darwin seeks common ground with leading theistic evolutionists such as Asa Gray (who soon counts himself “almost convinced” of his own ape-ancestry) or St. George Mivart (with whom relations deteriorate over the course of the year). He also receives last-ditch appeals from religious authorities to refrain from denying the spiritual dimension of our humanity, and he endures insults from cranks who say he looks like a monkey.

Many of the letters continue or initiate conversations relating to The Descent, concerning human variation, adaptation, and sexual selection or to animal intelligence and morality. Even more respond to Darwin's inquiries for his next book about gestures and facial expressions. Darwin hears, for example, about the finer points of dog behavior and mentality, the tastes of koala bears for tobacco and rum, and the verbal capabilities of a certain African grey parrot, who addresses people by name and even tattles on a family member for taking a glass of ale. Darwin quizzes travelers and anthropologists about expressions and emotions in foreign races and cultures. There is speculation about the physiology and psychology of blushing and whether it is simply too hard to see in the darker skinned races or not possible for them at all. He writes to asylums about expressions of the insane, demented, or paralytic. He wonders about people who have been blind since birth and whether they could exhibit typical facial expressions and gestures without ever having observed them, and he tries to find somebody in the United States who can tell him about Laura Bridgeman, the celebrated deaf and blind woman who was taught to communicate and achieved a high level of education.

To sample just a few of the other scientific discussions, there is one with his cousin Francis Galton about Darwin's 1868 theory of heredity, his “provisional hypothesis of pangenesis,” which Galton is trying to test by transfusing blood among rabbits. Does the blood carry Darwin's hypothetical hereditary particles? There are also some preliminary inquiries and swapping of anecdotes about insectivorous plants and earthworms, the subjects of Darwin's later books. Darwin's Russian translator, the paleontologist Vladimir Kovalevsky, discusses the state of vertebrate taxonomy as well as his brother Alexander's ascidian theory of vertebrate origins. Anton Dohrn tells of his Zoological Station in Naples. There is also continuing discussion of The Origin, the efficacy of natural selection, and the adaptiveness of various organs from duckbills to human nose hairs.

In Darwin's personal life, the big event of the year is the marriage of his eldest daughter, Henrietta, who, as the letters reveal, had more influence on the organization and drafting of The Descent than was once assumed. Most of his other children have left home and there are letters concerning their budding careers.

There is also much to be gleaned from these letters about other aspects of 19th century history. One learns about the publishing industry, for example, as well as early uses of photography, which Darwin investigates for his planned Expression book. Kovalevsky describes crossing the Prussian lines to get to Paris and conditions in that city during the Franco-Prussian war. He also explains how Tsarist censorship works. John Tyndall describes the invention of the first respirator for the use of firemen to filter smoke particles out of the air, which inspires a discussion of the human nose and its filtering functions.

As in every volume of this series, the impeccable editorial work makes the collection easy to use, whether to follow Darwin's life and the progress of his work or to search for discussions of particular biological and anthropological subjects. The letters are dated, arranged chronologically, annotated, and thoroughly indexed. Cross-references are provided among letters on related matters. A biographical register identifies the correspondents, along with any third parties they mention. The online version of these letters is not yet available, but the contents of earlier volumes (currently up to 1868) can be viewed and searched at the Darwin Correspondence Project website,

Associate Editor: M. Wade