See What Charles Darwin Kept in His ‘Insanely Eclectic’ Personal Library, Revealed for the First Time

On the English naturalist’s 215th birthday, more than 9,000 titles from his expansive collection are now accessible online

A black and white etching of Darwin's study, commissioned a week after Darwin's death. The image shows a full, messy study with many books and papers.
An etching of Darwin's study, commissioned a week after he died. Axel H. Haig / Darwin Online

After nearly two decades of sleuthing and meticulous archival research, academics this week marked the 215th anniversary of Charles Darwin’s birthday on February 12 with a gift for the world: the English naturalist’s complete personal library, published and made publicly available for the first time ever.

A new, 300-page catalog lists some 7,400 titles across more than 13,000 books, journals, pamphlets and reviews Darwin kept in his possession. Close to 9,500 of these works have been copied and made accessible for curious readers to peruse in the digital anthology, “The Complete Work of Charles Darwin Online.”

“This unprecedentedly detailed view of Darwin’s complete library allows one to appreciate more than ever that he was not an isolated figure working alone but an expert of his time, building on the sophisticated science and studies and other knowledge of thousands of people,” John van Wyhe, a historian at the National University of Singapore and leader of the project, says in a statement. “Indeed, the size and range of works in the library makes manifest the extraordinary extent of Darwin’s research into the work of others.”

Most famous for his 1859 treatise On the Origin of Species, which details his theory of evolution, Darwin proposed that humans and animals shared a common ancestor and that species were shaped for survival through natural selection. Alongside his own publications, the new findings show Darwin kept a wide-ranging library of expansive works.

Charles Darwin, photographed in 1868, in profile, looking right; sepia-toned profile; he wears a suit and has grown a bushy white beard.
Charles Darwin, photographed in 1868. Julia Margaret Cameron / Public Domain

In the motley list of titles, books on biology intermingle with books about investments, travel, farming, philosophy, atlases and cures for chronic disease. The naturalist’s collection featured odd sections of books and newspaper clippings entitled “The anatomy of a four-legged chicken,” “Epileptic Guinea Pigs,” “Observations on the blind fish of the mammoth cave” and “The Hateful or Colorado Grasshopper.” In an auction, Darwin won an article by the ornithologist James John Audubon, called “Account of the habits of the Turkey Buzzard (Vultura aura), particularly with the view of exploding the opinion generally entertained of its extraordinary power of smelling.”

The library “shows how insanely eclectic Darwin was,” Van Wyhe tells the Guardian’s Mark Brown. “That’s been the fun part, not the formal books but the other things… all of which pool together to make the theories and publications we all know.”

For years, scholars had assumed the 1,480 books found in two main collections, at Darwin’s home and at the University of Cambridge in England, comprised the majority of his library. But van Wyhe’s work reveals these accounted for only 15 percent of all the scientist’s printed materials.

The thousands of newly uncovered titles were identified in handwritten historical catalogs detailing Darwin’s library, such as one account from 1875, another from 1908 and an entire series of updates, estimated to have been written between the 1870s and 1890s. Darwin also listed reading materials in his notebooks, and Emma Darwin, his wife and cousin, wrote down titles in her many diaries. A variety of other sources—including Darwin’s letters, auction records and owners of private collections—contributed to the list as well.

A painting of the HMS Beagle, the ship Darwin used to sail to South America. Mountains stretch across the background, as a boat with several people sitting floats in the foreground.
A painting of the HMS Beagle, the ship Darwin used to sail to South America. Conrad Martens / Public Domain

Still, some of Darwin’s records were incomplete, missing the name of the author, the date of publication or the title of a complete work that the naturalist had taken a clipping from. Filling in these blanks was a painstaking effort for the team.

“It has been like 5,000 little detective stories—trying to find out which author or article Darwin noted having—it is a joy to strike gold and find the exact source he was referring to,” van Wyhe tells CNN’s Ashley Strickland. “We can now show that originally he had far more in his impressive library.”

Some of his library’s earliest works include an 1818 geography textbook and Oliver Goldsmith’s A history of England, published in 1821, which he won as a prize, the Guardian reports. The majority of the collection is written in English, but nearly half is not—German, French, Italian, Spanish, Dutch and Danish works also appear. And remarkable imagery adorns hundreds of pages, including the first known photograph of bacteria, a sketch of the extinct giant sloth’s skeleton and illustrations of sponges from 1870.

“This shows how determined he was to find out what other men of science had published and to extract information relevant for his theories,” van Wyhe tells CNN.

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