Charles Darwin wrote On the Origin of Species, the defining document for our understanding of evolution, after a trip to the Galápagos Islands. But the English naturalist didn't dream up his theory in a vacuum after seeing some birds with strange beaks. The voyage to the Pacific islands was lengthy, with much of the 5 year journey spent at sea aboard the HMS Beagle. To keep him company, and to help shape his ideas, Darwin brought an extensive library of books. Now, thanks to funding from the government of Singapore and Charles Darwin University in Australia, those books can be read online.

Darwin's collection comprised of more than 195,000 pages and covered a range of topics. Darwin brought both fiction and non-fiction to occupy his mind on his travels, with history books, geological studies, and atlases joined by literature. Darwin was also a polyglot, and the books he brought were written in varying languages: 125 of the books in the collection are in English, but 38 are in French, nine are in Spanish, seven are in German, one is in Latin, and one is in Greek.

The documents were gathered by researchers at the University of Singapore, transcribed, and uploaded to Darwin website Darwin Online. Users can search through the catalog to find specific entries, or simply skim through the kind of materials that the naturalist had to hand. Particularly fascinating are the illustrations in the collection: both science and fantasy seem to be represented, with geological digrams of mountains and animal skeletons included alongside inaccurate maps and portraits of 18th century tribespeople.