Charles Darwin's entire personal scientific library - including his own scribbled notes in the margins - is to appear online for the first time.
The 1,480 books, most of which are held at Cambridge University Library, have been digitised in conjunction with several other libraries and museums.
Although most are scientific, some are humanities texts on subjects that Darwin found interesting from a scientific point of view.
The team says 730 contain abundant research notes in their margins. For example, Darwin's friend Charles Lyell wrote in his Principles of Geology that there were definite limits to the variation of species. Darwin wrote alongside this: "If this were true adios theory".
The first 330 of the most heavily-annotated books are already available.
"The Darwin collections are among the most important and popular held within Cambridge University Library. While there has been much focus on his manuscripts and correspondence, his library hasn’t always received the attention it deserves – for it is as he engaged with the ideas and theories of others that his own thinking evolved," says University librarian Anne Jarvis.
"Because Darwin’s evolutionary theory covered so many aspects of nature, reading served him as a primary source of evidence and ideas. Darwin once complained that he had become a 'machine for grinding general laws out of large collections of facts'."
Along with the raw images of the books and transcribed jottings, the information is indexed and searchable. It's here.