A missing notebook clutched by a Shropshire lad who circumnavigated the globe, returned to Britain, and demolished the Victorian hubris that humans stood alone as the pinnacle of creation is published for the first time today.

The original notebook, which documents Charles Darwin's observations throughout his five-year voyage to the Amazon, Patagonia and the Pacific aboard HMS Beagle, is presumed stolen, but using a microfilm copy, Cambridge University scientists today make it available free online, along with the entire works of the scientist credited with the most important advance in science of the past 300 years.

The collection brings Darwin's breathtaking range of writing together for the first time, with 50,000 pages of searchable text, and tens of thousands of images, many from previously unpublished manuscripts, together with notebooks, diaries and original publications such as The Origin of Species, The Voyage of the Beagle (the Journal of Researches) and The Descent of Man. Audio versions of key works will be free to download at the project website, darwin-online.org.uk.

"Nowhere possesses this complete collection. It's a complete run of his papers which has never been assembled in any form anywhere," said John van Wyhe, director of The Complete Work of Charles Darwin Online project.

Randal Keynes, Darwin's great, great grandson, told the Guardian the project fulfilled the Darwin family's long-standing aim to have all of the scientist's work available for everyone.