The Challenger expedition was an ambitious scientific mission that sought to catalogue the geology and biology of the world’s oceans. Among other achievements, the expedition managed to scoop up bizarre life forms from the deepest parts of the ocean, including from a spot now known as the Challenger Deep, some 35,000 feet underwater (the expedition brought along over 250 kilometers of Italian hemp rope for just this purpose).
The scientists working aboard the Challenger produced voluminous reports, replete with beautiful illustrations and meticulous charts. Browsing through these documents powerfully evokes the sense of adventure and discovery that made the late 19th century so cool. High quality scans of the entirety of this stunning archive can be viewed here.