A few years ago I stumbled upon The Remarkable Life of William Beebe, by Carol Grant Gould. A fantastic biography about one of the last real explorers (on planet earth).
As a biologist/ornithologist/naturalist Beebe undertook countless expeditions which are hard to summarize in a short blog post. But the most imaginative are his deep sea expeditions with the Bathysphere. From this small steel ball, he descended on a cable to almost 1km deep into the ocean and described the miraculous, luminous life at this depth.
The Bathysphere adventure gets the attention in the recently published The Bathysphere Book by Brad Fox. On the basis of personal notes, drawings and photos, the expedition is further explored in short chapters. With trips to his friendship with Theodore Roosevelt and obsession with Charles Darwin and the Galapagos Islands.