Jon Turk has kayaked around Cape Horn, traversed the Northwest Passage and paddled across the Pacific Rim. But, the strangest trip he ever took was the journey he made as a man of science into the realm of the spiritual. In 2000, in the remote Siberian village of Vyvenka, Jon Turk met an elderly woman named Moolynaut, a Koryak shaman, and learned about her voyages to the spirit world. A year later, Moolynaut entreated the spirit of a great, black...