A collection of letters and notes on Muir's eight-month voyage in 1911-1912, which took him up the Amazon, along the Pacific coast of South America and up into the Andes. He returned via Southern and Eastern Adrica, with excursions to the Zambezi, Lake Victoria, and the Headwaters of the Nile. Edited and annotated by Robert Michael Pyle.  (SAM78, $29.95)