Contemplations visual, intellectual and spiritual. In 1891, French painter Paul Gauguin fled to the island of Tahiti - "a sixty-three days' voyage, sixty-three days of feverish expactancy;" begun as an unofficial visit regarding the imminent death of the island's king Pomare -- and resulting in a profoundly moving sea-change (spirit, observation, happiness). The Tahitian theology, natural history, and especially the progress of his relationships - a gift.
This is a good book to read BEFORE embarking on your "desert island" voyage, but beware! Hard to top once you're there on some other island. An exceptional journal, with a graceful translation (it seems) by O. F. Theis from the French. Rated 9 (needs more color plates of paintings! but a lovely, portable paper edition)
Other recommended travel/discovery books:
Off the Map: Bicycling Across Siberia, by Mark Jenkins. 1993 HarperPerennial pb.
Letters from Iceland, by W. H. Auden & Louis MacNeice. 1990 Paragon House pb.
Why Come To Slaka? by Malcolm Bradbury. 1991 Penguin Books pb.
Travels With Lizbeth (writing/homelessness), by Lars Eighner.
The Starship & the Canoe (Freeman Dyson & son George)
Bird of Jove (falconry), by David Bruce. 1994 Texas A&M pb.
The Earthsea Trilogy, by Ursula K. Le Guin
Ishi (anthropology/Native American history), by Theodora Kroeber