One of the greatest nineteenth-century scientist-explorers, Alexander von Humboldt traversed the tropical Spanish Americas between 1799 and 1804. By the time of his death in 1859, he had won international fame for his scientific discoveries, his observations of Native American peoples and his detailed descriptions of the flora and fauna of the 'new continent'. The first to draw and speculate on Aztec art, to observe reverse polarity in magnetism and...