1732-1808 1770-1846 1774-1852 1784-1846 1785-1842 1803-1844 18thcentury 19thcentury alexandervon attitudes biography callcott correspondence correspondencebessel correspondencehumboldt criticismandinterpretationhumboldt criticismandinterpretationkruzenshtern criticismandinterpretationlangsdorff cross-culturalstudies descriptionandtravel european expeditions flora foreign german germans germany history historyandcriticism humboldt ivanfedorovich josécelestino latinamerica maria mexico mutis naturalists pt science scientificexpeditions scientists socialaspects sociallifeandcustoms sources travel travelers'writings travelhumboldt tristan visitors wz100h881h2004