HUMBOLDT, Alexander (1769-1859, Prussian geographer, naturalist and explorer)
An autograph letter signed ('Le Bn de Humboldt') to an unidentified 'Monsieur le Duc'; it is a letter of introduction for the geologist [Alexandre] Brongniart. Paris, 27 March 1820; small quarto, 2 pages, with a conjugate blank leaf; thin strip of tissue-paper on the outside rear page, and minimal loss to this blank leaf near the centre of the hinge (both as a result of having been mounted in, then removed from, an album); light creases where folded in four for posting; in excellent condition
Humboldt remembers with gratitude the assistance rendered by le Duc to himself and his friends and collaborators, [Louis Joseph] Gay-Lussac and [Christian Leopold von] Buch. He hopes that M. Brongniart, 'l'homme célèbre', who wishes to visit Vesuvius and the lava flows of Ischia [a volcanic island near Naples], will be afforded similar kindnesses. Alexandre Brongniart (1770-1847) was a French chemist, mineralogist, and zoologist, who collaborated with Georges Cuvier on a study of the geology of the region around Paris. In 1800 he was appointed director of the porcelain manufactory at Sèvres, a position he held until his death 47 years later. Alexander von Humboldt (in full, Friedrich Wilhelm Heinrich Alexander, Freiherr [Baron] von Humboldt) was a major figure in the classical period of physical geography and biogeography. His book 'Kosmos' (1845) made a valuable contribution to the popularization of science. Numerous species and geographical features have been named after him, not least the Humboldt Current off the west coast of South America (biographical details courtesy of Encyclopaedia Britannica and Wikipedia, both online).