| Reference number | MS/242/34 |
| Level | Item |
| Title | Letter from Friedrich Heinrich Alexander von Humboldt to Thomas Young, dated at Paris |
| Date | 11 July 1816 |
| Description | Autographed letter handed by [Charles] Dupin.
Gives thanks for his election to the Fellowship of the Royal Society and Young's role in it. Particularly proud as he is elected alongside one of his closest friends, [Joseph-Louis] Gay Lussac.
Congratulates Young on his recent discoveries in optics which have been well received in France, noting that Arago has recently made some very complementary experiments.
Recommends [Charles] Dupin to Young, he is a correspondent to the Academie des sciences and has produced excellent treatises on naval construction, he is also well versed in analytical calculations. Enclosed is Humboldt's latest treatise on numerical distribution [of temperature], which verify the average temperatures at different altitudes previously calculated by Cotte, Prevost and Kirvan, combining more exact measurements from around the globe. This creates isothermal lines of average temperatures, which can be deduced from the altitude and the position compared to the equator. This is an extension of the approach taken for magnetic variations. As London and Paris are very close together, the differences should be minimal amd Humboldt encloses monthly average temperatures for London. |
| Language | French |
| Extent | 4p |
| Format | Manuscript |
| Physical description | Paper |
| Access status | Open |
Fellows associated with this archive
| Code | Name | Dates |
| NA7947 | Young; Thomas (1773 - 1829); physician, physicist and Egyptologist | 1773 - 1829 |
| NA7984 | Humboldt; Friedrich Wilhelm Heinrich Alexander von (1769 - 1859); naturalist and traveller | 1769 - 1859 |