The role of Joseph Hamel and Julius Klaproth in the preservation of Johannes Jaehrig's academic heritage (1747-1795)

Johannes Jaehrig is little-known in national and international history. At the same time, he was an employee of the Russian Academy of Sciences for more than 17 years. During his service he collected and systematized numerous data about Mongolian nations. The main reason of Jaehrig scientific “oblivion” was long-distance research expedition and fractional loss of his scientific works. On the basis of academician Joseph Hamel’s letter to the Russian Academy of Sciences it became possible to describe the history of the main part of the linguistic materials of Jaehrig’s personal archive. In 1840 Hamel sent collection of Jaehrig’s works which he bought at the auction of successors of the orientalist Klaproth to St. Petersburg. Analysis of the archive records of the Institute of Oriental Manuscripts of the Russian Academy of Sciences allows to specify present-day location of this collection and identify that Klaproth compile it from Jaehrig’s original draft materials such as Tibet and Mongolian grammar, Mongolian books and manuscripts catalogue, Mongolian logical dictionary. Afterwards Klaproth removed these essential materials from Russia. Academician Joseph Hamel had returned them only half a century later. The archival materials, which help to follow up the fortune of Jaehrig main scientific works are described for the first time. These works contain essential linguistic and ethnographic materials about the Mongols of the 18th century.