I am trying to assist a very good friend of mine on her masters in history,and from all things she has chosen to analyze the fate of documents, library and instruments of Vilnius University Observatory (1753-1882). I am trying to obtain as much primary sources as available, but with the observatory being the fourth in Europe, the fact that Grand Duchy of Lithuania seized to exist only several decades and all region was in turmoil after turmoil after turmoil (paritions of Polish-Lithuanian Commonwealth, Napoleonic Wars, rebellions of 1833 and 1863 in Poland and Lithuania and subsequent reprisals on academia, WW1, interwar wars of the region, WW2, Soviet occupation to name a few) and the fact that astronomers of the period were really cosmopolitan and spent significant parts of their lives abroad means that I gave to look everywhere for bits of information to make any sense and sometimes just finding a single letter that is mentioned somewhere takes days to find.
I would be really grateful for any links to sites containing primary sources, we are particularly interested in Paris, London, Warsaw, Kiev, St. Peterborough, Berlin, Prague, Lvov libraries and especially in Pulkovo Observatory and Hermitage in Russia, where we know a lot of the artifacts and documents were taken initially. A The astronomers of the period had very close relations with scientists working in those cities and spent significant amounts of time there, so we assume there should be some records and documents relating to that. Also, a lot of instruments were obtained from Ramsden of London, we still have one of his telescopes in Vilnius University. Bode, de Lacaille, Herschel, Ramsden, Stepling had very close working relations with Zebrauskas, Pociobutas, Slavinski, Gusev and others - any correspondence between those gentlemen is of interest too.