List Konstantego Jelskiego do Władysława Laskowicza - interesujący dokument dla historii polskich badań przyrodniczych końca dziewiętnastego wieku

The article presents an unpublished letter of naturalist and traveller, Konstanty Jelski to Władysław Laskowicz, an activist of the Polish political emigration in Paris. The letter draft the visit in Europe of Ignacy Domeyko, a Polish geologist who worked in Chile. Jelski feared the Russian 's oppressions after the patriotic expositions of Domeyko in Paris. In this letter Jelski mentions also His studies on silex of Poland and His its notes of a stay in Turkey. The letter provides valuables informations on the biography of Konstanty Jelski, one of more important explorer of the nature of South America.