EN
This article concerns the manuscript Roślin potrzebnych by Krzysztof Kluk, an enlightenment priest and scientist from Podlasie, an author of botanic and zoological guidebooks. The manuscript of his first botanic handbook was recently found in Baworoscy’s Library in Lviv. Nevertheless, considering lack of direct authorship mark, an analysis focused on graphic and phonetic linguistic features has to be performed to confirm the authorship. Studies have shown some linguistic features, which have as much in common with 18th century Eastern Borderland Polish Language (especially the northeastern). Other linguistic features have much in common with the dialects of Mazowsze and Podlasie. It is very likely that the manuscript has been written by someone who lived on the borderland of Mazowsze and Podlasie. According to Kluk’s biography it is almost certain this person was Krzysztof Kluk. Therefore, the manuscript discovered in Baworowscy’s Library is Krzysztof Kluk’s autograph with all probability.