Nicolas stayed there until 1792, working as Adam's personal assistant and possibly tutoring his children: Henryka (b. 1777) and Mikolaj (b. 1783). His friends from this period included Jakub Benik (24 July 1772 Dobre Miasto, Warmia - 20 January 1827 Warsaw) and Jan Austen (early 1774 Wilkie, Warmia - 6 May 1828 Warsaw), a professor at the Elementary School of Artillery and Engineering (Szkola Elementarna Artylerii i Inzynierów) for the Army of the Duchy of Warsaw.