(en) The article deals with certain facts of life and scientific achievements of Joseph Lang, the graduate of the Law Faculty of the University of Freiburg (1775/1776–1820), who taught economic and financial disciplines in Kharkov University during 1805–1819 years. It is analyzed little-known to a broad scientific audience artistic heritage of the scientist, including the author’s model of social reproduction. In this model the general economic financial calculation is presented as static models of economic equilibrium, it is attempted to develop the integrated matrix of financial flows and to compare the economy of the then Russian Empire to the economy of European countries.