In linguistic research of the 19th century there is still a lot to examine as far as the development of Polish is concerned. The article is an attempt of a synthetic presentation of major processes and phenomena which contributed to the evolution of Polish linguistic system in that century. 30 main processes with a distinction into phonetics (5), inflection (4), syntax (10), word formation (5), vocabulary (6) have been presented here altogether, including crucial individual changes (which together makes 65). It allowed a definition of the hierarchy of these processes and basic tendencies in development of every subsystem, i.e. phonetics, inflection - a tendency towards simplification of the system; syntax - a tendency to clarification and functional differentiation of the elements of the system; morphology, vocabulary - a tendency to fill in the gaps in linguistic means. The description is based on the background of the structuralist methodology, adapted in this kind of analyses in numerous diachronic linguistic works by the author.