EN
Henryk Hoyer (1834–1907) entered the history of Polish medicine as an outstanding histologist and physiologist. After medical studies in Wrocław and Berlin, he eventually settled in Warsaw, taking over, in 1859, the chair of physiology and histology at the Warsaw Medical-Surgical Academy, transformed into the Medical Faculty of the Warsaw Main School, and later into the Imperial University of Warsaw. Polish histology owes much to Hoyer: he established the first histological and physiological laboratory on the Polish territory, becoming the first Polish histologist. He also published the first Polish histology textbook, introducing new scientific terminology into Polish. The article is a critical analysis of the book chapter of Histologia ciała ludzkiego (“Histology of the human body”) devoted to nervous tissue. The work reflects the concepts of microstructure and function of the nervous system that prevailed in the mid-19th century. The author was clearly inclined towards the reticular theory which emerged at the time, however in all honestly he left many issues as open questions. Hoyer’s work deserves special attention, because it gives an insight into the state of knowledge, but also into the way of reasoning of the 19th-century pioneers of physiology and histology.