A number of Czech language volumes from the medieval era on the subject of medicine have been preserved, stored in domestic and foreign library collections. One of these is the manuscript from the middle of the 15th century, located in the Czartoryski Library in Cracow with the call number B 1497. The volume is a compilation and contains therapeutic texts, treatises on plants and stones, and other specialized treatises. This article describes the content of the volume in detail, though attention is devoted above all to the characteristics of language at all levels. Of exceptional interest is the vocabulary used - the volume documents lexical units which are not documented in other sources or are documented negligibly or with different meanings. There is detailed commentary on the relationship of this volume to the manuscript with the call number II H 4 in the Library of the National Museum in Prague, which is a copy of the Polish manuscript.