Abstract
Prague Nostitz Library hides among its 14 000 books 60 volumes from the library fragment once belonging to Matthias Stoius Jr (1526-1583), the personal physician of the first Duke of Prussia Albert of Hohenzollern. The most interesting volume from the Stoius's heritage is a copy of an astronomical calendar Almanach novum by Pietro Pitati used by Stoius as a diary containing his handwritten notes and comments about weather, income, his activity at the Königsberg University and, the most importantly, his medical records concerning the health condition and problems of his noble patient Albert of Hohenzollern.
Stoius also took detailed notes about medicaments he delivered to the ill Duke as well as about treatments he applied especially in November 1559 and December 1560 when the physical condition of the duke of Prussia apparently worsened. In 1572, Stoius published in print his report about the last days of Duke Albert and although the handwritten sources on which the report is based are missing they were presumably recorded in the similar diaries.