An unknown source of biographical data about the family of A. M. Dostoevsky, younger brother of the writer

The article introduces into scientific discourse an unknown source of biographical data about the family of A. M. Dostoevsky, younger brother of the writer. It is a commemorative edition of a family menology in Church Slavonic dated back to 1849 and kept in the Literary-Memorial Museum of F. M. Dostoevsky in St. Petersburg. On its margins in front of the corresponding dates Andrei Mikhailovich placed records about family events, such as birthdays, baptismal ceremonies, weddings and deaths of his children, the writer's nephews and nieces. The author of the article considers the mentioned records as a primary source, even in regard to notorious memories of A. M. Dostoevsky. On the fly page of the calendar of months together with a provenance there is a record, made by an unidentified hand which testifies the fact of obtainment of the book by Andrei Mikhailovich from doctor F. P. Gaaz. The article makes an attempt to reconstruct the circumstance under which the writer's brother could meet a legendary “holy doctor”.