An attempt to create a written Mongolian language based on the Cyrillic script is linked to the missionary activities of Archbishop Nil (1799-1874) among the Buryat Mongols. On his initiative, several Christian liturgical books were translated into Mongolian and printed in St. Petersburg. However, Nil and his assistants did not take into account the discrepancy between written and spoken Mongolian language and transcribed every letter of the Mongolian written language with corresponding Cyrillic letters and thus did no in any way make the texts closer to the spoken language.

The holdings of the Kórnik Library include a book of abstracts of lawsuits concerning the boundaries of estates in Greater Poland in the 15th–17th century, written in Latin. Its presumed author, the otherwise unknown Piotr Biernacki, had the ability to write in both the Latin and the Cyrillic alphabet. This article focuses on the reading and the palaeographic and linguistic analysis of several Latin sentences, one heading and more than 20 margin notes written in the Cyrillic alphabet. The Cyrillic handwriting found in the book is a Russian skoropis used in Ukrainian areas of Poland in the 17th century. When writing the Latin text with the Cyrillic alphabet, the author utilised the Polish language of the time in the reading of Latin. The cryptograms found in the book have a technical/informative nature and do not contribute any significant information to the text. In combination with the fact that the Cyrillic alphabet was not at all used in Greater Poland, the above suggests that the author was playing with the reader, who was thus forced to look for the meaning of the incomprehensible text.