When Willem Bartjens, school teacher from Zwolle, wrote the closing lines of his arithmetic book De cyfferinge, little did he know that he had just produced a bestseller. For two centuries, the booklet and its successor De vernieuwde cyfferinge would be used extensively in Dutch arithmetic education. It was not until the nineteenth century that the textbooks became outdated. By that time, however, master Bartjens had already reached immortality; to this day, he lives on in the Dutch expression 'accoring to Bartje(n)s', meaning 'logical'.

The 1753 edition of De vernieuwde cyfferinge is one of the striking objects from the children's books and prints collection of the Stadsarchief en Atheneumbibliotheek Deventer (Deventer municipal archive and athenaeum library). A broad selection of fine objects from this collection can now be accessed online via the Memory website.