Vovelles
Although paper dials had been used for centuries to illustrate complex ideas, the first known use of them in early printed books was by German mathematician and astronomer Johannes Müller von Königsberg (1436 – 1476). Also known as Regiomontanus, he included four paper dials in his works on astronomical calendars ca. 1476.
Moveable dials called vovelles first appeared as woodcuts in the late 15th century. They were made popular by German mathematician and geographer Peter Apian (1495 – 1552) in his work Cosmographia (1524), which included volvelles by Dutch instrument-maker Gemma Frisius (1508 – 1555). This is just one of many examples of vovelles in the Bell Library collection, from a 1551 edition of Apian's Cosmographia. Bell shelf mark 1551 Ap.
