As probatio pennae , a spring sample , referred to the handwritten traces that a writer has left practicing with pen and ink. Such traces are not infrequently found in old manuscripts or as marginalia on the unprinted margins of earlier printed works as well as on their unprinted pages and endpapers .
Most of the time the scribes tried the swing of the pen with the words and characters they needed in their manuscript; in some cases literary evidence was passed on through such finger exercises, for example some verses from the poor Heinrich des Hartmann von Aue . The feather test Hebban olla vogala , discovered in England in 1933, is considered to be the earliest surviving written record of the Old Dutch language.
- Fritz Funke: Book customer. An overview of the history of books and writing . Munich-Pullach, 1969; P. 47