Medieval Apps

In the later Middle Ages various tools were added to bound books that made the books more interactive. These tools served a variety of purposes: some clarified the text’s meaning, while others functioned as a calculator or allowed the reader to tell time. The volvelle, the cogwheel and the sundial are three examples.

Volvelles are paper wheels that were fastened to a page so that the discs spin independently. People used them to perform calculations or to gain additional information through the rotation of the pieces.

Volvelle - British Library, Egerton MS 848 (15th century) – Source

Cogwheels were fitted into a space in the binding. Turning these produced the number that could subsequently be looked up in the table.

Cogwheel-Oxford, Bodleian Library (14th century) – Source

Sundials were stamped or pasted on the book. The reader could put the book in the sun and place a stylus on the cover and use it to tell time. 

Sundial - Oxford, Bodleian Library,(17th century) – Source

"Just like our modern smartphones, the medieval book could be a versatile tool that combined contents with an untold number of applications – giving the scriptorium the feel of an App Store."

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