The Reckoning of Time


‘The Reckoning of Time’ was a very influential work composed by the monk Bede (d. 735) in 725. This manuscript is one of nearly fifty surviving copies. It was made in the 11th or 12th century, probably in the region that is now France, judging from its script and decoration, and the way its parchment was prepared. Bede’s text is found here alongside many other texts on mathematics and astronomy, including Bede’s earlier scientific treatises De natura rerum (‘On the Nature of Things’) and De temporibus liber (‘On Times’) composed in 703, as well as diagram of the planets’ orbits by Abbo of Fleury (d. 1004) and Cicero’s (d. 43 BCE) poem on the constellations. This book contains a number of illustrations and diagrams, including a diagram showing the Roman method of counting to 10,000 and beyond with your fingers.

‘The Reckoning of Time’ deals with computus, the science of time-reckoning and how to calculate the date of Christian holy days such as Easter. Composing the text for his pupils at Wearmouth-Jarrow, Bede used similes to communicate abstract ideas. Explaining that that Earth is shaped like a sphere, Bede said that it is ‘not circular like a shield or spread out like a wheel, but resembles a ball being equally round in all directions’. Because it was so clearly written, with examples for teachers and pupils, De temporum ratione became one of Bede’s most popular works, remaining a core ‘school book’ in western Europe for centuries.

This manuscript was digitised with the support of The Polonsky Foundation.

Full title:
Miscellany works on computus and astronomy
11th century–12th century, England or France
Usage terms

Public Domain in most countries other than the UK.

Held by
British Library
Royal MS 13 A XI

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