Bede’s horologium

This essay aims to establish the Venerable Bede’s place in the history of medieval astronomy by examining certain frequently cited passages that suggest that he and other monks in early eighth-century Northumbria measured the date of the vernal equinox by means of a sundial or horologium. These references must be located in the context of ongoing controversies between the ‘Roman’ and ‘Celtic’ parties in the British Isles, who followed diverging conventions for calculating the time of Easter and located the vernal equinox on different dates. While it is indeed possible to identify instruments and methods that may have served Bede in supporting his case for the ‘Roman’ equinox on 21 March, the historical significance of his appeals to horologica consideratio lies primarily in their reception by subsequent authors, who took from Bede the notion that observation was a legitimate way of validating computistical doctrines. This line of influence culminated in the frequently overlooked work of William of Hirsau (before 1069), who employed innovative observational techniques to establish new conventions for the dates of the equinoxes and solstices, thus providing us with a crucial link between the early medieval computus tradition and the assimilation of Arabic astronomical knowledge during the eleventh and twelfth centuries

Ancient history · Archaeology · Astronomy · Context (archaeology · Eleventh · Epistemology · Equinox · Geodesy · Geography · History of science · Observational astronomy · Physics · Solstice · Classics · Historical and Linguistic Studies · Historical Astronomy and Related Studies · Historical, Religious, and Philosophical Studies · History · Philosophy

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