moment (unit)
{{Short description|Medieval unit of time}}
{{redirect|Moment (time)|a point in time|Instant}}
File:CLM 14456 71r detail.jpg and of the week, from a Carolingian {{abbreviation|ms.|manuscript}} (Clm 14456 {{abbreviation|fol.|folio}} 71r) of St. Emmeram Abbey. The day is divided into 24 hours, and each hour into 4 {{lang|la|puncta}}, 10 {{lang|la|minuta}}, or 40 {{lang|la|momenta}}. Similarly, the week is divided into seven days, and each day into 96 {{lang|la|puncta}}, 240 {{lang|la|minuta}}, or 960 {{lang|la|momenta}}.]]
A moment ({{lang|la|momentum}}) is a medieval unit of time. The movement of a shadow on a sundial covered 40 moments in a solar hour, a twelfth of the period between sunrise and sunset. The length of a solar hour depended on the length of the day, which, in turn, varied with the season.{{cite book|last1=North|first1=John David|title=Chaucer's Universe|date=1988|publisher=University of Michigan Press}} Although the length of a moment in modern seconds was therefore not fixed, on average, a medieval moment corresponded to 90 seconds. A solar day can be divided into 24 hours of either equal or unequal lengths,{{cite book|last=Bede|title=The Reckoning of Time|publisher=Liverpool University Press|url=https://books.google.com/books?id=yFsw-Vaup6sC&pg=PA267|page=267|access-date=23 January 2017|isbn=9780853236931|year=1999}}{{cite book|last1=Bacon|first1=Roger|title=Opera quaedam hactenus inedita|publisher=Oxford University Press|url=https://archive.org/stream/p6p7operahactenu00baco#page/n78/mode/1up|page=45|access-date=5 July 2014}} the former being called natural or equinoctial, and the latter artificial. The hour was divided into four {{lang|la|puncta}} (quarter-hours), 10 {{lang|la|minuta}}, or 40 {{lang|la|momenta}}.{{cite book|last=Bede|title=The Reckoning of Time|publisher=Liverpool University Press|url=https://books.google.com/books?id=yFsw-Vaup6sC&pg=PA268|page=268|access-date=23 January 2017|isbn=9780853236931|year=1999}}
History
The unit was used by medieval computists before the introduction of the mechanical clock and the base 60 system in the late 13th century. The unit would not have been used in everyday life. For medieval commoners, the main markers of the passage of time were the call to prayer at various intervals throughout the day, and the passage of the sun.{{Cite web |date=2015-07-29 |title=How Did People in the Middle Ages Tell Time? |url=https://www.huffpost.com/entry/how-did-people-in-the-mid_b_7892318 |access-date=2025-06-20 |website=HuffPost |language=en}}
The earliest reference found to the moment is from the 8th century writings of the Venerable Bede,{{cite book|last=Bede|title=The Reckoning of Time|publisher=Liverpool University Press|url=https://books.google.com/books?id=yFsw-Vaup6sC&pg=PA15|page=15|access-date=23 January 2017|isbn=9780853236931|year=1999}} who describes the system as 1 solar hour = 4 {{lang|la|puncta}} = 5 lunar {{lang|la|puncta}}{{cite book|last=Bede|title=The Reckoning of Time|publisher=Liverpool University Press|url=https://books.google.com/books?id=yFsw-Vaup6sC&pg=PA73|page=73|access-date=23 January 2017|isbn=9780853236931|year=1999}} = 10 {{lang|la|minuta}} = 15 {{lang|la|partes}} = 40 {{lang|la|momenta}}. Bede was referenced five centuries later by both Bartholomeus Anglicus in his early encyclopedia {{lang|la|De Proprietatibus Rerum}} (On the Properties of Things),{{cite book|title=Middle English dictionary|publisher=University of Michigan Press|url=https://books.google.com/books?id=4jah7UrsrvQC&pg=PA644|page=644|access-date=5 July 2014|isbn=978-0472011360|date=1977-12-31}} as well as Roger Bacon,{{cite book|last1=Bacon|first1=Roger|title=Opera quaedam hactenus inedita|publisher=Oxford University Press|url=https://archive.org/stream/p6p7operahactenu00baco#page/n81/mode/1up|page=48|access-date=5 July 2014}} Note the distinction between {{lang|la|minucia}} and {{lang|la|minuta}}, as well as the introduction of the {{lang|la|ostenta}}, the precursor to the modern minute. by which time the moment was further subdivided into 12 ounces of 47 atoms each, although no such divisions could ever have been used in observation with equipment in use at the time.
References
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{{Time measurement and standards}}
{{Time topics}}
{{wiktionary|moment}}