Golden Numbers
My entire project began based on the question, “What are those roman numerals on the left hand side?” I originally assumed they must have had to do with the date, yet it didn’t make any sense considering they were not in any kind of sequential order. Lucky for me, a peer of mine had stumbled upon Introduction to Manuscript Studies by Raymond Clemens and Timothy Graham, and this book had the answer I was looking for!
The roman numbers on the left hand side of the page are called “Golden Numbers”. These numbers are used in order to determine what day of the month the new moon would land on each month. These numbers are based upon the 19 year dysonian (metonic) cycle. This cycle is derived from the idea that although there are 365 days in a solar year, there are only 354 days in a lunar year (Clemens & Graham, 2007)(Poole, 1921). Thus the beginning of the new solar year and the new lunar year did not always coincide, however every nineteen years these dates coincide again on January 1st. Thus much like the dominical letters discussed in the last section, each year would be assigned a Golden Number, and that number would be used each month in order to determine what day the new moon would land on. Many sources provided the following formula for determining the Golden Number:
(Year)+1=Total/19=(New Total) with a remainder of (Golden Number)
However, with the change from the Julian to the Gregorian calendar format in 1582, this formula is no longer valid for determining the years golden number. However it does seemto me, at least tentatively, that by making a small change to the formula we can still determine a year’s golden number:
(Year)+3=Total/19=(New Total) with a remainder of (Golden Number)
So if we were to attempt to figure out the Golden number for 2015
(2015)+3=2018/19=106 with a remainder of 4.
So the Golden number for 2015 would be four, and according to UCR 013V, for the month of April the new moon should land on the 18th (VIIII KL). Which with a quick google search can be easily confirmed.
Calendar-12. (n.d.). Dates of Moon Phases in 2015 Year. Retrieved from http://www.calendar-12.com/moon_phases/2015
These numbers were also used in order to determine what date of the year Easter would land on. Easter lands on the Dominica(Sunday) following the first full moon after the beginning of spring (Clemens & Graham, 2007). So let’s see if we can figure out what day Easter should have landed on this year according to UCR 013 (R&V). In 2015, the first day of spring landed on March 20 (VIII KL according to this calendar). We have already determined that the Golden Number for 2015 was 4, so then the new moon for March also happens to land on the 20th (VIII KL). In order to find the date of the full moon we need to add 14 days to the day of the new moon, this lands us on April 3rd (III NO). We also determined in the previous section that the Dominical letter for 2015 was “D”, thus the Dominica(Sunday) following the first full moon after the beginning of spring would be the 5th of April (I NO). Again this can be confirmed with a simple google search.
Time and Date AS. (n.d.). Easter Sunday in United States. Retrieved from Time and Date: http://www.timeanddate.com/holidays/us/easter-sunday
Now that you understand how to read Medieval Calendars, it’s time to put that knowledge to the test!
Let's check out some mistakes in time!
Source(s):
Clemens, R., & Graham, T. (2007). Liturgical Books and Their Calendars. In R. Clemens, & T. Graham, Introduction to Manuscript Studies (pp. 192-207). New York: Cornell University Press.
Poole, R. L. (1921). Medieval Reckonings of Time. (C. Johnson, & J. Whitney, Eds.) New York, New York: The MacMillan Company