If Today Is Sunday, This Must Be 1798

A section of a diary kept between 1797 and 1800 by the Quaker farmer Jacob Peirce recently joined the collections of the Penn Libraries as Oversize Ms. Codex 2079, thanks to the Philadelphia Society for Promoting Agriculture.  Peirce was a busy man, but he found time to write brief entries about the work of the day on his farm, visits with family and friends, his health, and the weather. He also recorded his attendance at meeting for worship with a handful of Quaker meetings in the Brandywine Valley.  His grandfather, George Peirce, had purchased 402 acres from William Penn’s commissioners in 1700.  This land passed to Jacob’s father and was subsequently inherited by Jacob and his two brothers, who on their part of the land started the arboretum that was a predecessor of Longwood Gardens.

Photograph of Old Kennett Meetinghouse, Kennett Square, built by 1731, where Jacob Peirce and Hannah Buffington married in 1767 (Library of Congress Prints and Photographs Division, HABS PA,15-KENSQ.V,4–33 (CT)).

In his diary, Jacob followed the traditional Quaker practice of using numbers for the months of the year and the days of the week, rather than their names, which early Quakers had deemed to be pagan in origin.  The section of Jacob’s diary now at Penn begins in 1797 on “11^th month 24^th” – November 24^th.  On my first pass through the entries for 1798, I noticed that dates when Jacob went to meeting for worship – Sundays — were consistently marked in the left margin with a symbol, which looked like the letter G.  But why G?

Detail from Jacob Peirce’s diary (Oversize, Ms. Codex 2079, f. 3r, detail), showing the year 1798 at the top of the page, his abbreviation for “First Month” to the left of the 20th, and the letter G to the left of the 21st and the note, “went to meeting.”

Detail from Rouen book of hours (Ms. Codex 1056, f. 1r, detail), showing the beginning of the month of January. The dominical letters are in the second column, starting with a small illuminated A, followed by the letters b through g.

When the year changed from 1798 to 1799, Jacob’s “Sunday symbol” changed from G to F.  I realized then that these were dominical letters.  The history of dominical letters reaches back to the Roman calendar, but I’m familiar with their use in calendars in medieval liturgical and devotional manuscripts.  In the medieval calendars, the cycle of letters A-G are marked next to the days of the month.  In an A year, the dates with an A would fall on Sundays.  The purpose of the system was always to determine the day of the week for particular dates, but when Christians adopted the system, their particular focus was on where the Sundays would fall in a given year, a necessary piece of information for determining the date of Easter.  Hence “dominical letter,” from dominica, the Latin name for Sunday, the Lord’s day.  Each year was assigned a letter from A to G, and knowing that G is the dominical letter for 1798 means that January 7^th is the first Sunday of the year, as indeed it is marked in Jacob’s diary.

January page from Briggs’s Maryland, Pennsylvania & Virginia Almanac for 1798 (Rare Book Collection AY196.B2 B744, f. 4r, detail). The first column tracks the days of the month, the second the days of the week. As the 7th was a Sunday marked G, the 21st was as well.

Now I had a different question:  what was the source of the dominical letters in Jacob’s diary?  I hadn’t recognized them at first, because I never expected to see them there.  The answer turned out to be almanacs.  These popular annual publications routinely included the dominical letter of the year in their general information about the year, as well as showing the dominical letter in their calendar pages, much as the medieval calendars did, but in a way that only applied to the year for which the almanac was published.  It’s fascinating to see this bit of calendar technology not only surviving a transition from manuscript to print, as it did through at least the middle of the 19^th century, but also passing from ancient Romans to medieval Catholics to a Quaker farmer in the new United States.