Slashes (Virgules) & Dates


9 March 2014

In common usage, we often see slashes (virgules) used in dates—e.g., 1/5/1777 or 1 March 1747/48. Like many punctuation marks, this one is covered by rules that seem nit-picky until we learn the rationales behind them.

In taking notes from historical sources, using the 1/5/1777 format as a quick way to write dates is a quick path to a problem. While the U.S. convention is to write month/day/year, many historic records follow a more universally common practice of day/month/year. If we write 1/5/1777 in our notes, then when we later come back to these notes we'll be left wondering whether the date was 1 May 1777 or January 5, 1777.

The second example above, 1 March 1747/48, is frequently seen in notes or abstracts from records of the colonial era when "double-dating" was a custom. For a century or so before 2 September 1752, England and her colonies used the Julian Calendar (beginning 25 March) for some functions and the Gregorian Calendar (which began on 1 January) for other functions. As a consequence, dates between 1 January and 25 March were often "double-dated" in a fashion that cited both the outgoing and incoming years—i.e., 1 March 1747/8.

The nitpicky rule to remember here is this: In instances of double-dating, only one digit follows the slash. Yes, in every-day usage we "shorten" four-digit years to two digits, but writing a double-date situation as 1 March 1747/48 is a sin against clarity. The correct form—the one that proclaims to the world, "Hey, I'm a double-dated document!"—would be 1 March 1747/8.

For a fuller discussion of slashes and dashes see EE 2.75.

dpalamedes's picture
Dating confusion - thanks for the post

Appreciate the explanation.  As a Canadian, I have to stop and ask myself about dates when I see anything from the US.  We use the day/month/year format.  Virgules to many of us (because of the French influence) mean "commas". 

Re Julian vs Gregorian, many countries continued to use the Julian into the 20th century.  My father was born in Greece in 1917, under the Julian calendar and when he came to Canada had his official birthdate adjusted.  So, when I do research in Greek records, I have to remain alert to which calendar it was under, as it changed in 1923.


EE's picture
DenaP,  your last line is the

DenaP,  your last line is the money line for all of us. Wherever we work, we have to learn the context, culture, and practices of that place and time.


The Editor

dsliesse's picture

For the benefit of those without the book (or, like me, who are somewhere the book isn't), would it be safe to assume the usual exception for the case of the second year changing the tens digit?  In other words, one would write 1749/50 instead of 1749/0?

EE's picture
Yes, indeed, Dave. For

Yes, indeed, Dave. For clarity, we would write 1749/50—not 1749/0.


The Editor

centavo's picture
Something I don't understand about double dating

I understood from what I read some time ago that double dating applied to both the year and the day for those dates between January 1 and March 25 because of the addition of 11 days to the Gregorian calendar.  Is this correct?  If I've come across any instances of double dating of the day, it's been rare enough that I don't remember it.