Last year, grammatical tragedy struck in the heart of England when Birmingham City Council decreed that apostrophes were to be forever banished from public addresses. To the horror of purists and pedants alike, place names such as St Paul’s Square were banned and unceremoniously replaced with an apostrophe-free version: St Pauls Square.

The council’s reasoning was that nobody understands apostrophes and their misuse was so common in public signs that they were a hindrance to effective navigation. Anecdotes abounded of ambulance drivers puzzling over how to enter St James’s Street into a GPS navigation system while victims of heart attacks, strokes and hit ‘n’ run drivers passed from this world into the (presumably apostrophe-free) next.

Why the confusion? Part of the reason is that apostrophes are not particularly common in the English language: In French they occur at a rate of more than once per sentence on average. In English, they occur about once in every 20 sentences. So English speakers get less practice.

But the rules governing apostrophes are also more complex in English. In both French and English, apostrophes indicate a missing letter, such as the missing i in that’s or the v in e’er. But in English, apostrophes also indicate the possessive (or genitive) case. They are used to show that one noun owns another: St James’s Street is the street belonging to St James.

The complexity is compounded because in English, the plural is often formed by adding an s. So the word boys means more than one boy. How then do you form the possessive to indicate, for example, a ball belonging to the boys? Is it the boy’s ball or the boys’s ball or the boys’ ball?

And then there are the exceptions. Pronouns, for example, do not take a possessive apostrophe: you can’t say I’s ball or me’s bat. The truth is that knowing when to use an apostrophe is not always easy.

That may be partly because the rules for using apostrophes are evolving. Today, Odile Piton and Hélène Pignot at the University of Panthéon-Sorbonne in Paris present an analysis of the use of apostrophes in English texts from the 17th century and show that the usage was much simpler in those days.

Their main challenge was how to recognize an apostrophe. Apostrophes are often the same as single quotation marks and are entered on a computer keyboard using the same key. So it’s easy to get false positives.

Spotting the absence of an apostrophe where there ought to be one can be tricky, too. They give the example of this sentence: “First, that no other mans errors could draw either hatred, or engagement upon me.” The automated analysis missed the absent apostrophe in mans, thinking instead that it was the transitive verb “to man.”

What Piton and Pignot have yet to study how the use of the apostrophe changes in time. But they now have the automated analysis tools that should make this possible. That could reveal the forces at work that change our language.

For the moment, Piton and Pignot’s conclusion is merely that the world was simpler in the 17th century as far as apostrophes go. They say: “The possessive genitive in ‘s was not very common yet. The apostrophe mostly marks the omission of letters in a wide range of words and the plural of certain words.”

Rather like the road signs in Birmingham.

Ref:arxiv.org/abs/1002.0479: “Mind your p’s and q’s?”: or the Peregrinations of an Apostrophe in 17th Century English