The source of all the confusion in Oscar Wilde’s 1895 play The Importance of Being Earnest is a lost manuscript. Miss Prism’s self-penned three-volume novel, in fact. Despite it being a fictional work, this literary treasure has raised unanswered questions for serious scholars of Wilde. (Oh, fine then, just me.)

When we meet Jack Worthing, the protagonist of the play, he is pursuing unsuccessful matrimonial ambitions. He wants to marry Gwendolen Fairfax but is failing on two counts. One: Gwendolen will only marry a man named Ernest (“a name that inspires absolute confidence”). Two: His parentage has not proved sufficiently sophisticated to win the approval of Gwendolen’s mother, Lady Bracknell. Instead of being able to intimate that he will inherit an estate in Shropshire, for example, Jack’s antecedents are uncertain. As a baby, he was found in a handbag in the cloakroom at Victoria Station (the facility for the Brighton Line).

Upon the arrival of the governess, Miss Prism, Jack’s antecedents become more apparent. Miss Prism, Lady Bracknell informs us, left Lady Bracknell’s sister’s house 28 years ago in possession of a baby in a perambulator. Neither Miss Prism, the perambulator, nor the child returned. “Prism!” Lady Bracknell demands to know. “Where is that baby?”

The wretched Miss Prism is forced to confess that she had confused the baby in her charge with a manuscript, a work of fiction that she had composed during her (few, she mentions) unoccupied hours. One item was to go in a capacious handbag suitable for the transport of many leaves of paper, the other in the perambulator. “In a moment of mental abstraction, for which I never can forgive myself,” says Miss Prism, “I deposited the manuscript in the basinette, and placed the baby in the handbag.”

The handbag, of course, she had left at a cloakroom at Victoria Station (the Brighton Line). (People are always leaving manuscripts at train stations; they just can’t help it.) Immediately, Jack is revealed to be the lost baby, the son of Lady Bracknell’s sister, Mrs Moncrieff, and therefore acceptable breeding stock after all, as well as happily restored to his kin. Also, hey presto! Turns out his given name really is Ernest, after all. So that’s the marriage with Gwendolen sorted.

Miss Prism’s novel (“of more than usually revolting sentimentality”, according to Lady Bracknell) was discovered at midnight, still in the perambulator, standing by itself in a remote corner of Bayswater.

We know little about Miss Prism’s history. We know, according to the scars on her handbag, that she was involved in (as a very early suffragette, perhaps?) “the upsetting of a Gower Street omnibus in younger and happier days”. We also know that she chose to deposit the handbag containing the baby at the rather more fashionable side of Victoria Station.

The east side was the home of the London, Chatham and Dover Railway and its platforms. To the west lived the more upmarket London, Brighton and South Coast Railway — the Brighton Line — from which one could travel to Worthing, the flourishing seaside town to which the gentleman who found lost baby Jack was travelling (and after which resort the boy was temporarily named).

The distinction remains today. You can ask cabbies to drop you at the Brighton Line, and they will make their way unerringly to the station entrance in Buckingham Palace Road, steering clear completely of the Eastern proletariat trains for commuters to Gravesend and beyond.

Still, I wonder about Miss Prism. What could have caused such a monumental moment of misperception in Victoria Station to deposit an infant in a fashionable left-luggage office and take a stroll around London with a bundle of paper dripping with sentiment?

Above all, what was she doing in Bayswater? It is an indeterminate district, unsure even of its postcode at times. What further nefarious actions, perhaps involving more omnibuses, could have caused this upright governess to abandon her perambulator in darkness?

The play leaves this rich field unharvested. As, upon reflection, do I. Instead, I like to think that Miss Prism married the Reverend Chasuble and they took the train to Worthing and pioneered the caravan park.