Queen of the Wits: A life of Laetitia Pilkington, By Norma Clarke

Betrayal, assault, destitution, abuse – nothing daunted this diminutive Grub Street hack

Laetitia Pilkington was tiny. Jonathan Swift, having made her remove shoes and stockings, stood her against a wall, pressed heavily upon her head and announced that she measured three feet two inches. Even allowed to stand up straight, she barely reached four feet, and her husband wasn't much taller. Both were clever and poetically inclined: both – temporarily – amused the author of Gulliver's Travels. He dubbed them "Mighty Thomas Thumb" and "Her Serene Highness of Lillyput".

A powerful, whimsical and casually malicious man, Swift raised the Pilkingtons high before dropping them. He described Laetitia as "the most profligate whore in either kingdom", and attempted to erase all mention of her from his writings. But she was not so easily beaten and her memory was sharp. Her robust and revealing anecdotes about the Dean of St Patrick's were to become the cornerstone of her fame.

The three portraits of Laetitia in the National Portrait Gallery all define her as "Adventuress". The best, by Richard Purcell after Nathaniel Hone, shows her with dangly earring, shiny nose, saucy half-smile and her dress inadvertently sliding down her shoulder. She certainly has an adventurous look but, as this meticulously researched and thoroughly enjoyable biography demonstrates, she was also brave, resourceful and very much cleverer than most of the idle layabouts with whom she was forced to consort.

Born in about 1708, the daughter of a respected surgeon, Laetitia grew up in Dublin and was married at 16 to a curate. She gave birth to six children, of whom three survived. Letitia's husband, hungry for money, began paying court to the rich and buxom Widow Warren, a character seemingly straight out of Sterne. The curate set a trap. One night, as Laetitia was reading in her bedroom with a handsome young doctor, he burst in unannounced with 12 armed night watchmen. She was turned out of the house at 2am, and stripped of possessions and children.

There may be another aspect to this story. The doctor was phenomenally dashing: subsequently an Earl's daughter had only had to glimpse him to be overwhelmed by "singular, sudden and violent" emotions. It is possible that he and Laetitia were not only reading. Properly partial as Norma Clarke is, she is not naïve. Besides, as she comments: "It would be nice to think that she had a bit of rapture before it all went so horribly wrong."

Thoroughly disgraced and virtually destitute, Laetitia sought her fortune in London where, helped by influential contacts, she took lodgings in St James's opposite White's Club, from which vantage point she could observe the members, and they her. She was watering her flower-pots one day when several noblemen toasted her. She quickly took up her pen and wrote: "Your rosy Wine /Looks bright and fine;/ But yet it does not chear me:/ The Cause I guess/ is surely this:/ The bottle is not near me". A club servant was instantly dispatched, bearing a brimming glass; she returned the toast. But in Georgian London such wit was not enough. She was repeatedly insulted, robbed, assaulted and eventually imprisoned for debt in the horrible Marshalsea gaol.

Twice she came close to suicide, yet her magnificent spirit and fierce intelligence brought her back to the fight. Describing herself as "naturally liberal and no very great Oeconomist", she was unfailingly generous and increasingly outraged by the fate of women who, like herself, were punished for "crimes" which went unnoticed, even praised, in men.

She was not your common courtesan. She was a ghost-writer, a gifted Grub Street hack. She wrote, to order, poems, petitions and billets-doux; sermons, prologues and memorials; apologies, elegies and epitaphs "on any subject except the law". Many of these were lost or stolen – at one stage, her daughter Betty turned up (pregnant and unmarried) and used some of them to light the fire – but enough survive to demonstrate her sparkling and enduring perceptiveness. Best of all, the three volumes of her Memoirs are a prototype for every racy, gossipy autobiography written since – and much better than most.

Google gives her 28,000 mentions; Virginia Woolf wrote an essay in her praise; one of her poems adorns the London Underground. Now, at last, she has the biography she has long and richly deserved.