She was the last woman to be publicly hanged in Dorset, as witnessed by Thomas Hardy - but little was known about her, until now...

"I REMEMBER what a fine figure she showed against the sky as she hung in the misty rain and how the tight, black, silk gown set off her shape as she wheeled half round and back."

Thomas Hardy was 86 when he wrote those haunting words recalling the public hanging of Martha Brown that he had witnessed in Dorset when a boy of 16. For 70 years could not exorcise the memory of her execution from his mind.

Martha was the last woman to be publicly hanged in Dorset, meeting her sudden end on the gibbet beside the gaol at Dorchester in August 1856.

And somehow enigmatic Martha tantalises everyone who tries to find out more about her life and horrible death.

Dorset author Rosemary Ellerbeck, who has written many best-sellers under the name of Nicola Thorne, is the latest to come under Martha's spell.

This year she published a novel based on Martha's deeply tragic life called My name is Martha Brown, fleshing out, through her imagination, the character of this fascinating woman who was born in obscurity and died so brutally, watched by thousands, at the end of the hangman's rope. It comes out in paperback on November 20.

And on the same day she is also publishing her own scholarly book, telling the fascinating facts uncovered in her research into the life of a woman who one night struck her husband with a hatchet then spun a lie that may have cost her her life.

Rosemary's quest began three years ago when a cameraman called Nick Gilbey asked her if she fancied doing a script for a television programme on Martha's story.

She did and made her first tentative inquiries, asking former Echo reporter Roger Guttridge who had written a chapter on the hanging in his book on Dorset Murders, if he had any more information that might help her.

"He told me people did not even know her maiden name. She was a person of great mystery which intrigued me," she told me at her home in Sturminster Newton, the town where Hardy himself once lived for two years.

Rosemary was hooked. Since then she, together with Nick and Swanage researcher Graham Chester with whom she swapped findings, gradually uncovered details of Martha's hard and intriguing life.

"Nick had an obsession about Martha as had Graham. And so, eventually, did I," she confessed.

The starting point was Martha's trial that took place just 18 days after the killing of John Brown. From there Rosemary started to work back, discovering that Martha had been widowed before marrying John and, through diligence, unearthing the name of her first husband.

No one yet has found out where Martha was born. But other facts have been revealed which almost bring the murderess back to life. She was probably born somewhere in West Dorset around 1811 although even the year is not certain. What is known is that her father was a dairyman, John Clark, married to Martha Clark. Martha Clark gave birth to many children over more than two decades including John, Richard, Ann, Robert, Mary, Thomas, William, Hannah (born 1810), Elizabeth (born 1819) and Charles. But there is no mention of a baby Martha. Perhaps she was illegitimate.

At the age of 20, however, the young Martha, who later in her life also went by the name of Elizabeth, married at Powerstock, Dorset on the day after Boxing Day in 1831. Her husband was Bernard Bearn, some 19 years her senior. He was a butcher and, for a year or so, a member of the vestry at the church in Powerstock. The couple lived at Meadways, a property with an orchard that can be found marked on an old tithe map at the public county records office.

Tragically, the couple's two children, William and Thomas, died in the space of two weeks at the ages of two and 12 months. The causes of their deaths are unknown. Within seven months James, the 11-year-old son of Bernard (whose first wife died in childbirth) also passed away.

At the time of her marriage Martha signed her name with a cross but Rosemary Ellerbeck believes that Bernard taught her the rudiments of writing, for by 1841 she was signing her own name as a witness at her sister's wedding. Rosemary does not know what became of Bernard, although there is one record of a death in a Hampshire workhouse that might, perhaps, be him.

What is known is that by 1851 she was a widow and living for 10 years as a housekeeper at remote Blackmanston Farm near Steeple, by the side of a beautiful Purbeck hill. The farm still stands today.

Mysteriously, the census lists her name as Elizabeth Barnes, a confusing fact that hampered Rosemary and other researchers, launching many a false trail.

The farm was owned by John and Robert Symes and Rosemary believes that Martha might have lived in one of the attic rooms, correctly away from the unmarried brothers who were close to her in age.

Fatefully, it was at Blackmanston where Martha came to meet the man she would come to love and kill.

Young John Brown, known to be nearly six feet tall, came to work there as a shepherd and fired what must have been a curious but fatal attraction. They married in Wareham register office in 1852 when she claimed to be 37 and he just 21. (During her research Rosemary insisted on seeing Martha's marriage certificate from the public records and discovered Martha had signed herself Elizabeth Bearn or Bearnes, not Barnes, thus, pivotally, opening a door to her past.)

Not long afterwards Martha and her young husband (some speculated he was after her £50 savings) moved to the hamlet of Birdsmoor-gate in Dorset's Marshwood Vale where she opened up a little grocer's shop and he bought a cart to set up business as a tranter. They also cared for a mysterious child, the illegitimate offspring of one of Martha's relations, about whom nothing else is known. Their move was to have terrible consequences.

Nearby another little shop was run by Mary Davis, the attractive wife of another man ... and tongues were soon wagging about the relationship between John and Mary.

On the day of the murder in 1856 John, who liked a drink, gave a lift to Mary on his cart and Martha got to hear of it. She cooked him supper and waited until he came home in the early hours.

By dawn he was dead.

Martha ran to fetch help, claiming his horse had kicked him by a field 200 yards away although no blood was found on the road. A doctor later said his head injuries were so severe he could not possibly have walked back home.

Even so Martha stuck to her simple story, bought mourning clothes from Crewkerne for the funeral and attended the inquest held at a nearby pub.

Within just three weeks she was standing in the dock at Dorchester Crown Court where the Tolpuddle Martyrs had once stood before, being tried for her life.

The case had been rushed into the Quarterly Assizes ("she was regarded as an unimportant peasant woman," said Rose-mary) where her calmness was seen as callous by those in court. The likelihood is she was in a state of shock.

Almost inevitably her story ("the lie of a child," says Rosemary), was not believed and the judge donned the black cap to sentence her to death. Only Blackmanston farmer, John Symes, spoke up in her defence. He had always found her, he said, a "kind and inoffensive woman."

Her late husband's father and sister visited her in prison - they must have felt some affection for her, says Rosemary - but petitions calling for a reprieve failed. There was so little time.