A first-class biography is usually born of a writer's personal urge to distort another person's life so that it makes a story. And after reading Miranda Seymour, I know the story I would tell of the life of Mary Shelley, the writer of Frankenstein. It is the story of how the "free love" ethos which she imperfectly understood to be that of her mother, the author of the Vindication of the Rights of Woman, Mary Wollstonecraft and her father, the author of Political Justice, William Godwin, crashed against institutional sexism and destroyed her life.
Mary Wollstonecraft died of an infection introduced on the hands of a surgeon after she gave birth to Mary Shelley. She was never able to explain to her second daughter what she had learned from being abandoned by the lover she had taken in revolutionary France, along with the little girl he had fathered; it is the same lesson which the women of the Flower Power generation learned: that there is, for women, no escaping responsibility in relationships if children become part of the equation.
The 16-year-old Mary Shelley didn't know that when she first made love with Percy Bysshe Shelley, on her mother's grave, in 1814. Otherwise, she would hardly have been able to disregard the existence of Shelley's pregnant wife, Harriet. The lesson was taught her savagely, soon, and then endlessly, however. Less than a year later, her own first baby, Clara, was born prematurely and lived for about a fortnight. It is astonishing that it took until the 1970s for the publication of a reading of Frankenstein like that in Ellen Moers's Literary Women - that it is the work of a woman whose own birth had killed her mother, and for whom becoming a mother had had horrifying consequences. She kept dreaming that Clara had come to life again "that it had only been cold and that we rubbed it by the fire and it lived . . ."
At this point, we see the beginnings of Mary's conservatism in her unsurprising refusal to contemplate a sexual commune made up of herself, her half-sister, Claire Clairmont, Shelley and his friend, William Hogg. However, she could not get rid of Claire: despite the silences in Mary's diary and the suppressions and elisions which have occurred down the years, Seymour seems fairly convinced that Claire and Shelley were lovers; certainly Claire lived with the happy couple for most of their life together, at Shelley's insistence.
She also speculates fairly strongly that Claire became pregnant once and perhaps twice by Shelley, and that while she lost one child, the other was Allegra, attributed to Lord Byron. There was also another child who was suddenly adopted by Shelley in Naples, and who may or may not have been his by another woman.
Mary's second and third children died in their infancy too, of different fevers, as Shelley dragged his entourage around Italy in the heat. The loss of her son William - she called him "Willmouse" - seems to have cracked Mary's spirit for good. Allegra died too, of typhus, in a convent to which Byron farmed her out; as a woman, Claire had no rights over her own child.
By 1822, Shelley was writing piteous letters and poems complaining of his wife's coldness. No-one seems to have considered the death of three children and a traumatic miscarriage as mitigating circumstances. After Shelley went to his death, his sail hoisted too high on a boat called the "Don Juan", Mary was cast as having blighted his life.
They had blighted each other's lives. Mary Shelley, then only 24, spent the rest of her life, like Frankenstein's Creature, as a social outcast, because she had had children with a married man, whose wife had then committed suicide. Her attempts to be readmitted to society were frantic and unremitting, mostly for the sake of her only remaining child, Percy. She had little choice: Shelley's father placed conditions on the payment to her of a miserly allowance, which included making no attempt to bring the late poet into the public eye, not publishing his work, not using his name in her own writings, and making no attempt at contact with the Shelley family.
Percy eventually inherited Sir Timothy's baronetcy and dismal estate, but he was a poor focus for Mary's vaulting ambition; the strongest vote we have in his favour is that of Robert Louis Stevenson, who called him "as honest as a dog".
Seymour herself doesn't so much tell a story, however, as present evidence. Bias there is, of course - this is the work of a biographer and novelist of the feminist generation, and Richard Holmes has presented Shelley as bound hand and foot by his depressive wife. But Seymour's work isn't biased enough to make it exciting. She doggedly follows the arc of Mary Shelley's life downwards, which means she is in anti-climax before the half-way stage and the writing is dull and infelicitous. Other writers will burgle the bank of this book and emerge with stories which may tell us less about the Shelleys, but more about the people who really interest us: ourselves.
Victoria White is the Arts Editor of The Irish Times