The hammer rang once. A spark jumped off the anvil and did not go out. It waited. They followed.

It went past the coins and the old maps to a case that held a single small book, open at its title page. The paper was brown at the edges. The title was in capitals, and under it there was a short quotation from an old poem, and the year, 1818.

There was no author's name. Where the name should have been there was nothing at all.

The card beside the case said: Begun by an eighteen-year-old, as a ghost story, on a wet summer night.

This is a true story. Where nobody knows something, the story says so.

Mary Wollstonecraft Godwin was born in London on 30 August 1797. Her mother was Mary Wollstonecraft, a writer who had argued in a famous book that girls deserved the same education as boys. Her father was William Godwin, a philosopher whose books had made him, for a while, one of the most talked-about men in England.

Her mother died eleven days after Mary was born, of an infection caught in childbirth.

So Mary grew up with a famous mother she could not remember. She read her mother's books. Her father's house was full of writers and thinkers who came to dinner and argued, and Mary, a quiet child, sat in the corner and listened. She had almost no schooling. She had her father's library instead.

In 1814, when Mary was sixteen, a young poet called Percy Bysshe Shelley began to visit her father. He was twenty-one, wildly clever, rich by birth and already married. He and Mary fell in love. That summer, against her father's wishes, they ran away together to France, taking Mary's stepsister Claire with them.

It was a scandal. Her father would not speak to her for a long time. In 1815 Mary gave birth to a baby girl, too early. The baby lived less than two weeks. Afterwards Mary wrote in her journal that she had dreamed the baby came back to life, that they warmed her by the fire and she lived.

She was seventeen.

In April 1815, on the other side of the world, a volcano called Tambora, on an island in what is now Indonesia, erupted. It was one of the largest eruptions in recorded history. It threw so much ash and gas into the high atmosphere that for more than a year less sunlight reached the ground across much of the northern half of the world.

In Europe, 1816 became known as the year without a summer. Crops failed. It snowed in June in some places. It rained and rained.

That summer, Mary and Percy, with their baby son and with Claire, travelled to Switzerland, to the shore of Lake Geneva. Across a field from their house was a large villa, the Villa Diodati, rented by the most famous poet in Europe, Lord Byron. Byron had brought a young doctor with him, John Polidori.

The weather kept them all indoors. There were thunderstorms over the lake that lit up the mountains at night. They talked late, about poetry, about science, about whether a dead body might be brought back to life with electricity, which some scientists of the day had experimented with on frogs. They read German ghost stories aloud, from a French translation.

And one evening, Byron made a suggestion. Each of them, he said, should write a ghost story.

Byron began one and soon gave it up. Percy started one and did not get far. Polidori later wrote a story called The Vampyre, which became famous in its own right.

Mary could not think of anything.

Fifteen years later, in 1831, Mary wrote down what those days were like. Every morning, she wrote, someone would ask her whether she had thought of a story, and every morning she had to say no. She described the feeling as the worst thing that can happen to a writer: blankness, an empty space where an idea should be.

Then, she wrote, one night she listened to Byron and Percy talking about electricity and life, about whether a body could be made to live. She went to bed and could not sleep. With her eyes closed, she said, she saw a picture as clear as anything she had ever seen awake.

Her own words, from 1831: "I saw the pale student of unhallowed arts kneeling beside the thing he had put together."

She saw the creature stir. She saw the young man who made it run from it in horror, and fall asleep, and wake to find the thing standing by his bed, looking at him.

She opened her eyes, frightened. And then, she wrote, she realised she had her ghost story. What had frightened her would frighten other people too.

The next day she began to write. The first words she put down, she said, were the ones that now begin the fifth chapter of the finished book: It was on a dreary night of November.

She was eighteen.

She meant to write a short tale. It grew. Percy encouraged her to make it longer, and over the next year, through more travel and more grief, she turned it into a novel.

She wrote in notebooks, in her own hand. Those notebooks survive, in a library in Oxford, and scholars have studied them line by line. Percy's handwriting is in them too. He suggested changes to words and sentences here and there, some of them improvements and some of them not. For a long time people argued about how much of the book was really his. The notebooks answer most of that argument. The story, the shape and nearly all the words are hers.

She was writing it while her life kept breaking around her. In the autumn of 1816 her half-sister Fanny died. In December, Percy's first wife died too. Mary and Percy married at the end of that year. Through all of it she kept going back to the notebooks.

It was about a young scientist, Victor Frankenstein, who builds a living creature from dead body parts and brings it to life. Then, appalled by what he has made, he abandons it. The creature, who has done nothing wrong, is left alone in a world that runs from him. He teaches himself to speak and to read, by hiding in a shed beside a cottage and listening to the family inside, and by studying the books he finds. He reads about history and about love. He reads the notes Victor kept while making him, and learns, from his maker's own handwriting, how disgusted his maker was. He asks, again and again, why the man who made him will not take responsibility for him. And when no one will love him, he becomes the monster everyone already believed he was.

The novel was published on 1 January 1818, in three small volumes. Only five hundred copies were printed. It carried no author's name. Many reviewers assumed that Percy Shelley had written it. A second edition in 1823 put Mary's name on it.

She was twenty when the first edition came out.

Mary Shelley went on writing for the rest of her life: novels, stories, travel books, and the first careful editions of her husband's poems after he drowned in 1822. She died in 1851.

Frankenstein has never been out of print. Within five years of its publication it had been turned into a play in London, and Mary went to see it. In a letter afterwards she said she was much amused, and that the creature, who in the play could not speak, was well acted. On the playbill the creature's name was left as a blank line. Since then the story has been made into hundreds more plays and films. The word has entered the language. Many people now think Frankenstein is the name of the monster. It is the name of the man who made him and then ran away.

Some readers call it the first science-fiction novel. Others say it is a book about what we owe to the things we make.

Tara stood by the case for a long time.

She thought about a seventeen-year-old dreaming that her baby came back to life. She thought about a rainy summer caused by a volcano she had never heard of, on the other side of the world. She thought about the story Mary told fifteen years later, which is beautiful and might be partly tidied up, the way everyone tidies a story they have told many times. And she thought about the title page, with its blank space, in the book everyone knows. Two blanks, really: no name for the author on the book, and no name for the creature on the playbill. Both of them had made something, or been made, and been left unnamed by the people who should have known better.

The spark sat on the edge of the glass, very small.

If you had made something new, and it went out into the world with someone else's name guessed on it, would you rather be known for it, or would you rather it was read?

The spark dimmed to a warm dot and settled back on the anvil. The Green was just the Green again.

Back on the Green

At the Whetstone, Tara wrote in her notebook and dated the line.

It is the name of the man who made him and then ran away.

Danya read it. "Who checked the dream?" he said.

"Nobody can," said Tara. "Only she was there. She wrote it down fifteen years later."

Which line from this story would you keep?