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

It rolled into the community kitchen and tapped the steel counter where the plates go out. That counter is called the pass.

The pass had a dent in one corner, beaten flat again. In the dent, someone had scratched a tiny hammer.

Bà Tư was at the pass with her sleeves rolled up. On the counter sat one plum pie, still warm.

"Seven at the door, little ones," said Bà Tư. "One pie, seven plates. Nothing goes in the bin here."

Lan counted the faces at the door. Two neighbours, a bus driver, three children from the flats and an old man with a dog. Seven.

"Easy," said Beto. "I could cut that."

Beto found the plastic cutting guide in the drawer. It was a circle with lines like a clock. He laid it on the pie.

"Eight marks," he said. "Eight pieces. One spare. Someone can have two."

A woman in a cardigan was drying a bowl by the sink. She was a teacher at Brightfield, and on Saturdays she helped in the kitchen. Her name was Halver.

"Count the people, not the marks," said Halver. "Seven people. Seven pieces. Every piece the same size."

"But the guide has eight," said Beto.

"Then the guide is for a different day," said Halver. She smiled. "I used to be terrible at sharing. I'd have taken the spare."

"How do you cut seven?" asked Lan. "I'll do it! But how?"

Halver tore a long strip of baking paper. "Measure all the way round first."

She wrapped it round the pie tin and pinched where it met. Then she laid it flat by the ruler.

"Sixty-three centimetres," said Beto. "From where to where?"

"All the way round," said Halver. "That's the whole edge. Now share it between seven."

Beto worked it out. Seven nines are sixty-three. "Nine each!"

They made a pencil mark every nine centimetres along the strip. Then they wrapped it round the tin again. Seven marks, all round the edge, the same distance apart.

"You could use a protractor," said Halver. "A seventh of a turn is about fifty-one degrees. But a strip is easier."

A girl in a flour-dusted apron came in from the back with a tray of cups. Her family had run a pie shop for five generations. Her name was Pie.

"Name the piece before you serve it," said Pie. "What is one slice?"

"One of seven equal parts," said Beto.

"One of seven is a seventh," said Pie. "And seven sevenths make one pie. The tin tells you the whole."

Lan frowned. "But a seventh is smaller than an eighth. Seven is smaller than eight."

A tall grey heron stepped in through the back door, with a satchel of little flags. Her name was Liner. She walked to a chalk line on the kitchen floor that went from 0 to 1.

"Every fraction has its own spot," said Liner. She planted a flag for an eighth. Then one for a sixth. Then one for a seventh, just past the eighth.

"More pieces, smaller pieces," said Liner. "Cut a pie into eight, and each slice is smaller than if you cut it into seven."

Lan looked at the flags for a long time. "So a seventh is a bit bigger," she said. "Nobody gets cheated."

"Hands washed, then the knife with me," said Bà Tư.

Lan held the knife. Bà Tư put her hand over Lan's. Together they cut from each mark to the very middle. Seven cuts.

Seven slices. Seven plates. Seven sevenths.

The old man's dog looked hopefully at the tin. It was empty. Not a crumb went in the bin.

Bà Tư wrote the recipe on a card and gave it to Lan. It was the first of four recipe cards for the feast.

Back on the Green

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

At Lan's birthday there were five children and one round cake. Lan's mum reached for the knife.

"Wait," said Lan. "Count the people, not the marks."