“Again,” said Leonardo.
“I’ll faint.”
“Then faint.
I’ll catch you.
I’ve caught heavier things.” He was standing on a stool by the scaffold with a lead plumb weight on a cord in one hand and a stick of chalk in the other.
“Ready?
When I let go, you do your trick, and you watch the weight, and you tell me where it was when the world came back.
Not where you think.
Where it was.”
It was the ninth day.
John’s arm had scabbed under the linen.
He’d slept every night on a pallet in the corner of the Sala del Papa behind a screen of drawings, and eaten Salai’s bread and Leonardo’s soup, and told the old man everything he could think of in exchange: wireless, motor cars, the shape of the earth, aeroplanes.
Leonardo had listened to the aeroplanes with his eyes shut and then gone very quiet and drawn a bird’s wing for an hour.
They’d started measuring on the second day, with candles and pulses, and on the seventh day Leonardo had his water clock.
“Now,” said Leonardo, and let go.
The weight swung away from his hand.
John pushed.
The hall went thick and slow.
The weight hung at the bottom of its swing, a dull grey drop at the end of a taut line, moving the way the hour hand moved: not at all, and then somewhere else.
Leonardo’s hand was still open where it had let go.
A fly had stopped in the air by the window with its wings blurred.
One.
Two.
Three.
Four.
Cold in his fingertips.
Warm on his lip.
It snapped back.
The weight swept on up its arc.
“There,” said John, pointing at the board behind the cord, where Leonardo had chalked a fan of lines.
“Third mark from the bottom.
Left of centre.”
Leonardo chalked it.
Then he looked at the water clock on the trestle, a copper bowl with a hole in the bottom dripping into a cup, and counted the drops in the cup with the tip of a brush.
“One drop,” he said.
“Not even.
In your head, four counts.
On the drip, less than one.
And on the weight…” He measured with his fingers on the board.
“A twentieth of its swing.” He climbed down, very pleased.
“You are a small, slow god, Giovanni.
For as long as it takes to say Ave.”
“Thank you.”
“I mean it kindly.
It’s a beginning.
You don’t walk the day you’re born.” He took John’s hands and turned them over.
The fingertips were white again, and the nails had gone a faint blue.
“Cold.
Each time colder.
And the nose.” He handed him a rag.
“And you eat like a horse after.
So it costs heat and blood and food.
Like a fire.
A fire in you, and it burns faster when you do it.” He tapped his own head.
“Mm.
What burns, can burn out.”
“I know.”
“Do you?
I wonder.” He wrote in his little red notebook, right to left, in the backwards hand John had seen in facsimile at the British Museum and never expected to see wet.
“Again tomorrow.
Today you’ll do the other thing.
The clay.”
* * *
The other thing had happened by accident, two days earlier, with the water clock.
John had built it the way Leonardo wanted: a shallow copper bowl from the convent kitchen, hammered smooth, with a hole in the bottom that he drilled with a bow drill and the finest steel point Zoroastro owned.
The hole was meant to be the size of a millet seed.
The water ran out in a thin, eager stream instead of a slow drip.
It was useless.
“Again,” said Leonardo.
“Another bowl.”
“There isn’t another bowl.
The cook says if we take another one she’ll poison us.”
So John sat by the brazier with the ruined bowl in his lap and his thumb over the hole, angry with himself in a way he had not been since his first week at the Fenwick, when he had wound a coil backwards.
He wanted the copper the way it had been an hour ago.
He wanted it badly enough that, without meaning to, he pushed.
He did not push at the room.
He pushed into the copper under his thumb.
The metal went warm.
Then it went cold, all at once, drawing the heat out of his thumb like a mouth.
Under his skin he felt the edges of the hole move.
It was very small and very slow, like a scab closing over a cut in a day instead of a week.
When he took his thumb away, the hole was the size of a millet seed.
The copper around it was bright and new, as if it had just come from the hammer, in a little ring no bigger than a coin.
The rest of the bowl was still old and dull.
His whole hand was white to the wrist.
Leonardo, who had been on the scaffold, had seen nothing.
John showed him.
The old man held the bowl up to the light from the window and looked at the bright ring for a long time without speaking.
Then he filled the bowl with water and watched it drip, one drop, then another, slow and even, a perfect water clock.
“You took it backwards,” he said.
“To before the drill slipped.”
“I think so.”
“And forwards?
Can you take a thing forwards?”
“I don’t know.”
“Then that’s tomorrow’s question,” said Leonardo.
He went straight to the clay bin, and by supper there was a horse on the trestle.
On the trestle by the window stood a horse the size of a cat, in grey clay, rearing, its mouth open.
Leonardo had made it two days ago as a study for the battle, and made it badly on purpose, he said, so he could watch John fix it.
John put his hands on it and pushed a different way.
Not to slow the room.
Into the horse.
The clay changed under his palms.
He felt it go, wet to dry, the way clay went in a week by a window, all in a breath.
The colour paled.
A crack opened along the neck, fine as a hair, then wider.
He pushed further, and the crack crept down the leg, and grains of clay began to crumble from the hoof onto the trestle.
He pushed back the other way.
That was harder.
That was like pushing a cart uphill.
The crack closed.
The colour darkened.
The clay went cool and damp again under his fingers, and the crumbs on the trestle stayed crumbs, because they weren’t part of it any more, and the horse stood there exactly as Leonardo had made it, badly, with its mouth open, a little shorter in one hoof.
John took his hands away.
They were blue to the wrist, and he couldn’t feel them.
“Dio,” said Leonardo softly.
He came and took John’s hands and shoved them, without ceremony, into his own armpits, inside his tunic, and held them there.
“Like a shepherd with a lamb.
Don’t argue.
You’ll lose your fingers.” He looked at the horse over John’s shoulder.
“Backwards and forwards.
But only what’s still part of it.”
“Only what’s still part of it,” John agreed, through his teeth.
“And alive?”
“I don’t know.”
Leonardo let go of his hands.
He went to the window ledge, where Salai’s dead hare from the market still hung on a nail by its back legs, two days older, and brought it to the trestle and laid it there with great gentleness, and looked at John.
John put one thawed hand on its fur.
He pushed, and the hare lay under his hand and stayed exactly as dead as it had been.
It was like pushing at the wall in the basement, but soft.
As if the hare simply wasn’t something time would let him into.
“No,” he said.
Leonardo nodded slowly, as if he’d expected it and was a little sorry.
“Good,” he said.
“Then you won’t be tempted.” He hung the hare back on its nail.
“Tempted men are dull.”
* * *
On the way to supper, John stopped at the door of the hall and put his hand on the top hinge.
It had squealed every time anyone came in for as long as he had been there.
Salai said it had squealed since the old Pope’s time.
The iron was black with rust, scaled like a fish, and the pin was rusted into the strap so hard it barely turned.
He did not tell anyone.
He pushed backwards into it, gently, as he had with the bowl, and felt the cold come into his palm.
It was easier than the clay, and harder than the copper.
Iron was stubborn.
It wanted to stay as it was.
He held it for about the time it takes to say an Ave slowly, and felt the scale loosen under his skin and the pin come free in its socket.
Then he stopped, because his fingers had gone white to the knuckle and Leonardo had said rest.
He opened the door.
It swung without a sound.
Zoroastro, coming up the stair behind him with an armful of firewood, stopped dead and looked at the hinge.
He opened the door and shut it twice.
He put down the firewood and looked at the hinge again, very closely, and at John’s white fingers, and then at John’s face.
“Lard,” said John.
“From the kitchen.”
Zoroastro sniffed the hinge.
It smelled of iron and nothing else.
He picked up his firewood and went past John into the hall without a word, and for the rest of the evening John caught him looking at the door.
* * *
That night John ate four bowls of Salai’s soup, and Salai, who had stopped putting less in his bowl since the morning with the lapis, watched him do it and said nothing.
Afterwards, by the brazier, Leonardo read back what he had written in the red notebook that day.
He read it in the order he had written it, from right to left on the page, translating his own mirror hand into speech without stopping.
“The holding.
Four counts when rested.
Three when tired.
Costs heat from the hands, blood from the nose, and food.
The body does not speed up with the mind.” He turned a page.
“The turning.
Works on clay and on copper.
Forwards ages the thing.
Backwards restores it, but only what is still part of it.
Costs more heat than the holding, much more going backwards.
Does not work on the dead hare.” He looked up.
“Does it work on you?
On your arm?”
John looked down at the bandage.
Under the linen, the cut had scabbed, an ugly ridge from wrist to elbow.
“I tried last night,” he said.
“When you were asleep.
It’s like the hare.
Nothing.”
“So you can mend a bowl and not a man.” Leonardo wrote it.
“That’s a mercy, Giovanni, though you won’t think so when you’re old.” He closed the notebook.
“Tomorrow, rest.
The day after, a lady comes to sit for her portrait, and I want you rested and clean and with your Florentine at least as good as a goatherd’s.”
“Who is she?”
“The wife of a silk merchant.
Her name is Lisa.” Leonardo stood up and stretched until his back cracked.
“And Giovanni.
Whatever you do with the world when you push it, you won’t do it to her.
She’s my sitter.
I’ve been trying to see her face for six months.
I don’t want it changed.”