The boy took the letter and turned it over in his hands. ‘Is it west or east of here?’

‘East. Towards the setting sun. If you follow the coastal path, you will get there some time tomorrow. And yes, you must leave now. No going down to the town to say goodbye to your mother.’

‘But . . .’

Solomon got up and stood in front of the boy. He was huge compared to him, far taller than any adult had a right to be. He held the boy’s shoulders and shook him firmly. ‘Are you not yet a man? How many summers have you seen?’

‘Thirteen in all.’

‘Then in my country you would be a man, with a man’s privileges and a man’s responsibilities. Why do they keep you as a child? Should I look for you playing with the babies, wiping their bottoms and rocking them to sleep? No? Then be a man, Brendan macFinn, a man your father can be proud of. Take what you need for the journey and be about your master’s business.’

Brendan took a blanket and slowly descended the stairs. Solomon went up to the roof and watched as the boy eventually left and started off over the hill, weighed down by his provisions. He stayed for a while to make sure that the boy didn’t double back, then went down to check on the still.

The smell from it was acrid, briefly burning the lining of his nose. It was a good, strong acid he was distilling, just right for his electropile. He walked around the room, checking by hand the things he had checked by sight earlier. He knew the boy had been meddling with something, or at least ought to have been. Curiosity was the best trait a natural philosopher’s apprentice could have.

He had a trunk. It used to contain the priest’s vestments, but he had emptied it out and moved it up into the tower. He opened it up and decided that the contents had been moved around. Brendan had been nosing inside, and Solomon thought it a most excellent moment. Even as the boy tramped the hills towards An Cobh, he would be thinking about the marvels he had seen. When he came back, he would beg Solomon to explain them to him. One at a time, and never enough, Solomon would.

He took out the heavy cloth-wrapped shapes and laid them out on the table: a set of three glass prisms that would not just bend light but shatter it into a rainbow. He dug deeper to find an oilcloth. He opened it out to reveal a brass machine that fitted into the palm of his hand, and another cloth that held a handful of steel discs, pierced in the centre and serrated around the circumference.

Further down was a big, solid object, wrapped in some animal skin that Solomon failed to recognize. This was his prize. He heaved it out and laid it on the table next to the prisms and the machine.

Reverently he unfolded the furry skin and ran his hand over the cold metal cover of a book.

CHAPTER 14

WHEN THEY CAME, Solomon was outside the graveyard, making a crude model of his water-lifting gear from sticks and seed pods. So absorbed was he in ensuring that his makeshift axle turned freely that he failed to hear the sound of hooves until the riders were picking their way down the steep hillside towards him.

He looked up, startled, and saw six horsemen in a single file. Each of them carried a round shield on his back and a spear tied off on his saddlecloth. The leader, a man with shaved cheeks and chin but a prodigious moustache, held Brendan macFinn in front of him.

Solomon rose to greet the High King’s men, and dusted his hands off against his legs. He assumed a formal pose and waited, a fixed smile on his face.

Then he realized that the moustached man had his hand over the boy’s mouth. He dithered for a moment, unsure of what to do next.

Brendan bit down on the man’s hand, and in the brief moment when he could, he shouted: ‘Master! These aren’t from the High—’

The man grabbed the boy’s shirt and heaved him off the horse. The other horsemen urged their mounts into a gallop. Brendan rolled to a stop and staggered to his feet. Solomon was still rooted to the spot.

‘Master, run!’

Finally Solomon moved. He vaulted the graveyard wall and sprinted for the tower, his heart hammering hard inside his chest. He shouldered the door open, then slammed it back shut, fumbling for the single bolt. He shot it home and stumbled backwards. He was safe for a moment.

There were footsteps, and the latch rattled.

‘Open up, Solomon Akisi.’

‘Who are you? What do you want?’

‘We want a word with you. The King of Coirc doesn’t like it when his friends try to stab him in the back.’

The King of Coirc? Solomon swallowed hard. The fool boy must have given the message to the wrong man.

‘I will not let you in,’ he stammered. ‘There has been a mistake, I am certain.’

‘Oh yes, for sure. A mistake in assuming that the good people of An Cobh couldn’t see off some pretender to the High King’s office. Now, herald of the Kenyan emperor, are you going to open this door and talk to us face to face?’

Solomon saw everything in a moment. How the boy had wandered through the remains of the battle at the gates of An Cobh, wondering where everybody was, when some vassal of the King of Coirc spotted him and asked him his business.

Of course, the letter had been taken straight to the king; warriors despatched to find out who in the land would offer his services to the defeated High King. How would they kill him in this country? Beheaded? Hanged? Drowned? Trampled? There were so many ways to die.

‘Right, boys,’ said the man, ‘get him out.’

There was a brief pause, a grunt, then the tip of an axe blade thudded into view.

Solomon turned and ran up the stairs to his room. He went straight to his trunk and felt for the brass machine. There was a key on a chain dangling from it, and he managed to slot it home at the third attempt, his fingers shaking.

‘Turn the key, turn the key,’ he muttered to himself, even as the sound of splintering wood echoed up the stairs.

He got the metal discs out, scattered them on the floor in front of him and picked one up. He pushed it home on the retaining pin and pressed the whole length of the device hard against the stone floor. Metal slid against metal, and he leaned harder. The spring inside squeezed tight and the locking mechanism clicked.

He raised his arm and sighted down it just as the top of a shield raised itself above the stairs.

‘If you move, I will kill you,’ he said.

The man laughed. ‘He sounds like he’s soiling his breeches. Come on.’ He moved further up the steps, and one of his companions edged upward behind him.

‘I warn you both. Get away from me.’ Solomon held the device with both hands to steady his wayward aim.

‘Look,’ said the first man, ‘he doesn’t even have a knife.’ He lowered his shield and swung his axe in a practised circle.

Solomon pulled the trigger and the steel disc whirled around, shot forward and buried itself in the man’s forehead, just above his brows. He stood for a moment, amazed and confused by what had just happened. The axe slipped from his fingers at the same time as the blood welled up out of the cut and down his face. He fell forward with an almighty crash.

Solomon concentrated on reloading: putting the key in and turning it, grabbing another disc, slotting it home, compressing the spring. As he looked up again, he stared at a spear point.

The remaining men stood around him, so close he could smell their sweat.

‘Drop whatever that thing is,’ snarled the moustached man. When Solomon didn’t instantly obey, he stepped forward and put his booted foot on the African’s wrist. ‘I’ll break both it and you if I have to.’

Solomon forced his fingers apart. The mechanism tripped and slammed the spinning disc against the floor. It ricocheted against the stone flags with a flash of sparks and buried itself in the chair. Such was the impact that the chair rocked backwards on its rear legs and, after an agonizing wait, fell over.