'Forward!' Napoleon thrust his sword towards the gate. 'Forward!'

The grenadiers rushed up the path towards the narrow bridge over the defence ditch. Napoleon charged in with them. Behind him the remaining companies let out a deep-throated cheer and broke into a dead run towards the gate. A flicker of motion above drew Napoleon's eye and he saw the other sentry thrust his musket over the wall and swing the muzzle towards him until the barrel foreshortened into almost nothing.Then there was a stab of flame and smoke and something snatched the hat off Napoleon's head. He did not even have time to register that the musket ball had missed his skull by inches before he was rushing through the gates and into the fort beyond. Behind the gatehouse was a large open courtyard lined with barracks and stores built into the walls. A soldier, wearing just his breeches, was blowing on a bugle as more men tumbled from the doors of their quarters, half dressed, and clutching their muskets and cartridge pouches.

'Over there!' Alessi pointed towards them. 'Charge!'

Without waiting for his men, Alessi pointed his sword and sprinted across the courtyard. Some of the grenadiers rushed after him, while others, more cool-headed, paused, took aim and fired. Three shots found their targets in rapid succession and the Sardinian soldiers pitched forwards or were flung back by the impact. Then Alessi and his men were in amongst them, snarling and shouting like animals as they thrust their bayonets, or clubbed at men with the heavy wooden butts. Napoleon ignored them, and looked round for the commander of the garrison.

A door opened close to the gatehouse and a man emerged from within, clutching a gilt-handled sword. He gazed about in bewilderment for a moment before his eyes alighted on the shattered timbers of the gate, and Napoleon. His features hardened and he rushed from the doorway, sword point directed at the French officer's breast. Napoleon just had time to slash his blade across horizontally and parry the thrust. Metal scraped on metal and then the man cannoned into Napoleon, sending them both crashing to the ground.The air exploded from his lungs and Napoleon gasped for breath, winded, as the enemy officer rolled to his feet, raised his sword and stared down at Napoleon in triumph. Then came the tramp of iron-nailed boots as the following wave of volunteer troops poured through the gateway. The Sardinian officer just had time to look up before two bayonets ripped into his stomach and carried him back into the fort and he collapsed on the ground with a grunt. One of the volunteers ripped his crimson point free, reversed his musket and smashed the butt into the enemy officer's forehead, silencing him at once.

'You all right, Colonel?' One of the volunteers reached down and hauled Napoleon to his feet.

He tried to answer but was still short of breath and nodded instead. 'Get… forward,' he managed to gasp.

The volunteer nodded and charged on, disappearing inside one of the doors hanging open beneath the walls of the fort. Napoleon leaned forward, resting his hands on his knees and struggled to recover his breath as more of his men charged by and flooded the fort with blue uniforms. But the fight was already over. Those Sardinians who had managed to answer the call to arms were all dead or wounded, and the rest had surrendered or had gone to ground in their quarters. It took a moment for the men of the Ajaccio battalion to realise they had won, and that the fort was theirs. The fire that had burned in their veins subsided, and the grim expressions on their faces slowly melted into relief and then the brief euphoria of having fought and won. A cheer ripped from their throats and the men waved their hats and muskets in the air as the sun blinked over the far wall of the fort.

Napoleon indulged them for a moment before he strode across the courtyard to Alessi and beckoned to the other officers to join him. He gave orders for the prisoners to be held in their barracks, their wounded to be treated with the four Corsicans who had been injured in the assault, and then he sent a runner back to the beach to inform Colonel Colonna that the fort was in their hands and that the unloading of the eighteen-pounders could begin.

Two companies of men were sent back to help drag the long guns up to the fort and another company was set to work repairing the gate and strengthening the eastern wall of the fort with timbers torn out of the fort's storeroom to bear the weight of the eighteen-pounders. Then Napoleon climbed to the wall that overlooked the stretch of sea towards the island of Caprera. In between the two islands was a small rock on which a watchtower had been erected to maintain complete surveillance over the channel. Napoleon was sure that they had heard the cannon used to blow open the gates, and would soon be passing the information on to the main island of Sardinia.That could not be helped.

As the sun rose into a clear cold winter sky the air rang with the sound of saws and hammers and the chanted chorus of men heaving together on ropes as they worked on the ramparts. Just after midday a sentry on the gatehouse announced that Colonel Colonna was approaching. Napoleon met him outside the fort. He looked past the colonel along the track.

'How far back are the guns, sir?'

'Quarter of a mile. Maybe less. I'm sure they'll be here soon enough. Now, if you'd be so good as to show me over the fort?'

'Of course, sir.'

Napoleon escorted Colonna inside and he made a great show of praising the battalion before he insisted on seeing the prisoners. The men were herded out into the daylight and they looked at the new arrival apprehensively as Colonna sneered at them.

'Is this the best that Sardinia can muster to throw against us?' he asked loudly. 'I've seen more dangerous-looking goatherds in the hills around Bastia!' He paused to direct his next remark at the nearest group of volunteers. 'No wonder we gave them such a sound thrashing, eh, men?'

The volunteers gave him a good-natured cheer and Alessi nudged Napoleon and muttered. 'We? Can't say I noticed Colonna during the assault.'

'Shh!'

Colonna left the prisoners and continued his way round the fort, congratulating the men, and when he had finished he sent a soldier to find him some food and wine for lunch, which he proceeded to eat at a small table on the eastern wall as he gazed across the channel towards Caprera. Napoleon turned to Alessi. 'See what can be found for the battalion to eat, if he's left anything.'

As Colonel Colonna finished his meal the first of the eighteen-pounders was dragged into the fort and hauled up the ramp on to the makeshift gun platform that had been strengthened with beams from one of the storerooms. When the naval gun carriage was in position the men used more beams to make a hoist and then forty men took up strain on the rope and hauled the barrel off the ground.When it had reached a sufficient height the gun carriage was rolled in underneath and then the barrel was lowered until the trunnions were in position and capped securely. Then the men released the rope and slumped down, breathless and sweating from their labours.When the second gun arrived the whole process had to be repeated, but by mid-afternoon Napoleon stood on the wall, hands on hips admiring their achievement.

'Right then! Time to announce our intentions!' Napoleon grinned and then gave the orders for the guns to be loaded and run up to the parapet. Once again he did not trust anyone else to lay the guns as he trained them on the watchtower in the channel. Then he stood back and handed command of the cannon back to the navy gun captains who had come ashore with their charges. Standing clear of the guns Napoleon raised his arm, paused, and then swept it down. 'Number one gun! Open fire!'

The roar of the eighteen-pounder, the gush of flame and billowing cloud of smoke took everyone but the navy gun crews by surprise after the much lighter crash of the six-pounder that had opened the attack. The first shot splashed into the sea a hundred yards short of the watchtower as a plume of white spray erupted from the swell. The second shot, from the other gun, appeared to hit the rock beneath the tower. Alterations to elevation were made and the third shot hit the crest of the tower, dislodging masonry that tumbled into the sea. Now that the range had been acquired the guns proceeded to pound the watchtower to pieces.