Allday shouted, “The guardboat’s followed them in, Captain!” He gestured with his cutlass through a deep embrasure. “Mr Lucey’s lads are closing with them!”

Some of Lucey’s men were already running up the steps, while others were still locked in close combat with the guardboat’s crew across the jetty and out of sight below the wall.

Someone gave a hoarse cheer, and Bolitho saw another low shape edging through the breach, and heard Allday say fervently, “ ’Tis the gig, and not a blasted moment too soon!”

The additional weight of attackers was enough for the guard-boat, and caught between two prongs of the attack they started to throw down their arms, their voices almost drowned by the jubilant cheers from the seamen.

But that one delay caused by the guardboat’s unexpected appearance had cost Bolitho the precious minutes needed to reach the other stairway which led to the courtyard. Even as he waved his men forward he saw a serried line of musket flashes, heard the thud of a ball smashing into muscle and bone and screams on both sides of him.

The seamen hesitated, some pausing on the steps even though pushed forward by those from the boats behind them.

Bolitho rasped, “Come on, Allday! Now or never!”

Allday brandished his cutlass and bellowed, “Right, lads! Let’s open the door to the bloody bullocks!”

Once again they lunged forward. Beside Bolitho a man shrieked and toppled to the ground, his neck impaled by a musket ramrod. The soldier must have been so confused by the swiftness of the attack that he had failed to withdraw it after reloading.

All at once there seemed to be figures striking forward from every angle. The next instant they were locked steel on steel. As men reeled and kicked in the darkness, or fell on the blood of their comrades, Bolitho saw a Spanish officer hack down a screaming sailor and run towards him. Bolitho tugged a pistol from his belt and fired. In the bright flash he saw the top of the officer’s skull blasted away to spatter the wall behind him with bloody fragments.

Lucey ran past him, sobbing violently, his jaw clenched as he was carried forward by the wild mob of seamen.

Allday shouted, “There are the steps!” He swung his cutlass at a man kneeling by the wall. He could have been reloading his musket or using it as a crutch because of a wound. He dropped dead without even a whimper.

There was a lantern burning in the lower courtyard, and as they ran or fell down the steep steps Bolitho saw another force of soldiers already forming into line to resist them. Some of them were only partly dressed, others were covered with dust and chippings from the mortar’s bombardment, like workers in a flour mill.

An officer dropped his sword and a loud volley banged out from the wavering muskets. A few seamen fell dead or wounded, but the enemy’s aim had been bad, and they had no time for a further attempt.