Paolo turned aft and called to Kenton: "Spring made up and ready for veering, sir!"

Kenton, who had been watching the Brutus as well as inspecting Monte Filippo with his telescope, said: "Very well, leave a couple of men there to veer the cable and bring the rest of your party aft to handle the spring."

Kenton had to admit that he had not liked the idea of leaving Orsini to check the mast angle and distance off when they anchored: his complete inability to understand mathematics was a joke in the Calypso, although fortunately he could handle a quadrant well enough, and even Southwick had to admit that he had never found the lad make a mistake in the actual sight.

The youngster had been cool enough; he had stood there watching the centre frigate through his quadrant eyepiece as though admiring the view, and when asked he had given quick and accurate estimates of the remaining distance. Kenton knew the Captain would be pleased to hear about that.

Now the Fructidor was anchored in precisely the right place, and the spring was on the cable. He suddenly had a slightly absurd picture of what they were doing to the ship. Or, since this was the first time, trying to do. The anchor and cable over the bow was as if a bull was tied to a tree (the anchor) by a rope through the ring in its nose. Then a thinner line was tied to its tail and taken to the rope and secured well in front of the bull's nose. By heaving on the line to the tail (the spring that went to the Fructidor's stern) the bull could be turned round to make it face a different direction.

Fortunately, the Fructidor was more tractable than a bull which, not unreasonably, would object to being pulled round by its tail. Now all that remained to do was veer away more anchor cable and spring so that the hitch holding the spring was further ahead, to give more leverage. Then, by heaving in on the cable Fructidor's stern would come round.

The men would haul and veer, haul and veer the spring until he had the ship lying at the angle which meant that the two mortars were aimed at the frigates. The spring, in more precise language, would make sure they were traversed correctly (the only time the words "left" and "right" were used in a ship). They were already elevated, and the gunpowder charge calculated for a range of 2,000 yards.

He pulled out his watch. Time was skidding past; they had twenty-five minutes left. Suddenly he remembered the Calypso and looked back towards Punta Avoltore. There she was, stretching up towards them under topsails, hull glistening black, gun ports closed, although he knew the guns would be loaded and the crews staying hidden below the bulwarks, ready for action. From ahead there was no mistaking that the Calypso was of the same class as the three frigates anchored over there in Porto Ercole. It gave him a strange feeling to think that he had been serving in her for the past year or more, and here she was bowling along on a wind with the Tricolour streaming out, to a stranger so obviously a French ship of war; belonging to a country with whom Britain had been at war for as long as he could remember.

They had reached what Mr Ramage had dubbed the "Gambler's Half Hour": he reckoned that the French frigates would not be in the slightest bit surprised at the two bombs coming in and anchoring a couple of thousand yards or so off the harbour entrance: they were expecting to see the bombs, and two thousand yards out was an obvious place to anchor. That part of the operation would be of no interest to the French officers in the frigates; indeed, apart from someone routinely reporting the fact to the senior officer, no interest would be shown: the senior officer would wait for the senior of the two bomb ketch lieutenants to have himself rowed in to report and receive fresh orders.

The gamble would come, Mr Ramage reckoned, from the time the spring was put on the cable and the bombs were slewed round, so that they were not lying head to wind to their anchors. At a casual glance someone on board the frigates might think that the two bombs were lying to a different slant of wind; that the high hills round the harbour deflected the wind outside. But if someone in the frigates was curious and put a glass on them, he might well spot the spring, even though it came on board on the side away from the harbour, because it had to be hitched to the anchor cable well ahead of the ship, otherwise there was not enough leverage to turn the ship round. But each bomb was showing a Tricolour, so there was nothing to show they were not French. And who knew much about bomb ketches anyway? Mr Ramage had made the point that the frigates might well think that bombs often anchored with a spring on the cable ...

So from the time the two bomb ketches started hauling round until the operation really began, precisely at half past eleven, there was a chance that the French might... Mr Ramage had shrugged his shoulders at that point: if the French realized their danger, they might cut the lines holding their sterns to the quay and rely on the weight of their anchor cables to pull them out so they could swing round enough to fire off a few broadsides, even if they ended up drifting on to the rocks on the south side of the harbour. Or one of them might cut everything and try to sail out of the harbour. Or the alarm might be given to Monte Filippo, Santa Catarina and La Rocca - no one knew if those guns could be used.

Kenton crouched down, sighting along the complicated mechanism with its spirit level which formed the mortar's sight. "Heave in - handsomely now!"

Eight men began heaving at the spring as it came through the aftermost gunport on the starboard side; a gunport which had long ago been lined along the two sides and bottom with thick copper sheeting, to take up the chafing of a rope being used in just this way, a spring to aim the ship and the mortars.

It took several minutes of heaving before the ship began to turn: there was slack in the anchor cable and slack in the spring. Finally, Paolo, watching the ship's head against the Feniglia, and Kenton, looking through the sight, saw the first movement. It was slight, and would remain so until the seamen could get a steady pull on the spring, but Kenton knew that once he let the ship swing past the exact bearing so that he had to order the men to veer, not haul, they might get flustered and the ship's bow would start swinging like the pendulum of a clock.

He told them to stop and belay and waited a couple of minutes, using the time to check that the Calypso was still approaching fast, coming clear of Isolotto and bearing away to head for the beach at the Feniglia, where she would turn and . . . Yes, another ten degrees would do it. He ordered the men to haul in ten feet of cable. The difference was so slight he could hardly measure it. Another ten feet ... ten ... ten ... ah, better. Ten more feet. Now he had the few houses in Grotte, the village at the northern end of the harbour, showing clearly. Another ten . . . ten more . . . just a fathom now, and there was the first frigate. He had to line up on the middle one - although the three of them looked like one enormously beamy ship. Another fathom . . . and one more . . .

"Belay that without losing an inch," he growled and remained crouching, watching through the sight, until Orsini reported: "It's belayed, sir."

Kenton snatched up his quadrant, checked the angle made by the mainmasthead of the centre frigate, found that veering the extra cable had made no perceptible difference, and stood up. The muscles of his thighs hurt so much that he realized he had been crouching for longer than he thought. Damn, the Calypso was closing fast!

He gave a string of orders and by the time the Calypso hissed past a hundred yards away, the shells were ready: a carefully measured charge had been poured into each mortar, a wad had followed, and then the shell had been lowered on top, its fuse cut to exactly the right length.