The vast silence of that empty vista of fog-draped sea was pierced through with a battle's roar as a huge craft glided suddenly into view.

It was a Fomor warship, and it was engaged in a savage fight.

The powerful battleship of the Glass Tower fleet was a massive, sharply angled wedge of metal. Sleek-hulled and formed of polished black iron, it cut through the skein of wool-gray fog like a well-honed spear point. Its single mast showed no sail, yet the keen prow slashed its way steadily through the waves propelled by its silent, internal power.

Gray uniformed men at the sides and stern were working the massive crossbows mounted there. All were firing frantically now, spewing out an arcing fusillade of metal bolts toward a target at the rear. And that fire was being interlaced by a returning fire of slingshot pellets and hurled spears, creating a deadly rain on the laboring Fomor sailors.

The source of this withering fire hove from the fog into view close astern. This dreadnought that had once been a wolf of the seas was now being hotly pursued itself.

The pursuers were a fleet of a half dozen craft. Each one was a quarter the metal ship's size, of primitive design in wood, and propelled by sails or oars. Still, though looking inadequate against the hard-edged bulk of the Fomor ship, they made a fair opponent for the man-of-war. In fact, as the contending ships sailed on, locked in furious battle, it became quickly obvious that the Tower vessel was actually overmatched.

The intersecting exchanges of fire that wove a sparkling latticework through the grayness contained many more hits upon the Fomor than on its foes. And the pursuers were slowly but relentlessly closing in

The increasing frequency of the hits was soon inflicting continuous damage to the crews on the warship's sides and rear. Spears and stones were destroying men and damaging weapons. The accumulated effect was crippling the big ship.

Then a massive bolt was hurled by a huge figure in the bow of the closest small ship. This heavy missile looked vast for one human to wield, but it was cast with ease. It slammed home against the warship's flat stern, ramming in tight against the rudder.

The ship shuddered as the strike's impact shook the whole hull. On the Fomor main bridge, the command crew was sent reeling.

The Fomor captain, a lean and hawk-nosed man, grabbed the bridge rail barely in time to keep himself from falling. Face flushed as much by frustration as by rage, he turned to shout out at his crew:

"Where are our defenses? I want full fire from our stern!"

Another, younger officer stepped up to him.

"Captain, they are overreaching us," he said in a voice that could not hide his alarm. "Their fire is breaking through. We cannot win."

The captain turned to him in disbelief.

"You suggest we surrender, Commander?" he snarled out. "To that de Danann scum? You sound a coward, man. Back to your post! Keep all our fire at a maximum!"

The young officer, clearly stung by the rebuke, snapped a salute and wheeled away. Then he staggered as yet another, even more massive blow rocked the craft.

Outside, the entire stern of the warship was engulfed in a spectacular blossom of flaming debris, spreading outward from an explosion. It was caused by a second huge projectile hurled with such astounding force that it had pierced the black metal hull.

The attacker's fire had found a vital point at last.

On the Fomor bridge, a second junior officer listened to the damage report through a speaking tube from the ship's interior and looked to his captain in consternation.

"Captain, our portside screw has been disabled!" he reported. "We're losing headway!"

The young commander glanced back through the bridge's stern porthole to see the pursuing ships swiftly grow larger as they now rapidly closed in.

"They're almost on us, Sir!" he all but screamed at the captain in his fear. He could see figures swarming out onto the vessels' bulwarks and bows, swinging hooks on cables. "They're readying grapples!"

The captain's face drew into grim but determined lines as he rapped out the ominous order:

"Prepare to repel boarders!"

Through the stark corridors and across the deck the sharp sound of an alarm bell rang. From below more of the gray-clad crewmen swarmed to join their comrades already on deck. They formed a formidable array as the heavily-armed sailors rushed purposefully to their defensive positions.

While they formed up along the sides and stern, the attackers drew closer. They slid up on either side of the Fomor warship which was now little more than drifting ahead through the gray void. Soon the smaller craft were running parallel, like a dog pack on a fleeing stag, only a few yards away. The men filling their decks continued to launch withering barrages of fire, raking the Fomor ship.

The hunters matched speed with their prey. For moments they all seemed to hang suspended in the featureless fog, floating motionless together in an oddly peaceful-looking array. Then a shrill, warbling war cry was raised from one small ship. At its sound, the helmsmen of all the ships acted together. The craft began to slip sideways, closing the gap between.

The Fomor crew had by now all reached positions. Their companies had formed up at the most vulnerable points near the port stern, facing one of the largest of the attacking ships. Their weapons were up in a formidable barricade, the heavier armed men to the front. They meant to see none of their enemies reached that deck alive.

Not far away, the attacker's ships had now come within an easy throw. Several grapples on long lines were flung from each, arching outward and down to catch at any protuberance in the Fomor ship's side.

As the grapples made contact, Fomor crewmen scrambled to knock them free. Some succeeded, but many more sailors were knocked away from their goals by well placed shots of spear or pellet hurled from the enemy decks. The lines were being drawn in now, and the small ships pulling in tighter, tighter to the foe.