Petersen formed tapping crews for the same reason POW officers allocate duties to maintain morale. The men took turns using a wrench to rap SOS on the hull. As one man after another tired of the job, Petersen continued to tap away, although he wasn't sure why. Bored with the SOS, he began tapping out messages describing their plight. Eventually, he tired and rapped the bulkhead whenever strength allowed, which wasn't often. Then he stopped altogether. His thoughts turned from rescue, he shut his eyes, and once more he began to think of death.

Using the marker buoy line as his guide, Austin sank into the depths feet-first and slightly angled forward, like an old hard-hat diver being lowered at the end of an invisible air hose. Dancing rainbow shafts lanced the water like sunlight streaming through stain-glass windows. As Austin plunged deeper, the water filtered out the col- ors and the twilight abruptly turned into a violet night.

The powerful halogen lights mounted on the front of the Hard- suit caught snowy motes of marine vegetation and nervous schools offish in their beams, but before long, Austin was dropping into the benthic levels, where only the hardiest offish lived. At two hundred feet, his lights pick out the cruiser's masts and antennas, then the ship's ghostly contours materialized.

Austin hit the vertical thrusters and slowed to a stop at deck level. Then the horizontal thrusters whirred, and he cruised along the hull, rounded the stern and came back to the bow. The ship lay as shown in the sonar picture, at a slight angle on the slope, with the bow higher than the stern. He studied the ship with the intensity of a medical examiner inspecting the autopsied body of a murder victim, paying particular attention to the triangular gash in the side. No vessel could have survived the giant bayonet wound.

Seeing only twisted metal beyond the jagged opening, he moved toward the bow again. He approached within inches of the hull, feel- ing as dwarfed as a fly on a wall, leaned his helmet against the steel plating and listened. The only sounds were the hollow noise of his breathing and the whirr of thrusters as they kept the suit at a hover. Austin pushed off several feet, came around, goosed the horizontal thrusters and let his metal knees slam into the ship.

On the other side of the hull, Petersen's half-closed eyes blinked fully open. He held his breath.

“What was that?” a hoarse voice said in the darkness. Lars had been huddled on the bunk next to the captain's.

“Thank God you heard it, too/' Petersen whispered. ”I thought I was going mad. Listen."

They strained their ears and heard tapping on the outside of the hull. Morse code. Slow and measured, as if the sender were struggling with each letter. The captain's eyes widened like those of a cartoon character, as he translated the rough taps into letters.

P-E-T-E...