ytically.

Was _he_ basing action on analytic reason?

Another hour had passed. And then he heard it. The sound of faint sonar
communication. Quickly he nosed upward to twenty feet, throttled back to
half speed, and raised the periscope. With his face pressed against the
eyepiece, he scanned the moonlit ocean in a slow circle. No lights, no
silhouettes against the reflections on the waves.

He started the pumps and prepared to surface. Then the conning tower was
snorting through the water like a rolling porpoise. He shut off the
engines, leaving the sub in utter silence except for the soft wash of
the sea. He adjusted the sonar pickups, turned the amplifier to maximum,
and listened intently. Nothing. Had he imagined it?

He jabbed a button, and a motor purred, rolling out the retractable
radar antenna. Carefully he scanned the sky and sea, watching the
green-mottled screen for blips. Nothing--no ships or aircraft visible.
But he was certain: for a moment he had heard the twitter of undersea
communicators.

* * * * *

He sat waiting and listening. Perhaps they had heard his engines,
although his own equipment had caught none of their drive-noise.

The computer was able to supervise several tasks at once, and he set it
to continue sweeping the horizon with the radar, to listen for sonar
code and engine purr while he attended to other matters. He readied two
torpedoes and raised a rocket into position for launching. He opened the
hatch and climbed to stand in the conning tower again, peering grimly
around the horizon.

Minutes later, a buzzer sounded beneath him. The computer had something
now. He glanced at the parabolic radar antenna, rearing its head a dozen
feet above him. It had stopped its aimless scanning and was quivering
steadily on the southeast horizon. _Southeast?_

He lowered himself quickly into the ship and stared at the luminous
screen. Blips--three blips--barely visible. While he watched, a fourth
appeared.

He clamped on his headsets. There it _was_! The faint engine-noise of
ships. His trained senses told him they were subs. Subs out of the
southeast? He had expected interception from the west--first aircraft,
then light surface vessels.

There was but one possible answer: the enemy.

He dived for the radio and waited impatiently for the tubes to warm
again. He found himself shouting into the mic.

"Commsubron Killer, this is Sugar William Niner Zero. Urgent