The nearest diver, Ken Knight, looked up at Pitt’s arrival. “I have your gear all ready for you, Major. I hope a single hose regulator will be OK, NUMA didn’t issue us any doubles this trip.”

“A single hose will do fine,” Pitt replied. He pulled on a pair of fins and strapped a knife to his right calf; then he slipped a mask over his head and adjusted the snorkel. The mask was the wide-angle type that gave the wearer a one hundred and eighty degree range of vision. Next came the air tank and the regulator. He was about to struggle with the tank harness when suddenly the forty pound outfit was swept from the deck and held at his back by two massive, hairy arms.

“How you could ever get through a day without my services,” said the voice of Giordino pompously, “is a mystery to me.”

“The real mystery is why l put up with your jackhammer mouth and overabundant ego,” Pitt said sourly.

“There you go, picking on me again,” Giordino tried to sound wounded but couldn’t quite pull it off. He turned and looked down at the passing water and, after a long pause, muttered very slowly; “Christ!

Look at the clarity of that water. It’s sharper than a goldfish bowl.”

“So I’ve noticed.” Pitt unsheathed the barbed tip of a six foot pole spear and checked the elasticity of the rubber sling attached to the butt end. “Have you studied your lesson?”

“The old gray matter,” Giordino said, pointing to his head, “has all the answers filed and indexed.”

“As usual, it’s comforting to know you’re so sure of yourself.”

“Sherlock Giordino knows all, sees all No secret can escape my probing mind.”

“Your probing mind better be well oiled,” Pitt said: earnestly. “You’ve got a tight schedule to keep.”

“Just leave it to me,” Giordino said straight faced. ‘Well, it’s about that time. I wish I was coming along.

Enjoy your swim and have fun.”

“I intend to,” Pitt murmured. “I intend to.”

Two chimes from the ship’s bell sounded Gunn’s one minute warning signal. Pitt, walking awkwardly in his fins, moved onto a small platform that extended over the side of the hull.

“At the sound of the next tone, gentlemen, we go!” He said no more, partly because each man knew what he had to do, partly because there was nothing else to say that had any meaning.

The divers gripped their spear guns a little tighter and silently exchanged glances. One thought and only one thought was on all their minds at this minute: if the jump isn’t far enough, a leg could be lost in the whirling propeller. At a gesture from Pitt, they arranged themselves in a line behind the platform.

Before he lowered the mask over his eyes, Pitt took another look at the men around him and for the tenth time studied their identifying features, features he would be able to recognize at a distance under water. The man nearest him, Ken Knight, the geophysicist, was the only blond in the group; Stan Thomas, the short, runty ship’s engineer, wore blue fins and was the only member, Pitt surmised, who could probably handle himself in a tough fight. Next came a red-bearded marine biologist, Lee Spencer, then Gustaf Hersong, a lanky six-foot-six marine botanist — both those men seemed to be grinning at each other over a private joke. The anchor man was the expedition’s photographer, Omar Woodson, as true a deadpan character as Pitt had ever seen and who genuinely appeared bored by the whole show.

Instead of a spear gun, Woodson carried a 35 mm Nykonos with flash, swinging the expensive underwater unit over the railing, negligently, as if it were an old used box camera.

Pitt pulled the mask down over his eyes, whistling softly to himself, and gazed once more at the water. It was passing beneath the platform at a much more leisurely rate now — Gunn had cut the First Attempt’s speed to a crawling three knots — slow enough, Pitt decided, for a feet first entry. His eyes turned past the bow, looking forward with trance-like fixity at the approximate point in the sea where at any moment now he must dive.

At almost the same instant, Gunn scrutinized the fathometer and the jagged cliffs for the last time. His.

hand slowly raised, groped for the bell line, found it, paused, then gave one hard pull. The metallic clang burst into the hot afternoon air and carried across the surf to the steep coastal wall, echoing in a muted undertone back toward the ship.

Pitt, poised on the platform, didn’t wait for the echo. Holding the mask firmly in place against his face with one hand and clutching the pole spear in the other, he leaped.

The impact shattered the sun-danced water into a blazing diffused pattern of blue brilliance. Immediately after the surface closed over his head, Pitt rolled frontward and kicked his fins as fast, it seemed to him, as a Mississippi River paddle wheeler at full throttle. Five seconds and fifteen feet later, he glanced over his shoulder and watched the dark shape of the ship’s hull slide slowly overhead. The whirling twin propellers seemed frighteningly closer than they really were: their thrashing sound traveled at forty-nine hundred feet per second underwater as compared to less than eleven hundred feet through air, and the light refraction magnified their flashing blades by nearly twenty-five percent.

Teeth clenched on the regulator’s mouthpiece, Pitt swung around and stared in the direction of the shrinking ship to see how the others had fared. His sigh of relief was answered by the hiss of his exhaust bubbles from the regulator. Thank God, they were all there, and in one piece. Knight, Thomas, Spencer, and Hersong, all in a group within touching distance. Only Woodson had dragged his feet; he hung in the water about twenty feet beyond the rest.

The visibility was startling. The long, purplish tentacles of a jelly-like Portuguese Man O’ War were clearly discernible nearly eighty feet away. A pair of ugly looking Dragonet fish swam idly across the bottom, their vivid blue and yellow scaleless bodies topped by high slender gill spines. It was a hidden world, a soundless world, owned by weirdly shaped creatures and decorated by graceful fantasies of form and vibrant hues that defied any attempt at human description. It was also a world of mystery and danger, guarded by a sinister array of weapons, varying from the slaughterous teeth of the shark to the deadly venom of the innocent looking Zebra fish; an intriguing combination of eternal beauty and constant peril.

Without waiting for signs of discomfort, Pitt began snorting into the mask to equalize the air pressure of his inner ears to that of the water pressure. When his ears popped, he slowly dove toward the majestic seascape under him and became a part of it.

At thirty feet, the reds were left behind, and the depths became a soft blending of blues and greens. Pitt leveled off at fifty and studied the bottom. No sea growth or rocks here, just a patch of submerged desert where miniature sand dunes meandered in unbroken snake-like ripples. Except for an occasional bottom-dwelling Star Gazer fish, buried with only a pair of stony eyes and a portion of its grotesque, fringed lips protruding above the sand, the sea floor was deserted.

Exactly eight minutes after they had left the First Attempt, the bottom began to slope upward, and the water became slightly murky from the surface wave action. A rock formation, covered with swaying seaweed, appeared in the gloom ahead. And then suddenly they were at the base of a vertically sheer cliff that rose at an unbroken 90 deg. angle until it disappeared into the mirrored surface above. Like Captain Nemo and his companions exploring an undersea garden, Pitt began directing his team of marine scientists to spread out and search for the submarine cave.

The hunt took no more than five minutes. Woodson, who had angled a hundred feet out on the right perimeter, found it first. Signaling Pitt and the others by rapping his knife against his airtank, he motioned for them to come and went swimming off along the northern face of the cliff to a point beyond a weed-encrusted crevasse. There he paused and held up a leveled arm.