At high tide, the reef was completely covered by the sea, and only the narrow belt of white sand surrounding the island was left exposed. But a few hours later, the transformation was incredible. Though the range between high and low tide was only three feet, the reef was so flat that the water withdrew for miles. Indeed, in some directions the tide retreated so far that the sea disappeared from sight, and the coral plateau was uncovered all the way to the horizon.
This was the time to explore the reef; all the equipment needed was a stout pair of shoes, a broad-rimmed hat to give protection from the sun, and a face mask. The shoes were far and away the most important item, for the sharp, brittle coral could inflict scars that easily became infected, and then took weeks to heal.
The first time that Johnny went out onto the reef, Mick was his guide. Because he had no idea what to expect, everything was very strange-and a little frightening. He did well to be cautious until he knew his way around. There were things on the reef-small, innocent-looking things- that could easily kill him if he was careless.
The two boys walked straight out from the beach on the western side of the island, where the exposed reef was only half a mile wide. At first they crossed an uninteresting no man's land of dead, broken coral-shattered fragments cast up by the storms of centuries. The whole island was built of such fragments, which the ages had covered with a thin layer of earth, then with grass and weeds, and at last with trees.
They were soon beyond the zone of dead coral, and it seemed to Johnny that he was moving through a garden of strange, petrified plants. There were delicate twigs and branches of colored stone, and more massive shapes like giant mushrooms or fungi, so solid that it was safe to walk on them. Yet despite their appearance, these were not plants, but the creations of animal life. When Johnny bent down to examine them, he could see that their surfaces were pierced by thousands of tiny holes. Each was the cell of a single coral polyp-a little creature like a small sea anemone-and each cell had been built of lime secreted by the animal during its lifetime. When it died, the empty cell would remain, and the next generation would build upon it And so the reef would grow, year by year, century by century. Everything that Johnny saw-the miles upon miles of flat tableland, glistening beneath the sun-was the work of creatures smaller than his fingernail.
And this was only one patch of coral in the whole immensity of the Great Barrier Reef, which stretched for more than a thousand miles along the Australian coast. Now Johnny understood a remark that he had heard Professor Kazan make-that the Reef was the mightiest single work of living creatures on the face of the Earth.
It did not take Johnny long to discover that he was walking on other creatures besides corals. Suddenly, without the slightest warning, a jet of water shot into the air, only a few feet in front of him. "Whatever did that?" he gasped. Mick laughed at his amazement. "Clam," he answered briefly. "It heard you coming." Johnny caught the next one in time to watch it in action. The clam was about a foot across, embedded vertically in the coral so that only its open lips were showing. The body of the creature (partly out of its shell), looked like a beautifully colored piece of velvet, dyed the richest of emeralds and blues. When Mick stamped on the rock beside it, the clam instantly snapped shut in alarm-and the water it shot upward just missed Johnny's face.
"This is only a little feller," said Mick contemptuously. "You have to go deep to find the big ones-they grow up to four, five feet across. My grandfather says that when he was working on a pearling lugger out of Cooktown, he met a clam twelve feet across. But he's famous for his tall stories, so I don't believe it."
Johnny didn't believe in the five-foot clams either; but, as he found later, this time Mick was speaking the exact truth. It wasn't safe to dismiss any story about the reef and its creatures as pure imagination.
They had walked another hundred yards, accompanied by occasional squirts from annoyed clams, when they came to a small rock-pool. Because there was no wind to ruffle the surface, Johnny could see the fish darting through the depths as clearly as if they had been suspended in air.
They were all the colors of the rainbow, patterned in stripes and circles and spots as if some mad painter had run amok with his palette. Not even the most garish butterflies were more colorful and striking than the fish flitting in and out of the corals.
And the pool held many other inhabitants. When Mick pointed them out to him, Johnny saw two long feelers protruding from the entrance of a little cave; they were waving anxiously to and fro as if making a survey of the outside world.
"Painted Crayfish," said Mick. "Maybe we'll catch him on the way back. They're very good eating-barbecued with lots of butter."
In the next five minutes, he had shown Johnny a score of different creatures. There were several kinds of beautifully patterned shells; five-armed starfish crawling slowly along the bottom in search of prey; hermit crabs hiding in the shells that they had made their homes; and a thing like a giant slug, which squirted out a cloud of purple ink when Mick prodded it.
There was also an octopus, the first that Johnny had ever seen. It was a baby, a few inches across, and it was lurking shyly in the shadows, where only an expert like Mick could have spotted it When he scared it out into the open, it slithered over the corals with a graceful flowing motion, changing its color from dull gray to a delicate pink as it did so. Much to his surprise, Johnny decided that it was quite a pretty little creature, though he expected that he would change his views if he met a really large specimen.
He could have spent all day exploring this one small pool, but Mick was in a hurry to move along. So they continued their trek toward the distant line of the sea, zigzagging to avoid areas of coral too fragile to bear their weight.
Once, Mick stopped to collect a spotted shell the size and shape of a fir cone. "Look at this," he said, holding it up to Johnny.
A black, pointed hook, like a tiny sickle, was vainly stabbing at him from one end of the shell.
"Poisonous," said Mick. "If that gets you, you'll be very sick. You could even die."
He put the shell back on the rocks while Johnny looked at it thoughtfully. Such a beautiful, innocent-looking object-yet it contained death! He did not forget that lesson in a hurry.
But he also learned that the reef was perfectly safe to explore if you followed two common-sense rules. The first was to watch where you were stepping; the second was never to touch anything unless you knew that it was harmless.
At last they reached the edge of the reef and stood looking down into the gently heaving sea. The tide was still going out, and water was pouring off the exposed coral down hundreds of little valleys it had carved in the living rock. There were large, deep pools here, open to the sea, and in them swam fish much bigger than any Johnny had seen before.
"Come along," said Mick, adjusting his face mask. With scarcely a ripple, he slipped into the nearest pool, not even looking back to see if Johnny was following him.
Johnny hesitated for a moment, decided that he did not want to appear a coward, and lowered himself gingerly over the brittle coral. As soon as the water rose above his face mask, he forgot all his fears. The submarine world into which he had looked from above was even more beautiful, now that he was actually floating face down on the surface. He seemed like a fish himself, swimming in a giant aquarium, and able to see everything with crystal clarity through the window of his mask.
Very slowly, he followed Mick along the winding walls, between coral cliffs that grew farther and farther apart as they approached the sea. At first the water was only two or three feet deep; then, quite abruptly, the bottom fell away almost vertically, and before Johnny realized what had happened, he was in water twenty feet deep. He had swum off the great plateau of the reef, and was heading for the open sea.
For a moment he was really frightened. He stopped swimming and marked time in the water, looking back over his shoulder to check that safety was only a few yards behind him. Then he looked ahead once more-ahead and downward.
It was impossible to guess how far he could see into the depths-a hundred feet, at least. He was looking down a long, steep slope that led into a realm completely different from the brightly lit, colorful pools which he had just left. From a world sparkling with sunlight, he was staring into a blue, mysterious gloom. And far down in that gloom, huge shapes were moving back and forth in a stately dance.
"What are they?" he whispered to his companion.
"Groupers," said Mick. "Watch." Then, to Johnny's alarm, he slipped beneath the surface and arrowed down into the depths, as swiftly and gracefully as any fish.
He became smaller and smaller as he approached those moving shapes, and they seemed to grow in size by comparison. When he stopped, perhaps fifty feet down, he was floating just above them. He reached out, trying to touch one of the huge fish, but it gave a flick of its tail and eluded him.
Mick seemed in no hurry to return to the surface, but Johnny had taken at least a dozen breaths while he was watching the performance. At last, to the great relief of his audience, Mick began to swim slowly upward, waving good-by to the groupers as he did so.
"How big were those fish?" asked Johnny when Mick had popped out of the water and recovered his breath.
"Oh, only eighty, a hundred pounds. You should see the really big ones up north. My grandfather hooked an eight-hundred-pounder off Cairns."
"But you don't believe him." Johnny grinned.
"But I do," Mick said, grinning back. "That time he had a photograph to show it."
As they swam back to the edge of the reef, Johnny glanced down once more into the blue depths, with their coral boulders, their overhanging terraces, and the ponderous shapes swimming slowly among them. It was a world as alien as another planet, even though it was here on his own Earth. And it was a world that, because it was so utterly strange, filled him with curiosity and with fear.
There was only one way of dealing with both these emotions. Sooner or later, he would have to follow Mick down that blue, mysterious slope.
Chapter 9
"You're right, Professor," said Dr. Keith, "though I'm darned if I know how you could tell. There's no large school of dolphins within the range of our hydrophones."
"Then we'll go after them in the Flying Fish."
"But where shall we look? They may be anywhere inside ten thousand square miles."
"That's what the Survey Satellites are for," Professor Kazan answered. "Call Woomera Control and ask them to photograph an area of fifty miles radius around the island. Get them to do it as soon after dawn as possible. There must be a satellite going overhead sometime tomorrow morning."
"But why after dawn?" asked Keith. "Oh, I see-the long shadows will make them easy to spot."
"Of course. It will be quite a job searching such a huge area, and if we take too long over it, they'll be somewhere else."
Johnny heard about the project soon after breakfast, when he was called in to help with the reconnaissance. It seemed that Professor Kazan had bitten off a little more than he could chew, for the island's picture-receiver had delivered twenty-five separate photographs, each covering an area of twenty miles on a side, and each showing an enormous amount of detail. They had been taken about an hour after dawn from a low-altitude meteorological satellite five hundred miles up, and since there were no clouds to obscure the view, they were of excellent quality. The powerful telescopic cameras had brought the Earth to within only five miles.
Johnny had been given the least important, but most interesting, photo in the mosaic to examine. This was the central one, showing the island itself. It was fascinating to go over it with a magnifying glass and to see the buildings and paths and boats leap up to meet the eye. Even individual people could be detected as small black spots.
For the first time, Johnny realized the full enormous extent of the reef around Dolphin Island. It stretched for miles away to the east, so that the island itself appeared merely like the point in a punctuation mark. Although the tide was in, every detail of the reef could be seen through the shallow water that covered it. Johnny almost forgot the job he was supposed to be doing as he explored the pools and submarine valleys and the hundreds of little canyons that had been worn by water draining off the reef shelf at low tide.
The searchers were in luck; the school was spotted sixty miles to the southeast of the island, almost on the extreme edge of the photo-mosaic. It was quite unmistakable: there were scores of dark bodies shooting along the surface, some of them frozen by the camera as they leaped clear of the sea. And one could tell from the widening Vee's of their wakes that they were heading west.
Professor Kazan looked at the photograph with satisfaction. "They're getting closer," he said. "If they've kept to that course, we can meet them in an hour. Is the Flying Fish ready?"
"She's still refueling, but she can leave in thirty minutes."
The Professor glanced at his watch; he seemed as excited as a small boy who had been promised a treat.
"Good," he said briskly. "Everyone at the jetty in twenty minutes."
Johnny was there in five. It was the first time he had ever been aboard a boat (the Santa Anna, of course, hardly counted, for he had seen so little), and he was determined not to miss anything. He had already been ordered down from the cruiser's crow's-nest, thirty feet above the deck, when the Professor came aboard-smoking a huge cigar, wearing an eye-searing Hawaiian shirt, and carrying camera, binoculars, and brief case. "Let's go!" he said. The Flying Fish went.
She stopped again at the edge of the reef, when she had emerged from the channel cut through the coral.
"What're we waiting for?" Johnny asked Mick as they leaned over the handrails and looked at the receding island.
"I'm not sure," Mick answered, "but I can guess-ah, here they come! The Professor probably called them through the underwater speakers, though they usually turn up anyway."
Two dolphins were approaching the Flying Fish, jumping high in the air as if to draw attention to themselves. They came right up to the boat-and, to Johnny's surprise, were promptly taken aboard. This was done by a crane which lowered a canvas sling into the water, as each of the dolphins swam into it in turn, it was raised on deck and dropped into a small tank of water at the stern. There was barely room for the two animals in this little aquarium, but they seemed perfectly at ease. Clearly, they had done this many times before.
"Einar and Peggy," said Mick. "Two of the brightest dolphins we ever had. The Professor let them loose several years ago, but they never go very far away."
"How can you tell one from the other?" asked Johnny. "They all look the same to me."
Mick scratched his fuzzy head.
"Now you ask me, I'm not sure I can say. But Einar's easy-see that scar on his left flipper? And his girl friend is usually Peggy, so there you are. Well, I think it's Peggy," he added doubtfully.
The Flying Fish had picked up speed, and was now moving away from the island at about ten knots. Her skipper (one of Mick's numerous uncles) was waiting until they were clear of all underwater obstacles before giving her full throttle.
The reef was two miles astern when he let down the big skis and opened up the hydrojets. With a surge of power, the Flying Fish lurched forward, then slowly gained speed and rose out of the water. In a few hundred yards, the whole body of the boat was clear of the sea, and her drag had been reduced to a fraction of its normal amount. She could skate above the waves at fifty knots, with the same power that she needed to plow through them at ten.
It was exhilarating to stand on the open foredeck- keeping a firm grip of the rigging-and to face the gale that the boat made as she skimmed the ocean. But after a while, somewhat windswept and breathless, Johnny retreated to the sheltered space behind the bridge and watched Dolphin Island sink behind the horizon. Soon it was only a green-covered raft of white sand floating on the sea; then it was a narrow bar on the skyline; then it was gone.
They passed several similar, but smaller, islands in the next ho
ur; they were all, according to Mick, quite uninhabited. From a distance they looked so delightful that Johnny wondered why they had been left empty in this crowded world. He had not been on Dolphin Island long enough to realize all the problems of power, water, and supplies that were involved if one wished to establish a home on the Great Barrier Reef.
There was no land in sight when the Flying Fish suddenly slowed down, plopped back into the water, and came to a dead halt.
"Quiet, please, everybody," shouted the skipper. "Prof wants to do some listening!"
He did not listen for long. After about five minutes, he emerged from the cabin, looking rather pleased with himself.
"We're on the right track," he announced. "They're within five miles of us, chattering at the tops of their voices."
The Flying Fish set off again, a few points to the west of her original course. And in ten minutes she was surrounded by dolphins.
Arthur C Clarke - Dolphin Island Page 5
