wo ought to be drawn into our joint project. Or, at least, Anatole-" Rita remained silent. Finally she said: "I think he'll realize that himself. Anyway, I can't stay here any longer. You promised to think of a way out. Well, keep your promise." Nikolai was on the point of saying that he couldn't conjure up a south wind, but he refrained. Towards the end of the eleventh day, after supper, when it had grown somewhat cooler, Val suddenly burst into laughter. "What a sight you are!" she said, running her eyes over the three young men. "You're unshaven and dirty-faced. You look like savages." She put her hand out to touch Yura's soft reddish beard. He jerked his head away and clicked his teeth. She drew back her hand. "You really have turned into a savage," she said. "You know, Val, you and I don't look any better," Rita remarked, her glance falling on her scratched and bruised arms and her broken fingernails. "You're right," Val agreed mournfully. "How grand it would be to wash my hair in fresh, hot-water and to put on a little perfume-" "You know what? Let's drive the men away tomorrow and heat up some water. We'll have a glorious bath." "You're wonderful, Rita!" Val cried. "And let's do the laundry too." This conversation took place on the eve of their twelfth day on Ipaty Island, a day of important events. Next morning Nikolai, Yura and Valery brought armfuls of seaweed to the campfire and burned it for ashes. They carried fresh water from the pools near the mud volcanoes and filled all the vessels. Then they departed. Rita and Val scrubbed the clothes, using ashes and volcanic clay for soap, and had a good wash themselves. Meanwhile, the three young men went swimming off the southern tip of the island, diving and fishing with their spear gun. Afterwards they stretched out to rest on the beach of the cove. Rex went up the slope in pursuit of a lizard. "I swam to the other side of that headland," said Nikolai. "The water there is agitated; there must be a strong discharge of gas at that particular spot." "Yes, we're living on top of a volcano," Yura stated. He was lying on his back, his face covered with his faded red kerchief. "How hot it is today! Feels like there's going to be a change in the weather." They lay motionless, exhausted by the heat and their long stay in the water. Suddenly they heard a faint sound in the dead silence of high noon. Nikolai sat up and cocked his head. "What's that? An engine?" The sound was repeated a moment later and then stopped short. Nikolai scooped up the binoculars and ran to the top of the slope. Yura and Valery followed close behind him. A boat was coming towards the island from the west. Although it was still far away they could make out three figures in it. One of them was steadily bending forward and then backward. "It sounded like a motorboat. Why should they be rowing?" "Let's have a look." Yura took the binoculars from Nikolai. "They're coming this way. And I'll be damned if that isn't Uncle Vova Bugrov at the oars!" Nikolai snatched the binoculars away from him. Yes, it was Bugrov. He sat with his back to the shore, but he turned to look at the island two or three times and Nikolai recognized him. Bugrov was propelling the motorboat towards the island with strong strokes of his oars. Now Nikolai could make out the two passengers. One of them was Opratin. He sat in the stern, in a short-sleeved green shirt and a straw hat. The third person, a thickset, shaggy man, sat hunched over in the bow. Nikolai could see only his back, across which a white shirt stretched tight, but he immediately knew the man was Anatole. "How do you like that?" Nikolai asked, handing the binoculars to Yura again. "They've certainly chosen a secluded spot for their experiments," said Yura. "Shall we let them know we're here?" Nikolai did not answer at once. "Should I tell Rita?" he wondered. From their hollow on the north-eastern shore the girls would not see a boat approaching from the west. Best not to hurry. He and Yura and Valery would watch a while longer. "Wait a bit," he said. "Let's see what they're up to." Yura nodded. "Right you are. There must be some important reason why they've hidden themselves away on this island. Let's go over to the big crater. The grass is high there and we'll have a good view." They whistled for Rex to come back to them and then stretched out on the slope of the crater. The sun blazed down on their backs; the stiff, prickly grass scratched their bare skin. But they had a perfect observation post. The cove lay spread out below them. The nose of the boat touched the shore. Bugrov sprang out into the deep water and tied the painter to a ring on the mooring post. Next, Opratin and Anatole stepped out of the boat. Anatole at once started up the slope, panting and halting at frequent intervals to catch his breath. Opratin remained behind to talk with Bugrov. "Good thing we were close to the island when the engine died on us," they heard Bugrov say in his booming voice. "I'll have to check the ignition." Opratin said something and then turned away to follow Anatole in the direction of the reinforced concrete dome. They vanished from view when they descended into the hollow in front of the pillbox door. The bolt clanked, then the massive door creaked and slammed shut. Bugrov got down to work on the beach. He took the ignition distributor out of the engine and laid it on a piece of canvas spread on the ground. Yura, Nikolai and Valery continued to lie in hiding for some time, watching him work. "I'm fed up with this cat-and-mouse stuff," Yura finally whispered. "We ought to come out into the open and let them know we're here." "Wait a bit," Nikolai insisted. "Then let's move into the shade. My brains are sizzling." Bending low, they noiselessly skirted the mud volcano and came into the shade near the concrete outlet of the ventilation shaft. The heat was less oppressive here. Cool air from the underground chamber was wafted to them through the dark grating covering the shaft. They could hear a faint rustling. Suddenly Anatole's voice came to them-so clearly that they gave a start and involuntarily bent lower. "You'll have to get along without me," Anatole was saying. "I'll do what I have to do." "Contact Bagbanly? Privalov?" Opratin's voice was so muffled they could barely make it out. They leaned closer to the grating, their bodies tense. "Yes, I will. I'll give them the material and we'll all work together." Opratin's voice was calm. "You have no right to do that without my consent." "Do you have the right to use the Institute laboratory, which isn't yours, and to buy expensive equipment for this project on the Institute's money?" There was a short pause. "So that's how you view the matter," said Opratin. "Very nice of you. Why have you considered it possible to work here up until now? Why this crisis of conscience all of a sudden?" Anatole muttered something and gave a cough. "The result is what counts," Opratin went on. "No one's going to blame us after we announce a major breakthrough. Winners are never blamed." "We haven't anything to announce. There isn't any breakthrough." "Yes there is. Penetrability is in our hands." "It's like a grenade in the hands of a child. No stability. We don't know the essence of the phenomenon." "In another month or two we'll achieve stability." "You're deceiving yourself!" Anatole shouted. Rex growled softly in reply and received a slap from Nikolai. Fortunately, the men below had not heard the dog. "We've reached an impasse," said Anatole. "We're not making any headway. We must climb out of this damned cellar and write to the Academy of Sciences. I realized that long ago, but I was just being obstinate-" "You have no right to do that," Opratin said in a harsh voice. "We did the work together." "Very well. I won't say anything about the circuit you developed. You can choke on it for all I care. But the idea of the 'transmission effect' is mine. I'm taking the knife and I'll write up a paper on my own work." Yura's eyes were round as he nudged Nikolai with his elbow. The knife! "You forget, my dear man, that I was the one who obtained the knife," Opratin remarked coldly. "She gave you the knife only because of me, and not because she was smitten with you. Ah, if only I had listened to her! Oh well- But why are you being so stubborn?" Anatole asked after a pause. "We've done an enormous amount of work. Let's declare honestly that we can't go any farther without help. Fame and honours won't slip through our fingers-" "That's enough!" Opratin shouted. "I'm sick and tired of fussing over you. You're nothing but a miserable dope addict!" "But who made me an addict? You're a scoundrel, that's what you are! Who procured the drugs for me? You did-because you wanted to hold me in the palm of your hand. But I'm not a finished man yet. I'll go into hospital and- And you can go to the devil! You may take 'The Key to the Mystery' with you for all I care!" "Get out of here! We're returning to town at once." "I should say not. I'm going to finish my latest experiment. I'll go down below now, rest a while where it's cool, and then-" The voices fell silent. The two men must have moved to a different room. "Did you hear that?" Yura whispered eagerly. "They have Fedor Matveyev's knife and 'The Key to the Mystery'. We were right. They were the ones who stole 'The Key to the Mystery' from the Moscow museum." "Keep quiet!" They waited, listening intently. "Look here, Nikolai. We must come out into the open. There's something very fishy about the whole thing." "It doesn't smell fishy to me. It smells of ozone." "Ozone?" Yura sniffed. The air coming up through the ventilation shaft had a fresh smell as if before a thunderstorm. "High voltage-" he muttered. The door on the other side of the pillbox squeaked as it was opened and then slammed shut. Bending low, Nikolai ran to the mud volcano, with Yura and Valery behind him. They returned to their first hiding place. They saw Opratin descend the slope to the beach, carrying a black attache case. He walked over to where Bugrov was working. "Why all of a sudden?" they heard Bugrov growl. "We were going to stay three days." Opratin said something that they could not hear. "Is he staying behind?" Bugrov asked. "Yes." "Wait a bit, until I put the engine together again." "Be quick about it." Opratin began to stride nervously up and down the beach. "What are we going to do, Nikolai?" Yura whispered. "Are we going to wait till they return for Anatole?" "The devil only knows when they'll come back. We can't wait." "Then let's go down to them now. At least one of us could return to town with them." "I don't want Opratin to know we're here," said Nikolai. "He'll get the wind up if he sees us here and he'll play some dirty trick on Anatole." "But why couldn't Valery go down to them and say he was shipwrecked? Opratin doesn't know Valery." "No, we'll do it differently. He'll never suspect anything." Yura stared at his friend, blinking in puzzlement. "Valery, be a pal and run down to the camp for the scuba gear," said Nikolai. "Bring some vegetable oil too. We'll be waiting for you over there." "What are you planning?" Yura asked. "Are you going to-" Nikolai nodded. "Yes, I'll hide underneath the boat and-" "You're mad!" "Run along, Valery, and be quick about it. Not a word to the girls, mind you!" Valery gulped in bewilderment. "No, of course not." He raced round the mud volcano, clambered down the slope to the east shore and ran towards the camp. "Don't be an idiot," Yura hissed. "It's fifty miles to town." "I know that," Nikolai replied calmly. "The cylinders are practically full. I'll tie myself under the bow of the boat and breathe through the snorkel." "You'll freeze before you're halfway there." "I'll cover my body with vegetable oil." Yura raised himself on his elbow. "I won't let you do it. I'll tackle Opratin. To hell with him-" Nikolai pushed him down hard. "Don't worry about me," he said. "I'll be all right. After we leave, you go in to Anatole and talk to him. Tell him Rita is here. I'll get Mehti to send a launch for you this evening. Or tomorrow morning, at the latest. Okay?" Yura knew it was useless to argue. They crawled over to the opposite slope of the big crater, from which streams of warm mud were flowing, and descended to the beach on the east coast. Valery came running up. Nikolai took the bottle, poured some of the oil into the palm of his hand, and began to rub it into his skin. His body soon became shiny and slippery. He looked at the pressure gauge on the aqualung and found that it stood at 140 atmospheres, which meant it was almost full. Yura helped him to strap the cylinders to his back. "Well, here we go." Nikolai squeezed Yura's hand, then shook hands with Valery. "See you soon, boys." "Be careful, Nicky." Yura could say nothing more. He looked miserable. Nikolai clapped him on the shoulder and grinned. He moistened the mask in the sea and clamped his teeth on the mouthpiece. From the mouthpiece two goffered hoses led to the cylinders, while a snorkel for ordinary breathing led upwards. Nikolai put on the mask, which covered his nose and eyes. He tied a length of rope around his waist, walked awkwardly down to the edge of the beach in his flippers, and entered the water. When he had waded in up to his chin he switched on the cylinders, dived straight down and then swam along the shell-strewn bottom. He rounded the steep headland and entered the cove. Using his air supply sparingly, he slowly swam along the shore until he saw the dark bottom of the motorboat. He swam under the boat, cautiously running his hand along the slimy bottom. At the bow his fingers encountered the lifeline hanging from the starboard side. The motorboat rocked and settled deeply in the stern. The two men had evidently climbed in. "If only they don't notice the bubbles," Nikolai thought as he took a firm grip on the life line. CHAPTER FIVE IN WHICH IMPORTANT EVENTS TAKE PLACE ON IPATY ISLAND Yura and Valery stood on the shore, silently watching the air bubbles that marked Nikolai's movement under water. The silence of the cove was broken by the roar of the outboard motor. Yura gave a start, then turned and began to climb up the slope. Pebbles rattled under his bare feet and sand trickled down. From the slope of the big mud volcano Yura and Valery watched the motorboat leave the cove and disappear round the headland. When it came into sight again the motor was droning steadily. Its bow rising into the air, the boat rapidly moved away from the island. Through the binoculars Yura saw Bugrov and Opratin, both in the stern. A head in a mask jutted out of the water at the bow. "He's sitting pretty," Yura muttered. "Boys! Where are you?" came Val's voice from the middle of the island. Val and Rita appeared on the crest of the next slope. Yura rose and waved to them. The girls climbed up the side of the mud volcano. "We heard a noise," said Rita, breathing hard. "It sounded like a motorboat." Valery pointed towards the motorboat, now a dark streak against the blue water. "A boat?" Val asked in astonishment. "Is it coming in?" "No, it's going out." "Why didn't you signal?" "Where's Nikolai?" Rita asked. "I'll tell you all about it." Yura gave them a brief run-down of the day's events on the island. "You say Anatole's in there?" Rita sprang to her feet and raced to the concrete dome. She jumped down into the depression in front of the entrance to the pill-box, then paused to catch her breath. Her face was pale through the suntan. A lock with a lead seal dangling from it hung on the steel door. The others came running up. "It's locked," Valery said. "How could that be?" "Anatole must have changed his mind and left with the others," said Yura. "Actually, we didn't see them getting into the boat." "No, we didn't see them getting in but-" Yura interrupted him. "He was probably lying in the bottom of the boat resting." "But what if Opratin locked him in?" Rita pounded on the steel door with her fists. "Don't start inventing things," Yura said sternly. "They quarrelled, I know, but to lock him in- That's nonsense." "How did you ever manage to overhear their conversation?" Yura gestured with his head. "We were on the other side." They skirted the dome and came up to the ventilation shaft. "Anatole!" Rita shouted through the grating into the black maw of the shaft. "Anatole!" The hollow echo was followed by silence. "He went away, I tell you," Yura insisted. Meanwhile, his brain was working feverishly. "He could have come out later than the others- while we were outfitting Nikolai on the beach," he thought. "We didn't see him in the boat, but he might have been lying in the bottom for all we know." "I simply must get inside, Yura." "You mustn't break the seal." "I won't have any peace of mind until I see for myself." Rita's dark eyes were filled with fear. Yura looked away. He put his hand on the rusty ventilation grating. "Oh, to hell with it!" he exclaimed after a pause. He looked round. His eyes fell on an old, broken oar. He picked it up and thrust it between the rods of the grating. After pushing the oar up and down a few times he heard the grating creak and give. Valery helped him to pull one end of the loosened rods out of the concrete and bend them upwards. The opening into the shaft was now wide enough to crawl through. "I'll go first," Valery volunteered. "No, you stay here. Rita and I will crawl in," said Yura. "Rita, you really oughtn't to, of course. You'll scratch your arms and shoulders badly. But if you insist-" "We'll all crawl in," said Val. "Valery and I also want to see what it's all about." "I'll swear everyone's off his rocker today!" Yura exclaimed. "Well, I can't do anything about it. Hand me a rope, Valery." He tied the rope to the concrete pipe and dropped the end into the shaft. "I'll signal who's to go when," he said. "You'll come down last, Valery." Yura wriggled through the opening, crawled into the cool darkness and began to slide down the rope. Before he knew it he had scraped his shoulders and elbows on the rough concrete. The camera banging round his neck interfered with his movements. The shaft was no more than two and a half metres deep, after which it levelled out into a horizontal passageway. Pressing against the concrete, Yura moved forward, feet first. Soon his feet reached empty space. Bending forward, gripping the rope tightly, he lowered himself into a dark room. When his feet touched the floor he rose to his full height and wiped the sweat from his face with the back of his hand. After his eyes had adapted themselves to the darkness he saw shelves of instruments in the faint light that entered the room through the ventilation shaft. He took a cautious step forward but stubbed his bare toe against something hard. He swore out loud. The hard object was a table leg. He ran his hand over the top of the table, feeling papers, books and some kind of blocks. At last, a table lamp! Yura pressed the button and light filled the room. He glanced round curiously. "Did you switch on a light?" Rita called from above. "May we come down?" "Yes, come down," Yura shouted back. He stepped over to the shaft opening that yawned in the low ceiling and explained how to crawl down. Rita was the first to appear. Yura helped her crawl out of the shaft. "Have you looked round?" she asked, letting her eyes run over the room. "No, not yet. Wait a while." Val crawled out of the shaft, followed by Valery. All four were badly scratched. Their tanned arms and legs were covered with white streaks. They looked about. Electrical instruments, optical instruments, jars of chemicals, panels of electronic dials and a great deal of other laboratory equipment lay on the shelves that lined the walls. The long table was piled with books, white blocks and rolls of squared paper covered with charts. A canvas folding chair completed the furnishings of the room. "We mustn't touch anything," Yura warned his companions. His face was grave; a worried wrinkle lay between his eyes. It was clear he felt a deep sense of responsibility. A narrow opening in the wall led into darkness. Rita resolutely headed towards the opening. "I'll go first," Yura said, putting out an arm to stop her. He carefully moved through the opening and descended a few steps. His fingers encountered a switch. Strong lights flared up beneath a vaulted ceiling, evidently the under-surface of the dome visible from outside. In the middle of the circular chamber stood an internal combustion engine connected with an electric generator. Yura leaned over to look at the trade-mark on the generator, and raised his head in surprise. It had a capacity of six thousand volts! "He's not here," said Rita. Yura recalled having heard Anatole say: "I'm going downstairs." He glanced round. There it was, a hatch in the concrete floor. He gave a strong tug at the ring, and the lid came up. Holding onto rungs in the wall, Yura descended the steps in the direction of a light. "You can come down!" he shouted as he stopped to look round. Two white columns that were insulators stood on the other side of a low partition. The tops of the columns went through the ceiling into a chamber where they were crowned by large metal spheres. In a deep hole at the foot of the columns there was an electric motor with a roller across which ran a wide band of silk. The motor was in operation. Yura heard the faint swish of the silk band as it passed over the roller. A smell of ozone came up from the hole. "Is that a Van de Graaff generator?" Valery whispered. Yura nodded. His mind was on something else. He could not understand why everyone had gone away and left the generator running and the lights on. Then his attention was caught by something else. A pile of thick discs about one metre in diameter, apparently plastic, lay beside the Van de Graaff generator on a support made of high-voltage insulators. On the top disc lay a sheet of copper from which an unbelievably thick cable ran to a white control panel. "Look at this!" Yura held out his Durandal screwdriver. The neon indicator bulb in the handle shone a bright red. "Don't touch anything, he warned. "This seems to be a battery of electrets with a colossal charge from the generator. Everything here is live." "Electrets?" Valery asked. "The things Koltukhov is investigating?" Yura did not reply. The situation worried him. "This is quite a voltage and quite a setup," he said to himself. He walked over to the white panel of instruments and levers. The face plates of cathode-ray tubes gleamed. Inside a coil beside the insulators hung a medium-sized knife with a yellowed handle. "My knife!" Rita exclaimed, moving towards the coil, her hand outstretched. "Get back!" Yura roared. "Are you mad? Look at this!" The bulb in the handle of the Durandal was blinking away for dear life. "This must be the main voltage node," Yura thought. "I wonder where those wires go." Wires ran from the coil to a large cage of vertical copper tubes. The cage was empty except for two rods, joined by a cross-piece, that jutted out of the concrete floor. A piece of cloth that looked like tarpaulin or canvas lay on the cross-piece. Yura brought his screwdriver up to one of the tubes out of which the cage was made. The indicator continued to light up. "What's that?" Val pointed to a half-open cardboard box lying beside the cage. Yura picked up the box. Glass ampoules sparkled in it. Before Yura had time to read the Latin name on the blue label Rita snatched the box from him. She gave the box one glance and then flung it away. Her lips quivered. She turned aside. Completely mystified, Val and Valery stared at her. Yura alone noticed that the box had fallen on the floor inside the cage-and had vanished. It had sunk into the concrete floor without leaving a trace. Yura stared dumbfounded at the spot where the box had fallen. This was penetrability! "I want that knife," he heard Rita say. He turned to her. "You mustn't touch anything." "But it's mine!" Rita's voice rose. "Besides, you said yourself that Anatole wanted to break with Opratin and take the knife with him." Yura shrugged. After all, it was her knife. "All right," he said. "But first I'll use my camera." He took several pictures of the mysterious cage, the wooden rods jutting up out of the floor, and the control panel with the knife and the coil. Then he carefully examined the apparatus. The wire that ran from the knife handle was plugged into a socket in the control panel. Yura pulled out the plug. After reading what was written above the buttons, he pushed one of them, in the middle of the panel. Cautiously he switched off the magnetic starter, then brought his screwdriver up to the coil. Now the indicator did not flicker. His heart beating fast, he released the coil that held the knife in place and drew it out of the spiral. "Is that Fedor Matveyev's knife?" Valery whispered, breathing down his neck. So this was Fedor Matveyev's knife! It had an ivory handle yellow with age, and a wavy pattern on the damask-steel blade, the blade that had slain the Incorporeal Brahman in the temple of the goddess Kali. Yura placed the palm of his hand against the cutting edge of the blade. His hand passed through the steel. Valery tried to seize the blade but his hand closed over emptiness. His eyes shone with excitement. Yura held out the knife to Rita. "Here you are. See that you don't lose it again. Are you satisfied now?" "I certainly am," Rita replied. "Anatole was here but he left. Let's go." "As soon as we return to town give the knife to Anatole," said Yura. "Otherwise you may land in all sorts of unpleasantness." "You're quite right." Rita's thoughts turned to Nikolai. "Isn't it awfully dangerous to hang in the water under a boat for such a long time?" "He'll hold out." They climbed the steps to the top floor of the laboratory. Yura looked at the table again. This time he noticed a small flat iron box half concealed by papers. One of the sides had been removed, so that the row of tenons of the dovetail joints seemed to grin menacingly at them. "This is it!" Yura exclaimed, seizing the box. "This is 'The Key to the Mystery'." Indeed, it was the last of the three boxes which Count Joseph de Maistre had sketched on the final page of Fedor Matveyev's manuscript, the box that had been stolen from the exhibition in Moscow. There was the familiar engraving on the cover: AMDG JdM "It's 'The Key to the Mystery'," Yura repeated, his voice solemn. "It should contain an explanation of the riddle of Fedor Matveyev's knife." "Oh, Yura, let's look inside it," Val pleaded. "Well, here goes. You are witnesses." Yura, pale with excitement, drew out a thick yellowed sheet of paper folded several times. The sheet did not rustle. "It must be parchment." "Yes, it is." Val fingered the sheet. "Calfskin. 354 My, how thin it is! Calfskin was used only for the most important documents." Yura unfolded the sheet. His eyebrows, bleached white by the sun, rose higher and higher. What he saw was a strange drawing of a seven-pointed star surrounded by circles, with radial lines, ciphers and symbols. "The zodiac, eh?" Yura muttered. "Let me look." Val took the parchment from him. "Why, it's a horoscope!" Yura was astonished. "A horoscope?" "Yes, and evidently the horoscope of some important person." Yura began to laugh. "What's so funny?" Val asked. "A horoscope," Yura groaned. "So that's what we've been hunting so long!" Laughter choked him. "That old scoundrel! He led us all up the garden path." Valery burst out laughing too, although he had only a vague idea of what it was all about. "Who's a scoundrel?" he asked, still laughing. "Count Joseph de Maistre." Yura had calmed down somewhat. "He was the one who called a horoscope 'The Key to the Mystery'." Val did not share their merriment. "Stop giggling," she said. "This might be some kind of a code. There are Latin words at the bottom." The text under the horoscope started with the words Anno Domini MDCCCXV. "That's the year 1815," Val explained. "In the middle there's another date-MCMXV-the year 1915. A century between the two dates." "Look, there's something written on the back too," said Rita, who was examining the parchment. "What's this? Why, it's my name!" The other side of the parchment was thickly dotted with circles connected by lines. Theodor Matvejeff Æ 1764 was clearly written in the top circle. (The sign Æ means "died". -Ed. It is used in genealogies') Marguerite Matvejeff was written in the circle at the bottom. "This is the genealogy of the Matveyev family," Yura said thoughtfully. "Starting with that naval lieutenant and ending with you, Rita." Rita gave him a startled glance. "Do you mean to say the Jesuits have been spying on our family all these years?" "We'll soon find out." Yura took the parchment from her, folded it and put it back in the iron box. He closed the box and fitted the cover into place. "I'm taking this with me. It was stolen from a museum." He wound the chain attached to the box round the strap of his camera and looked about him once more. "Let's get out of here. You go first, Valery." Valery seized the rope, pulled himself up on it, and vanished into the ventilation shaft. Val followed him. When Rita went over to the wall and grasped the rope she suddenly turned to look at Yura. She was struck by the strained expression on his face. She followed his eyes but could see nothing except the folding chair. "What's the matter, Yura?" "Come, climb up," he said in a low voice. He was staring fixedly at the folding chair, at the two rods with a cross-piece over which canvas was stretched. Down below, inside the cage, the top of the same kind of folding chair was sticking out of the concrete floor. The chair had sunk into the concrete floor! In the same way as the box of ampoules but not completely. Yura shuddered. He squeezed his eyes tight and shook his head. No, it was impossible! It could not be! "Yura!" came Val's voice from the "shaft. "Yura, where are you?" Yura shook himself. He turned out the light, walked slowly to the wall and began to climb up the rope. The sun now hung on the very horizon. The slopes cast long shadows on the sand. "Do you suppose Nikolai is there by now?" Rita asked. "He must be," Valery said. "Why did he risk it?" "He's an excellent swimmer. Besides, you know how strong he is." Rita gave Valery a grateful look. They reached the camp. Their dinner hour was long past; it was time for supper. Suddenly Yura halted. "Where's Rex?" he asked. Putting two fingers in his mouth, he gave a long whistle. "Rex!" he called. The dog was nowhere in sight. "You go ahead and prepare supper," said Yura. "Valery and I will look for Rex." They found him on the shore of the southern cove, sitting at the very edge of the water. He turned round for an instant when Yura called to him, shifted his paws restlessly, and turned back to stare into the water. Yura and Valery ran down the slope to the beach and came to an abrupt halt. The cove was swarming with water snakes. Holding their heads above water, they were swimming out to sea. From higher up the beach more and more were slithering out of their holes and heading for the water. There were hundreds of them, all good swimmers. They were accustomed to migrating from island to island in search of birds' eggs, but such a mass-scale exodus was extraordinary. "It's all very strange, their deserting this island," said Yura. "Something is worrying Rex, too." He lay down on the beach beside Rex, and suddenly felt faint, wide-spaced earth tremors. What a damned island! "Let's go up to the big crater!" he cried, springing to his feet. "Rex, come with us!" Warm grey volcanic mud usually flowed slowly over the edge of the crater. Now the flow had stopped, and the mud was hardening. "The crater is closed," said Yura. "What do you know about that?" "Is it a bad sign?" Valery asked. "Yes, very." When the two young men returned to camp they found the girls busy round the fire. Val was telling Rita something about horoscopes, while Rita kept one eye on the fish stew. "No need to upset them," Yura thought. "It may all blow over. At least, we won't tell them till the launch arrives. It probably won't come this evening. Most likely tomorrow morning. I wonder how Nikolai made out. What a stubborn devil he is! And what a day this has been!" They ate the now unbearably tiresome fish stew in silence. Val sighed. "It seems impossible to believe we'll really be home tomorrow. Imagine-a hot shower, clean sheets, and food that doesn't taste of fish." "Just wait, Val," said Rita. She sat up straight, her body tense, listening. "I may be imagining things but it seems to me the earth is moving." For a time there was silence round the fire. "I may as well tell you," Yura remarked casually, removing a fishbone from his mouth. "Something's happening inside the earth. The craters, which are safety-valves for gas that is compressed by tremendous pressures, are blocked up. Now the gas is bubbling deep down inside the earth, seeking a way out-" "Where will it come out?" Val asked. "If we only knew! Or when- Perhaps a hundred years from now-or in a minute. On the whole, that's the situation." He rose. "Get your things together. We're moving out to the raft. We'll be safer there." It took them only half an hour to break camp. The population of Ipaty Island, with all its possessions, migrated to the raft. Time passed slowly. The underground rumbling suddenly grew much louder. Whimpering, Rex pressed himself against Yura's leg. All of a sudden the island rocked as a white pillar of gas flew up out of the moving ground. A shower of pebbles and chunks of clay drummed down on the raft. Fierce heat hit their faces. Fire flashed. A gigantic torch leapt skywards with a roar. CHAPTER SIX WHICH TELLS OF FIRE AND WATER Nikolai waited a few seconds after the stern of the motorboat settled into the water, then cautiously raised his head beside the bow, knowing that he could not be seen from where the men were seated. The boat had cast off. Nikolai could hear the clink of metal. Bugrov must be putting the ignition distributor back in place. "You're always in such a tearing hurry," Nikolai heard Bugrov grumble. "I didn't even have a chance to catch any fish. There's lots of fish here. See all those bubbles on top of the water?" "Stop chattering," came Opratin's hard voice. "They don't suspect anything," Nikolai thought. "I mustn't lose any time. I'd better make myself comfortable here under the bow." He quietly drew one end of his rope through the lifeline hanging over the starboard side. He ran the other end of the rope through the lifeline on the port side. Then he tied the two ends together under the water and thrust his arms through the loop so that the rope ran under his armpits. Now the two aqualung cylinders pressed against the bottom of the boat, with the keel beam between them. "Not bad at all," Nikolai thought, gripping the rope, his arms bent at the elbows. "It won't be so bumpy." The motor began to drone evenly, and the boat moved away from the shore, slowly at first, then faster and faster. The headland swam into view and vanished. As the boat ploughed forward its prow rose into the air, lifting Nikolai's head and shoulders out of the water. He now breathed through the snorkel to save the air in the cylinders. He calculated that the motorboat should cover the fifty miles to town in about five hours. The cylinders of the aqualung held about 2,000 litres of air. He had used up some two hundred litres swimming underwater to get to the motorboat. The aqualung could be used until the pressure in the cylinders dropped to thirty atmospheres. This meant the last four hundred litres could not be used. Near town he would have to drop off and swim underwater for ten minutes or so. That gave him 1,000 litres for the trip, in other words, half an hour's supply of air. It was to be used in case a head sea prevented him from breathing through the snorkel. He must try not to make unnecessary movements. Still, he could not get along on less than thirty litres of air a minute. Everything went well at first. Skimming above the smooth sea, Nikolai enjoyed the water that streamed round his body. His feet, supported by broad flippers, trailed behind. The cylinders on his back pressed firmly against the keel beam. But soon the boat encountered a head sea. The prow rose and fell, and Nikolai had to adapt himself to this by inhaling only when the prow was out of the water. Even so, water got into the snorkel now and then, and Nikolai did not always have time to clear the tube. Once, when the prow rose high out of the water, Nikolai saw, on his left, the sun shining brightly on black rocks surrounded by foamy white surf. He knew these rocks. He felt as though he had been under that keel, lashed by the waves, for an eternity. Yet they had only covered about five miles, one-tenth of the distance! Nikolai was getting used to meeting the waves head on, but his body was growing chilled from the wind and the water. Evidently the oil he had rubbed into his skin was being washed off. He felt colder and colder. The rope to which he was clinging cut into the palms of his hands. A sharp pain twisted the big toe of his left foot and quickly rose to his calf. With difficulty, he turned on his right side. Bending his knee and then straightening out his leg, he struggled desperately against the cramp. Suddenly he heard the motor slow down. The prow sank into the water. He was now submerged. The boat came to a stop. Breathing at once grew easier. The motionless water seemed much warmer. Nikolai cautiously thrust his head out of the water. "Why must you take a dip now?" he heard Opratin's irritated voice ask. "Why can't you wait?" "Why wait? It's hot," said Bugrov. "Just a quick dip. There's Bull Island on the 'left. That means we're halfway." "Only halfway? We're going very slowly today." "You're right," Bugrov agreed. "I wonder why." Opratin spoke again. "By the way, where did you pick up Anatole Benedictov in town?" "Where we agreed-at pier 16. Then we went to pier 24 to pick you up." "Was there anyone else on 16? Did anyone see you?" "I don't think so. Why?" "Oh, nothing. Hurry up and take your dip." The boat listed and there was a splash