"Get out of this by all means!" exclaimed the inventor. "If we stay in this hot ocean we will be boiled alive like fishes in a pot. Send the ship up, Washington!" Indeed it was high time. The thermometer marked one hundred and ten degrees, and was rising. The interior of the _Porpoise_ was like that of a steam laundry three times heated. Stripped to their undergarments the adventurers were obliged to lie down on the floor of the cabin where it was a little cooler. It was all Washington could do, used as colored people are to the heat, to go into the engine room, and start the machinery that emptied the tanks, so as to allow the ship to mount to the surface. The _Porpoise_ began to rise slowly, and to the suffering men and boys it seemed that she never went up so reluctantly. The heat was becoming unbearable. They could hear the water bubbling even through the steel sides of the submarine. CHAPTER XXX CONCLUSION Could they live to reach the surface? was the thought in the mind of every one. The heat was terrific. They were breathing in gasps. Professor Henderson went to the water tank, thinking to throw some of the fluid over himself and his companions, but he found it so warm that it almost burned his hand. "Keep up your courage!" exclaimed the inventor. "We will soon be at the top!" Almost as he spoke the _Porpoise_ bounded from the waves, and fell back in a splash of foam on the surface of the billows. They were at the surface. The professor rushed for the manhole and soon opened it. He crawled out on the deck, followed by the others. They breathed in deep breaths of the fresh air. The submarine continued to sail on. Every minute the sea seemed to boil more violently, until at last the waves were covered with a cloud of steam, through which it was difficult to observe where they were going. "Hadn't we better turn back," suggested Mark. "Our only hope is to press on," replied Mr. Henderson. "We may cross this zone of boiling water soon." He went into the conning tower to make an observation. He came on the deck the next minute, very much excited. "What's the matter? Are we sinking?" asked Andy. "We are directly over the south pole!" exclaimed the professor. "We have reached the goal! We have come to the spot hundreds of men have tried to reach! It has been left for us to succeed. Look at the deflecting needle!" They crowded into the conning tower to note it. The slender hand of steel stood straight up and down, indicating that the ship was over the south pole, one of the two chief centres of magnetism of the earth. "If we only dared stop to make some scientific notes and observations," said the professor, "we could render much valuable aid to the seekers after truth. But it would be sure death to stay in the boiling water!" "I guess we'd better be getting out of this if we want to reach home alive," spoke Andy. Indeed they were all suffering very much, for the heat from the water was awful.