CHAPTER XVI. BEYOND HUMAN IMAGINATION. As the crater was left behind, the water became more turbid, and flowed faster, carrying along with it the boat and its three adventurous occupants. “Max!” The voice sounded almost sepulchral in the darkness. “Yes, Ibrahim.” “Isn’t this horrible?” “It is, but we are gaining knowledge.” “I know enough of the fearful----” “And yet--perhaps what we don’t know is far more horrible.” “Don’t talk like that, or I shall go mad.” “Ha! ha! ha!” The laugh was from Selim. “I’ve got it. It is here. Great prophet, isn’t it beautiful?” “What are you talking about, Selim?” “This--look at it.” “Look at what? Isn’t it so dark that you could cut the very atmosphere?” “He has gone mad,” whispered Ibrahim. “I am afraid it is so.” No wonder! The strain was something frightful. It would require nerves of steel to withstand such a terrible tension. “Jewilikins! what’s that?” Some strange, slimy water monster had crawled into the boat and onto Max’s back. It was impossible to see what it was, and all that Ibrahim could do was to knock it off; but he almost fainted as he touched it. On went the boat, drifting just where the current liked to take it. There was no means of guiding or steering it. They were victims of their curiosity, without a chance of saving themselves. Again there was a glimmer of light, and the explorers rejoiced. But their pleasure was but for a moment. The darkness was preferable. It hid from them the horrors of the river they had to traverse. Monster lizards crawled up and down the slimy walls which confined the river to its bed. Fish, with wings, would fly from the water and strike the occupants of the boat as they passed by. Great crabs, the like of which have never been seen before, struggled on every little ledge of rock or piece of sandy ground. One big fellow had got into the boat, and was slowly devouring pieces of Selim’s leg. The poor Arab was unconscious, and it could only be a question of minutes before his soul would leave the mortal tenement. As Max and Ibrahim realized it they were almost frantic with fear. “Five when we started,” said Max, “but only three now, and a few moments more there will be but two.” Ibrahim’s face was as white as death. His pulses were beating so slowly that it was almost a miracle he lived. Suddenly his mood changed. His heart began throbbing and pumping out blood at terrific speed. The color of his face was almost purple, and as he tried to stand up in the little boat his head fell back, and Max only saved him by a hair’s breadth. Max was now alone. Ibrahim lived, but was not only helpless, but in his delirium, dangerous to himself and his companion. Selim was dead. It grieved Max to have to throw the body overboard, but that was the only course which could be adopted. Unstrapping the packages of food from the man’s back, he exerted all his strength and pushed the man overboard. It was horrible.