“Absolutely so. The sources of the White Nile, of the Bahr-el-Abiad, are immersed in a lake as large as a sea; it is there that it takes its rise. Poesy, undoubtedly, loses something thereby. People were fond of ascribing a celestial origin to this king of rivers. The ancients gave it the name of an ocean, and were not far from believing that it flowed directly from the sun; but we must come down from these flights from time to time, and accept what science teaches us. There will not always be scientific men, perhaps; but there always will be poets.” “We can still see cataracts,” said Joe. “Those are the cataracts of Makedo, in the third degree of latitude. Nothing could be more accurate. Oh, if we could only have followed the course of the Nile for a few hours!” “And down yonder, below us, I see the top of a mountain,” said the hunter. “That is Mount Longwek, the _Trembling Mountain_ of the Arabs. This whole country was visited by Debono, who went through it under the name of Latif-Effendi. The tribes living near the Nile are hostile to each other, and are continually waging a war of extermination. You may form some idea, then, of the difficulties he had to encounter.” The wind was carrying the balloon toward the northwest, and, in order to avoid Mount Longwek, it was necessary to seek a more slanting current. “My friends,” said the doctor, “here is where _our_ passage of the African Continent really commences; up to this time we have been following the traces of our predecessors. Henceforth we are to launch ourselves upon the unknown. We shall not lack the courage, shall we?” “Never!” said Dick and Joe together, almost in a shout. “Onward, then, and may we have the help of Heaven!” At ten o’clock at night, after passing over ravines, forests, and scattered villages, the aëronauts reached the side of the Trembling Mountain, along whose gentle slopes they went quietly gliding. In that memorable day, the 23d of April, they had, in fifteen hours, impelled by a rapid breeze, traversed a distance of more than three hundred and fifteen miles. But this latter part of the journey had left them in dull spirits, and complete silence reigned in the car. Was Dr. Ferguson absorbed in the thought of his discoveries? Were his two companions thinking of their trip through those unknown regions? There were, no doubt, mingled with these reflections, the keenest reminiscences of home and distant friends. Joe alone continued to manifest the same careless philosophy, finding it _quite natural_ that home should not be there, from the moment that he left it; but he respected the silent mood of his friends, the doctor and Kennedy. About ten the balloon anchored on the side of the Trembling Mountain, so called, because, in Arab tradition, it is said to tremble the instant that a Mussulman sets foot upon it. The travellers then partook of a substantial meal, and all quietly passed the night as usual, keeping the regular watches.