"The terrestrial atmosphere extends to a distance of 6,000 fathoms from the earth," replied the doctor. "With a very large balloon we could go a great height. Messrs. Brioschi and Gay-Lussac did so, but the blood gushed from their ears and mouth. The air could not be breathed. Some years ago two hardy Frenchmen, Banel and Bixio, also made an expedition into the higher regions, but their balloon split."
"And they fell down?" demanded Kennedy anxiously.
"Certainly; but, as scientific men ought to fall, without sustaining any injury."
"Well, gentlemen," said Joe, "you are quite at liberty to begin your tumbling; but, for my part, as I am merely a commonplace person, I prefer to remain in the happy medium, neither too high nor too low. There is no use in being ambitious!"
At 6,000 feet elevation the density of the air became sensibly diminished, sounds were with difficulty transmitted, and speaking was not distinctly heard. Views of objects became confused, the vision could not distinguish anything more than confused masses. Men and other animals became absolutely invisible. The roads became threads, and the lakes ponds.
The doctor and his companions were in a very abnormal state. An atmospheric current of great violence carried them over the mountains, upon whose summits the large snow-fields caused them some astonishment. The appearance of these mountains betokened some convulsion of the sea during the first ages of the world's existence. The sun shone in the zenith, and his rays fell directly upon these deserted summits. The doctor made an exact plan of these mountains, which are formed of four distinct elevations almost in a straight line, and of which the most northern is the longest.
The "Victoria" soon descended on the farther side of the Rubeho, and passed over a wooded region in which trees of a peculiarly dark green were freely scattered. Then came crests and ravines in a sort of desert, which approaches the territory of Ugogo. Lower down they sailed over yellow plains, scorched, fissured, and here and there amongst the desolation appeared saline plants and thorny bushes. Some coppices, not far removed from actual forests,
