“But,” said the Scotchman, “how are you to make sure of the identity of this river with the one recognized by the travellers from the north?”
“We shall have certain, irrefutable, convincing, and infallible proof,” replied Ferguson, “should the wind hold another hour in our favor!”
The mountains drew farther apart, revealing in their place numerous villages, and fields of white Indian corn, doura, and sugar-cane. The tribes inhabiting the region seemed excited and hostile; they manifested more anger than adoration, and evidently saw in the aeronauts only obtrusive strangers, and not condescending deities. It appeared as though, in approaching the sources of the Nile, these men came to rob them of something, and so the Victoria had to keep out of range of their muskets.
“To land here would be a ticklish matter!” said the Scot.
“Well!” said Joe, “so much the worse for these natives. They’ll have to do without the pleasure of our conversation.”
“Nevertheless, descend I must,” said the doctor, “were it only for a quarter of an hour. Without doing so I cannot verify the results of our expedition.”
“It is indispensable, then, doctor?”
“Indispensable; and we will descend, even if we have to do so with a volley of musketry.”
“The thing suits me,” said Kennedy, toying with his pet rifle.
“And I’m ready, master, whenever you say the word!” added Joe, preparing for the fight.
“It would not be the first time,” remarked the doctor, “that science has been followed up, sword in hand. The same thing happened to a French savant among the mountains of Spain, when he was measuring the terrestrial meridian.”
“Be easy on that score, doctor, and trust to your two body-guards.”
“Are we there, master?”
“Not yet. In fact, I shall go up a little, first, in order to get an exact idea of the configuration of the country.”
The hydrogen expanded, and in less than ten minutes the balloon was soaring at a height of twenty-five hundred feet above the ground.
From that elevation could be distinguished an inextricable network of smaller streams which the river received into its bosom; others came from the west, from between numerous hills, in the midst of fertile plains.
“We are not ninety miles from Gondokoro,” said the doctor, measuring off the distance on his map, “and less than five miles from the point reached by the explorers from the north. Let us descend with great care.”
And, upon this, the balloon was lowered about two thousand feet.
“Now, my friends, let us be ready, come what may.”
“Ready it is!” said Dick and Joe, with one voice.
“Good!”
In a few moments the balloon was advancing along the bed of the river, and scarcely one hundred feet above the ground. The Nile measured but fifty fathoms in width at this point, and the natives were in great excitement, rushing to and fro, tumultuously, in the villages that lined the banks of the stream. At the second degree it forms a perpendicular cascade of ten feet in height, and consequently impassable by boats.
“Here, then, is the cascade mentioned by Debono!” exclaimed the doctor.
The basin of the river spread out, dotted with numerous islands, which Dr. Ferguson devoured with his eyes. He seemed to be seeking for a point of reference which he had not yet found.
By this time, some blacks, having ventured in a boat just under the balloon, Kennedy saluted them with a shot from his rifle, that made them regain the bank at their utmost speed.
“A good journey to you,” bawled Joe, “and if I were in your place, I wouldn’t try coming back again. I should be mightily afraid of a monster that can hurl thunderbolts when he pleases.”
But, all at once, the doctor snatched up his spy-glass, and directed it toward an island reposing in the middle of the river.
“Four trees!” he exclaimed; “look, down there!” Sure enough, there were four trees standing alone at one end of it.
“It is Bengal Island! It is the very same,” repeated the doctor, exultingly.
“And what of that?” asked Dick.
“It is there that we shall alight, if God permits.”
“But, it seems to be inhabited, doctor.”