Von Harben looked and saw an opening about the size of a man's head extending into the fissure beneath them.
"Thank Nsenene, the grasshopper, Gabula," cried the white man, "if that is the totem of your clan—for here indeed is a way to salvation."
Hurriedly the two men set to work to enlarge the hole by throwing out other fragments that had long been wedged in together to close the fissure at this point, and as the fragments clattered down upon the rocks below, a tall, straight warrior standing in the bow of a dugout upon the marshy lake far below looked up and called the attention of his comrades.
They could plainly hear the reverberations of the falling fragments as they struck the rocks at the foot of the fissure and, keen-eyed, they could see many of the larger pieces that von Harben and Gabula tossed downward.
"The great wall is falling," said the warrior.
"A few pebbles," said another. "It is nothing."
"Such things do not happen except after rains," said the first speaker. "It is thus that it is prophesied that the great wall will fall."
"Perhaps it is a demon who lives in the great rift in the wall," said another. "Let us hasten and tell the masters."
"Let us wait and watch," said the first speaker, "until we have something to tell them. If we went and told them that a few rocks had fallen from the great wall they would only laugh at us."
Von Harben and Gabula had increased the size of the opening until it was large enough to permit the passage of a man's body. Through it the white man could see the rough sides of the fissure extending to the level of the next terrace and knew that the next stage of the descent was already as good as an accomplished fact.
"We shall descend one at a time, Gabula," said von Harben. "I shall go first, for I am accustomed to this sort of climbing. Watch carefully so that you may descend exactly as I do. It is easy and there is no danger. Be sure that you keep your back braced against one wall and your feet against the other. We shall lose some hide in the descent, for the walls are rough, but we shall get down safely enough if we take it slowly."
"Yes, Bwana. You go first," said Gabula. "If I see you do it then, perhaps, I can do it."
Von Harben lowered himself through the aperture, braced himself securely against the opposite walls of the fissure, and started slowly downward. A few minutes later Gabula saw his master standing safely at the bottom, and though his heart was in his mouth the Negro followed without hesitation, but when he stood at last beside von Harben he breathed such a loud sigh of relief that von Harben was forced to laugh aloud.
"It is the demon himself," said the warrior in the dugout, as von Harben had stepped from the fissure.
From where the dugout of the watchers floated, half concealed by lofty papyrus, the terrace at the base of the fissure was just visible. They saw von Harben emerge and a few moments later the figure of Gabula.
"Now, indeed," said one of the men, "we should hasten and tell the masters."
"No," said the first speaker. "Those two may be demons, but they look like men and we shall wait until we know what they are and why they are here before we go away."
For a thousand feet the descent from the base of the fissure was far from difficult, a rough slope leading in an easterly direction down toward the canyon bottom. During the descent their view of the lake and of the canyon was often completely shut off by masses of weather-worn granite around which they sometimes had difficulty in finding a way. As a rule the easiest descent lay between these towering fragments of the main body of the cliff, and at such times as the valley was hidden from them so were they hidden from the watchers on the lake.
A third of the way down the escarpment von Harben came to the verge of a narrow gorge, the bottom of which was densely banked with green, the foliage of trees growing luxuriantly, pointing unquestionably to the presence of water in abundance. Leading the way, von Harben descended into the gorge, at the bottom of which he found a spring from which a little stream trickled downward. Here they quenched their thirst and rested. Then, following the stream down-ward, they discovered no obstacles that might not be easily surmounted.
For a long time, hemmed in by the walls of the narrow gorge and their view further circumscribed by the forest-like growth along the banks of the stream, they had no sight of the lake or the canyon bottom, but, finally, when the gorge debouched upon the lower slopes von Harben halted in admiration of the landscape spread out before him. Directly below, another stream entered that along which they had descended, forming a little river that dropped steeply to what appeared to be vivid green meadow land through which it wound tortuously to the great swamp that extended out across the valley for perhaps ten miles.
So choked was the lake with some feathery-tipped aquatic plant that von Harben could only guess as to its extent, since the green of the water plant and the green of the surrounding meadows blended into one another, but here and there he saw signs of open water that appeared like winding lanes or passages leading in all directions throughout the marsh.
As von Harben and Gabula stood looking out across this (to them) new and mysterious world, the warriors in the dugout watched them attentively. The strangers were still so far away that the men were unable to identify them, but their leader assured them that these two were no demons.
"How do you know that they are not demons?" demanded one of these fellows.
"I can see that they are men," replied the other.
"Demons are very wise and very powerful," insisted the doubter. "They may take any form they choose. They might come as birds or animals or men."
"They are not fools," snapped the leader. "If a demon wished to descend the great wall he would not choose the hardest way. He would take the form of a bird and fly down."
The other scratched his head in perplexity, for he realized that here was an argument that would be difficult to controvert. For want of anything better to say, he suggested that they go at once and report the matter to their masters.
"No," said the leader. "We shall remain here until they come closer. It will be better for us if we can take them with us and show them to our masters."
The first few steps that von Harben took onto the grassy meadow land revealed the fact that it was a dangerous swamp from which only with the greatest difficulty were they able to extricate themselves.
Floundering back to solid ground, von Harben reconnoitered in search of some other avenue to more solid ground on the floor of the canyon, but he found that upon both sides of the river the swamp extended to the foot of the lowest terrace of the cliff, and low as these were in comparison to their lofty fellows towering far above them, they were still impassable barriers.
Possibly by reascending the gorge he might find an avenue to more solid ground toward the west, but as he had no actual assurance of this and as both he and Gabula were well-nigh exhausted from the physical strain of the descent, he preferred to find an easier way to the lake shore if it were possible.
He saw that while the river at this point was not swift, the current was rapid enough to suggest that the bottom might be sufficiently free from mud to make it possible for them to utilize it as an avenue to the lake, if it were not too deep.
To test the feasibility of the idea, be lowered himself into the water, holding to one end of his alpenstock, while Gabula seized the other. He found that the water came to his waist-line and that the bottom was firm and solid.
"Come on, Gabula. This is our way to the lake, I guess," he said.
As Gabula slipped into the water behind his master, the dugout containing the warriors pushed silently along the watery lane among the papyrus and with silent paddles was urged swiftly toward the mouth of the stream where it emptied into the lake.