"No human being ever sat for it, Ben," laughed Frank; "it's a mere freak of nature which has so disposed the mountain mass at this point as to give the semblance of what the map-maker terms The Upturned Face."
"Well, if I had a mug like that I'd turn it down instead of up before some one did it for me," was Ben's comment.
The Golden Eagle landed on a plateau about halfway up the mountain, beneath the upturned face. It made an almost ideal camping-place, considering the rugged nature of their surroundings. In one part of it a small grove of bananas and palms had taken root, and their smiling greenery offered a refreshing contrast to the dark oppressive gloom of the giant rock masses piled all about. From the center of this oasis in the rocky range bubbled a tiny spring of water as clear and cold as if it had been filtered and iced. Frank's first act was to send out a wireless to the River Camp, telling of their arrival.
"Well, thank goodness, we've got something green and pleasant to look at," remarked Ben, as they set about transforming the chassis of the Golden Eagle into a comfortable tent by means of running up the canvas curtains on the aluminum frames provided for that purpose. Thus equipped, the chassis served the uses of an improved tent, as the floor was well above the ground and out of all danger of the unwholesome, vapors rising from the ground and also the scorpions and other reptiles.
But if the oasis itself was a pretty spot, it was made doubly so by the contrast it afforded to the scenery surrounding it. On all sides shot up frowning walls of rugged black rock which seemed to have been torn and ripped in some remote period by a terrific convulsion of nature. In places, too, the rock masses seemed to have been seared by subterranean fires. Frank gazed upward at the terrific character of the scenery about them.
"We shall need the rope-ladder," he announced suddenly after a long silence.
"The rope-ladder?" inquired Harry, "what for?"
Frank laughed.
"I mean the rope-ladder we use in the Golden Eagle. As you know, the only way to locate the cache is to strike a direct line down from the nose of the upturned face. That will bring us to the small cairn or pile of rocks that marks the Arab's hiding-place."
"He could hardly have chosen a better," remarked Harry. "Who would ever guess, unless they had the key to the mystery, that these mountains held such a fortune in tusks."