In a few minutes now, if all went well, they would be in possession of the treasure. More than once as they worked, Frank drew his field-glasses out of their case and scanned the surrounding wilderness of rocky chasms and swept the green jungle that lay stretched like an emerald ocean far below, but each time he replaced them with a sigh of relief. So far there was no sign of any rivals' approach, although Frank well knew that by this time Muley-Hassan must be upon his way to contest the boys' claim to the ivory.
As the last stone was chucked aside with a mighty heave by the combined forces the perspiring adventurers broke into a hearty cheer.
Beneath it was a wooden trap-door which had a ring placed in the middle evidently for the purpose of lifting it. Frank gave it a heft, but the weight was too much for even his wiry muscles; but when Ben and, Harry assisted him the door gave with a jump that threw them all to their feet.
Scrambling up in a second they rushed to the edge of the hole revealed by the uplifting of the wooden cover. What they saw showed them instantly that their wildest hopes had not been overdrawn. There, at their feet, lay a king's ransom in yellow ivory.
From the hole rose a fetid, sickening odor that at first was almost overpowering. It came from the rotting flesh that still adhered to the roots of many of the huge trunks.
With a cheer Harry was about to spring down into the aperture when Frank, with a quick exclamation, drew him back.
"Jump back for your life!" he shouted.
Harry was accustomed to obeying his brother in everything, and jump backward he did with an agility that would have done credit to a gymnast. Before he could ask a question Frank's revolver cracked and a little spit of dust shot up almost at his very feet.
There lay a tiny snake viciously wiggling about in its death agony, pierced through by Frank's bullet.
It was a rock adder—one of the deadliest of African snakes. Barely more than three inches in length, and a dull gray in color, it was small wonder that Harry in his excitement had not seen it as he was about to jump almost upon it.