The pack dropped4 off his back and fell away into the darkness.

Relieved of the weight, Sean tottered and swayed. Then, with both arms free, he grabbed wildly at the edges of the rock crack and managed to keep himself from plunging after his pack into the abyss.

He clung to the rock and listened to the pack striking the cliff as it fell, the steel of his rifle barrel ringing like a bronze bell off the rock, waking the echoes and sending them bounding from kopJe to cliff, a terrifing sound in the night. Long after the pack and rifle had come to rest at the base of the Cliff, the echoes still reverberated against the hills.

Sean swung himself sideways and was able at last to wedge his shoulder into the crack. He rested like that, panting wildly, the terror of death for the moment unnerving him. Then slowly his breathing eased and his terror was replaced by the familiar glow of adrenaline in his blood. Suddenly it felt very good still to be alive.

"Right to the very edge," he whispered hoarsely. "You have been there again, boyo." The greater the terror, the more intense the thrill. He no longer amazed himself, but here he was again gloating at just how close he could get without going over the edge.

The thrill was too fleeting. Within seconds it began to fade, replaced by a realization of his position. His pack was gone. The rifle, water bottles, sleeping bag, food, all gone, All that remained were the contents of his pockets and the tiny emergency pack and hunting knife looped to his belt.

He whispered, "We'll worry about that when we get to the top."

He began to climb again. With one shoulder wedged into the crack, he was able to push and drag himself upward an inch at a time, paying for it with skin from his knuckles and bare knees.

Gradually the crack continued to open wider, until it became a full chimney and he could get his whole body into it and double one leg under him to propel himself upward more swiftly At the op the chimney had eroded and crumbled. One side wall of the chimney had broken away, but it had left a narrow buttress with a flat top. Sean was able to transfer his weight across the chimney utntil he was standing on this precarious pinnacle.

The top of the cliff was still ten feet above his head. When he reached up to the full stretch of his arms, standing on the tips of Ms toes, the ledge was stiff just out of reach. The chimney wall had broken away clearly, leaving a smooth, almost polished surface without even the minutest hold or purchase. A good, safe climber moved from hold to hold with never a single moment when he was totally insecure. In a situation such as this that hypothetical climber would have driven an iron piton into the rock to give him the hold he needed.

"Look, Mummy, no pitons," Sean said grimly. "We'll have to jump for it." He would have only one chance at it. If he missed his hold on the ledge once he had launched himself, the next stop would be the base of the cliff.

He set both feet firmly and sank down at the knees, but he was so cramped on the tip of the buttress that he could not get low enough before his face touched the rock and his backside stuck far out over the drop. He took a breath and used both arms and legs to propel himself straight upward. It was an awkward, hampered jump, but he got high enough to hook both hands over the edge.

For a moment they began to slide back, then his fingers gripped and held.

He kicked both legs and drew himself upward by the main strength of his arms. His chin came level with the ledge, and in the moonlight he saw in front of him a false crest, simply another ledge below the true top of the cliff.

The ledge was obviously occupied by a colony of rock hyrax.

The stink of their droppings, sharp and ammoniac al filled Sean's lungs as he gasped from the effort of holding himself. The hyrax is a plump, fluffy animal. Although it is only the size of a rabbit, it is a remote relative of the elephant and as endearing in appearance as an infant's soft toy. These hyrax were deep in their rocky burrows now, and the ledge seemed deserted. Sean hoisted himself up smoothly and hooked one elbow over the edge; he kicked again, gathering himself for the final effort. Then he froze.

The silence of the night was cut by a loud high-pitched hiss, like the leaking valve of a truck tire. In the moonlight what he had taken for a pile of rock lying directly in front of his face altered shape, seeming to melt and flow. In an instant Sean realized it was a snake. Only one of the adders would hiss as loudly, and only one adder was that large.

It was coiled upon itself, loop after loop of its thick scaly body glistening softly, and as it cocked its neck into a menacing "S" the moon and winked at him shape, its eye caught the light of sardonically.

The huge flat head was the distinctive spade shape of the ga boon adder, the largest of all the adders and one of the deadliest of all of Africa's venomous snakes.

Sean could drop back and try to regain his stance on the narrow pinnacle of rock, but that was a slim chance and if he missed it, he e ul would plunge down the cliff face. A much better chanc would be to try and brave it out.

He hung with legs free, trying to control his breathing, staring in horror at the loathgbme creature- It was cocked to strike less than two feet from 4is face, and he knew it could lunge out almost its full body length," seven feet or more The slightest movement would trigger it.

He hung on his arms, every muscle of his body rigid, staring at the adder, trying to dominate it by the force of his will. The seconds drew out as slowly as spilled molasses, and he thought he detected the first relaxation in the taut "S" of its neck.

At that moment his left hand slipped, his fingernails rasped on the rock, and the adder struck with the force Of a blacksmith's hammer.

Sean rolled his head to the side like a boxer avoiding a punch.

The adder's cold, scaly nose jarred against his jawbone and there was a fierce tug against his neck and shoulder, so powerful it jerked one hand loose from its hold on the rock and spun him half around. He was sideways to the ledge, holding on with only his left arm.