And just here, as the Fates which had of late been pursuing them would have it, the worn travelers found themselves once more in the line of the hordes of migrating beasts.

Grôm’s heart sank. To reach the refuge of the 302 hills across the march of those maddened hordes was obviously impossible. Were his people to be forced back into the swamp, to resume the cramped and ape-like life among the branches? Having ordered the building of a half-circle of fire around a spur of the jungle, he climbed a tree to reconnoiter.

The river ran but a mile or two distant upon his left. Immediately before him the fleeing beasts were not numerous, consisting merely of small herds and terrified stragglers. Further out, however, toward the hills, the plain was blackened by the fugitives, who were thrust on by the myriads swimming the river behind them. Assuredly, it was not to be thought of that he should attempt to lead his people across the path of that desperate flight. But a point that Grôm noted with relief was that only certain kinds of beasts had ventured the crossing of the river. He saw no bears, lions or saber-tooths among those streaming hordes. He saw deer of every kind––good swimmers all of them––with immense, rolling herds of buffalo and aurochs, and scattered companies of the terrible siva moose, and some bands of the giant elk, their antlers topping the mimosa thickets. Here and there, lumbering along sullenly as if reluctant to retreat before any peril, journeyed a huge rhinoceros, stopping from time to time for a few hurried mouthfuls of the rich plains grass. But as yet there was not a mammoth in sight––whereat Grôm wondered, as he thought they would have been among the first to dare the crossing of the river. Had they kept on up the 303 other shore, hesitating to trust their colossal bulks to the current, or had they turned at bay, at last, in uncontrollable indignation, and gone down before the countless hordes of their ignoble assailants?

The absence of the mammoths, which he dreaded more than all the other beasts because of the fierce intelligence that gleamed in their eyes, decided Grôm. He would lead his people along to the right, skirting the swamp and marching parallel to the flight of the beasts, calculating thus to have the jungle always for a refuge, though not for a dwelling, until they should come to a region of hills and caves too difficult for the migrating beasts to traverse.

For several days this plan answered to a marvel. The fugitives nearest to the swamp-edge were mostly deer of various species, which swerved away nervously from the line of march, but at the same time afforded such good hunting that the travelers revelled in abundance and rapidly recovered their spirits. Once, when a great wave of maddened buffalo surged over upon them, the whole tribe fled back into the jungle, clambering into the trees, and stabbing down, with angry shouts, at the nearest of their assailants. But the assault was a blind one. The buffalo, a black mass that seemed to foam with tossing horns and rolling eyes, soon passed on to their unknown destination. And the tribe, dropping down from the branches, quite cheerfully resumed its march.

On the fifth day of the march they saw the jungle on their right come to an end. It was succeeded 304 by a vast expanse of shallow mere dotted with half-drowned, rushy islets, and swarming with crocodiles. After some hesitation, Grôm decided to go on, though he was uneasy about forsaking the refuge of the trees. Some leagues ahead, however, and a little toward the left, he could see a low, thick-wooded hill, which he thought might serve the tribe for a shelter. With many misgivings, he led the way directly towards it, swerving out across the path of a vast but straggling horde of sambur deer which seemed almost exhausted.

To Grôm’s surprise these stately and beautiful animals showed neither hostility nor fear toward human beings. According to all his previous experience, the attitude of every beast toward man was one of fear or fierce hate. These sambur, on the contrary, seemed rather to welcome the companionship of the tribe, as if looking to it for some protection against the strange pursuing peril. His sleepless sagacity perceiving the value of this great escort as a buffer against the contact of less kindly hordes, Grôm gave strict orders that none of these beasts should be molested. And the Cave Folk, not without apprehension, found themselves traveling in the vanguard of an army of tall, high-antlered beasts which stared at them with mild eyes of inquiry and appeal.

Marching at their best speed, the Tribe kept easily in the van of the distressed sambur, and more than once in the next few hours, Grôm had reason to congratulate himself upon his venture into this strange fellowship. First, for instance, he saw a herd of 305 black buffalo overtake the sambur host and dash heavily into its rear ranks. The frightened sambur closed up, instead of scattering, and the impetus of the buffalo presently spent itself upon the unresisting mass. They edged their way through to the left leaving swathes of gored and trodden sambur in their wake, and went thundering off on another line of retreat, caroming into a herd of aurochs, which fought them off and punished them murderously. It was obvious to Grôm, as he studied the dust-clouds of this last encounter, that the buffalo herd, here in the open, would have rolled over the tribe irresistibly, and trampled it flat.

Journeying thus at top speed toward that hill of promise before them, the travelers came at length to a wide space of absolutely level ground which presented a most curious appearance. It was as level as a windless lake, and almost without vegetation. The naked surface was of a sort of indeterminate dust-color, but dotted here and there with tiny patches of vegetation so stunted that it was little more than moss. Grôm, with his inquiring mind, would have liked to stop to investigate this curious surface, unlike anything he had ever seen before. But the hordes of the sambur were behind, pressing the tribe onwards, and straight ahead was the wooded hill, dense with foliage, luring with its promise of safe and convenient shelter. He led the way, therefore, without hesitation, out across the baked and barren waste, sniffing curiously, as he went, at a strange smell, pungent but not 306 unpleasant, which steamed up from the dry, hot surface all about him.

The first peculiarity that he noticed was a remarkable springiness in the surface upon which he trod. Then he was struck by the fact that the dust-brown surface was seamed and criss-crossed in many places by small cracks––like those in sun-scorched mud, except that the cracks were almost black in color. These things caused him no misgivings. But presently, to his consternation, he detected a slight but amazing undulation, an immensely long, immensely slow wave rolling across the dry surface before him. He could hardly believe his eyes––for assuredly nothing could look more like good solid land than that stretch of barren plain. He stopped short, rubbing his eyes in wonder. A-ya grabbed him by the arm.