The raft described an arc of the pool, slipped out of the boiling churn, and, before Christopher was aware, caught an eddy and went swinging and lurching in behind the cataract. The man so strong in both soul and body threw up his hands in the surrender of terror, for a thing more awful than the red light and the waterfall confronted us. He dropped the pole. Its middle struck the edge of the raft, and our one weapon of defense rebounded into the water. Beelo saw the catastrophe. He clutched me frantically about the neck, nearly strangling me before I broke his hold.
Christopher looked about for the pole, and saw it bobbing on end as it struggled against submergence in the down-thrust behind the fall. It was twenty fatal feet away. The ferocity of elemental self-preservation seized on the man and transformed him. This was not the attitude of patient, gentle Christopher, the humble, serving Christopher, but that of a bayed animal. My hands were tied by the necessity of Beelo’s care.
The spectacle that had unmanned Christopher was in a profound recess reaching indeterminately out of the cavern and behind the waterfall. It had not been visible until we rounded the fall and went scurrying behind it in the eddy. Apparently far back,—I cannot guess how far,—ran a broad, high, fantastically irregular tunnel ending in a pit of boiling lava, at an unknown depth below the level of the tunnel, which itself was slightly above the surface of the pool. Deep rumblings issued from it, as from a heavy ebullition, punctured with smothered detonations. Rising from it were thin, cloud-like masses of vapor, like the pale mauve haze of distant mountains. In its rolling it thickened concealingly here and opened revealingly there, with constantly shifting effects.
The dominant color was a deep, transparent crimson of a tint such as may be seen in the cooling iron of a foundry or in the great crater of Kilauea; but following the detonations came leaping flames of bluish purple. It was the red shining through the water that had made the cataract a fall of liquid crimson when seen from the front.
This, then, was the funnel of a volcano, with a lateral vent. Was it one of Pluto’s cooling forges? Was its present activity transient? Was this the beginning of a seismic convulsion that might blow the valley rampart into the sea?
I cannot say when those questions arose. The urgency of an immediate threat demanded all attention. Beelo was in an ecstasy of terror, and Christopher was desperately casting about with all his reassembled wits. In the tumult of noises our voices were useless. We had been flung out of the larger eddy into a smaller one swirling between the back of the fall and the tunnel-mouth. It had a swifter and more dizzying whirl. Soon it seemed that we were still, except for the ceaseless rolling of our craft, and that the roaring fall and the grumbling, blazing tunnel were swinging round us. With the rest passed the bobbing pole, a live, insane thing, nodding this way and that, approaching the downpour gingerly, diving under a sharp water-blow, and leaping up with malicious sprightliness a few feet back. At any moment it might be caught sidewise and crushed.
There was another danger. The centrifugal force of our swing in the eddy was carrying us out to the periphery of the swirl. On one side were the rocks at the mouth of the tunnel; opposite was the waterfall, the slightest blow from which (since it fell from a height of at least a hundred feet) would mean the end. Our swinging was taking us nearer to both those dangers.