The Shark and the Jellyfish: More Stories in Natural History

Incandescent Falls

177 Incandescent Falls Incandescent Falls cascades from the bluffs on the south shore of Hawaii Isle, tumbling directly into the waters of the tropical Pacific. It is a constant presence on this midocean archipelago, though it alters its flow and position from time to time, conforming to the ever-changing islandscape around it. On those rare nights when it flows at maximal strength, the cataract is mesmerizing to behold. The glowing torrent issues from the mouth of a cavern, and the arc of its momentum carries it out over rocks burnished in its reflected light. It continues across the narrow beach, slipping beneath the shoreline waves, the color fading from its base as it disappears below curtains of mist. Despite its massive volume, the luminous falls hisses only softly as it cascades off the island’s edge—its earthshaking potential muted. It does not sing with the sparkling voices of a stream tripping over rocks because it does not carry water. Incandescent Falls carries magma—molten basalt conveyed directly from the Earth’s interior—lava that flows with the speed of a waterfall but is much too dense to splash and burble like a free-falling forest cataract. This firefall is flame yellow throughout. On its surface it floats rock that would itself glow if set on the sand but that appears black against the even hotter river that carries it. Should the pulsing current throw a few of its golden drops up onto the face of the bluff, they will cool to a dull red as they solidify in place, building out the seawall. Standing to the side, you feel the heat of the Earth’s core on your cheeks and the palms of your outstretched hands. You hear the surf hiss and steam where it splashes against the cascade; flotillas of little pumice rafts are spawned from the quenching reaction, each raft cradling in its center a small glowing ember. Sputtering and sizzling like water dripped into a hot frying pan, they bob by on the waves as they set out across the sea for Polynesia. This uncommon cataract flows down the bluff at the edge of a landscape as surreal as the radiant river itself. For half a mile back from the bluff, the 178 Frozen falls. Ripples in a pahoehoe lava flow have turned to stone. terrain is flat black lava flow. This ground breathes and moves beneath a smooth, dark skin throbbing just below its surface with a system of arteries that carry the hot volcanic blood of a living landscape. Those pulsing arteries are lava tubes. They form around streams of lava that snake to the ocean from craters up the slope behind the expanse of seaside tableland. The ground below these lava flows is heated to 1,600 de- 179 grees, but the exposed top lava surfaces lose heat to the breeze that washes in from the ocean. The upper crust darkens and hardens, eventually solidifying while the molten rock continues flowing underneath it. Where the streams of lava level out, approaching the shore, the flow slows. The cooling upper layer consolidates and thickens, eventually forming an arch that roofs the length of the incandescent river—containing the flow in a stone conduit. The magma within is insulated from the air, so it stays hot and fluid. It can course unseen through these stone subways for miles, far from its sources on the slopes to the northwest, never stiffening until it meets the sea. Should the red-hot wells of magma above cease flowing , the lava would drain away, leaving empty tunnels in the rock. Abroad span of this rugged terrain precludes easy access to Incandescent Falls. Few actually witness the hypnotic rhythm of its surge as it issues from the mouth of a lava tube to blaze down the face of the bluff against the night. The nearest access road has been permanently buried under kilotons of spreading lava flow. Approach is possible only by a precarious trek on foot across the black plain. The surface of this lavascape alternates in texture, much of it slippery smooth, silvery black billows of ropy lava that some enjoy walking on barefoot. Elsewhere are brittle black cinders that quickly shred footwear, let alone feet. But after the hike across this plain, one may find the falls quiet—they are intermittent and sometimes don’t flow at all. That hike is a dangerous traverse...