Читать книгу Water, Ice & Stone - Bill Green - Страница 14

TWO

Water

Our house stood in a raw little valley, almost a hollow, heavy with work, the night shifts and the day shifts blending in dim bars. Men trading stories of the mills. Beyond the windows the hills rose up and attached themselves to the sky like green-striped awnings. The steep, narrow streets switched back on themselves, hairpin turns of red brick spiraling up. Visibility was a mile this way, a mile that way, the horizon always close, cluttered with chimneys, dark coal smoke in winter from the anthracite. I must have been seven when I first left this place for the sea. I think the ocean was the first real openness I had ever seen. It was the year after we had gone to the forest, when I felt so closed in by dark pines I could hardly breathe. “You’ll love the ocean,” my father said. “You can’t see to the other side.”

He found us a clapboard rooming house, the paint peeling and blistered from the salt air. You could taste the ions on your tongue, feel their charges as a rush of exhilaration that came out of nowhere. We unpacked in a tiny room and headed for the beach—Eugene and Elizabeth and I following closely in our father’s wake. The sky was brilliant, a few white clouds patterned above the sea. As we approached the boardwalk, I fell a step behind. I think I was afraid of what I would see, that it would not measure up. The planks steamed, reflected mirror light. I looked over the worn wood that was old and smooth, almost like glass. There was a dazzling expanse of white sand before me, trembling thin lines of surf the length of the world. Everything moved or seemed to move, to break into hot points of radiance. A billion coruscations dancing in the foreground of the sea. Everywhere water, the heaviness of light. My father was out there, barrel-chested, booming against the waves, his white T-shirt, which he never removed, fluttering around his waist. I just stood looking at it all, the glittering openness that went on and on, that opened my breath, watching his large pale arm wave us in.

WATER IS SUCH STRANGE STUFF—so ubiquitous we hardly see it. It might as well be invisible, like one of those weightless fluids that followed Newton into the Age of Reason: phlogiston, caloric, the luminiferous ether, all transparent and aflutter with light. I walk on any ocean beach and the sea takes me in, almost as a friend, a fellow creature, a member of the living clan of shapes and sizes and movement that stretches hopelessly deep into its profligate past. We seem to know one another, this sea and I. I enter, and it subsumes me into itself. I suppose I am nothing more than a thin jelly, a flood of cells, water sluicing in veins and pipes, nothing it has not seen before. It cannot distinguish where I begin and it leaves off. It senses me only as one of its own.

Indeed, we are watery reeds in a watery world. So much water bound in watery sacks. Even our minds and our very breath rise and fall on the watery tide: eighty percent of our brains and our lungs, sixty-five percent of our entire bodies. Water courses through us, bathes each cell. The moon tugs at these inner seas.

The Earth, too, is irrigated by water: seventy-one percent of its surface, 320 million cubic miles of it. And there is nearly half this much tied up as “water of hydration,” bound to the ions of solids in the Earth’s crust. An invisible sea. Once you leave Los Angeles on this journey south to the Pole, there is nothing but water—all the way to Antarctica. Perhaps there are a few brown island stones, as smooth as skulls down there, rising above the waves. But even the twin islands of New Zealand seem little more than Maori canoes in the vast Pacific. Beyond Christchurch there is nothing to speak of either but water, until you cross over Wilkes Land and Cape Adare and encounter … yes, more water, though now in the form of Antarctic ice, as far in every direction as the eye can see. (Stephen Pyne has said of “Greater Antarctica” that this is “a world derived from a single substance—water.”) Twenty hours aloft over the Pacific and you get some sense of what the surface Earth is really all about. Solid Ohio, with its browns and greens, its pastures and fences, seems little more than a cartographer’s fiction of soils, plants, and trees. From the observatories of space, from the dry moon itself, it is the signature and brushstroke of water that you see, a delicate blue wash across the Earth.

Most of this water is in the sea, of course, mixed there with the weathered salts of the continents as churning brine. The remaining fraction is fresh, but most of this is sequestered in ice caps, hoarded there by darkness and cold. What is not stored at the Poles occupies the more familiar niches of lakes and rivers, atmosphere and groundwater. The Antarctic ice cap alone is so vast a storehouse of water that if melted, it would charge the rivers of the world for more than eight hundred years. And the Gulf Stream, wide and sluggish, bringing improbable springtime flowers to fogbound New England coasts, carries in its flow twenty-five times as much water as all the Amazons, Congos, and Mississippis on Earth. When these numbers are taken in and sorted out, it would seem that the hydrosphere—the realm of water in all of its pooled and dropleted and vaporous and streaming forms—was prepared and apportioned more for pilot whales and penguins, anemones and seals, than for those of us who dwell upon land. “Make no mistake,” Varner once said, “water is ubiquitous and yet it is more precious than gold.”

And more magical. There is a delicacy and power to this fluid that rushes through our veins and our lives, that punctuates waking and dream with longing, whose pools are light among blowing sand, among dark forests and low hills, whose forms—solid, liquid, vapor—are legion. I remember the snows of Pittsburgh, how the flakes grew as they fell, how they thickened and slowed in the viscous air, how they built dangerously on the rooftops until the roofs creaked and bowed under the weight, how mountains broke and avalanched under the winter trees. Or much later, how the waves, bottle green, curled luminous and lifting over the coral shore. How I went down and could not come up under their load. Water is mass and power: its drop-by-drop accretion into flood, its sudden rush through the breached levee, the brown swarm of its carried silt whispering through the drowned corn.

Once, when the trees of Ohio were silver in morning, they spoke under the gentlest breeze, the clatter of their thin branches ice-cumbered and dazzling, red and green and blue, the spectrum laid out in winter sun. Whole trees with leaves of ice. Whole orchards ablaze in refracted light. When ice forms on a lake, the crystals shoot outward from the cold shore into the center, long fingers extended into pale November afternoons. Dew fixes on the surface of grass, beads in translucent spheres and shakes its silver skin. In the mountains of Montana they said three feet of snow had dropped in a single night. The trains stopped, the cars stopped, the passengers forgot time in rustic inns, sipped hot drinks by the window. The wide streets beyond the parted curtains became legends. Once in Arizona they said the dam might break, so much rain had fallen. Cloudburst after cloudburst. The whole town emptied, the cars moving slowly in lighted procession to high, safe ground. There were just a few of us left on the bar stools, singing, hiding our fear in drink and laughter. But the next day when I awakened there was sun. The waters had flowed off into the night, peaceful and calm, rolling away through the hot desert down to the sea. Skiing on the Great Divide, I saw my daughter Kate stop and shake snow from her left hand. “To the Pacific,” she said, laughing. And from her right hand: “To the Atlantic.” A great smile lit her face.

Water is everywhere, we just need to remember it. It is in the trees—hundreds of liters transpire each day from an ordinary elm, heaved as gentle fog into the sky. There are a billion billion molecules in a single flake of snow, which is why the great photographer W. A. Bentley, the “snowflake man,” could say that in forty-five years he had never seen two alike. And never would. Water is imbibed in the germination of seeds, a process that involves the uptake of water molecules by coils of cellulose and loops of starch. This “drinking in” can unleash tremendous forces; thus small seeds split rocks weighing tons. Water imbibed by wood can create a force a thousand times atmospheric pressure, which is why the Egyptians used wetted stakes to split limestone for the Pyramids.

The early Greeks thought that water was not only everywhere, it was everything: every material object, every stone and cloud, every citizen of Crete, was nothing more than water transformed. One substance per world. What economy! Thales of Miletus asked, “What is it that changes, what is it that lies beneath all that we see and feel.” Things come and go, wind turning to rain, rain to earth, earth to sea, the cycles like Ephesian winds blowing on forever. And yet something endures in all of this. Something is merely changing form. And Thales answered, “It is water.”

Philosophers say that Thales posed one of the truly great questions ever about the world. It was the question that began the quest—the quest whose conduct has affected us all, whose revelations and outcomes we still await. It is worth considering for a moment. Already in the sixth century B.C., a mind was driven to find unity in the “manifold of phenomena.” As a start, Thales proposed a kind of “primary matter” whose permutations and combinations, whose rearrangements in space, could account for all that we see. That he should have chosen water seems a triumph of observation. For it appears for all the world that water, when it freezes, can become stone; and when it vaporizes, rises into steam-white clouds, can become air; and when it flows to the sea, can yield up earth in trellises of dark loam as deltas; and when it appears as storm, can give rise to the skittering fire of lightning. So many forms and so many names.

Water is everywhere, so we take it happily for granted, think it somehow usual that rivers should drain the planet’s skin, that seas should lie in its basins and folds. That rain should come from the skies along with snow and mist and dew. But we know thousands of liquids. Tens of thousands. Among all of these, water is singular, almost preternaturally strange.

At what temperature, for example, should water boil? If we knew only the molecular siblings of water—hydrogen sulfide, hydrogen selenide, hydrogen telluride, all of which look like water when you write their formulas down—then we would expect water to boil near minus eighty degrees Celsius. The kettle would sing in the dark, frozen night of the world. If water behaved like its siblings, it would be a gas at Earth temperatures and the atmosphere would roll with its troubled cloud banks and the sea would be a hovering fog.

Even as a staid and proper solid, water is no more predictable. On a winter lake, ice and zero-degree Celsius water move atop the denser liquid below. There is nothing dramatic in this, or so it seems, until you think just how absolutely strange it is that solid ice should float. The way of the world is for solids to sink in their own liquids; for cooling lead or mercury or methanol to settle out of their own fluids and crystallize. Thus things freeze from the bottom up, the molecules of the solid becoming neatly packed, as dense as cannonballs on a town green. But ice is different. As it forms from the surrounding water, the molecules open outward, link in delicate lattices and structures, geodesic domes buoyant on the water below. Because of this simple, immensely complex fact, the winter lake lies protected by the solid phase of its own self, its heat sealed and safe from the chilling air above. Because of this fact, fish inhabit northern lakes.

The buoyancy of ice is borne of its expansion. Other substances, regardless of their state, shrink as they cool, and for the most part, it is true of water too. But below about four degrees Celsius, something quite unexpected happens. As the temperature edges further downward toward freezing, liquid water begins, almost incredibly, to distend. If we were to view its cooling in a fine tube, as the Florentine scholars of the seventeenth century did, we would be amazed to see the shrinking column reverse its travel and begin to move steadily upward. This expansion of water continues as the temperature is lowered to zero. Finally, as water freezes into solid ice, its volume increases even more. The increase is dramatic—a full nine percent over the volume of the liquid. I have seen water, frozen in a confined space, shatter steel, embed shards of metal in laboratory walls. And the very same thing happens when drops of water freeze in winter stone. The water expands, the stone breaks, and slowly the entire mountain falls.

So, if water behaved like a normal liquid, there would be no lakes in the Antarctic Dry Valleys, only blocks of ice. Water would solidify first at the bottom, along the sediments, as needles and fingers of ice. Every living cell would be gradually locked into stillness, into an eternity of cold. But as it happens, ice freezes and floats on the surface. The waters below are protected from the fierce winter night as though they were cosseted in wool. And beneath this ice, in the liquid water that moves below, things can live and much can happen.

Yet the anomalies of water are not limited to cold temperatures. With the exception of ammonia, water has the highest heat capacity of any liquid or solid on Earth. This means that it has a kind of thermal inertia—its temperature is not easily moved by heat. “A watched pot never boils,” we mutter impatiently. And from childhood we remember that the sidewalk puddle is always deliciously cooler than the scorched summer pavement on which it sits. Because water is so slow to warm (and to cool), it has a moderating effect on climate. Cities on the ocean enjoy cool summer breezes from the sea and mild, snowless winters. Surrounded on three sides by water, San Francisco has one of the most equable climates on the continent. In fact, from this single phenomenon comes the relative mildness and uniformity of much of our planet. The oceans store and distribute vast quantities of heat, shift it from the dazzling latitudes of the equator, move it north and south against the rims of continents; an ocean current a hundred miles wide can transport as much heat in a single hour as can be gotten from nearly 200 million tons of coal.

There are other properties of water with Earth-wide consequences. Unlike gases, which have a certain “springiness” to them, liquids can be compressed only with great difficulty. But of all liquids, water is the most compressible, its volume the most responsive to high pressure. And while this effect is slight and is difficult to measure with any but the finest laboratory instruments, its significance on a global scale is considerable. If the volume of water did not shrink at all under pressure, if water were truly incompressible, sea level would be sixty meters higher than it is today, and the land area of the Earth would be reduced by a full five percent. The Netherlands, the towers of Manhattan, all of Bangladesh, and the Maldives would be gone.

Even the very surface of water is unusual. It is the wet, stretched skin of a drum, and the evidence is all around us: A water strider darts across the silver-satin finish of a pond, creating only dimples on the unbroken fabric as it goes. A steel needle, gently placed, floats in a cup of afternoon tea and the higher density of steel is defied. The inept diver breaks the surface of a lake and for a split second there is a lash across the belly, a fierce sting, a redness that will not abate. It is this tautness, this same surface tension that coaxes water into droplets and spheres. The shape of falling rain, the shape of rain on windows, the shape of dew on a blade of grass, on a spear of barley—these roundnesses go back to that surface.

So too does water’s power to erode. A drop of water is a bullet fired at the Earth. It is a hard pellet with a hard skin. It can blast tiny fragments from the most solid rock. Rain breaks on the face of the mountain, shatters microlayers of stone, craters the stone with its force, carries it away as sand and silt. All night long the rain falls as hard as sand against the stone, and the stone, in time, disappears.

But among the extraordinary properties of water, perhaps none is more important than its power to dissolve whatever it touches. As if in answer to the alchemist’s prayer, water is indeed the universal solvent. It takes everything, to some smaller or larger extent, into its bulk and substance. Oxygen, nitrogen, and carbon dioxide from the air; calcium, magnesium, sodium, and potassium from the stone. The entire periodic table runs with water in every river and rill. The atmosphere lives in it as in a mirror. For these elements, water is the gathering place, the medium of their collusion, their joining and condensation, their prebiotic building into amino acids and proteins, into sacks of living matter. Because it can dissolve, it is the font of life. Because it can dissolve, it can move mountains.

A drop of water touches a crystal of salt. How common a thing this is. For a split second nothing happens: the crystal is sturdy and built to last. To melt table salt, to rattle the cubic cages its ions form, requires high temperatures, foundry temperatures, eight hundred degrees Celsius. Then, before you realize it, the salt is gone. Dissolved. Become part of a solution, no longer visible as a translucent cube. How, in contact with water, does sodium chloride glide into seeming non-being so offhandedly, with such insouciance and at such modest temperatures that the whole vanishing act appears to be pure presto-chango, solid substance one moment, then gone the next? Change of this order should require extremes: large objects dropping from the sky; blaring trumpets; blast furnaces. Grinning devils with pitchforks, at least. Surely something more respectably intense than cold water.

But there is this trembling at the heart of matter. It goes on and on. Like the molecules of water themselves, the sodium and chloride ions know no peace, chatter constantly at their moorings, yearn like the ships of Greece to be off and wandering. When a drop of water presses against the crystal face, it is as though a great tide had washed ashore. The ions are loosened and borne away, swept up in a flurry of molecules whose charged ends are turned just right for the task. The solid dissolves into invisible navies of charge, dissipates, diffuses, becomes a homogeneous mixture against which the forces of gravity cannot prevail.

Yet all of this talk about physical properties says nothing of water’s dynamism, its splendid life upon the Earth—its swift turning in storm and fog, its movement through rivers. No matter where it is, water is moving. It is always in passage, wanting to be elsewhere. Thus water evaporates from the sea, blows over the lands, hovers, condenses into spheres, falls, evaporates again, or trickles downward through the Earth into waiting reservoirs deep among the folded rocks; or runs off the land and back into the sea. We know the times, too, of water’s passage. We have measured these things: nine days in the atmosphere, a few years in lakes; a few hundred years in groundwater; a few thousand years in oceans; more than ten thousand years in the ice cap of Antarctica. Always moving. Yearning to be somewhere else.

We have a million names for water in passage, so many forms does it take. The forms are a kind of poem, a line through our lives: lake, river, stream, cataract, waterfall, ground fog, ice, shower, downpour, meander, deluge, spring, font, runnel, marsh, bog, fen, inlet, bight, bay, wave, billow, and swell. And many more. It is like a chant, each word a memory.

It is no wonder people have given their lives to water, to be on it, to use it, to take from its bounty. Sea captains, farmers, shell fishers, river pilots, singing gondoliers, painters, and poets must all know its moods and its ways. No less the limnologist, the geochemist, the oceanographer, the hydrologist, the engineer, the solution chemist, the teacher, and the writer.

No less N. Ernest Dorsey of the U.S. Bureau of Standards and Measures, who provides us, in 1940, with more than six hundred pages of data, equations, tables, and graphs. All on water. Much of it curious and fascinating. In one of Dorsey’s entries we find that two inches of ice will be strong enough to hold “a man or a properly spaced infantry,” and that four inches will support a horse and rider, as well as light guns. Ten inches of ice is sufficient to accommodate “an army, an innumerable multitude,” and fifteen inches will suffice to hold railroad trains and tracks. One astounding entry claims that “twenty-four inches of ice once withstood the impact of a loaded railroad passenger car falling sixty feet through the air,” but, alas, broke under the impact of the locomotive and tender.

Some of Dorsey’s most intriguing information is on color. Lord Rayleigh believed that the blueness of natural waters was most likely due to the reflection of the sky. But a colleague of Darwin, J. Y. Buchanan, took exception to this opinion, noting that “when quiet water, as in the screw well of the research vessel Challenger, is viewed vertically under such conditions as to exclude reflected sky, it appears to be of a beautiful, dark blue color.” In 1936, E. Petit solved the mystery when he determined that the blue of Crater Lake, Oregon, arises from light scattered by the water itself. But the most convincing report was written by Charles W. Beebe on his bathysphere descents into the open sea. At fourteen hundred feet, long after the blues of the sky had been lost, Beebe wrote exultantly that the “outside world was, however, a solid, blue-black world, one of which seemed born of a single vibration—blue, blue, forever and forever blue.”

There is surely enough beauty in the mere facts of the world. They are ten times over and more, a surfeit. Enough to go round and round. To burden us forever with delight. And yet, even breathless with this, we somehow need more. We must have more. Perhaps it is our tragedy, perhaps our hope. Whatever, we must know why, we must know what is behind it all. Behind the snowflake, the water strider’s dance, the lake steaming at dawn, the looming iceberg on the sea scrolled with death—just the sea itself, its very presence and being, that it is here on Earth at all, that it speaks, that its brilliantined surface blinds. And the life of the sea, life in reeds and tubes, a dense matting around the Earth—what unites these? The world is not just pieces and fragments, not just glowing embers of fact, surfaces, baubles and trinkets and gold doubloons, marvelous though these surely are. It goes down and down, deep into dark wells below our seeing, into mystery and dream, then opens in chambers of startling light. Thales knew this. And Lucretius. And Dalton. And Bohr. But who are we, that we must enter these secret places far below the surface of things? The god of the wind, the god of the mountain, the god of the crops, the god of the light-filled sea. Who is the God behind these, the God from whom all these others come?