A Crack in the Edge of the World

by Simon Winchester

  For it should be remembered that every single one of those Old Geologists—the tweedy figures who, with hammer and lens and acid bottle, had explored and observed and thought and written since the days when it was first realized that the earth is actually very old and that rocks are laid down with some natural purpose and that no deity had anything much to do with the actual manufacture of the planet—found their evidence for the theories and principles of the Old Geology in the rocks, fossils, faults and minerals that were scattered around simply and solely on the surface of the earth. They made crucially important discoveries, true; they laid the foundations for this most elemental of disciplines, true; but they did so by examining only the topmost layers—or at most the topmost few miles of thickness, if you will—of the planet.

  And that, it is now realized, was a very limiting way indeed of conducting the science—a science that, after all, should more properly be concerned with the nature and history of the earth in its entirety, and not with its surface alone. Before the 1970s we had knowledge about the earth’s outer cover and not much more. What we wanted to know involved, if we thought about it, much, much more. We wanted to know—and geology was, in its theoretical essence, established purely so as to enable us the better to know—about the earth as a whole. And when the intellectual revolution of the sixties came about, we started swiftly to understand that up until that point we had, quite literally, only been scratching the surface; we had never considered the earth as it truly deserved to be considered.

  It promptly started to dawn on those sixties geologists who had listened to Tuzo Wilson or his acolytes, or who had seen the spacecraft pictures, that it was somewhat misleading for a science to draw conclusions about the earth entire by examining only those minor features that occurred upon, or just beneath, the planet’s outer covering. A fault in Scotland or the relic of a volcano in Montana or the succession of types of trilobite that had been found buried in a shale high on a hillside in British Columbia—such things might be interesting in and of themselves, but only when they were viewed in the context of the big picture, of the planet as a whole, were they able to offer up evidence that allowed the whole-earth portrait to be inked in and made to look something like complete.

  So this, then, lies at the heart of the New Geology. The world is these days viewed by most as one entire and immense system, the most refined of its details all interwoven with the biggest of big concepts. It is a living system four and a half billion years old. In a purely physical sense it is an entity warmed up from inside by radioactive decay, with fragments of its fairly recently cooled crust moving about on top of its more mobile inner self, and with solid rocks that have formed (or are still forming) on or beside these fragments creating continents or the floors of oceans. These rafts of solid rock have since been (or are still being) folded or lifted or broken apart as the plates on which they ride move about until they collide and bounce and dive beneath one another. In places, the rocks rise up to great heights; these are eventually eroded, causing the formation of sediment. Ageological cycle of creation and decay continues, endlessly. And meanwhile there is life, almost in global terms a brief irrelevance; animals and plants evolve and disappear by turns on the various wet or dry surfaces of the planet according to a series of complex sets of rules that have been laid down by the practical realities of tectonics, of temperature, of pressure, and of almost limitless quantities of time.

  The finer details of these things have been studied for decades—such arcane niceties as the suture lines of ammonites (by which one can determine the species and subspecies of this particular beast, which floated gently about in the Mesozoic seas), or the varying degrees of sphericity of the ooliths in a Jurassic limestone, or the patterns of those parts of bivalved creatures that are inelegantly known as muscle scars. But now, in the light of the whole-earth, big-picture view of the science of which they are so infinitesimal a part, they seem tangential to the broad realities of the New Geology, as the pores in an elephant’s skin do to a biologist or the volume of sap that courses through the leaves of a live oak from San Antonio does to a forest botanist.

  Which is not to say that such things are unworthy of our fascination. Small pieces of puzzles can often lead to grand ideas: The beaks of the Galápagos finches, after all, led Charles Darwin to his big notions about natural selection, the origin of species, and evolution. But it is important to remember that Darwin had at the time all of what was known of earth’s biology at his intellectual disposal—every beak and claw, every feather and fin was there, and his journeys took him to far and remote parts of our planet, so that he saw and thought about evidence from all manner of perspectives. When he sat down to write and think at his desk in Down House, he had an immense and almost unimaginable accumulation of information available to him, the finches’ beaks being just a scattering of tiles from the great mosaic of biological knowledge.

  But, by contrast, geology, at least before the 1960s, was able to lay out before its practitioners only the tiniest portion of available information—very little more than the superficial, the minute, the peripherally relevant. And then, in the nick of time (for without it, where would geology have gone?), everything altered: Along came the astronauts and the unmanned satellites and the space-born magnetometers and gravimeters and mass spectrometers and ion probes, and along came J. Tuzo Wilson and a whole army of like-minded tectonicists. They, combined with the new way of looking at the earth, taught the Old Geological community that there was much, much more to know—and what was once merely a hunch, an inner feeling, became a settled idea. It became abundantly clear that very few grand theories could actually ever be derived from minutiae such as ammonite suture lines and oolith sphericities and relative umbo sizes alone, except forensically; and that nowadays the grand geological ideas are the ones that truly matter.

  THE VIEW FROM ON HIGH

  And seen in that great and glorious context is the earth of the Californian morning of what Western Christian mankind had chosen to call April 18, 1906. Had any geologist at the time been able to look down at the planet in its entirety and witness what took place then, he would at the very least have been utterly amazed by the physical context of the event, even if the event itself, when viewed from on high, appeared less than overwhelming.

  For, as context, the planet would have been memorably beautiful. Had he been standing on the moon, say—had he been a 1906 version of Neil Armstrong, scanning with a hugely powerful telescope the surface of the blue and green and white ball that was hanging in his ink black sky—he would have seen illuminated in front of him (assuming that the cloud cover was not too dense) a tract of the world that extended from what some of mankind called India to what others called the Rocky Mountains, all of which would have been bathed in the brilliant white light of sunshine.

  He readily could have made out all of Europe and Africa, Asia Minor, and Arabia; he could have seen the deep blue of the Atlantic Ocean, the pure white mass of Greenland to its north, the blinding white immensity of the Antarctic deep below. The corpulent mass of what we now know as Brazil would have been sparkling in the sunlight, with the city-smudged eastern coasts of North America and Patagonia only slightly less so, places peopled with a humanity that was just waking on what many of earth’s inhabitants would call a Wednesday, a day that thousands of miles away, in the darkness of China and all points east, was in any case already coming to its end.

  At the moment that we find interesting—five o’clock in the morning, give or take—he could have seen the terminator line of western darkness pushing its way rapidly toward the Pacific. The earth would have been moving relentlessly at a speed of some hundreds of miles an hour eastward toward it, opening ever more populated parts of the landmasses to the light of the dawning day.

  The line at that very moment would seem to begin in the north near Melville Island in the Canadian Arctic, pass on down through Banks Island and the unpopulated and icebound wilderness of the Northwest Territories and the Yukon,
through Saskatchewan and Alberta, raggedly on down through the newly created state of Montana, through the bison-and-Comanche country of Wyoming and Colorado and New Mexico, across the Rio Grande toward Acapulco, and arrive at a point on the coast where it would finally slide off the North American landmass and eventually brighten the still-inky emptiness of the Pacific Ocean.

  To the east of the line, all would have been bright and daylight. To the west, an impenetrable dark. And on the line itself, an uncertain penumbra of a few hundred miles of a swath of half dark and half light. On earth this penumbral vagueness would have translated itself into the morning twilights that early risers were experiencing just then in cities and on farms and in small villages all the way from Vancouver Island in the north down to Baja California in the south, where the day designated as April 18 was about to begin.

  It is fanciful to suppose that anyone watching so far away, in distance or in time, would have had access to a telescope that was large enough to do the job. But, assuming that such a device did exist, and that the person at this lunar viewing point had its brass and glassware trained precisely on the northern coast of California at that very particular moment, with the terminator line brightening his view inch by inch—what, precisely, would he have seen?

  The answer is inevitably dismaying to all of those who like to think that the earth and its inhabitants and the events that occur upon it have any importance at all, in a cosmic sense. For from that distance he would have seen, essentially, nothing.

  Yet at a few minutes past five in the morning of that day something did, indeed, happen.

  The planet very briefly shrugged.

  It flexed itself for a few seconds, perhaps a little short of a minute. If our observer had been acutely aware of his geography, and if he had been fortunate enough to have been staring at a very precisely defined spot in the north of California at exactly the right moment, then he would have seen what appeared to be a tiny ripple spurt in toward the coast from the sea. He would, moreover, have seen that spreading ripple as it moved slowly and steadily inshore, and then watched as it moved, fanlike and subtle, up and down the coastline as a tiny shudder. It would have seemed to him a momentary loss of focus, something that would have made his vision suddenly blur very slightly, and then just as quickly clear again.

  If he had blinked, he would have missed it. Having noticed it, however, he would probably have assumed it was more of a problem with his lens and his telescope than with the surface of the planet below. And even if he had realized that the ripple and the shudder had in fact occurred on the green and blue and white planet that floated serene in the lunar sky, he would have been quick to conclude that whatever it was had been momentary, trivial, and utterly forgettable. No more, for the earth entire, than a gentle and momentary heave of the shoulders.

  THE STREET BEFORE MORNING

  It was all so very different down on the surface of the planet itself. On earth, in the western part of that great entity called by most English-speakers North America and particularly in and around the fragile and rather delicately constructed young northern city of San Francisco, a number of people grasped all too quickly that something of immense significance was happening. And if they were sensible and observant they took care to note and remember exactly when it all began, and we have their memories set down for us still.

  In the city it was a little after five by the local clocks and still not yet light (though some speak of a rosy glow just discernible behind the hill named Mount Diablo, to the east). The air was cold and moist in the way that spring mornings often are in Northern California. But there is a robust heartiness about those who choose to live in this corner of America, and, in spite of the chill and the gloom of this particular morning, a man of middle years, described in the directories simply as a laborer, was already in the sea taking his morning constitutional: This involved swimming through the rough-breaking waters of the Pacific, a few yards off the shore at Ocean Beach.

  At the same moment, five city miles away, a young reporter was walking home with two friends, having completed the routine tasks of what newspapermen were in those days starting to call “the graveyard shift.” He had stopped on Larkin Street near City Hall to smoke a cigarette and exchange pleasantries with a pair of patrolling policemen, and so further secure these necessary professional connections.

  A professor of geology—an immensely eminent man of sixty-three who had been honored around the world for painstakingly exploring and mapping the Rocky Mountains, the Grand Canyon, Death Valley, and a score of other remote and dramatic wildernesses besides—was lying asleep in a room at the Faculty Club at the University of California.

  The head of the City Weather Bureau, a future professor at Harvard College, an expert on frost, and at the time an enthusiastic advocate for naming the study of weather “aerography,” was also asleep, in his house at 3016½ Clay Street. But, as was his custom, he slept lightly, and kept a flashlight, a watch, an already-date-stamped notebook, and a pencil on the table beside his pillow so that he might be ready for whatever mayhem—aerographic or meteorological or otherwise naturally made—the night might throw at him.

  And an elderly English astronomer, the founder of the first real observatory in California, a man of great energy and yet one whose career had precipitated no little controversy and disappointment and who had just retired at the age of eighty-one from the post of professor of geography at the University of California, was lying half awake in his house at 2221 Washington Street, on that fashionable square in Pacific Heights known as Lafayette Park.

  AT THE PRECISE MOMENT when the members of this quintet—three of them very distinguished men of science and two others of relatively modest social standing—were undertaking their very mundane activities of swimming or walking or chatting or sleeping or drowsing, with most of them unknown to one another and each certainly unaware of the others’ exact circumstances at that second, it was twelve minutes after five o’clock in the morning.

  However, this was a matter of provable fact only for the Englishman, so far as the record relates. His name was George Davidson, and he, like his fellow scientists, wrote about the event that was to follow with a certain icy detachment. He took care to mark the time that he first noticed something happening: Suddenly and without warning his room, his house, and the very land all was standing upon began to shake, with a great, ever-increasing, and uncontrollable violence.

  It was, he knew full well, an earthquake.

  It came, he later reported,

  from north to south, and the only description I am able to give of its effect is that it seemed like a terrier shaking a rat. I was in bed, but was awakened by the first shock. I began to count the seconds as I went towards the table where my watch was, being able through much practice closely to approximate the time in that manner. The shock came at 5.12 o’clock. The first sixty seconds were the most severe. From that time on it decreased gradually for about thirty seconds. There was then the slightest perceptible lull. Then the shock continued for sixty seconds longer, being slighter in degree in this minute than in any part of the preceding minute and a half. There were two slight shocks afterwards which I did not time.

  Professor Davidson must have been as terrified as anyone, but he was a man trained to observe, and he knew in an instant what was taking place. So he took painstaking care to note that his watch, as he later reported, stood at 5h 12m oos. Only he then added the caveat, for safety’s sake—and with the sense of caution that was hardwired into his astronomer’s mind—that this observation was subject to an error of plus or minus two seconds. This reflected, one imagines, any error that he might have made when calculating how long he had spent staggering, his nightshirt awry and his mind still marginally befuddled by sleep, from his bed to the bureau where his watch was ticking and readying itself to slide, along with the pitcher and the shaving mug, onto the redwood floor.

  The first full series of hard shocks, say his notes, lasted until 5h 13m 00s. The shoc
ks were slightly less from that point until 5h 13m 30s, then there was a slight lull, and by 5h 14m 30s all was quiet again. The entire event—which was to destroy an American city and leave an indelible imprint on the mind of the entire nation—had lasted for just over two and a half minutes. That, at least, was the considered view of a man so esteemed that three mountains, a glacier, a seamount, an inlet, a bank, and a San Francisco avenue were later named after him. The official report on the earthquake said, in a tone that brooked no dispute, “We shall accept Professor Davidson’s time as the most accurate obtainable for San Francisco.”

  JUST ONE BLOCK SOUTH and eight-tenths of a mile to the west slept the weatherman whose name, still celebrated in meteorological circles (though he had only one mountain named after him), was Alexander George McAdie. A New Yorker, he became a soldier in the Signal Corps after college and made a name for himself by promoting the use of kites rather than balloons for the study of the upper atmosphere (in which signalers were officially interested, since radio waves were affected by what went on there). He became an academic and then joined the government. In 1895, together with his young wife, Mary, he moved out to San Francisco to head the Weather Bureau and to direct the state’s Climate and Crop Service, the latter post carrying with it the title of professor. One of his tasks at the bureau was to record, as accurately as possible, any and all seismic events that happened in and around San Francisco.

  Professor McAdie was an ambitious and a punctilious man, and at the very moment that he was awakened on that dark and chilly April morning, both his ambition and his scrupulous regard for factual observation—as critical in the world of weather as in the study of the stars—came promptly to the fore. As had been his custom ever since he went through the Great Charleston Earthquake of 1886 (“for twenty years I have timed every earthquake I have felt,” he was later to write), the instant he awoke and felt movement he clicked on his flashlight, noted the time on his fob watch, and recorded in his notebook everything that transpired.