The Knowledge: How to Rebuild Our World From Scratch (40 page)

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Contrary to popular belief, a bicycle’s stability has little to do with the gyroscopic effect of its spinning wheels, especially at slow speeds.

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Ironically, about 100 miles is still the maximum range for modern electric cars: technological improvements in battery storage and electric motors have been perfectly offset by an increase in car size and weight, and drivers of electric vehicles suffer from “charge anxiety.”

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So why was it that the Chinese developed paper a good millennium before it became common in Europe, and also published texts using wooden block printing, but never made the step to movable-type printing taken by Gutenberg? The historical reasons probably come down to a fundamental difference between the nature of European writing and Eastern scripts. Western writing is made up of a small set of letters rearranged into combinations to spell out the sounds of different words, whereas written Chinese is composed of a vastly greater number of complex compound characters, each symbolizing a particular object or concept. The simple rearrangement of Western letters lends itself to movable-type printing.

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If you anticipate that you’ll want to run further impressions of the same body of text in the future, such as for subsequent print runs of an important treatise, you can save yourself the hassle of having to typeset thousands of individual letters all over again by saving the page configuration. The types themselves are too valuable to be left arranged in the frame, but you can take an impression of the text layout in plaster and then use this as a mold for casting a metal plate of the whole page. This is the original meaning of the word “stereotype.” The nickname for a stereotype plate is “cliché,” apparently after the sound made during the casting—and so to use a cliché is to rehash a block of commonly printed text.

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Modern electronics have moved beyond power-hungry vacuum tubes, and now exploit the domain of properties of semiconductor materials: vaccum-tube rectifiers are replaced by solid-state diodes, and the voltage-controllable behavior of the triode is reproduced by the silicon transistor. The monolith to miniaturization that is the smartphone in my pocket contains
trillions
of transistors, each of them functionally identical to a warmly glowing vacuum tube.

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In the second half of the nineteenth century, the French emperor Napoleon III hosted a banquet with aluminum cutlery to impress his most distinguished dinner guests, laying out the aluminumware rather than silverware. Bizarrely, it was simultaneously the most common and the most precious metal on the planet. But with the development of a suitable flux and the use of electrolysis for mass production, aluminum slumped from the prestige of royal dinner sets to the indignity of drink cans discarded by the millions.

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Indeed, since the 1930s we’ve been going one step further, and filling additional rows at the bottom of the periodic table with elements that do not exist naturally, but were technologically created—atoms with a nucleus so swollen with protons and neutrons that they are acutely unstable and disintegrate again almost immediately in a flurry of radioactivity. Through our own history, therefore, we have not only cooked up new materials—ceramics like glass or metallic mixtures such as steel alloys—or novel molecules like the organic polymers of plastics, but learned how to transmute elements themselves, achieving the dream of the alchemists. And with dedication, a civilization following in our footsteps would be able to accomplish the same.

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You can also use a camera to demonstrate the existence of a prior, technologically advanced civilization on Earth even far into the future. A photo taken of the night sky toward the celestial equator (90 degrees from the pole, see Chapter 12) with an exposure of a minute or two will smudge all the stars into curved streaks with the Earth’s spin. But occasionally you’ll also spot something very curious: pinpoints of light that haven’t been smeared at all. These objects apparently fixed in the sky must just so happen to be moving at exactly the same rate that the planet turns—artificial things that were deliberately placed around the Earth in this particular configuration. These are the geostationary satellites ringing the equator at a special distance where the orbital period is exactly one day; such satellites remain fixed above the same point on the Earth’s surface and so make good communications relays. Their orbit is also exceedingly stable, and long after all of our cities and other artifacts have crumbled to dust and been buried, they will remain monuments to our technological civilization in the pristine environment of space, easy to spot if you know how.

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While we’re on silver chemistry, it’s worth mentioning another crucial capability: that of creating a mirror, indispensable beyond mere vanity as a critical component of high-powered telescopes or the sextant for navigation. Mix alkaline ammonia solution (see Chapter 5) with silver nitrate and a little sugar, and then pour it over the back of a clean piece of glass. The sugar reduces the silver back to pure metal and so deposits a thin shiny layer directly onto the glass surface.

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In modern nomenclature, we would say that common sea salt (sodium chloride) and soda ash (sodium carbonate) are both chemical salts of the same base (sodium hydroxide, known traditionally as caustic soda).

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In the early nineteenth century these were simply dumped as toxic waste: insoluble heaps of dark ashy calcium sulfide were piled up in the fields surrounding the soda works, and clouds of hydrogen chloride poured out of tall chimneys, causing great damage to surrounding plant life. In 1863 Britain passed the Alkali Act, which prohibited the venting of hydrogen chloride—the first modern legislation against air pollution. The immediate response of the soda plants was to scrub this soluble gas by sprinkling water down the inside of their chimneys and discharge the resultant hydrochloric acid straight into the nearest river, deftly sidestepping the legislation by turning air pollution into water pollution!

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More than two tons of ammonium nitrate fertilizer were packed by Timothy McVeigh into the back of a truck for the Oklahoma City bombing, and one of the world’s largest non-nuclear explosions occurred in 1947 when a fire caused a ship carrying more than 2,000 tons of the compound to detonate in the port of Texas City.

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The parallel streets of Manhattan’s grid-like layout are aligned along a bearing of 30 degrees east of celestial north, and twice a year (in late May and mid-July, evenly flanking the summer solstice), this grid behaves like a city-size Stonehenge, with the sun setting right down the centerline of the canyon-like streets.

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If you need convincing, you can demonstrate that the tracking of the Sun across the sky and the wheeling of the nighttime canopy of stars is caused by our motion, not theirs. Dangle a heavy bob from a long piece of string, indoors and away from any gusts of wind, and carefully set it swinging, straight back and forth without any sideways sway. The swing of “Foucault’s pendulum” will seem to rotate around the ground over the course of a day. But the pendulum is suspended in open air, and so there can be no force acting to cause it to twist; in fact, the pendulum is swinging in the same direction all along as the Earth itself turns underneath.

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These first appeared in late-thirteenth-century monasteries, their chimes calling the monks to prayer. In fact, the crucial mechanisms predate the adoption of clock faces and hands by more than a century (and the minute hand didn’t appear for another three hundred years): the earliest clocks couldn’t display the time but were ingenious automated systems for ringing bells (indeed, the name derives from the Celtic for bell).

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All clocks are in essence devices for counting the oscillations of some regular process and displaying the tally. Modern clocks are no different in principle, they just exploit different physical phenomena with more rapid and more precisely regular ticks: counting the electronic oscillations of a quartz crystal in a digital watch or the microwave oscillations of a cloud of cesium in an atomic clock.

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Although the day will actually be slightly longer because the sunlight is deflected in the Earth’s atmosphere to give a period of twilight in the morning and evening.

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How can you prove it is the Earth that moves around the Sun, and not vice versa (and thus that we are not in a privileged location in the center of the solar system)? All you need is a suitably accurate clock. Over a few nights you’ll notice that any given star rises almost exactly four minutes later each night. If the only motion involved were the Earth turning on its axis like a top, the stars would wheel into view at exactly the same moment every night. But in fact the Earth’s position shifts slightly, and so it takes a short while for its rotation to bring the same view as last night back into sight. Four minutes is
¹
/
₃₆₅
of 24 hours: the Earth has moved forward one day in its yearlong circuit of the sun.

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In fact, you’ll notice from your records kept over the first few decades of the reboot that with a 365-day calendar the date of the stellar events drifts steadily later in the year. This tells you that the year length isn’t actually 365 days on the nose, but a fraction longer. (Thinking about it, there’s no reason to expect the planet’s orbit around the Sun to be an exact multiple of the time it takes to spin on its own axis.) Over 1,460 years a marker will slide backward through the whole year to arrive back on the original day you observed it. So relative to the celestial backdrop, the Earth spins an extra 365 days over 1,460 years. Thus there is an additional quarter day in each year that you need to take account of; otherwise your calendar will slip embarrassingly out of sync with the seasons. This is why in 46 BC Julius Caesar decreed the realignment of the date and introduced the leap year to ensure the calendar remain in step with the Earth.

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Large surveying ships would often carry several chronometers, to average out errors and for multiple redundancy. HMS
Beagle
set out in 1831 with no fewer than 22 chronometers to ensure an accurate fix on the location of foreign lands (including the Galápagos Islands, where Darwin’s observations of the wildlife set him toward his revolutionary theory).

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I’m sure that many people reading this book have been surprised that a particular topic they consider important has been overlooked. As far as possible within the bounds of a single book, I’ve tried to include as much as I think would be absolutely indispensable knowledge for rebooting. You could rebuild a functioning technological civilization without knowledge of human evolution or the planets of the solar system, but not without being able to effectively maintain the fertility of your fields or produce chemical alkalis. I’d be keen to hear from you via this book’s website, the-knowledge.org, as to what you personally would consider vital knowledge for accelerating the rebuilding of civilization from scratch, and why.

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About the only countries that haven’t fully adopted this system are the US and the UK, where outdated units persist with the use of miles on road signs and car speedometers and drinks served in restaurants and pubs by the pint. The historical reason was Napoleon excluding the English-speaking world when he convened a congress in 1798 to encourage international adoption of the new metric system—the British had just sunk the French fleet at the Battle of Aboukir and so were not invited to the party.

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In fact, historically, the argument ran the other way, and it was proposed in the seventeenth century to define the meter as the length of a pendulum that has a half-period of exactly one second. This is why the word “meter” shares its meaning with the rhythm of poetry or music. The proposal was abandoned in favor of an alternative based on the dimensions of the Earth, however, due to the effect that variations in the local gravitational strength across the face of the planet have on a pendulum’s rhythm.

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In actual fact, since the process of boiling depends on other factors such as the roughness of the container for forming bubbles, the temperature of a saturated cloud of steam at atmospheric pressure is a more consistent and reliable standard.

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Mathematics is one topic that has not been covered in depth here. Calculations are clearly important for engineering designs, and mathematics is the language for the statement of physical law, but it does not lend itself to explanations of general principles within the scope of this book.

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Similar, small-scale scenarios have occurred in recent history: with the fall of the Soviet Union in 1991, the small republic of Moldova experienced a crippling crash in its economy, forcing people to become self-sufficient, readopting museum-exhibit technology such as spinning wheels, hand looms, and butter churns.

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If you ignore the remnant material that will be left behind by the collapse of our society, this thought experiment on aiding the recovery of post-apocalyptic survivors could also provide the manual you’d need to develop a technological civilization from scratch after accidentally falling through a time warp into the Paleolithic era ten thousand years in the past, or crash-landing a spaceship on an uninhabited but clement Earth-like planet. This is the ultimate Robinson Crusoe or Swiss Family Robinson shipwreck fantasy—not washing up on a small deserted island, but starting again on a whole empty world.

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While the most discernible features of a society may be its grand monuments, or art, music, or other cultural output, the basics supporting civilization are fundamentals such as agricultural productivity, sewage treatment, and chemical synthesis. This book will focus on the critical science and technology as they are universal: a particular physical law is true no matter where (or when) you are, and a society even thousands of years in the future will have the same basic needs that can be alleviated by technology—food, clothes, power, transport, and so on. Art, literature, and music are an important part of our cultural heritage, but the recovery of civilization wouldn’t be held back half a millennium without them, and the post-apocalyptic survivors will develop their own expressions that hold relevance to them.