The Knowledge: How to Rebuild Our World From Scratch (23 page)

COMMUNICATION

I met a traveler from an antique land

Who said: “Two vast and trunkless legs of stone

Stand in the desert. Near them, on the sand,

Half sunk, a shattered visage lies, whose frown,

And wrinkled lip, and sneer of cold command,

Tell that its sculptor well those passions read

Which yet survive, stamped on these lifeless things,

The hand that mocked them and the heart that fed:

And on the pedestal these words appear:

‘My name is Ozymandias, king of kings:

Look on my works, ye Mighty, and despair!’

Nothing beside remains. Round the decay

Of that colossal wreck, boundless and bare,

The lone and level sands stretch far away.”

P
ERCY
B
YSSHE
S
HELLEY,
“Ozymandias” (1818)

TODAY, WITH THE INTERNET,
ubiquitous wireless networks, and handheld smartphones, communication with one another anywhere in the world is effortless and instantaneous. We keep in touch via e-mail and Twitter, websites disseminate news and information, and we can access the wealth of human knowledge from the palm of our hand. But in a post-apocalyptic world you’ll need to return to more traditional communication technologies.

Before the invention of writing, knowledge circulated among the minds of the living, conveyed only by the spoken word. Yet there is only so much data that can be stored in oral history, and the danger is that when people die ideas are lost forever. But once committed to a physical medium, thoughts can be stored faithfully, referred back to years later, and built up over time. A culture that has developed writing can accumulate far more knowledge than could ever be cached in the collective memories of its populace.

Writing is one of the fundamental enabling technologies of civilization. It involves the conceptual leap of transforming spoken words into sequences of drawn shapes: either arbitrary letters representing the individual sounds of the language (such as the phonemes of English) or characters symbolizing particular objects or concepts (like the morphemes of Chinese). At the basic level, it allows you to permanently record the agreed terms of trade, a land lease, or a code of laws. But it is the accumulation of
knowledge
that allows a society to grow culturally, scientifically, and technologically.

In the modern world we’ve come to take for granted such staples of civilization as pen and paper, and realize how vital they are only when we can’t simply reach for the back of an envelope to jot down a shopping list, or when we bemoan the confounding disappearance of the ballpoint we put down only two minutes ago. While plentiful paper will be left behind by our civilization, it is a particularly perishable material and will readily burn with the wildfires tearing through deserted cities or molder away with humidity and floods. How can you easily mass-produce paper for yourself, and leapfrog over the time-consuming production of other materials, such as papyrus and parchment, used historically?

Paper was invented by the Chinese sometime around 100 AD,
although it took more than a millennium to diffuse across to Europe. Paper made from tree pulp, though, is a surprisingly modern innovation. Until the late nineteenth century, paper was mainly manufactured from linen fragments, recycling tattered rags. Linen is a fabric made from fibers of the flax plant (see Chapter 4), and any fibrous plants can in principle be converted into paper: hemp, nettles, rushes or other coarse grasses. But as demand grew, spurred on, as we’ll see, by the plethora of books and newspapers churned out of the printing presses, other suitable fibers were intently sought. Wood is a fabulous source of good-quality papermaking fibers, but how do you disassemble a thick, solid tree trunk into a fine soupy mush of soft, short strands without breaking your back in the process?

The fibers that make paper so light yet strong are composed of cellulose. Chemically this is a long-chain compound used by all plants as the main structural molecule between their cells, and in particular in their stem and side shoots; it is the pithy strands of cellulose that get stuck between your teeth when you munch on celery. In the stout trunks of trees and shrubs, however, the cellulose fibers are reinforced with another structural molecule called lignin, which locks the cellulose strands together to make wood. This provides the tree with the ideal structural material for a strong, load-bearing central column and wide-spreading branches to splay its leaves out before the Sun, but it makes the cellulose fibers lamentably inaccessible to us.

Traditionally, plant fibers were separated by crushing the stems and then retting—soaking them for several weeks in stagnant water to allow microorganisms to begin decomposing the structure—and then violently pounding the softened stalks to liberate the cellulose fibers by brute force. The good news is that you can save yourself a great deal of time and effort and leapfrog straight to a much more effective scheme.

The links that bind together cellulose and lignin in trees are vulnerable to the chemical severing process known as hydrolysis. This is the same molecular operation that is employed in saponification during
soap making, and we achieve it with exactly the same means: by rallying alkalis to the cause. The best parts of the tree or plant to use are the stem or trunk and branches—the roots and leaves don’t contain much of the cellulose fiber required. Chop the material into small pieces to expose as much surface area to the action of the solution as possible, then bathe it in a vat of boiling alkaline solution for several hours. This breaks the chemical bonds holding together the polymers, causing the plant structure to soften and fall apart. The caustic solution attacks both cellulose and lignin, but the hydrolysis of lignin is faster, allowing you to liberate the precious
papermaking fibers without damage while the lignin degrades and dissolves. Short white fibers of cellulose will float to the top of the murky brown, lignin-stained broth.

Any of the alkalis we covered in Chapter 5—potash, soda, lime—work, though the preferred option through much of history has been to use slaked lime (calcium hydroxide), as it can be generated in bulk by cooking limestone, while potash is fairly labor-intensive to produce by soaking timber ashes. But once you’ve cracked the artificial synthesis of soda (we’ll come to this in Chapter 11), the best option by far for chemical pulping is to use caustic soda (sodium hydroxide), which powerfully promotes hydrolysis. You generate this directly in the pulping vat by mixing together slaked lime and soda.

Collect the recovered cellulose fibers in a sieve and then rinse several times until they run clear of the mucky lignin color. To lighten the shade of the finished paper to a clean white, you can also soak the pulp in bleach at this point. Calcium hypochlorite or sodium hypochlorite are both effective bleaching agents, and can be created by reacting chlorine gas (produced
electrolytically from seawater
) with slaked lime or caustic soda, respectively. The chemistry behind this bleaching effect is oxidation: bonds in the colored compounds are broken to destroy the molecule or convert it to an uncolored form. Bleaching is critical not only to papermaking, but also to textile
production, so it will likely be a key driving force for expanding the chemical industry during a reboot.

Pour a dollop of this sloppy cellulose soup across a fine wire mesh or cloth screen, bounded on the sides by a frame, so that the fibers form a higgledly-piggledy mat as the water drains out. You then press it to squeeze out the remaining water and to ensure flat, smooth sheets of paper, and leave to dry.

You’ll find small-scale paper production much easier if you’re able to scavenge a few items from the fallen civilization. A wood chipper or even a large food processor, powered from a generator, will make lighter work of the chewing up of plant matter into a thick vegetative soup: but you can also let windmills or watermills provide the mechanical brawn needed for driving trip-hammers to pound the material.

However, creating clean, smooth paper is only half of the solution to being able to use writing for communication and recording permanent stores of knowledge. The other critical task, once all of the remnant ballpoints have dried up or disappeared, is to make your own reliable ink with which to form the written word.

In principle, anything that irritatingly stains your cotton shirt if you accidentally splash yourself can also be used as a makeshift ink. You can take a handful of intensely colored ripe berries, for example, and crush them to release their juice, strain to remove the mashed fruit pulp, and dissolve in some salt to serve as a preservative. The major problem with most plant extract inks, though, is their impermanence. To preserve your words and the recovering society’s newly accumulated knowledge indefinitely, you really want an ink that won’t readily wash off the page or fade in sunlight. The solution that emerged in medieval Europe is known as iron gall ink. In fact, the history of Western civilization itself was written in iron gall ink. Leonardo da Vinci wrote his notebooks with it. Bach composed his concertos and suites with it. Van Gogh and Rembrandt sketched with it. The Constitution of the United
States of America was committed to posterity with it. And a formulation very similar to the original
iron gall ink is still in widespread use in Britain today: registrar’s ink, required to be used for legal documents such as birth, death, and marriage certificates, uses exactly the same medieval chemistry.

As the name reveals, the recipe for iron gall ink contains two main ingredients: an iron compound and an extract from plant galls. Galls appear on the branches of trees such as oak, and are formed when parasitic wasps lay their eggs in the leaf bud and irritate the tree into forming a growth around it. They are rich in gallic and tannic acids, which react with iron sulfate—created by dissolving iron in sulfuric acid. Iron gall ink is practically colorless when first mixed, and so it’s difficult to see where you’re writing unless another plant dye is also included. But with exposure to the air, the iron component oxidizes to turn the dry ink a deep, enduring black.

A rudimentary pen can also be made in the time-honored fashion. Soak a bird’s feather (goose or duck was preferred historically) in hot water and pull out the material within the shaft. Bring the tip into a sharp point by cutting into each side, and then undercut the bottom face into a gentle curve to create the classic shape of a writing nib. Slitting backward slightly into the pointed tip will allow the nib to hold a tiny reservoir of ink as you write, between replenishing dunks into the inkwell.

If writing is the critical development to enable the permanent storage and accumulation of ideas, then the printing press is the machine for the rapid replication and extensive dispersal of human thought. Today, the developed world boasts near-universal literacy, and an estimated
45 trillion pages are printed every day: books, newspapers, magazines, and pamphlets.

Without printing, if you wanted a document reproduced it would take a dedicated team of scribes arduously copying it by hand for weeks. Hence only the powerful and well resourced would be able to afford the project, which also means only approved or endorsed texts are propagated. But with the dissolution of such a choke point, thanks to the printing press, knowledge becomes democratized. Not only does learning become available to everyone in society, but anyone can rapidly disseminate their own ideas, from new scientific theories to radical political ideologies, encouraging debate and promoting change.

The basic principle of printing is that a page of writing is re-created as rows of types—cuboidal blocks, each with a letter embossed on the top face—arranged within a rectangular frame. The type is inked and then pressed onto a sheet. Once the frame has been typeset, the same page of text can be replicated again and again exceedingly quickly, and when done, the letters are simply rearranged into another page of text. Even a rudimentary printing press can reproduce a document hundreds of times faster than a scribe.

There are three major challenges that you’ll need to solve for a post-apocalyptic resurrection of the movable-type printing press, which Johannes Gutenberg invented in fifteenth-century Germany.
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You’ll need to find a way to easily produce large numbers of precisely
sized types. You’ll also need to devise a mechanism to provide an even but firm pressure to apply the print to the page. And third, you’ll need to invent a new kind of ink that doesn’t flow freely from a pen nib, but sticks well to intricate metallic detail.

The first issue you’re faced with is what material you use to make the types. Wood can be carved easily, but this would necessitate the diligent work of a skilled craftsman to hand-make each and every piece of type individually—around eighty letters (both lowercase and capitals), numbers, punctuation marks, and other common symbols—and then produce multiple, identical copies of each. And all that hard work for just a single set of type, in only one font size and one style.

So in order to mass-produce printed books, you must first mass-produce the tools for printing. This can be achieved by type casting: founding identical letter blocks with molten metal. The solution for creating types with straight, smooth sides and perfect right-angle edges that slot perfectly alongside each other in rows, Gutenberg realized, is to cast the types in a metal mold with a sharp cuboidal interior void. Cleverly, the crisp shape of a particular letter can be formed on the end face of the block by positioning a swappable matrix at the bottom of the mold. These matrices can be made from a soft metal such as copper, and the precise indent of a letter hammered into each of them very simply with a hard steel punch. Now all you have to do is engrave each letter, number, or symbol just once onto different punches, and you can effortlessly churn out countless pieces of identical type.

There is one final problem, though, thrown up by the nature of the letters in Western script, which is the large variability in their girth: the svelte “i” or slender “l,” compared with the rotund “O” or broad-shouldered “W.” To be read easily the letters should huddle closely together without gaping spaces around the skinnier letters and numbers. The upshot is that you need to be able to cast cuboidal types that are all exactly the same height, so that they print uniformly on the page, but each with a different width.

The solution is the final spark of Gutenberg’s inspiration in devising an elegant system for mass-producing the building blocks of printing. Create the mold in mirror-image halves: two L-shaped parts facing each other to create a cuboid space between them. The walls of this cavity can be simply slid toward or away from each other to smoothly adjust the width of the mold, without changing the depth or height (try it with your thumbs and index fingers now to see how this ingenious system works). Casting a perfectly formed type is now as simple as placing the relevant stamped matrix at the bottom of the mold, setting the width, pouring in the molten metal, and then ejecting the finished piece when it has set by parting the L-shaped halves again.

MOLD FOR TYPE CASTING. THE MATRIX, BEARING THE IMPRINT OF THE LETTER STAMPED INTO IT, LIES AT THE BOTTOM OF THE CENTRAL CAVITY.

After a page of text is typeset, the type face is inked and transferred as an intricately detailed impression onto a blank sheet. There are a range of mechanical devices that enable the application of enhanced force, such as the simple lever or a pulley system, and both have been used throughout history for squeezing out excess moisture in paper production. Gutenberg grew up in a wine-growing region of Germany, and so co-opted another ancient device for his groundbreaking invention. The screw press is a Roman technology dating back to the first century AD, used extensively for juicing grapes or extracting oil from olives. It also provides the ideal compact mechanism for applying a firm but even pressure onto two plates, squeezing the inked type onto the page. This key component of printing survives to this day in our collective name for the newspapers, and by extension the journalists who report for them: “the press.”
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The availability of paper is not a prerequisite for the printing press, as the technique also works on parchment made from calfskin (but not on brittle papyrus sheets). But without mass-produced paper, printed books could never be produced cheaply enough for the general population, and so their social-revolutionary potential would remain unrealized. If the book you hold in your hands now had been published in the same typographic format as Gutenberg’s first Bible on parchment pages, each copy would require the complete hides of around 48 calves.

Successful printing does rely on a suitable ink, however. The free-flowing water-based inks developed for handwriting, like iron gall ink,
are totally inappropriate for printing. To print crisp lettering you need a viscous ink that will stick readily to the metal features of the detailed type and then transfer cleanly to the paper without smearing, running, or blurring. Gutenberg solved this particular challenge by borrowing from a fashion that was only just starting among Renaissance artists: the use of oil paints.

Both the ancient Egyptians and the Chinese developed a black ink based on soot at around the same time, roughly four and a half thousand years ago. The soot’s tiny carbon particles serve as a perfectly dark pigment when mixed with water and a thickener, such as tree gum or gelatin (animal glue—see Chapter 5). This is the composition of India ink, which, despite its name, was actually first developed in China and traded with India, and is still popular with artists today. Indeed, a suspension of carbon-black pigment particles also forms the basis of photocopier and laser-printer toner. Soot particles can be trapped from the smoky flame of burning oils—a substance known as lampblack—as well as by charring organic materials such as wood, bone, or tar.

While carbon-black pigments have a long heritage, the glue- or gum-thickened India ink is not suitable for a printing press: you need an ink with very different viscosity (runniness) and drying behavior. And this is where Gutenberg borrowed from the very beginnings of Renaissance oil painting. Lampblack mixed into linseed or walnut oil dries well and sticks to metal type far better than a runny, water-based ink. (Linseed oil does need to be processed before being used, though: boil it and remove the thick, gluey mucilage that separates on top.) You can control the ink’s crucial viscosity with two other ingredients, turpentine and resin. Turpentine is a solvent used for thinning oil-based paints, and is produced by distillation of resin tapped from pines or other conifer trees (see
here
). The hard, solidified resin left behind after the volatile compounds have been driven off during distillation, on the other hand, will thicken the solution. By tweaking the balance of these two contrary constituents you can perfect the viscosity of the
ink, and you can control its drying behavior by varying the proportion of walnut and linseed oils.

So printing can rapidly replicate knowledge through your recovering civilization, and long-distance communication can be achieved by sending written messages. But how might you use electricity to communicate over great ranges without having to go through all the bother of physically transporting the message?