The Knowledge: How to Rebuild our World from Scratch is a new book
out in the U.S. now, and a New York Times science bestseller. If civilization
does collapse, whether it’s caused by a viral pandemic, coronal mass ejection,
or financial meltdown, the break in normal services is likely to cause a great
deal of panic and perhaps a severe depopulation among the unprepared. The world
as we know it has ended, but what now? What can the survivors do to ensure they
thrive in the long-term, and how can you begin rebuilding a proficient society
over the generations? Many preppers keep a large stockpile of preserved food,
defensive weapons and ammunition, and other consumables, but this won’t last
forever. What do you do when it starts running out? How do you teach your
children to make for themselves all that they need and their children will
need?
The
essence of The Knowledge is a thought experiment– an exploration of the
behind-the-scenes fundamentals of society. What is the crucial science and
technology behind how our modern world works and how did civilization progress
over the centuries? And if you ever had to, how could you avoid another Dark
Ages and reboot civilization as rapidly as possible? What could you do better
the second time around?
The
Knowledge
takes the discussion beyond many prepper books and websites that explain
important topics, like survival skills, preserving food, and weapons (such as
How to Survive TEOTWAWKI) and explains all you need to know in areas like
agriculture, materials, energy, and transport in order to rebuild society
itself, at least as far as is possible within a single book.
Below
is an excerpt of the book, exclusive to SurvivalBlog, from the section dealing
with creating crucial substances for yourself.
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Substances
Even
before humanity began to settle down and the first cities were founded in
Mesopotamia, our lives depended on the deliberate extraction, manipulation, and
exploitation of natural chemicals. Over the centuries we’ve learned new ways to
interconvert between different substances, transforming those that can be most
easily acquired from our surroundings into those that we need the most, and
producing the raw materials with which our civilization has been built. Our
success as a species has come not just from mastering farming and animal
husbandry or employing tools and mechanical systems to ease labor; it also
derives from the proficiency with which we can provide substances and materials
with desirable qualities.
The
first substance that a recovering post-apocalyptic society will need to begin
mining and processing for itself, because of its multitude of functions that
are absolutely critical to the fundamental operations of any civilization, is
calcium carbonate. This simple compound, and the derivatives easily produced
from it, can be used to revive agricultural productivity, maintain hygiene and
purify drinking water, smelt metals, and make glass. It also offers a crucial
construction material for rebuilding and provides key reagents for rebooting
the chemical industry.
Coral
and seashells are both very pure sources of calcium carbonate, as is chalk. In
fact, chalk is also a biological rock: the white cliffs of Dover are
essentially a 100-meter-thick slab of compacted seashells from an ancient
seafloor. But the most widespread source of calcium carbonate is limestone.
Luckily, limestone is relatively soft and can be broken out of a quarry face
without too much trouble, using hammers, chisels, and pickaxes. Alternatively,
the scavenged steel axle from a motor vehicle can be forged into a pointed end
and used as a drill to repeatedly drop or pound into the rock face to create
rows of holes. Ram these with wooden plugs and then keep them wet so that they
swell and eventually fissure the rock. But pretty soon you’ll want to reinvent
explosives (Chapter 11) and use blasting charges to replace this backbreaking
labor.
Calcium
carbonate itself is routinely used as “agricultural lime” to condition fields
and maximize their crop productivity. It is well worth sprinkling crushed chalk
or limestone on acidic soil to push the pH back toward neutral. Acidic soil
decreases the availability of the crucial plant nutrients we discussed in
Chapter 3, particularly phosphorus, and begins starving your crops. Liming
fields helps enhance the effectiveness of any muck or chemical fertilizers you
spread.
It
is the chemical transformations that limestone undergoes when you heat it,
however, that are particularly useful for a great range of civilization’s
needs. If calcium carbonate is roasted in a sufficiently hot oven—a kiln
burning at least at 900°C—the mineral decomposes to calcium oxide, liberating
carbon dioxide gas. Calcium oxide is commonly known as burned lime, or
quicklime. Quicklime is an extremely caustic substance, and is used in mass
graves—which may well be necessary after the apocalypse—to help prevent the
spread of diseases and to control odor. Another versatile substance is created
by carefully reacting this burned lime with water. The name quicklime comes
from the Old English, meaning “animated” or “lively,” as burned lime can react
so vigorously with water, releasing boiling heat, that it seems to be alive.
Chemically speaking, the extremely caustic calcium oxide is tearing the
molecules of water in half to make calcium hydroxide, also called hydrated lime
or slaked lime.
Hydrated
lime is strongly alkaline and caustic, and has plenty of uses. If you want a
clean white coating for keeping buildings cool in hot climes, mix slaked lime
with chalk to make a whitewash. Slaked lime can also be used to process
wastewater, helping bind tiny suspended particles together into sediment,
leaving clear water, ready for further treatment. It’s also a critical
ingredient for construction, as we’ll see in the next chapter. It’s fair to say
that without slaked lime, we simply wouldn’t have towns and cities as we
recognize them. But first, how do you actually transform rock into quicklime?
Modern
lime works use rotating steel drums with oil-fired heating jets to bake
quicklime, but in the post-apocalyptic world you’ll be limited to more
rudimentary methods. If you’re really pulling yourself up by your bootstraps,
you can roast limestone in the center of a large wood fire in a pit, crush and
slake the small batches of lime produced, and use them to make a mortar
suitable for building a more effective brick-lined kiln for producing lime more
efficiently.
The
best low-tech option for burning lime is the mixed-feed shaft kiln: essentially
a tall chimney stuffed with alternating layers of fuel and limestone to be
calcined. These are often built into the side of a steep hill for both
structural support and added insulation. As the charge of limestone settles
down through the shaft, it is first preheated and dried by the rising draft of
hot air, then calcined in the combustion zone before it cools at the bottom,
and the crumbling quicklime can be raked out through access ports. As the fuel
burns down to ash and the quicklime spills out the bottom, you can pile in more
layers of fuel and limestone at the top to keep the kiln going indefinitely.
A
shallow pool of water is needed for slaking the quicklime, and you could use a
salvaged bathtub. The fine particles produced will turn the water milky before gradually
settling to the bottom and agglutinating as the mass absorbs more and more
water. If you drain off the limewater, you’ll be left with a viscous sludge of
slaked-lime putty. Limewater is used to produce gunpowder, and the slaked lime
is a critical ingredient for construction: making a mineral glue for sticking
together fired-clay bricks or gravel for concrete, as we’ll see in the next
chapter. Another fundamental use of lime is for making soap.
Soap
can be made easily from basic stuff in the natural world around you and will be
an essential substance in the aftermath for averting a resurgence of
preventable diseases. Health education studies in the developing world have
found that nearly half of all gastrointestinal and respiratory infections can be
avoided simply by regularly washing your hands.
Oils
and fats are the raw material of all soaps. So, somewhat ironically, if you
carelessly splash bacon fat onto your shirt cooking breakfast, the very
substance you use to clean it out again can itself be derived from lard. The
key step in making soap is to chemically break open, or “hydrolyze” the fatty
molecules, and for this you need a potent alkali. Alkalis are the opposites of
acids, and when the two meet they neutralize each other to produce water and a
salt. Coated with a fur of these long soap molecules, a small droplet of oil is
stabilized in the midst of the water that rejects it, and so grease can be
lifted off skin or fabric and be washed away. The bottle of “invigorating,
reviving, hydrating, deep clean sea splash” men’s shower gel in my bathroom
lists nearly thirty ingredients. But alongside all the foaming agents,
stabilizers, preservatives, gelling and thickening agents, perfumes, and
colorants, the active ingredient is still a soap-like mild surfactant based on
coconut, olive, palm, or castor oil.
The
pressing question, therefore, is where to get alkali in a post-apocalyptic
world without reagent suppliers. The good news is that survivors can revert to
ancient chemical extraction techniques and the most unlikely-seeming source:
ash.
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Dr.
Lewis Dartnell
is a research fellow at the University of Leicester, England, and the author of
The Knowledge: How to Rebuild our World from Scratch, out now with
Penguin Press. Explore extra material on the book’s website: www.the-knowledge.org
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