Abraham Darby smelts iron with coke
At Coalbrookdale in Shropshire, Abraham Darby figured out in 1709 how to use coke — coal baked at high temperature to drive off impurities — to smelt iron in a blast furnace. Charcoal had been the only viable fuel for iron-making for over two thousand years. Coke was abundant; charcoal required ever-shrinking forests. Darby's process let iron production scale with coal mining rather than with woodland regrowth. Within a century, British iron output had risen by a factor of forty, and every machine of the Industrial Revolution — steam engines, rails, ship hulls, factory frames — was built from coke-smelted iron. It is the moment fossil fuels enter heavy industry.
Darby's son and grandson kept improving the process; the family ran Coalbrookdale for nearly a century. The first iron bridge in the world (Iron Bridge, 1779, still standing) was cast from Coalbrookdale iron — a literal monument to coke-smelting and the moment the energy economy shifted from biomass to fossil.
01 · Wood, Water & Land
For most of recorded history, energy meant biomass — wood for heat and smelting, water and wind for milling, animals and humans for muscle. Wealth meant land, because land grew the fuel and fed the workers. The first energy crisis in the Western world was a wood crisis: by the early 1600s, England had cut down so much of its forest for shipbuilding, charcoal, and heating that the kingdom was running short of trees. The cure forced upon them — burning the black rocks dug out of mines for warmth — would, within two centuries, rewrite the global ranking of nations.
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