British iron industry wood shortage crisis

The driver of the 1558 law and of the eventual switch to coal. The conflict among iron-making, shipbuilding, and glassmaking for limited oak forest. Sets up the transition from charcoal to sea coal to mined coal, which Tom then connects to steam engines and thermodynamics.

What was happening in the 1500s was they had an energy crisis. The energy they were using before was wood. The wood shortage was due to the growing demands of the iron-making industry, according to these folks. The earliest water-powered blast furnace in Europe began operating in Italy in 1463. They found that cannons could be cast from iron instead of bronze. Bronze was expensive — cost comes in again. Their military-industrial complex could make cannons out of cast iron. But to make iron you needed charcoal, and to get charcoal you needed wood. They called it the Weald of Kent — the Weald was where all the mature oaks, beech, and chestnut were, beautiful forest — and they were cutting them down to make charcoal.

So another transportation one, which I kind of like, goes back 400, 500 years, to England. This is a PBS series about metallurgy. It's about twenty hours of lectures on metallurgy. It talks about the first energy crisis in England. The energy crisis in England in the 1500s was they were running out of trees for energy. You would burn wood, you would take the wood, you'd pyrolyze it to make charcoal. How do you make charcoal? Anybody know how to make charcoal? Yes, exactly. You pile up the logs, you cover it with dirt, let a little bit of air in, not much, and you light it underneath the dirt and suffocate it. It burns off all the volatiles, gets all the smoke coming off, and when you're all done, you stop the air going in, put the fire out, let it cool down, take the dirt away, and you've got charcoal. Charcoal is a very clean fuel after you've burned away all the other stuff. But in any case, they were running out of fuel in England.

England's 16th–17th century deforestation forced relocation of iron production to colonial America where trees were available for charcoal. Paired with the Saugus case above.

After you get all the metal out, the next stuff that comes out is the slag. They would block it off, and they'd have another trough over here, because the slag is a molten glass, less dense. They would just form a bunch of slag, and the slag would go to the dump. So there's all kinds of pollution up there by Saugus Ironworks, for ten or fifteen years. If you take another one of my classes I talk about why they came to Saugus to make iron in the 1630s. England was having the energy crisis — they were deforesting, they had cut down all the trees. So what did we have over here? The natural resource: you have limestone and sand all over the world, you have iron ore all over the world. What they had in America in 1620 was trees to make charcoal. It all sort of fits together, it all sort of makes sense historically. This has nothing to do with welding though. Any other questions? It's okay, I like to tell the story.

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