European blast furnace

What it is

A blast furnace fed by water-powered bellows that reaches temperatures high enough to melt iron completely and produce liquid pig iron. It multiplied iron output per unit of labour.

Lapphyttan (Sweden) is dated to 1150–1350; China had already been casting iron since the 5th century BCE, so a possible transmission is debated.

What it led to

• mass production of cast iron for cannons, pots and shot
• an iron industry concentrated in wooded, water-rich regions (Siegerland, Liège, Sweden)
• deforestation and a fuel crisis that would later push the industry towards mineral coal

Built on

• Ironc. 1500 BCE
• Water-powered trip hammer (forge)c. 1100
• Water-powered trip hammer (forge)
• bowl furnace (Stückofen)

Made possible

• Cannonc. 1288
• Cast iron in Europec. 1380
• Coke smelting of iron1709
• Cast iron in Europe
• Cannon

Links

Sources✓ verified 2026-09-23

• https://en.wikipedia.org/wiki/Lapphyttan
• https://www.jernkontoret.se/en/the-steel-industry/the-history-of-swedish-steel-industry/blast-furnace-in-earlier-times/