TAG

# Industrial Revolution

2026-11-06

Time-Traveler's Guide: Why Ancient Swords Took 100 Foldings—And How to Turn Stinky Coal into Metallurgical Coke and Crucible Steel in One Melt

Time-Travel Core Tech Reconstruction Series #10. In the pre-industrial world, cast iron (>2.5% carbon) was too brittle for swords or cannons, while wrought iron (<0.05% carbon) bent on impact. Worse, smelting with raw coal introduced sulfur, causing catastrophic 'hot shortness.' Here is how to build a beehive coking oven and a Huntsman-style kaolin-graphite crucible furnace to pour homogeneous 0.8% high-carbon steel.

2026-11-05

Time-Traveler's Guide: How to Distill 98% Concentrated Sulfuric Acid ('Mother of Industry') from Pharmacy Green Vitriol in a Clay Retort

Time-Travel Core Tech Reconstruction Guide #09. Without sulfuric acid (H₂SO₄), a time traveler cannot make nitric acid, hydrochloric acid, superphosphate fertilizer, lead-acid batteries, or smokeless powder. We break down the thermal decomposition thermodynamics of iron(II) sulfate heptahydrate (FeSO₄·7H₂O), cite Song Yingxing's 1637 Tiangong Kaiwu on 'Green Vitriol (Qingfan)', and provide a step-by-step 650°C glazed stoneware retort distillation guide.