Lin Yuan traveled back and forth between Yongle and modern times - bringing modern strategies back to the Ming Dynasty and letting ancient resources feed back the present. The Qingzhou Iron Course Project was just the starting point. His real battlefield was on the ocean: using the steel filling method to build ships, using modern nautical charts to determine navigation, and allowing the Ming Dynasty fleet to sail around the world. In a modern laboratory, an iron piece from 600 years ago is untying the knot of the photolithography machine.
