Yongle Huaxia: the Erased Global Empire

On the second underground floor of the British Museum, there are eight characters engraved on the bottom of a brass valve: Made in the 17th year of Yongle reign by the Ministry of Industry and Renovation Department. It is a part of a steam engine. But that was the seventeenth year of Yongle - 1419 AD, three hundred years before Watt was born. An orphan product can be a forgery, but a system cannot lie. If the Ming Dynasty really lit up steam, it would never leave just one valve - it should appear at the node of every route around the world. He walked from the warehouse to the archives, from the map to the ruins. As for the period of history he was looking for, someone spent four hundred years digging it out of human memory inch by inch. This is an empire that has been erased. And a guy who got it back.