Long before phones had read receipts, steamships had already solved the same problem with nothing but brass and chain. 📡 🌊 This is an Engine Order Telegraph. On the bridge, the officer swings the handle to a command like Full Ahead, Stand By or Finished With Engines, and a bell rings beside a matching pointer in the engine room far below. The clever part is the reply. The engineers swing their own handle to match the order, and that motion drives the pointer on the bridge dial to the exact same spot. The captain knows his command was received because the dial in front of him answers back. The whole loop runs on rods, chains and bells, with no electricity anywhere in it. Patented in the 1870s, it has been answering back the same way for more than 150 years. Love Technology? Follow Wealth 🌟 Media: steamship_shieldhall #Engineering #Maritime #Steamship #ShipTech #Technology