And particular, the metal working lathe, which wasn't invented until the 1700s. A proper steam engine that actually performs useful work better than just havi

And particular, the metal working lathe, which wasn't invented until the 1700s. A proper steam engine that actually performs useful work better than just having a dude stand there and move whatever you're trying to move requires very tight tolerances around the cylinders that were previously unobtainable.