Two of them are synchronized! We toured the restored Saugus Iron works. They harnessed the Saugus River to run really impressive equipment to produce wrought iron rod. The wheels powered bellows for the smelting furnace…two pours of 1000 pounds of iron a day and bellows in four reheating furnaces. A huge wheel and really impressive structure ran the “hammer”. A 500 pound drop hammer used to work the raw iron. Oh, the noise! even when it ran about quarter speed for the demo. Finally two synchronized water wheels ran a roller-splitter that thinned then pinch-sheared heavy rod into nail size strips. Unfortunately it doesn’t run any more but still a marvel to see such intricate timing and machinery driven with wooden shafts and gears and powered by water. Here, they claim, we are seeing the birth of the US steel industry. Great stop.