One of my internet friends sent me a link to a video of a steam engine. Not a locomotive, but a steam-driven water pump. And not just any water pump, but a pump that kept water flowing to a huge chunk of the city of London. The engine that drove the pumps was literally as tall as a three story building, and it still works. A small army of volunteers keeps it in working order and fires it up occasionally for the pleasure of visitors.
To get a steam engine that big going, the engineer uses a much smaller steam engine. Comically small, compared to the big engine. When I first laid eyes on it, I thought, “That’s not such an impressive engine.” And then I realized that the engine was behind it. The starter engine is barely half as tall as the engineer, and it rattles and shakes when he engages it with the flywheel, which is so large it barely appears to be moving at first, but it keeps chugging and the engineer keeps increasing the speed until all the cylinders on the big engine have been rotated through a couple cycles to warm them up and are ready to go on their own.
Even then, they’re just barely ready. When the engineer disengages the starter engine from the flywheel, his body language seems to indicate that he’s not sure the big engine will keep going. He windmills his arms so wildly that I thought he was going to fall over backwards.