I read somewhere that the most prevalent machine in the world is the electric motor. I thought about that for a while and it made sense. Just look around. But then I began to wonder what the second-most prevalent machine in the world is. Turns out it’s the pump! And most pumps are connected to electric motors of one kind or another, so there you go. Throw a rock and you’ll hit a motor. Or a pump. They’re everywhere.
But that wasn’t always the case, which brings me to a story. Back in the days of gravity-hot-water heating, before we used pumps, a contractor would install big pipes to keep the resistance to flow at a minimum. The boiler would heat the water, which would then flow languidly upward and toward the radiators. It would nudge the colder water that filled the pipes and radiators above the boiler downward, creating a wonderful Ferris wheel of heat. What goes up, shoves what goes down out of the way, and if you’re using gravity, you can rest assured that it will be dependable. Hard to get away from gravity.