I love those things. What a clever idea they are. I can see how these could be used to regulate a valve position to control or limit speed on a steam engine. And I've actually seen a similar gizmo used to operate electrical contacts to regulate the speed of a motor that runs an old adding machine. But it's still an amazing invention. Again, I think the monochrome treatment is good here and I actually like seeing the shadow of the device projected onto the wall behind it.
