A stationary engine which drives a pump which stops the sump at the bottom of the mine-shaft from filling up.
I thought this photo would do a good job of catching the colors of the sun on the wood and metal. It came out rather well, but not as well as I thought it would. I wish I could usefully enlarge the bit around where the man is standing, though - the light effects on the back of his legs, the floor, and his immediate surrounds are rather striking.