Found this on the engineers side of Central KY Railroad #11. Until very recently this side of the locomotive has been completely unaccessable becuase of tons of brush growing up the side of the engine.

A complete mechanical lubricator used to continually grease moving parts and bearings while the locomotive was moving. The actuator arm that leaves the frame goes back to the siderod linkage. It can also be manually operated with the crank shown. The crank still spins freely and the pump has good compression.