Update on this device. I had asked about it on FB and this was what someone said, "It’s a fan that can be set on the smokestack of a steam locomotive to pull an induced draft through the fire while it's being warmed up. Once fired up there is a built in blower that can be used for the same purpose, but it requires steam to function. The blower uses a pipe that sends steam jets up the smoke stack which creates a partial vacuum in the smokebox resulting in a draft being pulled through the fire bed. A valve in the cab controls the steam flow. When under way, the exhaust steam from the cylinders being exhausted up the smokestack serves this purpose."
I think that this is pretty cool, and I would imagine that would be something only used on certain older type steam locomotives, or possibly something used in the absence of other such devices that may be slightly more high tech.