What is that thing on the caboose roof?

[ole]

I just got my first no-cupola / flat roof caboose. Okay, so Bachmann forgot/eliminated the smoke stack; the full interior has the stove just like all their cupola cabooses. But what is that bell-shaped / lamp shade thing in the middle of the roof supposed to represent? I'll add a chimney pipe but that 'vent' thing is nothing I ever seen and I am thinking of getting rid of it. Any ideas? Lee in Tucson.

[Dusten Barefoot]

The vent is for either air or the bathroom. I dont see why it would be in the middle of the roof if it is for the bathroom, unless it is for air ventilation. You could move it to the side the toilet is on.
Dusten

[japasha]

On the inside of the roof, right over the stove or closely nearby, the stove pipe fit into a slighly larger pipe that the smoke stack was part of. The idea was to gain  draft for the stove without removing all of the oxygen from the caboose.  It also moved and could expand when the caboose was moving.

[ole]

Since no one has any ideas except for a bath vent, I got rid of this 'center-of-the-car' thing; it was exactly in the center of the caboose (right in the center aisle). I did put in a smoke stack over the stove. As far as a bathroom vent, I have seen a tiny window mounted high in the wall. I am not sure if the window operated or it was just for light in the w.c. But this vent thing is too big to me and in the wrong place, so I will drop it in the parts box for now. Lee