OK OK Guys,
The avatar is of a confederate RR Car used at Petersburg, as Lance so astutely picked up on. It is an O gauge scale train setting on vintage T-rail track. I just started thumbing through my CW artillery book and thought I could make a faximile of this RR car. This is the second of 2 versions I made. The first version had a long barrel with trunnions in the rear (sorta like a mortar with a cannon barrel) that was in a fixed position. The barrel pivoted up and down. The second version and more accurate version is the one you see in the picture. Using the photograph I designed a copy of the train. I used red oak board to build the car and attached 3 sets of 4 wheel trucks to the underside. The opening in the center is a perfect fit for my Brooks Firecracker Cannon. Along the sides I have evenly spaced brass tacks as well as attaching a couple eye hooks with rings hanging from them. This served as decoration and somewhat copied the look of the sides of the train car in the picture. The car has a working coupler on the rear, which I have attached to a train and run around the track.
I have nowhere near the ability of many of you on this forum, but I try to play around when I can.
Thanks for asking.