Sorry I can't find that Ebay auction again, not sure why, checked closed auctions too. Wanted to see if any more info was given. This pic has to be showing Charleston Arsenal, and guessing at date I'd say 1862-4 sometime. The Rebs have had time to make that many nice new Columbiads but haven't yet distributed them. It'd be great if someone did some work on the image and picked out the trunnion markings.