I should have mentioned that NPS personnel were kind enough to give me a copy of the "Museum Catalog Record" for the "Eagle" gun. If you want to cite it in a publication, their park acronym at Ft. McHenry is "FOMC."
The catalog number for the item is 2332, and accession number is FOMC-00178. The item was acquired from elsewhere (unspecified) in the National Park system on 6 November 1979.
At some point soon after receipt, it was mounted on a reproduction wooden field carriage and displayed outside the fort walls, were I first saw it. Later it was moved inside to its present more protected location. It appears to have been waxed also (this is a good thing) since the patination is much darker-looking than when it was outside. I didn't ask if any type of cleaning was done, but whatever was done looks to have been in the interest of stabilizing and preserving the piece.
The photo shows the piece as formerly displayed outside, as it appears in the South Bend Replicas catalog. The owner of that company, Paul Barnett, is a friend and I'm sure would not have a problem with my posting his photo here.
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