I don't think that's a cupola exactly. Isn't more of a spire? Can someone help us here?
It is a cupola, just an atypically large, non-domed one. Here's a definition:It's a spire. It would have to be rebuilt from photos, drawings, and plans if they're still around.
In architecture, a cupola is a relatively small, most often dome-like, tall structure on top of a building. Often used to provide a lookout or to admit light and air, it usually crowns a larger roof or dome.
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