Have you looked into the Jules Verne novels. He had some spectacular vehicles in his stories (27 thousand leagues under the sea, around the world in 80 days, etc.) and this strikes me as something down that road. Also, the clasp looks to be rather old as it does not have a safety clasp on it, however, looks can be deceiving.
Sorry, I may have confused you more, rather than helping, but...
Carolyn