Clockwise has dated this piece to the 1880s.
The overhauled movement is of eight day duration mechanism striking the 1/2 hours and hours on a gong with the original lever escapement. The last photo shows the size of this lovely clock compared to a standard carriage clock. The height dimension below is with the handle up and the last photo is of this impressive piece next to a standard carriage clock of the period..

Dumas was an exceptional maker not only of movements but the cases and gong blocks too. The base of the case bears a trademark A D within a diamond, the trademark of clockmaker A. Dumas who worked at 44, Rue Bonaparte in Paris, and probably Saint-Nicolas d’Aliermont. He is known for making carriage clocks with porcelain panels. The Revue Chronométrique, June 1880 p.89, Vol. XI says that Dumas specialises in mignonettes which he makes very well. [see Carriage Clocks, Their History and Development, by Charles Allix and Peter Bonnert]

All my clocks come with my two year guarantee as standard.
Rather than trusting a courier of any sort I unreservedly recommend collection or I can deliver regionally/nationally. All antique clocks require delicate handling and specific setting up so it is far better for a dealer to meet a client and talk them through the process, or set the clock up for them, rather than leave the client struggling at the other end on their own.
Clockwise has dated this piece to the 1880s.
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