Dutch M1815 Musket.

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The "GH" in the centre of the butt stamp stands for sub-inspector Johann Christian Heym of the Delft factory, this stamp says that the stock has been re-newed at Delft in 1840.
The crowned "D" at the brass rest of the pan stands for G.C.Dujardin (see Martens/de Vries, Nederlands Vuurwapens 1813-1866, p. 202 and H.L.Visser, Aspects of Dutch Gunmaking p. 383). Until 1840 the inspector's mark was also struck into the barrels, after this date this was stopped. But it looks as if the D-mark under crown has been struck at the barrel too though very faintly readable. This proofes that the barrel has been really converted from flintlock to percussion
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