Is this it?:
The baton of Davout:
No, this is the one from the Musée de l’Armée, Paris.
"... and secondly in the Casan [Kazan] Church [Spb], in which I discovered for the first time the baton of Marshal Davoust, stuck up in a glass-case against one of the piers supporting the dome of the Church. Underneath the baton, upon a gilded metal-plate, are two inscriptions, the one in Russian, the other in Latin, which state that the baton is that of Marshal Davoust, taken near Crasnoe, 5th Nov. 1812; so there can be no doubt of the fact."
"... lastly, the marshal's baton of Davoust (duke of Auerstadt and prince of Eckmuhl), the "Hamburg Robespierre," whose atrocities will be remembered as long as a stone of that city exists under its present name. This trophy, which is kept in a glass case, was taken in the disastrous retreat of 1812; it is said to have been lost in the wild confusion that everywhere prevailed, and was afterward picked up by some straggling Cossack."
"... while the baton of the Maréchal de Davoust is fastened to a pillar opposite the High Altar."
"... le musée de Moscou conserve en effet un bâton attribué au maréchal Davout, perdu par son propriétaire lors de la retraite de Russie."
Bâton de Maréchal (modèle Premier Empire). Reproduction:
Le bâton du Maréchal Davout, Musée de l'Hermitage à Saint-Petersbourg: