Most visitors online was 1990 , on 7 Feb 2022
I didn't know that a duke is three acanthuis leaves, it seems. I still think it's worth hunting for a French marquis whose name begins with "H"."marquis (marquis): a coronet of alternating acanthus leaves and groups of three pearls in trefoil (or two pearls side by side in some versions)."
It's difficult to know, given my lack of knowledge of the traditions and usage of French heraldry ... but if these were English crests then definitel not! A letter surmounted by a crown would only indicate the holder of the rank, so the "H" would definitely be the marquis who owned the coat of arms.The 'H' might be for Horloger or Horlogerie.