An early 19th century 20-bore double-barrelled percussion sporting gun by Joseph Manton, serial number '5896', converted from flintlock, with browned twist barrels, barrel length 76cm, the rib engraved 'Joseph Manton's New Improvements by His Majesty's Patent', gold-lined breeches and tablets, detailed 'Tanner Herzberg', with finely engraved lockplates and steel furniture, dolphin hammers with gold detailing to eyes and teeth, walnut half-stock, the wrist escutcheon bearing crowned lion statant guardant crest, and brass-tipped ramrod, with its green baize-lined mahogany case with accessories and Joseph Manton trade label, and a modern slip case, together with typed research material compiled by the current owner. Provenance: purchased by the current owner from Geoff Walker, 'The Flintlock Collection', who noted prior ownership by Prince Adolphus, 1st Duke of Cambridge, K.G., G.C.B., G.C.M.G., G.C.H., P.C.