Here is the Holts listing for Lot 908: Notice the section talking about traces of a ring bulge. I have an E-mail from Holts concerning the bulge. I would never bid on anything without asking a few questions.
FORMERLY THE PROPERTY OF H.H. THE MAHARAJ OF DHOLPUR
ALEX.r HENRY
A FINE .360 BLACK POWDER EXPRESS HENRY PATENT BACK-ACTION SIDELOCK NON-EJECTOR DOUBLE RIFLE, serial no. 6546,
26in. fine black powder only damascus barrels with raised matt rib, central section engraved 'ALEX.R HENRY. EDINBURGH AND LONDON. MAKER TO THEIR ROYAL HIGHNESSES THE PRINCE OF WALES AND DUKE OF EDINBURGH', open sights with ivorine insert and folding leaf sight with silver inlay, bead foresight with flip-up moonsight, Henry patent rifling, traces of ring bulge in left tube, Henry patent action, carved fluted serpentine fences with feathered and cross-hatch engraving and marked 'HENRYS PATENT', 'No. 222', automatic safety with blue enamelled 'SAFE' detail, curved back-action locks with cocking-indicators and gold-inlaid 'COCKED' detail, fine acanthus scroll engraving with cross hatch and feathered borders, retaining some original colour-hardening and finish, 13 7/8in. highly-figured tiger stripe pistolgrip stock with two piece pistolgrip, engraved steel pistolgrip-cap (with trap), cheekpiece, sling swivels, replacement silver shield shaped escutcheon engraved with the Dholpur crest including 3/4in. rubber recoil pad (distressed), fore-end with grip-catch release lever
