EL6171 - This is probably an 1861 pattern Hospital Corp short sword, or hanger, with the side bar of the brass guard removed in the period. I state the ambiguous origin of this sword, because this type of sidearm is not well understood currently. Robson in Swords of the British Army describes and shows the Hospital Corps sword, but with a fullered blade - however these unfullered bladed examples turn up occasionally and while it is assumed they are for the Hospital Corps, that is not certain. They may have been for some other branch of the service. Regardless of this, their design with cutlass-like blade and cast iron or gunmetal grips and brass knucklebows have their origin in Georgian naval and artillery sidearms.
This sword has the Board of Ordnance or War Department Broad Arrow mark stamped on the ricasso, so it was definitely in British Army service. The blade has grey patina, but is in good condition and seems to have been service sharpened originally (though not remaining sharp now). The blade is firm in the all-metal hilt. The brass guard clearly originally had the side branch characteristic of the Hospital Corps swords, but this has been professionally removed, so that it is barely possible to tell that it was originally there. My assumption is that this was done in period, probably because the branch got broken in use or storage. A good looking, hefty in the hand and solid hanger/cutlass, quite a rare piece with research potential.