Very unusual Arnold and Sons veterinary fleam. This item is very similar in design to the Charriere piece on the site used for humans. New information from a Sharp and Smith catalog indicates that it is likely this item is actually an embryotomy knife.
When disassembled you can identify the tell-tale signs of a mass-produced piece, the number marks that link portions of the item as they move through production.
Arnold & Sons mark. This mark indicates that the piece was manufactured after 1866.