Looks like a spring of some kind. I don't know why one would be there, at that angle, unless the other end had rotted off, and was hanging down. I see similar things on cars, they hold the parking brake cable away from the tire so it won't rub. Maybe it was something similar for the wires to the brakes? Ask Andy from Inland, he knows everything about these (or at least I haven't stumped him yet!)
Meddle not in the affairs of dragons, for you are crunchy, and taste good with ketchup.