S is for Stability

These are used to keep masonry walls from bowing, they are connected through the building with iron rods.
Mainly fuctional,but with a decorative form. They are tied to a beam-a horizontal structural element (or to a threaded steel rod that can be tightened) and usually there will be another on the opposite side of the house. They basically bind the outer brick wall and pull it in, preventing it from bowing out- the 'S' shape spreads the force over a large area.
Amazing what comes out of a simple 'S'.