Stays - either wrought or cast iron - were historically applied to brick and masonry walls suffering from bowing or subsidence where the movement can be arrested by putting a steel tie through the building, They take different forms, the bracket acts to spread the force of the retaining tie on the brick or masonry. The brackets can be seen on historic buildings - particularly barns with large expanses of wall. See a separate entry for a series of smaller brackets from the same source.