The ear-shaped projection of masonry provided defense for guns and soldiers at the flank of a bastion.
An orillon (link below), sometimes referred to as an orillion, is an architectural element of a fortification.
[1][2][3][4] An orillon was generally built at the flank of a bastion, close to the adjacent defensive wall.
Additional protection was sometimes provided by lowering the gun platform in the bastion (link below).
An example is the Prince Edward's Gate (pictured in map at right) in the Charles V Wall in the British Overseas Territory of Gibraltar.