Walls that are circular on plan. If the radius is large enough the wall can be bonded in the normal way by using vee joints. However, for a small radius Heading Bond is widely used but may entail some cutting on the inner face; to maintain correct bond on the outer and inner faces of a curved wall it is desirable to use purpose made radius bricks sometimes known as Well Bricks. The curve can be set out with a Trammel and the subsequent courses controlled by lead bricks and outer and inner templates.