A semicircle is then drawn behind the bowls with a radius of 9 ft.
Three points are given to the bowl that trails the jack over both lines into the semicircle and goes over them itself.
The sectarial mark of the adherents consists of two red perpendicular lines, meeting in a semicircle at the root of the nose, and having a round red spot painted between them.
In the succeeding three definitions the centre, diameter and the semicircle are defined, while the third postulate of the same book demands the possibility of describing a circle for every " centre " and " distance."
It lies in the form of a vast semicircle on the left bank of the Rhine, 44 m.