A device for calculating where a cue ball must cause an object billiard
ball to strike the bumper of a billiards table in order to drive the
object ball into a selected pocket of the billiards table of the type
having two opposed end rails and two opposed side rails. The device
includes a plotting board and a guide. The plotting board comprises a
scaled playing table portion and at least one scaled mirror table portion
having pocket positions formed thereon, wherein the mirror table adjoins
at least one of the opposed end rails or opposed side rails and is a
mirror image of the playing table portion. The plotter comprises a guide
and an object ball arm, the object ball arm having a pocket guide end and
an object end. When the guide is placed over a selected pocket position on
the mirror table portion and the object ball end of the object ball arm is
aligned with the object ball on the scaled playing table and the pocket
guide end is aligned with the guide over the selected pocket position, the
object ball arm will cross the scaled playing table at a point where the
object ball must strike the bumper of the billiards table.
