The points of the plane are the 6 distinguished points in the middle of the diagram plus the 25 points that look like buttons. The 6 distinguished points form an oval in the projective plane, the buttons that contain isolated points are the 10 exterior points of the oval and the remaining buttons the interior points of the model. The 31 lines are generated by the 7 curves by rotating the diagram five times (72 degrees at a time). Note that the line which looks like a star fish also contains the point in the center of the diagram. Can you figure out which of the curves correspond to the tangents, the secants and the exterior lines of the oval? |