“A line between the two points where two sets of lines would cross if the first line of the first set were drawn from a point halfway between the center of the page and the upper left corner to a point halfway between the midpoint of the bottom side and a point halfway between the center of the page and the lower left corner; the second line of the first set from a point halfway between the midpoint of the top side and the upper left corner to a point halfway between the center of the page and the lower left corner; the first line of the second set from the midpoint of the top side to a point halfway between the midpoint of the right side and a point halfway between the cen- ter of the page and the lower right corner; the second line of the second set from the upper right corner to the center of the page.”