Vertical angles

This is a picture of a treasure map, found through google images at the URL http://tex.stackexchange.com/questions/86804/pirate-treasure-map. A treasure map is a map made by pirates so that ye can always know the location of their buried treasure. However, the "X" in a treasure map also forms a pair of vertical angles, because an x is formed of two lines, and where the lines intersect, two pairs of vertical angles are formed. Treasure maps are useful tools to give children an adventure, and are often seen in TV shows, books, and comics.