  In this paper we show that to each planar line arrangement defined over the
real numbers, for which no two lines are parallel, one can write down a
corresponding relation on Dehn twists that can be read off from the
combinatorics and relative locations of intersections. This leads to an
alternate proof of Wajnryb's generalized lantern relations, and of Endo, Mark
and Horn-Morris' daisy relations.
