gull call.                            
  
                                          
 the  seagull is a  metaphysics trick;  a 
 world-builder's  shortcut,  to  define a 
 section  of  reality and imply its size: 
 place  a flock of birds at  the edge and 
 make  their  calls  tesselate  over  the 
 entire volume                            
                                          
 a seagull  can be  defined by  as little 
 as  five  vertices;  six  triangles.  (i 
 would recommend handling  in  swarms  of 
 at least a dozen birds.)