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.)