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.)