###.##.###                                          ##..####..
#..##.##..                                          #.#.#...#.
##.#.##.#.                                          .#####..##
..####.###                                          ##....#.#.
..#...##..                                          ..#...####
#.##..#.#.                                     .    #.##..#...
###.#.####                                        . .##.#.##..
#..####...                                    . ^.  .#.####.#.
##.#...#.. 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.)                 #........#
###.#.#..#                                          .#.......#
...#####.#                                          .##......#
#..#....##                                          .#.#.....#
.#.##...#.                                          .####....#
####.#..##                                          ##...#...#