It is the bittern’s solemn cry
  Far out upon the lonely moors,
Where steel-gray pools reflect the sky,
  And mists arise in dim contours.

Save this, no murmur on their verge
  Doth stir the stillness of the reeds;
Silent the water-snakes emerge
  From writhing depths of water-weeds.

Through sedge or gorse of that morass...