What moves that lonely man is not the boom
  Of waves that break against the cliff so strong;
Nor roar of thunder, when that travelling voice
  Is caught by rocks that carry far along.

'Tis not the groan of oak tree in its prime,
  When lightning strikes its solid heart to dust;
Nor frozen pond when, melted by the sun,
  It suddenly doth break its sparkling crust.

What moves that man is when the blind bat taps
  His window when he sits alone at night;
Or when the small bird sounds like some great beast
  Among the dead, dry leaves so frail and light;

Or when the moths on his night-pillow beat
  Such heavy blows he fears they'll break his bones;
Or when a mouse inside the papered walls,
  Comes like a tiger crunching through the stones.