I always think of this at low tide

"O Mary, go and call the cattle home,
Across the sands of Dee";
The western wind was wild and dank with foam,
And all alone went she.
The western tide crept up along the sand,
The rolling mist came down and hid the land:
And never home came she.
"Oh! is it weed, or fish, or floating hair--
A tress of golden hair,
A drownèd maiden's hair
Above the nets at sea?

(Apologies to Charles Kingsley for truncated version)