And oftentimes great groans, and grievous stounds,

When too huge toil and labor them constrains;

And oftentimes loud strokes and ringing sounds

From under that deep rock most horribly rebounds.

“The cause some say is this. A little while

Before that Merlin died, he did intend

A brazen wall in compas to compile

About Caermerdin, and did it commend

Unto these sprites to bring to perfect end;

During which work the Lady of the Lake,