Classic Poem

I heard thy foot that stept
And broad awake I leapt:
Wouldst murder me whilst I slept?
I see thee there full well:
This darkness as of hell
Bears sparkles in its well.
Lo, thou art stepping now
And balancing to and fro
As if to a fiddle and bow;
A soundless fiddle and bow
Thou steppest and steppest, I trow,
And good time keepest thou.
I see thee from hair to toe:
To a soundless fiddle and bow
Thou steppest and steppest, I trow.
And turning back thy head,
Thou pointest a knife instead
Of the edge of an eye that's afraid.
My wrists are laid in one link
Of the chain: it shall not clink
To tell in what corner I shrink.
My wrists are drawn down by the chain:
Silently, spite of the pain,
To burst it in sunder I strain.
If I can but make shift
The iron from the floor to rift
And my arms o'er my head to lift.