By a strange quirk of serendipity, this bit of fine art had been languishing in my uploads directory waiting for me to research it for a blog post, when reader Jeremy sent along a better copy and some information:
The painting is by pre-Raphaelite artist John Everett Millais, and it shows one Margaret Wilson, a member of the Free Church who refused to recognise the established Church of Scotland, and so was condemned to death by drowning in 1695 and left chained to the rocks in the Solway Firth. According to the Walker Gallery where the painting hangs today, witnesses to her execution reported that as the tide rose she defiantly quoted and sang from scripture, and that her hair floated around her head like a halo in the clear water.
Sadly, the painting has been Bowdlerized. When conservators x-rayed it, they discovered that it was originally painted as a nude. Millais painted Margaret in around 1871 without her shirt, with clothing being added later to placate delicate Victorian sensibilities:

Elsewhere on Bondage Blog: