"Ye Maidens Pretty" or "The Imprisoned Lady"
Words from Songs and Ballads of the West, S. Baring-Gould & co. 1895

Ye maidens pretty
In town and city,
I pray you pity
   My mournful strain.
A maiden weeping,
Her night-watch keeping,
In grief unsleeping
   Makes her complain:
In tower I languish
In cold and sadness,
Heart full of anguish,
   Eye full of tear;
While glades are ringing
With maidens singing,
Sweet roses bringing
   To crown the year.

Thro' hills and vallies
Thro' shaded alleys,
And pleached palis-
   Ading of grove;
Among fair bowers,
Midst fragrant flowers,
Pass sunny hours,
   And sing of love.
In tower I languish etc.

My cruel father
Gave strictest order,
By watch and warder
   I barred should be.
All in my chamber,
High out of danger,
From eye of stranger
   In misery.
In tower I languish etc.

Enclosed in mortar,
By wall and water,
A luckless daughter
   All white and wan;
Till day is breaking
My bed forsaking,
I all night waking
   Sing like the swan.
In tower I languish etc.

Sung here by Ged Fox
http://youtu.be/IVi_FM6r2j8