Some have suggested that the English translator is by T. A. Lacey (1853-1931) and others (ref). However hymn-books which it has been published in include the Roman Catholic Manual, or Collection of Prayers, Anthems, Hymns, etc (1802) - meaning that it must be older than this, and definitely in the public domain.
Lyrics:Hear, O thou bounteous Maker hear
Our humble vows with gracious ear;
Turn not thy saving face away
Whilst on this solemn fast we pray.
Great searcher of our hearts to thee
We here deplore our misery;
Behold, we to thy mercies fly,
Do thou thy healing grace apply.
Great are our sins, O Lord, but thou
Canst pardon more than we can do;
May our defects, like shadows, raise
The beauty and the life of grace.
May fasts extinguish in our will
The fuel and desire for ill,
And thus our souls from fetters free,
May only thirst and follow thee.
Grant, most sacred Trinity,
One undivided Unity,
That abstinence may here improve
Our claim to reign with thee above.