This text comes from The Book of Scottish Song, edited by Alexander Whitelaw, a historical songbook transcribed on Wikisource and reproduced from the pinned revision linked below.
Canst thou leave me thus, my Katy?
Canst thou leave me thus, my Katy?
Well though know'st my aching heart,
And canst thou leave me thus for pity?
Is this thy plighted fond regard,
Thus cruelly to part, my Katy?
Is this thy faithful swain's reward—
An aching, broken heart, my Katy?
Farewell! and ne'er such sorrows tear
That fickle heart of thine, my Katy?
Thou may'st find those will love thee dear—
But not a love like mine, my Katy.
Stay, my Willie—yet believe me,
Stay, my Willie—yet believe me;
'Tweel, thou know'st na every pang
Wad wring my bosom shouldat thou leave me.
Tell me that thou yet art true,
And a' my wrongs shall be forgiven;
And when this heart proves false to thee,
Yon sun shall cease his course in heaven.
But to think I was betray'd,
That falsehood e'er our loves should sunder!
To take the flow'ret to my breast,
And find the guilefu' serpent under!
Could I hope thou'dst ne'er deceive me,
Celestial pleasures, might I choose 'em,
I'd slight, nor seek in other spheres
That heaven I'd find withiu thy bosom.