Sappho and Phaon: Sonnet XVIII

Why art thou chang'd? O Phaon! tell me why ?
Love flies reproach, when passion feels decay ;
Or, I would paint the raptures of that day,
When, in sweet converse, mingling sigh with sigh,
I mark'd the graceful languor of thine eye
As on a shady bank entranced we lay :
O ! eyes ! whose beamy radiance stole away,
As stars fade trembling from the burning sky !
Why art thou chang'd, dear source of all my woes !
Though dark my bosom's tint, through ev'ry vein
A ruby tide of purest lustre flows,
Warm'd by thy love, or chill'd by thy disdain ;
And yet no bliss this sensate being knows ;
Ah ! why is rapture so allied to pain ?