Known sourcecanonical
"Verse sweetens toil, however rude the sound; She feels no biting pang the while she sings; Nor, as she turns the giddy wheel around, Revolves the sad vicissitudes of things."
Richard Gifford / Contemplation.
Contemplation.
Bartlett's Familiar Quotations, 9th ed. (Little, Brown, 1905), public domain