So here hath been dawning
Another blue Day:
Think wilt thou let it
Slip useless away.

Thomas Carlyle (1795-1881) Scottish essayist and historian

Poem (1837-08), “Today,” st. 1
    (Source)

This poem is usually called "Today" or "To-day," though in its first appearance I can find (The Monthly Repository, Vol. 11 (1837-08)) it is titled "Lilliputian."

The poem was resurfaced in Carlyle's Critical and Miscellaneous Essays (1838-1839) in Vol. 1, Appendix 1 "Fractions (1823-1833)," item No. 7. This (with a date of 1840) is usually given as the citation.