Leonardo's 'Monna Lisa'

MAKE thyself known, Sibyl, or let despair
Of knowing thee be absolute; I wait
Hour-long and waste a soul. What word of fate
Hides 'twixt the lips which smile and still forbear?
Secret perfection! Mystery too fair!
Tangle the sense no more lest I should hate
Thy delicate tyranny, the inviolate
Poise of thy folded hands, thy fallen hair.
Nay, nay,--I wrong thee with rough words; still be
Serene, victorious, inaccessible;
Still smile but speak not; lightest irony
Lurk ever 'neath thine eyelids' shadow; still
O'ertop our knowledge; Sphinx of Italy
Allure us and reject us at thy will!