In "Childe Harold's Pilgrimage," Byron wrote "___, thou deep and dark blue Ocean, roll!" What are the missing words?

Which nomadic desert people of the Middle East are famed for breeding Arabian horses? Explorer Richard Byrd's polar career began with an expedition based at Etah, on which large Danish-ruled island? Which British naval hero helped win the Battle of Cape St. Vincent in 1797? Byron was Lord Byron from age 10, but which poet had to wait until his 70s, in 1884, to become a lord? Byron's 1814 ode to which fallen ruler says "Nor till thy fall could mortals guess / Ambition's less than littleness"? Which work, set around the year 1300, describes a poet's journey through Hell, Purgatory and Heaven? Around 1415, Donatello sculpted St. George, with a relief beneath it showing the saint slaying which beast? Around 1490, which artist drew a man with outstretched arms showing that the span of a man's arms equals his height?