Then stay-sails [6] sidelong to the breeze ascend; While all to court the veering winds are placed With yards alternate square, and sharply braced. The dim horizon lowering vapours shroud, And blot the sun yet struggling in the cloud; Through the wide atmosphere, condensed with haze, His glaring orb emits a sanguine blaze. The pilots now their azimuth attend, 740 On which all courses duly form'd depend: The compass placed to catch the rising ray, [7] The quadrant's shadows studious they survey; Along the arch the gradual index slides, While Phoebus down the vertic-circle glides; Now seen on ocean's utmost verge to swim, He sweeps it vibrant with his nether limb. Thus height and polar distance are obtain'd, Then latitude and declination gain'd; In chiliads next the analogy is sought, 750 And on the sinical triangle wrought: By this magnetic variance is explored, Just angles known, and polar truth restored. The natives, while the ship departs their land, Ashore with admiration gazing stand. Majestically slow, before the breeze She moved triumphant o'er the yielding seas; Her bottom through translucent waters shone, White as the clouds beneath the blaze of noon; The bending wales [8] their contrast next display'd, 760 All fore and aft in polish'd jet array'd. Britannia, riding awful on the prow, Gazed o'er the vassal waves that roll'd below: Where'er she moved the vassal waves were seen To yield obsequious, and confess their queen. The imperial trident graced her dexter hand, Of power to rule the surge, like Moses' wand; The eternal empire of the main to keep, And guide her squadrons o'er the trembling deep. Her left, propitious, bore a mystic shield, 770 Around whose margin rolls the watery field; There her bold genius in his floating car O'er the wild billow, hurls the storm of war: And, lo! the beasts [9] that oft with jealous rage In bloody combat met, from age to age, Tamed into union, yoked in friendship's chain, Draw his proud chariot round the vanquish'd main; From the proud margin to the centre grew Shelves, rocks, and whirlpools, hideous to the view. The immortal shield from Neptune she received, 780 When first her head above the waters heaved; Loose floated o'er her limbs an azure vest, A figured 'scutcheon glitter'd on her breast; There from one parent soil for ever young, The blooming rose and hardy thistle sprung: Around her head an oaken wreath was seen, Inwove with laurels of unfading green. Such was the sculptured prow; from van to rear The artillery frown'd, a black tremendous tier!